Science.gov

Sample records for passive solar homes

  1. Interior design for passive solar homes

    NASA Astrophysics Data System (ADS)

    Breen, J. C.

    1981-07-01

    The increasing emphasis on refinement of passive solar systems brought recognition to interior design as an integral part of passive solar architecture. Interior design can be used as a finetuning tool minimizing many of the problems associated with passive solar energy use in residential buildings. In addition, treatment of interior space in solar model homes may be a prime factor in determining sales success. A new style of interior design is evolving in response to changes in building from incorporating passive solar design features. The psychology behind passive solar architecture is reflected in interiors, and selection of interior components increasingly depends on the functional suitably of various interior elements.

  2. Interior design for passive solar homes

    SciTech Connect

    Breen, J. C.

    1981-07-01

    The increasing emphasis on refinement of passive solar systems has brought recognition to interior design as an integral part of passive solar architecture. Interior design can be used as a finetuning tool minimizing many of the problems associated with passive solar energy use in residential buildings. In addition, treatment of interior space in solar model homes may be a prime factor in determining sales success. A new style of interior design is evolving in response to changes in building form incorporating passive solar design features. The psychology behind passive solar architecture is reflected in interiors, and selection of interior components increasingly depends on the functional suitability of various interior elements.

  3. Approach to interior design for passive direct gain solar homes

    SciTech Connect

    Kachadorian, C.C.

    1980-01-01

    In response to requests from buyers and builders of direct gain passive solar homes interior design criteria either specific to, or emphasized by, passive solar buildings are investigated. Problems of high sunlight penetration, secondary illumination, material selection, sound control and psychology are approached. Material deterioration, fading, glare, noise, and a sense of spacial confinement can be minimized, contributing to the appeal and saleability of passive solar homes.

  4. Passive-solar homes for Texas

    NASA Astrophysics Data System (ADS)

    Garrison, M. L.

    1982-06-01

    Acceptance of passive solar technologies has been slow within the conventional building trades in Texas because it is a common misconception that solar is expensive, and data on local applications is severely limited or nonexistent. It is the purpose of this solar development to move passive solar design into the mainstream of public acceptance by helping to overcome and eliminate these barriers. Specifically, the goal is to develop a set of regional climatic building standards to help guide the conventional building trade toward the utilization of soft energy systems which will reduce overall consumption at a price and convenience most Texans can afford. To meet this objective, eight sample passive design structures are presented. These designs represent state of the art regional applications of passive solar space conditioning. The methodology used in the passive solar design process included: analysis of regional climatic data; analysis of historical regional building prototypes; determination of regional climatic design priorities and assets; prototypical design models for the discretionary housing market; quantitative thermal analysis of prototypical designs; and construction drawings of building prototypes.

  5. Mennonite Nursing Home passive solar demonstration

    SciTech Connect

    Not Available

    1984-03-01

    A long-term nursing care facility and retirement center was designed for passive solar heating. The system comprises thermal mass, thermal insulation, Trombe walls, and direct gain clerestories. Included here is a topical report, analysis of building performance, owner's perspective, designer's perspective, and summary of information dissemination activities. (MHR)

  6. Convincing the home builder to build solar homes: Evaluation of passive solar workshop for builders

    NASA Astrophysics Data System (ADS)

    Klein, S.

    1981-09-01

    In 1979-80, a pilot series of workshops for home builders was offered throughout the United States. The primary objectives of the project were to educate the home builder in passive solar design techniques, to promote favorable attitudes toward solar concepts, and to encourage builders to use solar design in residential construction. Builders and designers were targeted because they are the decision makers in the progress of commercializing solar design in new construction. The need is outlined for continued and expanded programs for builders to facilitate usage of solar design in the residential sector, based on information provided in nearly 1100 pre- and post-training forms returned.

  7. Low-cost passive solar-retrofit options for mobile homes

    SciTech Connect

    Brant, S.; Holtz, M.; Tasker, M.

    1981-03-01

    Passive solar heating and cooling retrofit options can significantly reduce the energy consumption of new and existing mobile homes. The initial efforts of the Solar Energy Research Institute to explore the solar potential for the existing stock of mobile homes and those in the production stage are described.

  8. Low-cost passive-solar retrofits for new and existing mobile homes

    NASA Astrophysics Data System (ADS)

    Brant, S.; Holtz, M.

    1981-07-01

    Passive solar heating and cooling retrofit options can significantly reduce the energy consumption of new and existing mobile homes. The initial efforts of the Solar Energy Research Institute to explore the solar potential for the existing stock of mobile homes and those in the production stage are described.

  9. Passive solar design strategies: Remodeling guidelines for conserving energy at home. [Final report

    SciTech Connect

    Not Available

    1991-12-31

    The idea of passive solar is simple, but applying it effectively does require information and attention to the details of design and construction. Some passive solar techniques are modest and low-cost, and require only small changes in remodeler`s typical practice. At the other end of the spectrum, some passive solar systems can almost eliminate a house`s need for purchased heating (and in some cases, cooling) energy -- but probably at a relatively high first cost. In between are a broad range of energy-conserving passive solar techniques. Whether or not they are cost-effective, practical and attractive enough to offer a market advantage to any individual remodeler depends on very specific factors such as local costs, climate, and market characteristics. Passive solar design strategies: Remodeling Guidelines For Conserving Energy At Homes is written to help give remodelers the information they need to make these decisions. Passive Solar Design Strategies is a package in three basic parts: The Guidelines contain information about passive solar techniques and how they work, and provides specific examples of systems which will save various percentages of energy; The Worksheets offer a simple, fill-in-the-blank method to pre-evaluate the performance of a specific design; The Worked Example demonstrates how to complete the worksheets for a typical residence.

  10. Passive solar design strategies: Remodeling guidelines for conserving energy at home

    SciTech Connect

    Not Available

    1991-01-01

    The idea of passive solar is simple, but applying it effectively does require information and attention to the details of design and construction. Some passive solar techniques are modest and low-cost, and require only small changes in remodeler's typical practice. At the other end of the spectrum, some passive solar systems can almost eliminate a house's need for purchased heating (and in some cases, cooling) energy -- but probably at a relatively high first cost. In between are a broad range of energy-conserving passive solar techniques. Whether or not they are cost-effective, practical and attractive enough to offer a market advantage to any individual remodeler depends on very specific factors such as local costs, climate, and market characteristics. Passive solar design strategies: Remodeling Guidelines For Conserving Energy At Homes is written to help give remodelers the information they need to make these decisions. Passive Solar Design Strategies is a package in three basic parts: The Guidelines contain information about passive solar techniques and how they work, and provides specific examples of systems which will save various percentages of energy; The Worksheets offer a simple, fill-in-the-blank method to pre-evaluate the performance of a specific design; The Worked Example demonstrates how to complete the worksheets for a typical residence.

  11. Passive solar design strategies: Remodeling guidelines for conserving energy at home

    NASA Astrophysics Data System (ADS)

    The idea of passive solar is simple, but applying it effectively does require information and attention to the details of design and construction. Some passive solar techniques are modest and low-cost, and require only small changes in remodeler's typical practice. At the other end of the spectrum, some passive solar systems can almost eliminate a house's need for purchased heating (and in some cases, cooling) energy - but probably at a relatively high first cost. In between are a broad range of energy-conserving passive solar techniques. Whether or not they are cost-effective, practical, and attractive enough to offer a market advantage to any individual remodeler depends on very specific factors such as local costs, climate, and market characteristics. Passive Solar Design Strategies: Remodeling Guidelines For Conserving Energy At Home is written to help give remodelers the information they need to make these decisions. Passive Solar Design Strategies is a package in three basic parts: the guidelines contain information about passive solar techniques and how they work, and provides specific examples of systems which will save various percentages of energy; the worksheets offer a simple, fill-in-the-blank method to pre-evaluate the performance of a specific design; and the worked example demonstrates how to complete the worksheets for a typical residence.

  12. Off-peak power use in passive solar homes: Performance, monitoring, and analysis of periodic heating and cooling in high mass homes

    NASA Astrophysics Data System (ADS)

    Peck, J. F.

    1981-08-01

    The thermal performance of two passive solar homes and an identical standard home used as a control are described. The peak hour electrical demand rates of these homes are compared and off peak refrigeration of homes with large quantities of thermal mass is discussed. A computer model which is being developed to assess the potential of off peak refrigeration is also described.

  13. Solar home show: Homes designed for the solar homebuilders program

    NASA Astrophysics Data System (ADS)

    1982-07-01

    Ten passive solar homes are presented that resulted from a program to demonstrate that passive solar homes can be attractive, affordable, functional, and therefore, marketable. For each home is given: the designer and builder, floor plans, perspective of the outside, passive solar and conservation features, and a comparison of the estimated heating bill for the house and a conventional house the same size. A brief discussion is included on the basics of passive solar design, ventilation and cooling, and solar access.

  14. Hodges residence: performance of a direct gain passive solar home in Iowa

    SciTech Connect

    Hodges, L.

    1980-01-01

    Results are presented for the performance of the Hodges Residence, a 2200-square-foot earth-sheltered direct gain passive solar home in Ames, Iowa, during the 1979-80 heating season, its first occupied season. No night insulation was used on its 500 square feet of double-pane glass. Total auxiliary heat required was 43 GJ (41 MBTU) gross and 26 GJ (25 MBTU) net, amounting, respectively, to 60 and 36 kJ/C/sup 0/-day-m/sup 2/ (2.9 and 1.8 BTU/F/sup 0/-day-ft/sup 2/). The heating season was unusually cloudy and included the cloudiest January in the 21 years of Ames insolation measurements. Results are also presented for the performance of the hollow-core floor which serves as the main storage mass and for the comfort range in the house.

  15. Passive solar construction handbook

    SciTech Connect

    Levy, E.; Evans, D.; Gardstein, C.

    1981-08-01

    Many of the basic elements of passive solar design are reviewed. The unique design constraints presented in passive homes are introduced and many of the salient issues influencing design decisions are described briefly. Passive solar construction is described for each passive system type: direct gain, thermal storage wall, attached sunspace, thermal storage roof, and convective loop. For each system type, important design and construction issues are discussed and case studies illustrating designed and built examples of the system type are presented. Construction details are given and construction and thermal performance information is given for the materials used in collector components, storage components, and control components. Included are glazing materials, framing systems, caulking and sealants, concrete masonry, concrete, brick, shading, reflectors, and insulators. The Load Collector Ratio method for estimating passive system performance is appended, and other analysis methods are briefly summarized. (LEW)

  16. Ozark Mountain solar home

    SciTech Connect

    Miller, B.

    1998-03-01

    If seeing is believing, Kyle and Christine Sarratt are believers. The couple has been living in their passive solar custom home for almost two years, long enough to see a steady stream of eye-opening utility bills and to experience the quality and comfort of energy-efficient design. Skeptical of solar homes at first, the Sarratts found an energy-conscious designer that showed them how they could realize their home-building dreams and live in greater comfort while spending less money. As Kyle says, {open_quotes}We knew almost nothing about solar design and weren`t looking for it, but when we realized we could get everything we wanted in a home and more, we were sold.{close_quotes} Now the couple is enjoying the great feeling of solar and wood heat in the winter, natural cooling in the summer and heating/cooling bills that average less than $20/month. The Sarratts` home overlooks a large lake near the town of Rogers, tucked up in the northwest corner of Arkansas. It is one of three completed homes out of 29 planned for the South Sun Estates subdivision, where homes are required by covenant to incorporate passive solar design principles. Orlo Stitt, owner of Stitt Energy Systems and developer of the subdivision, has been designing passive solar, energy-efficient homes for twenty years. His passive solar custom home development is the first in Arkansas.

  17. Past, present and future of passive homes in solar village 3, Athens

    NASA Astrophysics Data System (ADS)

    Kalogridis, Achilles

    Solar village 3 in Pefki, Athens, was part of an ambitious program for the promotion of solar technology, applied to a large scale social housing scheme, designed in mid 80's and firstly inhabited in the early 1990's. Among the aims of the project was the demonstration of the latest of technology in active solar systems and passive techniques, incorporated in a new settlement's layout and houses' building envelop, in order to create an energy saving, comfortable environment. More than fifteen years later, the housing complex remains the largest residential development of bioclimatic "solar" architecture in Athens, with the active and passive solar systems providing space and water heating for about 1750 inhabitants. The study focuses in the passive solar systems that have been applied to a number of the buildings of the settlement. The systems provide space heating with no need of any active mechanism, however with demand of the participation of the end users for their proper operation. The essay reviews various previous studies, monitoring reports and criticisms that have appeared throughout the past years, and identifies how the houses perform today, through a recent survey, sample monitoring and thermal comfort simulation. The report records things that have changed, features which worked well or others that did not and comments on the residents' behaviour. Interesting findings come into question, regarding the passive solar systems, their integration into the building's design, their current condition and their contribution to energy savings and thermal comfort conditions. Finally, current plans concerning the future of the settlement are highlighted, and considerations about the houses sustainability are suggested.

  18. Monitored passive-solar buildings

    NASA Astrophysics Data System (ADS)

    Jones, R. W.

    1982-06-01

    Selected performance results from six monitored passive and hybrid solar heated buildings are presented. These employ: a two story trombe wall; a thermosyphoning solar air heater with rock bin storage; a greenhouse; a composite concrete and water trombe wall; two story sunspace; and, for a mobile/modular home, direct gain and roof pond.

  19. New England style passive solar

    SciTech Connect

    Kriescher, P.

    2000-06-01

    There are homeowners throughout New England who planned for and built homes that allow them to avoid the sting of winter's high heating bills. These climate-responsive homes rely on passive solar heating, cooling and lighting. An example of such a climate-responsive/passive solar house is the home that Arthur and Terry Becker build on 6 beautiful acres (2.4 hectares) of rolling farm and woodland southeast of Andover, Connecticut, in 1981. They worked very closely with their designer, Al Eggan of K.T. Lear and Associates, to ensure that they would never have to pay for home heating oil, and that they would enjoy a level of year-round comfort that they had not experienced in conventionally built homes.

  20. Passive solar heating

    NASA Astrophysics Data System (ADS)

    Claridge, David E.; Mowris, Robert J.

    1985-11-01

    Buildings have been designed to use solar gains for winter heating for several millenia, but the quantitative basis for passive solar design has only been developed in the last decade. A simplified lumped capacitance model is used to provide insight into the physics of passive building behavior. Three passive design methods are described: the Solar Load Ratio (SLR) method based on correlations to simulation results; the Gordon/Zarmi closed form analytical mode;; and the ``unutilizability'' model of Monsen and Klein. Model predictions are compared with measured results; agreement is good if measured building characteristics are used. Numerous passive houses use less than 2 Btu/ft2-DD for auxiliary heating and consensus is developing that modest levels of passive glazing combined with superinsulation techniques can provide the best feature of both approaches.

  1. Passive-solar construction handbook

    SciTech Connect

    Levy, E.; Evans, D.; Gardstein, C.

    1981-02-01

    Many of the basic elements of passive solar design are reviewed. Passive solar construction is covered according to system type, each system type discussion including a general discussion of the important design and construction issues which apply to the particular system and case studies illustrating designed and built examples of the system type. The three basic types of passive solar systems discussed are direct gain, thermal storage wall, and attached sunspace. Thermal performance and construction information is presented for typical materials used in passive solar collector components, storage components, and control components. Appended are an overview of analysis methods and a technique for estimating performance. (LEW)

  2. Passive solar design guidelines and evaluation criteria for builders

    NASA Astrophysics Data System (ADS)

    Conkling, M. L.

    1983-11-01

    The showcase of Solar Homes, which features two model solar villages in Eldorado at Santa Fe and Rio Rancho, New Mexico is described. Key features of the project which include its privete sector character, marketplace considerations, and the need for uniform solar home quality are pointed out. Guidelines using a balance of conservation and passive solar were set and the issue of occupant comfort were addressed. The guidelines were used to establish criteria and worksheets for builders seeking entry into the Showcase project. Designs become examples of the transfer of research to practice. The guidelines for solar builders directly transfers passive solar research and technology to the builders.

  3. Passive solar energy in Washington: Results of the Washington passive solar design/build/competition

    NASA Astrophysics Data System (ADS)

    1982-03-01

    The Washington Passive Solar Design and Build Competition was held in an effort to encourage the design, construction, and marketing of moderately priced passive solar homes in Washington state. Four categories were established, including single and multi-family, new design and remodel. A number of commonly made thermal mistakes are discussed. Eight winning entries are presented along with four notable entries, for each of which is given as an overview of the design, energy conservation measures, passive heating and cooling features, system operation, and thermal performance.

  4. Passive Solar Design: Technology Fact Sheet; Office of Building Technology, State and Community Programs (BTS)

    SciTech Connect

    Southern Energy Institute

    2000-12-14

    Fact sheet for homeowners and contractors on using passive solar design features in homes can increase energy efficiency and comfort. Topics include design techniques, cost, and passive solar design tools.

  5. Evaluation of the passive solar for agriculture program

    SciTech Connect

    Not Available

    1981-09-01

    The purpose of this program is to stimulate the use of passive and hybrid solar energy for farm homes. Redirection of DOE emphasis limited the FY '81 program to information transfer on the topic to requesting groups and individuals.

  6. Solar Electricity for Homes

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2012-01-01

    Every day, the sun showers the Earth with millions of times more energy than its people use. The only problem is that energy is spread out over the entire Earth's surface and must be harvested. Engineers are learning to capture and use some of this energy to make electricity for homes. Solar panels make up the heart of a solar system. They can be…

  7. Solar Energy: Home Heating.

    ERIC Educational Resources Information Center

    Knapp, Henry H., III

    This module on home heating is one of six in a series intended for use as supplements to currently available materials on solar energy and energy conservation. Together with the recommended texts and references (sources are identified), these modules provide an effective introduction to energy conservation and solar energy technologies. The module…

  8. Passive-solar greenhouse

    SciTech Connect

    Not Available

    1982-01-01

    Our project objective was to design, construct, and operate a commercialized (16' x 50') passive, solar greenhouse. The structure was originally intended as a vegetable forcing facility to produce vegetable crops in the off-season. Building and size constraints and economic considerations convinced us to use the greenhouse for producing bedding plants and vegetable starts in the spring, high value vegetables (tomatoes, cucumbers) in the fall and forced bulbs in the winter. This crop sequence allows us to use the greenhouse all year without additional heat as the crops are adopted to the temperature regime of the greenhouse during each particular season. In our first season, the greenhouse performed beautifully. The lowest temperature recorded was 38/sup 0/F after 4 cold, cloudy days in February. The production of bedding plants has allowed us to diversify our products and the early transplants we produced were a great asset to our vegetable farming operation. Although construction cost (4.57 sq. ft.) is higher than that of a conventional polyethylene-covered, quonset-type greenhouse (approx. $1.92 sq. ft.), our annual operating cost is cheaper than that of a conventional greenhouse (0.49 cents sq. ft. versus 0.67 cents sq. ft.) due to a longer usable lifetime of the structure and the elimination of heating costs. Our structure has been toured by interested individuals, school and farm groups. We plan to publicize the structure and its advantages by promoting more visits to the site.

  9. National Passive Solar Conference, 4th, Kansas City, MO, October 3-5, 1979, Proceedings. Volume 4

    NASA Astrophysics Data System (ADS)

    Franta, G.

    1981-10-01

    Papers concern recent experience in the research, development and application of passive solar technology. Specific topics include the legislative barriers and incentives to passive solar systems, coupled thermal and lighting simulations for evaluating daylighting design effectiveness, passive solar applications in inner city housing, radiative cooling in a desert climate, salinity gradient solar ponds, the retrofit of a masonry home for passive space heating, the performances of active and passive solar domestic hot water systems, builder experience with passive solar home construction, the use of solar energy installations on farm buildings, and a method of determining the thermal performance of passive storage walls.

  10. Air infiltration and building tightness measurements in passive solar residences

    SciTech Connect

    Persily, A.K.; Grot, R.A.

    1984-05-01

    The airtightness of about fifty passive solar homes located throughout the United States was studied using low-cost measurement techniques. These homes are part of the DOE-sponsored Class B monitoring program conducted at the Solar Energy Research Institute (SERI) to evaluate the thermal performance of passive solar residential buildings. These tests provide the first set of building tightness measurements on a large group of passive solar buildings. The measurements include pressurization tests to measure airtightness and tracer gas measurements to determine air infiltration rates. The pressure tests show a variation in the airtightness of these homes from 3 to 30 exchanges/hr at 50 Pascal, with a median of 9.5 exchanges/hr. The air infiltration measurements cover a wider range from 0.05 to 3.0 exchanges/hr, with a median of 0.5 exchanges/hr. In comparing the tightness of these homes to other U.S. homes, one finds that these passive solar homes are not significantly tighter than homes built with less of an emphasis on energy use.

  11. Assessment of residential passive solar/gas-fired energy systems

    NASA Astrophysics Data System (ADS)

    Hartman, D. L.; Hirshberg, A. S.

    1982-12-01

    The study was made to provide a comprehensive analysis of the issues involved in integrating passive solar with gas-fired back-up energy systems including: characterize major passive solar technologies; analyze technical and economic requirements of back-up heating and cooling systems; evaluate potential improvements for gas-fired heating equipment that could enhance its fit with passive solar heating; investigate the feasibility of passive solar cooling coupled with gas dehumidification equipment; and identify R&D opportunities for GRI which offer benefits to the gas ratepayer and to the gas industry. Passive solar heating, because of its potential to significantly reduce home heating loads and of the ease with which electric backup systems can be installed could result in a decrease in gas market share, as a primary heating fuel in new housing.

  12. Performance analysis of 11 Denver Metro passive homes

    NASA Astrophysics Data System (ADS)

    Claridge, D. E.

    1981-07-01

    The auxiliary heating requirements for 11 passive solar homes were calculated using SLR or SUNCAT-2.4 with a standard set of basic assumptions. It is shown that: seven of the homes should use less than half as much heating fuel as typical houses, two should use about half, and two should use about two-thirds or more. These results are compared with performance estimates and show large discrepancies. Differences are attributed largely to specific differences in assumptions in every case but one.

  13. Consequences of passive smoking in home environment.

    PubMed

    Kałucka, Sylwia

    2007-01-01

    Passive smoking means cigarette smoke inhaling by people other than smokers. Passive smoker inhales tobacco smoke coming not only from side-stream, but also smoke exhaled by the smoker. Long-term tobacco smoke inhaling increases the risk of appearance of smoke related diseases (for example COPD, heart diseases), including the most dangerous types of cancer, which only few smokers realize. The aim of this study was to check whether tobacco smoke inhaling in home environment from childhood to adulthood has an influence on respiratory system of adults. The study included adults. In the study two types of participants division were used. Among 1481 persons two groups were separated. Group 1 contains people, who have never lived in home environment with active smokers, altogether 465 persons. Group 2 contains people who from birth have been exposed to cigarette smoke inhaling (altogether 1016 persons). With help of the author's questionnaire the information concerning demographic features and smoking habit were gathered. The patients underwent doctor's examination. They had a spirometric test and a chest radiogram. Statistically significant differences appear among persons with higher education who belong to two different groups. The number of children who have lived in smoke free rooms during childhood and adolescence and finished studies is bigger than the number of active smokers' children (p<0.001). Over 90% of never smokers have inhaled cigarette smoke since childhood in home environment. Chronic obstructive pulmonary disease has been diagnosed at 47.5% of active smokers, 48.3% of ex-smokers and up to 44.7% of passive smokers. Cigarette smoking and smoke inhaling for more than twenty years has a significant influence on the appearance of COPD. No statistically significant differences were noted among the three groups of participants. (p>0.05). Cigarette smoke inhaling at childhood and adolescence should be taken seriously because it causes development of chronic

  14. Solar Energy: Uses for Your Home. The CIRcular: Consumer Information Report 15.

    ERIC Educational Resources Information Center

    Bank of America NT & SA, San Francisco, CA.

    This report defines active and passive solar energy systems, describes home uses for solar energy, and offers guidelines for choosing and installing a system. Much of the information is specific to the state of California. Uses for solar energy which are presented include passive space heating, passive cooling, active space heating, household…

  15. Passive solar in China: traditional and new

    SciTech Connect

    Balcomb, J D; Balcomb, S A

    1986-04-01

    The authors' observations of a tradition of passive solar architecture in northern China are described. Tendencies for modern buildings to depart from this tradition are noted. Major passive solar research programs are discussed and experimental buildings are illustrated. It is concluded that the Chinese could realize a major advantage by combining their strong tradition of passive solar architecture with modern insulation methods and improved glazing systems.

  16. Vocational-Technical Instructors Passive-Solar Training Workshop

    NASA Astrophysics Data System (ADS)

    1981-07-01

    The successful efforts to provide training to instructors who teach residential design and construction at vocational-technical (vo-tech) schools are described. The training was directed toward those techniques one must consider when designing and/or constructing an energy efficient passive solar home.

  17. Cooperative passive-solar commercial retrofit

    NASA Astrophysics Data System (ADS)

    Brown, W. T.

    1982-12-01

    The primary objectives of this project were: the conversion of an existing south-facing storefront into a trombe'-wall passive solar collector, the sharing of information on simple low-cost energy alternatives with the local community, and the reduction of the store building's dependence on non-renewable fossil fuel for space heating. Six 6' wide pre-assembled collector glazing panels were mounted on a 12' high by 36' long portion of the south-facing masonry wall. Vent-holes were cut through the wall at each panel to provide air inlets and outlets for the collector and monitoring equipment was installed to record performance. A series of hands-on construction workshops were attended by Co-op and community members. During these sessions, collector components were assembled. The panels were installed on April 22, 1981 in celebration of Earth Day. Additional sessions were held to complete the project, make necessary modifications and install sensors. Project personnel participated in several energy-education activities, including workshops, seminars and alternative energy home tours. A community-based energy resource council was founded with the assistance of several key Co-op project members and a fully-illustrated How-To manual, entitled Passive Solar Collector: A Trombe'-Wall Retrofit Guide was published. Finally, a variety of energy conservation measures were undertaken. These included a new airlock store entry, insulated store ceiling, destratification ceiling fans and wood-burning furnaces have combined with the passive solar collector to substantially reduce the use of fuel oil for heat.

  18. Gap between active and passive solar heating

    SciTech Connect

    Balcomb, J.D.

    1985-01-01

    The gap between active and passive solar could hardly be wider. The reasons for this are discussed and advantages to narrowing the gap are analyzed. Ten years of experience in both active and passive systems are reviewed, including costs, frequent problems, performance prediction, performance modeling, monitoring, and cooling concerns. Trends are analyzed, both for solar space heating and for service water heating. A tendency for the active and passive technologies to be converging is observed. Several recommendations for narrowing the gap are presented.

  19. Performance summary of the Balcomb solar home

    NASA Astrophysics Data System (ADS)

    Balcomb, J. D.; Hedstrom, J. C.; Perry, J. E., Jr.

    1981-03-01

    The heating performance of the Balcomb passive solar home was evaluated based on detailed review of 85 channels of data. This led to a re-analysis of 176 days of data taken over the winter of 1978-79. Auxiliary heat during this winter was 7.4 million Btu which compares with 66.0 million Btu total heat losses from the house plus 46.4 million Btu losses from the greenhouse. Auxiliary heat predicted using the solar load ratio method was 8.1 million Btu. Solar savings were estimated as 57 million Btu. Good thermal comfort conditions were documented. Energy flows were tabulated for each month. Energy flows were tabulated for each month. Conclusions regarding detailed heat flow and storage in the house are presented.

  20. Energy savings obtainable through passive solar techniques

    SciTech Connect

    Balcomb, J.D.

    1980-01-01

    A passive solar energy system is one in which the thermal energy flow is by natural means, that is by radiation, conduction, or natural convection. The purpose of the paper is to provide a survey of passive solar heating experience, especially in the US. Design approaches are reviewed and examples shown. Misconceptions are discussed. Advantages are listed. The Los Alamos program of performance simulation and evaluation is described and a simplified method of performance estimation is outlined.

  1. Air quality in tightly sealed and passive homes

    SciTech Connect

    Scott, L.A.

    1981-09-01

    Indoor air quality has attracted increasing attention during the past few yars. Pollutants generated from combustion, building materials, and human activities may reach significant levels in the indoor environment to produce adverse health effects. This report deals with the classes of pollutants and their sources, and the significance of reported levels, possible health effects, and control strategies in relation to tightly sealed and passive solar construction techniques. In tightly sealed homes, residential air-to-air heat exchangers, whose design and performance are discussed, offer one method of improving air quality at reasonable cost. It is recommended that further research be implemented to identify hazardous concentrations of pollutants and set standards to minimize health impacts in the search for new energy innovations.

  2. Heterojunction solar cell with passivated emitter surface

    DOEpatents

    Olson, J.M.; Kurtz, S.R.

    1994-05-31

    A high-efficiency heterojunction solar cell is described wherein a thin emitter layer (preferably Ga[sub 0.52]In[sub 0.48]P) forms a heterojunction with a GaAs absorber layer. A passivating window layer of defined composition is disposed over the emitter layer. The conversion efficiency of the solar cell is at least 25.7%. The solar cell preferably includes a passivating layer between the substrate and the absorber layer. An anti-reflection coating is preferably disposed over the window layer. 1 fig.

  3. Heterojunction solar cell with passivated emitter surface

    DOEpatents

    Olson, Jerry M.; Kurtz, Sarah R.

    1994-01-01

    A high-efficiency heterojunction solar cell wherein a thin emitter layer (preferably Ga.sub.0.52 In.sub.0.48 P) forms a heterojunction with a GaAs absorber layer. A passivating window layer of defined composition is disposed over the emitter layer. The conversion efficiency of the solar cell is at least 25.7%. The solar cell preferably includes a passivating layer between the substrate and the absorber layer. An anti-reflection coating is preferably disposed over the window layer.

  4. Energy-conserving passive solar multi-family retrofit projects. Cycle 5, category 1: HUD Solar Heating and Cooling Demonstration Program

    NASA Astrophysics Data System (ADS)

    1981-10-01

    A total of 14 passive solar retrofit buildings are described. The concept of passive solar energy and the various types of passive systems found in the Cycle 5 projects are discussed. Each of the 14 solar designs is described, and some of the key points raised in the discussion of passive concepts are illustrated. Each project description cites the location of the passive solar home and presents the following information: grantee/builder, designer, solar designer, price, number of units, net heated area, heat load, degree days, solar fraction of the total heat load, and auxiliary heat required. Project descriptions also include data on recognition factors (the five passive elements necessary for a complete passive system), the type of auxiliary heating system used in the building, the solar water heating system (if any), and the passive cooling techniques used (if any).

  5. Residential solar home resale analysis

    SciTech Connect

    Noll, S.A.

    1980-01-01

    One of the determinants of the market acceptance of solar technologies in the residential housing sector is the value placed upon the solar property at the time of resale. The resale factor is shown to be an important economic parameter when net benefits of the solar design are considered over a typical ownership cycle rather than the life cycle of the system. Although a study of solar resale in Davis, Ca, indicates that those particular homes have been appreciating in value faster than nonsolar market comparables, no study has been made that would confirm this conclusion for markets in other geograhical locations with supporting tests of statistical significance. The data to undertake such an analysis is available through numerous local sources; however, case by case data collection is prohibitively expensive. A recommended alternative approach is to make use of real estate market data firms who compile large data bases and provide multi-variate statistical analysis packages.

  6. Passive solar manufactured buildings development and analyses

    NASA Astrophysics Data System (ADS)

    Dekieffer, R.

    1983-11-01

    Manufactured buildings which are cost effective residential and light commercial buildings are discussed. The solar energy research institute (SERI) and the Department of Energy (DOE) worked with building manufacturers design, develop, and build passive solar manufactured buildings. This development process lead to valuable information in design development and design options, cost analysis, and estimated and monitored thermal performance on all types of manufactured buildings. The scope and content are described.

  7. Tierra Nueva -- A passive solar cohousing project

    SciTech Connect

    Haggard, K.; Cooper, P.

    1999-10-01

    California architects take on the formidable challenges of designing a cohousing project, and discover that the end result is well worth the effort. The Tierra Nueva Cohousing Project consists of living units, a common house, community orchard, community gardens, community play space, space for a future shop and at the periphery of the site, parking, carports and garages. The units use thermal mass, solar heating, passive solar cooling, perimeter insulation on slabs. Design was agreed to by the community as a whole.

  8. Building America Top Innovations 2012: Community Scale High Performance with Solar - Pulte Homes

    SciTech Connect

    none,

    2013-01-01

    This Building America Top Innovations profile describes Pulte Homes of Tucson’s work with Building America to apply a suite of energy-efficiency measures integrated with passive solar design and solar water heating that reduced energy use more than 50% for a community of more than 1,000 homes.

  9. Passive solar energy information user study

    SciTech Connect

    Belew, W.W.; Wood, B.L.; Marle, T.L.; Reinhardt, C.L.

    1980-11-01

    The results of a series of telephone interviews with groups of users of information on passive solar heating and cooling are described. These results, part of a larger study on many different solar technologies, identify types of information each group needed and the best ways to get information to each group. The overall study provides baseline data about information needs in the solar community. An earlier study identified the information user groups in the solar community and the priority (to accelerate solar energy commercialization) of getting information to each group. In the current study only high-priority groups were examined. Results from seven passive groups respondents are analyzed in this report: Federally Funded Researchers, Manufacturer Representatives, Architects, Builders, Educators, Cooperative Extension Service County Agents, and Homeowners. The data will be used as input to the determination of information products and services the Solar Energy Research Institute, the Solar Energy Information Data Bank Network, and the entire information outreach community should be preparing and disseminating.

  10. Passive solar hen house--Second year

    SciTech Connect

    MacDougall, E.A.

    1980-12-01

    This paper describes the second year's study of a passive solar hen house. The first year's study demonstrated that a small flock of hens living in a solar heated environment can produce more eggs at a better feed efficiency than that predicted by the U.S. Department of Agriculture (USDA) for hens housed in standard hen housing. For this second year's work a new flock of Rhode Island Reds was raised and then divided in two groups - one housed in the solar hen house; the other in a barn. The solar housed group showed slightly better feed efficiency, but the barn housed group had better egg production. Both groups produced consistently heavier eggs than comparative commercial hens. However, the commercial hens showed higher feed efficiency than either the barn housed or the solar housed group for the 15 week test.

  11. Camp Sacajawea Passive Solar Demonstration Project

    SciTech Connect

    Not Available

    1983-08-31

    The intent of the Passive Solar Demonstration Project was to have: an actual demonstration of the effectiveness of a passive solar design and working automatic shading devices; accurate data of energy saved by the passive design and shading devices; a brochure distributed to architects, builders, and consumers, with the monitoring data and information about the project; and the continued monitoring of the building to help explain to those who are using the building the value of the system; this would not only include the 7000 members, bu visitors and other users of the facility. To accomplish these goals, a monitoring system was installed in the recently build Passive Solar Lodge at Camp Sacajawea on Casper Mountain south of Casper, Wyoming. The building was monitored continously for the remainder of the project. The installation of the automatic shading device, a curtain wall was accomplished but had some difficulty. The results indicate there is some effectiveness of the Curtain Wall, but a quantitative value would be impossible at this time.

  12. Boise Cascade: INEL solar home

    NASA Astrophysics Data System (ADS)

    Liebelt, K. H.; Novick, A. H.; Mills, J. I.

    1981-07-01

    The operating data on the Bosie Cascade-INEL solar homes located in Boise and Idaho Falls, Idaho, are summarized for the period from July 1, 1980 through March 31, 1981. All three major system functions are discussed: space heating, domestic hot water heating, and space cooling. In addition, the update data acquisition system, which allows for simultaneous acquisition and analysis of data, and also the new data reduction and analysis capabilities are discussed. The general performance of the houses during the reporting period is summarized, but it is beyond the scope of this report to present a detailed analysis of the data or to completely address existing data anomalies.

  13. Solar Energy in the Home. Revised.

    ERIC Educational Resources Information Center

    Roeder, Allen A.; Woodland, James A.

    Recommended for grades 10-12 physical, earth, or general science classes, this 5-7 day unit is designed to give students a general understanding of solar energy and its use as a viable alternative to present energy sources. Along with this technology, students examine several factors of solar energy which influence the choice of solar home site…

  14. Passive solar progress: a simplified guide to the 3rd national passive solar conference

    SciTech Connect

    Miller, H.; Howell, Y.; Richards, D.

    1980-10-01

    Some of the concepts and practices that have come to be known as passive solar heating and cooling are introduced, and a current picture of the field is presented. Much of the material presented is derived from papers given at the 3rd National Passive Solar Conference held in San Jose, California in January 1979 and sponsored by the US Department of Energy. Extracts and data from these papers have been integrated in the text with explanatory and descriptive material. In this way, it is attempted to present technical information in an introductory context. Topics include design considerations, passive and hybrid systems and applications, sizing methods and performance prediction, and implementation issues. A glossary is included. (WHK)

  15. Passive and hybrid solar manufactured housing and buildings. [Includes architectural drawings

    SciTech Connect

    Scholz, D; Bowling, C; Winter, S; Levy, E; Marks, R; Zgolinski, A

    1980-01-01

    The final design work on a passive solar two story modular home to be built by Unibilt Industries is summarized. After reviewing alternative insulation, glazing, and water wall schemes, five options were identified for detailed energy use and life cycle cost analysis. Using the PASCALC/SLR analysis procedure, the performance of the base case home and each of the energy conservation options was calculated. (MHR)

  16. The Solar Constant: A Take Home Lab

    ERIC Educational Resources Information Center

    Eaton, B. G.; And Others

    1977-01-01

    Describes a method that uses energy from the sun, absorbed by aluminum discs, to melt ice, and allows the determination of the solar constant. The take-home equipment includes Styrofoam cups, a plastic syringe, and aluminum discs. (MLH)

  17. Energy Conservation and Passive Solar Techniques in Campus Renovation.

    ERIC Educational Resources Information Center

    Probasco, Jack; And Others

    1981-01-01

    The analysis of a building from an energy conservation and passive solar potential has three aspects: building envelope, landscaping, and room utilization. Typical conservation and solar control modifications are listed. (Author/MLF)

  18. Solar Heated Homes: They're Here

    ERIC Educational Resources Information Center

    Knight, Carlton W., II; Wohlhagen, Linda

    1975-01-01

    Presents a discussion and examples of the two categories into which solar homes have been classified. Classifications are based upon the method by which the sunlight is put to use: energy conversion, utilizing photoelectric cells; and direct heating, where sunlight heats water which then heats the home. Diagrams are presented. (Author/EB)

  19. Factory-built integrated solar homes - A progress report

    SciTech Connect

    Rawlings, L.K.

    1995-12-31

    Over the past fifteen years, hundreds of people across the US have built for themselves highly advanced residences which integrated passive solar architecture; photovoltaic power systems; high-efficiency lights, appliances, and HVAC (heating, ventilating, and cooling) equipment; high-level insulation and airtight construction; and other renewable energy and energy-efficient technologies. Such a home can be referred to as an {open_quotes}integrated solar home{close_quotes}. As the essential technologies have improved in performance, price, and availability, the performance of such homes has steadily advanced to the point where they could provide amenities at more-or-less normal US standards of luxury, yet require as little as 5% to 10% of the level of fossil fuel or biomass use that are required in an average US home. However, the resources required to build such a home, both in terms of the time and dedication needed for research, design, and construction of the homes, and in terms of the additional cost of the renewable energy/energy efficient features, have prevented such construction from moving beyond a tiny handful of highly motivated homeowners and into the mainstream of residential construction. This paper has design summaries of six different houses.

  20. Passive solar space heating and cooling. (Latest citations from the NTIS Bibliographic database). NewSearch

    SciTech Connect

    Not Available

    1994-10-01

    The bibliography contains citations concerning the passive use of solar energy for space heating and cooling in buildings, houses, and homes. Citations discuss the design, performance, models, and economic analysis of heating and cooling systems. Topics include solar architecture, energy consumption analysis, energy conservation, and heat recovery. Also included are thermal comfort, quality of life, and housing for the elderly. (Contains a minimum of 209 citations and includes a subject term index and title list.)

  1. SOLCOST-PASSIVE solar energy design program: User's Guide

    SciTech Connect

    Not Available

    1980-09-01

    The SOLCOST-PASSIVE solar energy design program is a public domain interactive computer design tool intended for use by non-thermal specialists to size passive solar systems with a methodology based on the Los Alamos Solar Load Ratio method. A life cycle savings analysis is included in the program. An overview of SOLCOST-PASSIVE capabilities and the Solar Load Ratio method which it is based on is presented. A detailed guide to the SOLCOST-PASSIVE input parameters is given. Sample problems showing typical execution sessions and the resulting SOLCOST-PASSIVE output are included. Appendices A thru D provide details on the SLR method and the life cycle savings methodology of SOLCOST-PASSIVE. (MHR)

  2. Solar air-conditioning-active, hybrid and passive

    SciTech Connect

    Yellott, J. I.

    1981-04-01

    After a discussion of summer air conditioning requirements in the United States, active, hybrid, and passive cooling systems are defined. Active processes and systems include absorption, Rankine cycle, and a small variety of miscellaneous systems. The hybrid solar cooling and dehumidification technology of desiccation is covered as well as evaporative cooling. The passive solar cooling processes covered include convective, radiative and evaporative cooling. Federal and state involvement in solar cooling is then discussed. (LEW)

  3. Passive solar technology aids biogas digesters

    SciTech Connect

    Not Available

    1988-07-01

    Farming communities throughout China rely on biogas generators as a primary source of light and heat, as well as using the sludge as a nitrogen-rich fertilizer. Now researchers at Beijing's Solar Energy Laboratory have improved efficiency by building a rectangular tank out of concrete slabs, with one slanted surface painted black and covered with glass. According to a report in New Scientist, this passive solar panel generates heat in the same way as a greenhouse, raising inside temperatures by 10{degree}C and increasing biogas production by 50%. Another advantage of the new tanks is easy access, since the tank's lid sites in wells of water which form a seal against oxygen. (Old biogas tanks were made of soil, sand and a little concrete, prone to developing severe cracks which would allow oxygen to enter thus slowing down anaerobic reaction). Explains Debora MacKenzie of New Scientist: with the new tank, the farmer can simply remove the lid and attack the contents with a spade. This means that the mixture can comprise more than 10% solids. Greater density allows smaller tanks. Rural families need one cubic meter of biogas daily for light and heat; instead of the former 8 cm biogas generator, the new tanks need only be 1 cm. The prediction is that the smaller size could make biogas more popular in China's crowded towns. The biogas department is headed by He Shao Qi, who is also investigating ways to reduce production costs for the tanks.

  4. Solar technology assessment project. Volume 4: Solar air conditioning: Active, hybrid and passive

    NASA Astrophysics Data System (ADS)

    Yellott, J. I.

    1981-04-01

    The status of absorption cycle solar air conditioning and the Rankine cycle solar cooling system is reviewed. Vapor jet ejector chillers, solar pond based cooling, and photovoltaic compression air conditioning are also briefly discussed. Hybrid solar cooling by direct and indirect evaporative cooling, and dehumidification by desiccation are described and discussed. Passive solar cooling by convective and radiative processes, evaporative cooling by passive processes, and cooling with roof ponds and movable insulation are reviewed. Federal and state involvement in solar cooling is discussed.

  5. Window structure for passivating solar cells based on gallium arsenide

    NASA Technical Reports Server (NTRS)

    Barnett, Allen M. (Inventor)

    1985-01-01

    Passivated gallium arsenide solar photovoltaic cells with high resistance to moisture and oxygen are provided by means of a gallium arsenide phosphide window graded through its thickness from arsenic rich to phosphorus rich.

  6. Passive Solar Commercial Demonstration Program: Phase I. Final report

    SciTech Connect

    1981-02-10

    The passive solar retrofit of a small existing commercial/residential building is described. An add on gallery/sunspace is integrated into the existing structure both in terms of energy and architectural functioning. The sunspace solution maximizes the amount of south facing glass for solar heat gain, while still allowing a deep penetration of daylight into the existing buildings. (MHR)

  7. Solar Energy Education. Home economics: student activities. Field test edition

    SciTech Connect

    Not Available

    1981-03-01

    A view of solar energy from the standpoint of home economics is taken in this book of activities. Students are provided information on solar energy resources while performing these classroom activities. Instructions for the construction of a solar food dryer and a solar cooker are provided. Topics for study include window treatments, clothing, the history of solar energy, vitamins from the sun, and how to choose the correct solar home. (BCS)

  8. Commercial dissemination approaches for solar home systems

    SciTech Connect

    Terrado, E.

    1997-12-01

    The author discusses the issue of providing solar home systems to primarily rural areas from the perspective of how to commercialize the process. He considers two different approaches, one an open market approach and the other an exclusive market approach. He describes examples of the exclusive market approach which are in process in Argentina and Brazil. Coming from a banking background, the business aspects are discussed in detail. He points out the strengths and weaknesses of both approaches toward developing such systems.

  9. Progress in passive solar energy systems. Volume 8. Part 1

    SciTech Connect

    Hayes, J.; Andrejko, D.A.

    1983-01-01

    This book presents the papers given at a conference sponsored by the US DOE, the Solar Energy Research Institute, SolarVision, Inc., and the Southern California Solar Energy Society. The topics considered at the conference included sizing solar energy systems for agricultural applications, a farm scale ethanol production plant, the EEC wind energy RandD program, the passive solar performance assessment of an earth-sheltered house, the ARCO 1 MW photovoltaic power plant, the performance of a dendritic web photovoltaic module, second generation point focused concentrators, linear fresnel lens concentrating photovoltaic collectors, photovoltaic conversion efficiency, amorphous silicon thin film solar cells, a photovoltaic system for a shopping center, photovoltaic power generation for the utility industry, spectral solar radiation, and the analysis of insolation data.

  10. Performance predictions for passive solar water heating systems. Report 1: Performance monitoring to validate site-specific estimates of passive solar water heaters. Report 2: Laboratory report. Passive solar water heater tests

    NASA Astrophysics Data System (ADS)

    Robinson, David; Martin, Ken

    1988-05-01

    The two reports included in this publication describe work done to validate performance prediction procedures and test methods for passive solar domestic hot water systems. The reports assess established prediction procedures and investigate the validity of testing techniques. The intent is to develop methodologies for passive solar systems at a level similar to that already in place for active solar systems.

  11. Include Passive Solar in Your Renovations.

    ERIC Educational Resources Information Center

    Bender, Gerald F.; Probasco, Jack F.

    1981-01-01

    A checklist covers potential energy saving modifications in a building scheduled for renovation, and includes suggestions for room utilization, landscaping, and building envelope, solar control, and active system modifications. (Author)

  12. Passive and Hybrid Solar Energy Program

    SciTech Connect

    Not Available

    1980-11-01

    The background and scope of the program is presented in general terms. The Program Plan is summarized describing how individual projects are categorized into mission-oriented tasks according to market sector categories. The individual projects funded by DOE are presented as follows: residential buildings, commercial buildings, solar products, solar cities and towns, and agricultural buildings. A summary list of projects by institution (contractors) and indexed by market application area is included. (MHR)

  13. Passive cooling with solar updraft and evaporative downdraft chimneys

    SciTech Connect

    Mignon, G.V.; Cunningham, W.A.; Thompson, T.L.

    1985-01-01

    Computer models have been developed to describe the operation of both solar updraft and evaporative downdraft chimneys. Design studies are being conducted at the present time to use the towers for cooling an experimental, well instrumented, structure to study passive cooling in residential buildings. (MHR)

  14. Simple procedure for schematic design of passive solar buildings

    SciTech Connect

    Wray, W.O.; Kosiewicz, C.E.

    1984-01-01

    A simple procedure for use during the schematic phase of passive solar building design is presented in this article. The procedure is quantitative and accurate enough to insure that designs based on the provided starting point values of the primary building parameters will be cost effective.

  15. An economic model for passive solar designs in commercial environments

    NASA Astrophysics Data System (ADS)

    Powell, J. W.

    1980-06-01

    The model incorporates a life cycle costing approach that focuses on the costs of purchase, installation, maintenance, repairs, replacement, and energy. It includes a detailed analysis of tax laws affecting the use of solar energy in commercial buildings. Possible methods of treating difficult to measure benefits and costs, such as effects of the passive solar design on resale value of the building and on lighting costs, rental income from the building, and the use of commercial space, are presented. The model is illustrated in two case examples of prototypical solar design for low rise commercial buildings in an urban setting.

  16. RDI's Wisdom Way Solar Village Final Report: Includes Utility Bill Analysis of Occupied Homes

    SciTech Connect

    Robb Aldrich, Steven Winter Associates

    2011-07-01

    In 2010, Rural Development, Inc. (RDI) completed construction of Wisdom Way Solar Village (WWSV), a community of ten duplexes (20 homes) in Greenfield, MA. RDI was committed to very low energy use from the beginning of the design process throughout construction. Key features include: 1. Careful site plan so that all homes have solar access (for active and passive); 2. Cellulose insulation providing R-40 walls, R-50 ceiling, and R-40 floors; 3. Triple-pane windows; 4. Airtight construction (~0.1 CFM50/ft2 enclosure area); 5. Solar water heating systems with tankless, gas, auxiliary heaters; 6. PV systems (2.8 or 3.4kWSTC); 7. 2-4 bedrooms, 1,100-1,700 ft2. The design heating loads in the homes were so small that each home is heated with a single, sealed-combustion, natural gas room heater. The cost savings from the simple HVAC systems made possible the tremendous investments in the homes' envelopes. The Consortium for Advanced Residential Buildings (CARB) monitored temperatures and comfort in several homes during the winter of 2009-2010. In the Spring of 2011, CARB obtained utility bill information from 13 occupied homes. Because of efficient lights, appliances, and conscientious home occupants, the energy generated by the solar electric systems exceeded the electric energy used in most homes. Most homes, in fact, had a net credit from the electric utility over the course of a year. On the natural gas side, total gas costs averaged $377 per year (for heating, water heating, cooking, and clothes drying). Total energy costs were even less - $337 per year, including all utility fees. The highest annual energy bill for any home evaluated was $458; the lowest was $171.

  17. Passive vapor transport solar heating systems

    SciTech Connect

    Hedstrom, J.C.; Neeper, D.A.

    1985-01-01

    In the systems under consideration, refrigerant is evaporated in a solar collector and condensed in thermal storage for space or water heating located within the building at a level below that of the collector. Condensed liquid is lifted to an accumulator above the collector by the vapor pressure generated in the collector. Tests of two systems are described, and it is concluded that one of these systems offers distinct advantages.

  18. Gettering and passivation of high efficiency multicrystalline silicon solar cells

    NASA Astrophysics Data System (ADS)

    Rohatgi, A.; Narasimha, S.; Cai, L.

    1997-02-01

    A detailed study was conducted on aluminum and phosphorus gettering in HEM mc-Si and defect passivation by PECVD SiN in EFG mc-Si to achieve high efficiency solar cells on these promising photovoltaic materials. Solar cells with efficiencies as high as 18.6% (1 cm2 area) were achieved on multicrystalline silicon (mc-Si) grown by the heat exchanger method (HEM) by a process which implements impurity gettering, an effective back surface field, front surface passivation, and forming gas annealing. This represents the highest reported solar cell efficiency on mc-Si to date. PCD analysis revealed that the bulk lifetime in certain HEM samples after phosphorus gettering can be as high as 135 μs. By incorporating a deeper aluminum back surface field (Al-BSF), the back surface recombination velocity (Sb) for 0.65 Ω-cm HEM mc-Si solar cells was lowered from 10,000 cm/s to 2,000 cm/s resulting in the 18.6% efficient device. It was also observed that a screen-printed/RTP alloyed Al-BSF process could raise the efficiency of both float zone and relatively defect-free mc-Si solar cells by lowering Sb. However, this process was found to increase the electrical activity of extended defects so that mc-Si devices with a significant defect density showed an overall degradation in performance. In the case of EFG mc-Si, neural network modeling in conjunction with a study of post deposition annealing was used to provide guidelines for effective defect passivation by PECVD SiN films. Appropriate deposition and annealing conditions resulted in a 45% increase in cell efficiency due to AR coating and another 25-30% increase due to defect passivation by atomic hydrogen.

  19. Marketing and promoting solar water heaters to home builders

    SciTech Connect

    Keller, C.; Ghent, P.

    1999-12-06

    This is the final report of a four-task project to develop a marketing plan designed for businesses interested in marketing solar water heaters in the new home industry. This report outlines suggested marketing communication materials and other promotional tools focused on selling products to the new home builder. Information relevant to promoting products to the new home buyer is also included.

  20. Passive solar renovation of an existing commercial greenhouse

    SciTech Connect

    McGinnis, J.W.; Whitehead, N.

    1980-01-01

    The renovation of an existing 1800 square foot commercial greenhouse to incorporate passive solar reliant and energy conserving features is detailed. The Aquatic-Agriculture Institute for Research, a non-profit group, sponsored the project to develop efficient production methods to raise vegetables and fish at the community level. The performance of the remodeled greenhouse will be compared to the performance of the same greenhouse as it was originally designed. The restored greenhouse began operation in September 1979. Accurate fuel and temperature records maintained through-out the past winter, show the cost of back-up heating under operating conditions to be approximately $150.00. Old fuel receipts dating back into the 1940's show an average use of 2000 gallons of heating fuel each winter prior to remodeling. This would indicate a yearly fuel savings of better than 90% through the use of passive solar techniques.

  1. Environmentally friendly education: A passive solar, straw-bale school

    SciTech Connect

    Stone, L.; Dickinson, J.

    1999-07-01

    The Waldorf students in the Roaring Fork Valley of western Colorado are learning their reading, writing and arithmetic in the cozy confines of a solar heated, naturally lit, straw-bale school. The Waldorf education system, founded in 1919 by Austrian Rudolph Steiner, stresses what's appropriate for the kids, not what's easiest to teach. In constructing a new school, the Waldorf community wanted a building that would reflect their philosophy. There was a long list of requirements: natural, energy efficient, light, warm, alive, and earthy. Passive solar straw-bale construction brought together all those qualities.

  2. On the Disambiguation of Passively Measured In-home Gait Velocities from Multi-person Smart Homes

    PubMed Central

    Austin, Daniel; Hayes, Tamara L.; Kaye, Jeffrey; Mattek, Nora; Pavel, Misha

    2011-01-01

    In-home monitoring of gait velocity with passive PIR sensors in a smart home has been shown to be an effective method of continuously and unobtrusively measuring this important predictor of cognitive function and mobility. However, passive measurements of velocity are nonspecific with regard to who generated each measurement or walking event. As a result, this method is not suitable for multi-person homes without additional information to aid in the disambiguation of gait velocities. In this paper we propose a method based on Gaussian mixture models (GMMs) combined with infrequent clinical assessments of gait velocity to model in-home walking speeds of two or more residents. Modeling the gait parameters directly allows us to avoid the more difficult problem of assigning each measured velocity individually to the correct resident. We show that if the clinically measured gait velocities of residents are separated by at least 15 cm/s a GMM can be accurately fit to the in-home gait velocity data. We demonstrate the accuracy of this method by showing that the correlation between the means of the GMMs and the clinically measured gait velocities is 0.877 (p value < 0.0001) with bootstrapped 95% confidence intervals of (0.79, 0.94) for 54 measurements of 20 subjects living in multi-person homes. Example applications of using this method to track in-home mean velocities over time are also given. PMID:21572911

  3. Women: the key to a passive solar society

    SciTech Connect

    Redford, L.; Hunt, I.; O'Neill, M.L.

    1980-01-01

    Recognizing the vast untapped potential of women as a force to promote social change, Consumer Action Now (C.A.N.) has developed a National Energy Project for Women designed to encourage women to take an active role in shaping the transition to a society based on conservation, passive solar and all renewable resources. To promote a vision of a passive solar society, traditional patterns of energy use must be broken and conventional thinking changed. Key to the transition is securing the support of women. The National Energy Project for Women is uniquely designed to educate women on energy issues helping them to overcome the feeling of helplessness and to instill the vision of an alternate energy future. The formation of the Stamford Community Pilot Program is described, providing a plan for action that may be applied to other communities. It will focus on how women through their local communities can help to move this country toward reducing its dependence on foreign oil and realizing the enormous potential of passive solar.

  4. Novel Passivating/Antireflective Coatings for Space Solar Cells

    NASA Technical Reports Server (NTRS)

    Faur, Mircea; Faur, Maria; Bailey, S. G.; Flood, D. J.; Faur, H. M.; Mateescu, C. G.; Alterovitz, S. A.; Scheiman, D.; Jenkins, P. P.; Brinker, D. J.

    2005-01-01

    We are developing a novel process to grow passivating/antireflective (AR) coatings for terrestrial and space solar cells. Our approach involves a Room Temperature Wet Chemical Growth (RTWCG) process, which was pioneered, and is under development at SPECMAT, Inc., under a Reimbursable Space Act Agreement with NASA Glenn Research Center. The RTWCG passivating/AR coatings with graded index of refraction are applied in one easy step on finished (bare) cells. The RTWCG coatings grown on planar, textured and porous Si, as well as on poly-Si, CuInSe2, and III-V substrates, show excellent uniformity irrespective of surface topography, crystal orientation, size and shape. In this paper we present some preliminary results of the RTWCG coatings on Si and III-V substrates that show very good potential for use as a passivation/AR coating for space solar cell applications. Compared to coatings grown using conventional techniques, the RTWCG coatings have the potential to reduce reflection losses and improve current collection near the illuminated surface of space solar cells, while reducing the fabrication costs.

  5. Ion Implanted Passivated Contacts for Interdigitated Back Contacted Solar Cells

    SciTech Connect

    Young, David L.; Nemeth, William; LaSalvia, Vincenzo; Reedy, Robert; Bateman, Nicholas; Stradins, Pauls

    2015-06-14

    We describe work towards an interdigitated back contacted (IBC) solar cell utilizing ion implanted, passivated contacts. Formation of electron and hole passivated contacts to n-type CZ wafers using tunneling SiO2 and ion implanted amorphous silicon (a-Si) are described. P and B were ion implanted into intrinsic amorphous Si films at several doses and energies. A series of post-implant anneals showed that the passivation quality improved with increasing annealing temperatures up to 900 degrees C. The recombination parameter, Jo, as measured by a Sinton lifetime tester, was Jo ~ 14 fA/cm2 for Si:P, and Jo ~ 56 fA/cm2 for Si:B contacts. The contact resistivity for the passivated contacts, as measured by TLM patterns, was 14 milliohm-cm2 for the n-type contact and 0.6 milliohm-cm2 for the p-type contact. These Jo and pcontact values are encouraging for forming IBC cells using ion implantation to spatially define dopants.

  6. New Home Buyer Solar Water Heater Trade-Off Study

    SciTech Connect

    Symmetrics Marketing Corporation

    1999-08-18

    This report details the results of a research conducted in 1998 and 1999 and outlines a marketing deployment plan designed for businesses interested in marketing solar water heaters in the new home industry.

  7. Solar Homes: The Shape of Things to Come?

    ERIC Educational Resources Information Center

    Kovacs, Patricia A.; Rasor, William W.

    1978-01-01

    Students spent two months designing and building model solar homes. During this time, they learned about science, geology, architecture, landscaping, and interior decorating. This article describes and illustrates their work. (MA)

  8. Solar Successes: The Best of Today's Energy Efficient Homes

    SciTech Connect

    2008-01-01

    This is a brochure developed specifically for residential home builders. It provides information on basic financial factors and additional resources to consider when incorporating solar technologies into building plans.

  9. Simulation of a passive solar energy system. Master's thesis

    SciTech Connect

    Slate, M.P.

    1982-12-01

    A simple lumped capacitance-resistance model is used to simulate heat flow in a residential size structure heated passively by the sun. The model takes the form of an analogous electrical circuit. A computer program was written to analyse the circuit. By altering the input parameters of the program, the thermal performance of a wide variety of passive solar designs can be investigated for any geographical location. By comparing program generated data to data taken from experimental test cells in Los Alamos, New Mexico, it was found that the simulation program predicted energy use to within 4 percent of measured values. Also, the computer program predicted temperature swings to within 16 percent of measured swings. Correlation with empirical methods of calculating monthly and annual savings in fuel use for heating was poor. Using the simulation calculations as a base, the predictions of anual savings differed by as much as 76 percent.

  10. Optimization of storage in passive solar heating systems. Final report

    SciTech Connect

    Bahm, R.J.

    1980-05-01

    The search for a simple method of estimating the optimum amount of storage for passive solar space heating system designs and the results of that search are described. The project goals, and why the project is important are described. The major project results are presented in the order of their importance with respect to meeting the project goal. A narrative description of the project is given. Here the various approaches attempted are described, giving the reasons for failure in those areas that were not successful. The Appendices contain the bulk of data generated by this project. Most of the data is presented in graphical form. (MHR)

  11. Stable passivations for high-efficiency silicon solar cells

    NASA Astrophysics Data System (ADS)

    Gruenbaum, P. E.; Gan, J. Y.; King, R. R.; Swanson, R. M.

    Initial designs of single-crystal silicon point-contact solar cells have shown a degradation in their efficiency after being exposed to concentrated sunlight. The main mechanism appears to be an increase in recombination centers at the Si/SiO2 interface due to ultraviolet light photoinjecting electrons from the silicon conduction band into the silicon dioxide that passivates the cell's front surface. Trichloroethane, texturization, and aluminum during the forming gas anneal all contribute to the instability of the interface. A reasonably good resistance to UV light can be obtained by putting a phosphorus diffusion at the surface and can be improved further by stripping off the deposited oxide after the diffusion and regrowing a dry thermal oxide. A second technique, which utilizes ultrathin oxides and thin polysilicon films and can yield stable point-contact solar cells that are more efficient at higher concentrations, is also described.

  12. Cooperative passive-solar commercial retrofit. Final report, September 1, 1980-December 31, 1982

    SciTech Connect

    Brown, W.T.

    1982-12-01

    The primary objectives of this project were: the conversion of an existing south-facing storefront into a trombe'-wall passive solar collector, the sharing of information on simple low-cost energy alternatives with the local community, and the reduction of the store building's dependence on non-renewable fossil fuel for space heating. Six 6' wide pre-assembled collector glazing panels were mounted on a 12' high by 36' long portion of the south-facing masonry wall. Vent-holes were cut through the wall at each panel to provide air inlets and outlets for the collector and monitoring equipment was installed to record performance. A series of hands-on construction workshops were attended by Co-op and community members. During these sessions, collector components were assembled. The panels were installed on April 22, 1981 in celebration of Earth Day. Additional sessions were held to complete the project, make necessary modifications and install sensors. Project personnel participated in several energy-education activities, including workshops, seminars and alternative energy home tours. A community-based energy resource council was founded with the assistance of several key Co-op project members and a fully-illustrated How-To manual, entitled Passive Solar Collector: A Trombe'-Wall Retrofit Guide was published. Finally, a variety of energy conservation measures were undertaken. These included a new airlock store entry, insulated store ceiling, destratification ceiling fans and wood-burning furnaces have combined with the passive solar collector to substantially reduce the use of fuel oil for heat.

  13. Passive and active exercises are similarly effective in elderly nursing home residents

    PubMed Central

    Takahashi, Takeshi; Takeshima, Nobuo; Rogers, Nicole L.; Rogers, Michael E.; Islam, Mohammod Monirul

    2015-01-01

    [Purpose] The aim of this study was to compare the efficacy of passive motion exercise and active motion exercise on functional fitness in elderly nursing home residents. [Subjects and Methods] Twenty-three (female 22 and male 1) nursing home residents (84.8±4.3 yr) volunteered for this study. They were divided into a passive motion exercise group (n=12) and an active motion exercise group (n=11) and performed 30-min sessions of training twice a week for 12 weeks. Functional fitness (Arm Curl, Chair Stand, Up & Go, Sit & Reach, Back Scratch, functional Reach, and 12-min Walk tests) was evaluated before and after the intervention. [Results] No significant baseline difference was noted between the groups in measured variables. Following the 12 week intervention, no significant interaction (group × time) was noted in functional fitness variables between the groups, except for the functional reach scores (active motion exercise 40%, passive motion exercise 9%). Significant improvement over time was noted in passive motion exercise group in Arm Curl (19%), Chair Stand (15%), Up & Go (6%), and 12-min Walk (12%) scores; and in the active motion exercise group in Arm Curl (14%), Chair Stand (19%), Up & Go (11%), functional Reach (40%) and 12-min Walk (13%) scores. The adherence rates in the passive and active motion exercise groups were 95.8% and 93.1% respectively. [Conclusion] Passive motion exercise and active motion exercise were found to be similarly effective for improving the functional fitness of elderly nursing home residents. PMID:26504320

  14. Wallboard with Latent Heat Storage for Passive Solar Applications

    SciTech Connect

    Kedl, R.J.

    2001-05-31

    Conventional wallboard impregnated with octadecane paraffin [melting point-23 C (73.5 F)] is being developed as a building material with latent heat storage for passive solar and other applications. Impregnation was accomplished simply by soaking the wallboard in molten wax. Concentrations of wax in the combined product as high as 35% by weight can be achieved. Scale-up of the soaking process, from small laboratory samples to full-sized 4- by 8-ft sheets, has been successfully accomplished. The required construction properties of wallboard are maintained after impregnation, that is, it can be painted and spackled. Long-term, high-temperature exposure tests and thermal cycling tests showed no tendency of the paraffin to migrate within the wallboard, and there was no deterioration of thermal energy storage capacity. In support of this concept, a computer model was developed to handle thermal transport and storage by a phase change material (PCM) dispersed in a porous media. The computer model was confirmed by comparison with known analytical solutions and also by comparison with temperatures measured in wallboard during an experimentally generated thermal transient. Agreement between the model and known solution was excellent. Agreement between the model and thermal transient was good, only after the model was modified to allow the PCM to melt over a temperature range, rather than at a specific melting point. When the melting characteristics of the PCM (melting point, melting range, and heat of fusion), as determined from a differential scanning calorimeter plot, were used in the model, agreement between the model and transient data was very good. The confirmed computer model may now be used in conjunction with a building heating and cooling code to evaluate design parameters and operational characteristics of latent heat storage wallboard for passive solar applications.

  15. Investment in passive solar features in buildings: a survey of developers and investors

    SciTech Connect

    Not Available

    1983-01-01

    The purpose of the reported study was to explore the requirements and factors that influence nonresidential building investment decisions regarding the use of passive and hybrid solar technologies in new and retrofit building projects. The requirements and factors studied included financial resources and constraints, solar cost and performance information, available professional advice, building and land use codes and standards, and other considerations deemed important to solar investment decisions. The attitudes and experience of developers and financiers regarding investment in passive solar technology are described. Development industry decision makers and the factors and practices that influence passive solar investment decisions are identified. It is concluded that passive solar technology is not being widely adopted by the development community because it is not perceived as being competitive with other energy efficient technologies. (LEW)

  16. Building with passive solar: an application guide for the southern homeowner and builder

    SciTech Connect

    1981-03-01

    This instructional material was prepared for training workshops for builders and home designers. It includes: fundamental definitions and equations, climate and site studies, building components, passive systems and techniques, and design tools. (MHR)

  17. A passive, sun-pointing, millimeter-scale solar sail

    NASA Astrophysics Data System (ADS)

    Atchison, Justin A.; Peck, Mason A.

    2010-07-01

    Taking inspiration from the orbital dynamics of dust, we find that spacecraft length scaling is a means of enabling infinite-impulse orbits that require no feedback control. Our candidate spacecraft is a 25 μm thick, 1 cm square silicon chip equipped with signal transmitting circuitry. This design reduces the total mass to less than 7.5 mg and enables the spacecraft bus itself to serve as a solar sail with characteristic acceleration on the order of 0.1 mm/s 2. It is passive in that it maneuvers with no closed-loop actuation of orbital or attitude states. The unforced dynamics that result from an insertion orbit and a launch-vehicle separation determine its subsequent state evolution. We have developed a system architecture that uses solar radiation torques to maintain a sun-pointing heading and can be fabricated with standard microfabrication processes. This architecture has potential applications in heliocentric, geocentric, and three-body orbits.

  18. Solar passive ceiling system. Final report. [Passive solar heating system with venetian blind reflectors and latent heat storage in ceiling

    SciTech Connect

    Schneider, A.R.

    1980-01-01

    The construction of a 1200 square foot building, with full basement, built to be used as a branch library in a rural area is described. The primary heating source is a passive solar system consisting of a south facing window system. The system consists of: a set of windows located in the south facing wall only, composed of double glazed units; a set of reflectors mounted in each window which reflects sunlight up to the ceiling (the reflectors are similar to venetian blinds); a storage area in the ceiling which absorbs the heat from the reflected sunlight and stores it in foil salt pouches laid in the ceiling; and an automated curtain which automatically covers and uncovers the south facing window system. The system is totally passive and uses no blowers, pumps or other active types of heat distribution equipment. The building contains a basement which is normally not heated, and the north facing wall is bermed four feet high around the north side.

  19. Enhancing Stability of Perovskite Solar Cells to Moisture by the Facile Hydrophobic Passivation.

    PubMed

    Hwang, Insung; Jeong, Inyoung; Lee, Jinwoo; Ko, Min Jae; Yong, Kijung

    2015-08-12

    In this study, a novel and facile passivation process for a perovskite solar cell is reported. Poor stability in ambient atmosphere, which is the most critical demerit of a perovskite solar cell, is overcome by a simple passivation process using a hydrophobic polymer layer. Teflon, the hydrophobic polymer, is deposited on the top of a perovskite solar cell by a spin-coating method. With the hydrophobic passivation, the perovskite solar cell shows negligible degradation after a 30 day storage in ambient atmosphere. Suppressed degradation of the perovskite film is proved in various ways: X-ray diffraction, light absorption spectrum, and quartz crystal microbalance. This simple but effective passivation process suggests new kind of approach to enhance stability of perovskite solar cells to moisture.

  20. Development of an exterior insulating mechanism for passive solar walls. Final report

    SciTech Connect

    Christianson, L.

    1984-01-01

    A movable, mechanically operated, insulated cover for insulating and protecting the exterior side of south-facing window walls typical of passive solar homes was designed, built and tested. The shutter, which covers an 8 ft by 32 ft glass wall on a house near Brookings, South Dakota, is constructed of 4 in. of styrofoam insulation sandwiched between 3/8 in. plywood. The shutter consists of two 4-1/3 ft by 33 ft sections which are raised or lowered by cables. Each section is attached to a mechanical drive operated by a 1/2 HP electric motor coupled to a worm gear box which automatically locks in position whenever re-energized. Major problems encountered were (1) selection of a motor and gear box combination which locked in position when de-energized to avoid problems which could occur during a power outage, (2) design of the door guide system to minimize possibilities of the door sections binding or catching while moving up or down, and (3) minimizing the door system cost to enhance the economic feasibility of insulating passive window walls at night. Energy consumption can be reduced by approximately 80,000 to 90,000 Btu/ft/sup 2/-y by using this window cover device. Material costs for the cover are approximately $8.00/ft/sup 2/.

  1. Combined Active and Passive Solar Space Heating and Solar Hot Water Systems for an Elementary School in Boise, Idaho.

    ERIC Educational Resources Information Center

    Smull, Neil A.; Armstrong, Gerald L.

    1979-01-01

    Amity Elementary School in Boise, Idaho, features a solar space heating and domestic hot water system along with an earth covering to accommodate the passive aspects of energy conservation. (Author/MLF)

  2. Best practices for PV solar home system projects

    SciTech Connect

    Cosgrove-Davies, M.; Cabraal, A.

    1994-12-31

    PV solar home systems (SHS) are increasingly employed as an energy supply option for rural populations. The past 20 years` experience with small-scale SHS programs in developing countries has had mixed results. However, efforts in recent years have been more successful. In support of World Bank lending operations, the Banks Asia Alternative Energy Unit (ASTAE) has undertaken a series of case studies of currently operating SHS programs in Indonesia, Sri Lanka, the Philippines, and the Dominican Republic. These programs have varying degrees of government, NGO, and private sector involvement. This paper summarizes ASTAE`s draft Solar Photovoltaics: Best Practices for Household Electrification report which identifies the institutional, financial, and technical factors fundamental to the success of a PV solar home system project. The final version of the ASTAE report will incorporate comments from an international group of peer reviewers.

  3. Solar heating in the Los Alamos Mobile/Modular Home Unit no. 1

    NASA Astrophysics Data System (ADS)

    Hedstrom, J. C.; Moore, S. W.

    1982-04-01

    Mobile/Modular Home Unit No. 1 National Laboratory has an active system that incorporates 340 sq ft of flat black, single glazed, flat plate air heating collectors mounted at a 60 tilt on the south wall. The thermal storage is in 1536 pint jars of water. Data acquisition was accomplished with a Hewlett-Packard (HP) 3050 system controlled with a HP 9825 desk top calculator. The solar energy system has provided about 70% of the heating requirements of the house each season. Although the active solar energy system provides a major fraction of the space and domestic hot water requirements, the yearly total energy supplied is low. This is primarily because the house load is lower than expected because of passive gains and internal heat generation. Low performance is also the result of a low storage mass and several possible uncontrolled air leaks.

  4. Solar Energy and You.

    ERIC Educational Resources Information Center

    Conservation and Renewable Energy Inquiry and Referral Service (DOE), Silver Spring, MD.

    This booklet provides an introduction to solar energy by discussing: (1) how a home is heated; (2) how solar energy can help in the heating process; (3) the characteristics of passive solar houses; (4) the characteristics of active solar houses; (5) how solar heat is stored; and (6) other uses of solar energy. Also provided are 10 questions to…

  5. Passivating Window/First Layer AR Coating for Space Solar Cells

    NASA Technical Reports Server (NTRS)

    Faur, Mircea; Faur, Maria; Bailey, S. G.; Flood, D. J.; Brinker, D. J.; Alterovitz, S. A.; Wheeler, D. R.; Matesscu, G.; Goradia, C.; Goradia, M.

    2004-01-01

    Chemically grown oxides, if well designed, offer excellent surface passivation of the emitter surface of space solar cells and can be used as effective passivating window/first layer AR coating. In this paper, we demonstrate the effectiveness of using a simple room temperature wet chemical technique to grow cost effective passivating layers on solar cell front surfaces after the front grid metallization step. These passivating layers can be grown both on planar and porous surfaces. Our results show that these oxide layers: (i) can effectively passivate the from the surface, (ii) can serve as an effective optical window/first layer AR coating, (iii) are chemically, thermally and UV stable, and (iv) have the potential of improving the BOL and especially the EOL efficiency of space solar cells. The potential of using this concept to simplify the III-V based space cell heterostructures while increasing their BOL and EOL efficiency is also discussed.

  6. Wallboard with latent heat storage for passive solar applications

    SciTech Connect

    Kedl, R.J.

    1991-05-01

    Conventional wallboard impregnated with octadecane paraffin is being developed as a building material with latent heat storage for passive solar and other applications. Impregnation was accomplished simply by soaking the wallboard in molten wax. Concentrations of wax in the combined product as high as 35% by weight can be achieved. Scale-up of the soaking process, from small laboratory samples to full-sized 4- by 8-ft sheets, has been successfully accomplished. The required construction properties of wallboard are maintained after impregnation, that is, it can be painted and spackled. Long-term, high-temperature exposure tests and thermal cycling tests showed no tendency of the paraffin to migrate within the wallboard, and there was no deterioration of thermal energy storage capacity. In support of this concept, a computer model was developed to handle thermal transport and storage by a phase change material (PCM) dispersed in a porous media. The computer model was confirmed by comparison with known analytical solutions and also by comparison with temperatures measured in wallboard during an experimentally generated thermal transient. Agreement between the model and known solution was excellent. Agreement between the model and thermal transient was good, only after the model was modified to allow the PCM to melt over a temperature range, rather than at a specific melting point. When the melting characteristics of the PCM, as determined from a differential scanning calorimeter plot, were used in the model, agreement between the model and transient data was very good. 11 refs., 25 figs., 2 tabs.

  7. Light-induced anodisation of silicon for solar cell passivation

    NASA Astrophysics Data System (ADS)

    Cui, J.; Wang, X.; Opila, R.; Lennon, A.

    2013-11-01

    This paper reports a new method for forming anodic oxides on silicon surfaces using the light-induced current of pn-junction solar cells to make p-type silicon surfaces anodic. The light-induced anodisation process enables anodic oxide layers as thick as 79 nm to be formed at room temperature in a faster, more uniform, and controllable manner compared to previously reported clip-based anodisation methods. Although the effective minority carrier lifetime decreased immediately after light-induced anodisation from initial values measured with an 17 nm thermally grown oxide on both wafer surfaces, the 1-sun implied open circuit voltage of wafers on which the thermally grown oxide on the p-type surface was replaced by an anodic oxide of the same thickness could be returned to its initial value of ˜635 mV (for 3-5 Ω-cm Cz silicon wafers) after a 400 °C anneal in oxygen and then forming gas. The passivation of the formed anodic oxide layers was stable for a period of 50 days providing the oxide was protected by a 75 nm thick silicon nitride capping layer.

  8. Effect of Organic and Inorganic Passivation in Quantum-Dot-Sensitized Solar Cells.

    PubMed

    de la Fuente, Mauricio Solis; Sánchez, Rafael S; González-Pedro, Victoria; Boix, Pablo P; Mhaisalkar, S G; Rincón, Marina E; Bisquert, Juan; Mora-Seró, Iván

    2013-05-01

    The effect of semiconductor passivation on quantum-dot-sensitized solar cells (QDSCs) has been systematically characterized for CdS and CdS/ZnS. We have found that passivation strongly depends on the passivation agent, obtaining an enhancement of the solar cell efficiency for compounds containing amine and thiol groups and, in contrast, a decrease in performance for passivating agents with acid groups. Passivation can induce a change in the position of TiO2 conduction band and also in the recombination rate and nature, reflected in a change in the β parameter. Especially interesting is the finding that β, and consequently the fill factor can be increased with the passivation treatment. Applying this strategy, record cells of 4.65% efficiency for PbS-based QDSCs have been produced.

  9. Economic analysis of a passive solar multiple-family dwelling for upstate New York

    SciTech Connect

    Laquatra, J. Jr.

    1982-02-01

    The objective of this study was to examine the economic feasibility of passive solar energy as applied to a multiple-family dwelling in three upstate New York cities: Buffalo, Rochester, and Syracuse. Specifically, two passive solar applications - a Trombe wall and a direct-gain system - for a nine-unit structure designed by Total Environmental Action, Inc. were analyzed through the use of a solar economic performance code. City-specific data, including climatological information, building construction costs, utility rates, and property taxes were used, as were various economic parameters to reflect economic conditions in general and specifically those of the solar systems' owners.

  10. Home retrofitting for energy conservation and solar considerations

    NASA Astrophysics Data System (ADS)

    1981-10-01

    A manual which explains both the key concepts behind the need for and the home energy efficiency improvement is reviewed. A comprehensive picture of how home energy use is effected by the inhabitants and by the structure itself is presented. The manual explains: looking at energy, how the heat transfer occurs between houses and humans, energy audits and how to use them, energy conservation actions to do now to reduce energy use. Schemes to reduce infiltration, how to increase insulation, and what to do with windows and doors, heating and heat distribution systems, and water heaters are included. Solar energy options are explained, as well as financing and tax credits.

  11. Passive solar renovations to the Common Ground Community Restaurant. Final report

    SciTech Connect

    Not Available

    1985-01-01

    The passive solar and energy conserving renovations to the Common Ground Community Restaurant were funded primarily as a demonstration project under this program. The majority of work accomplished was (1) design and construction of a passive solar greenhouse on the existing second floor porch of the restaurant, and (2) the design and construction of energy conserving improvements to the interior of the building, consisting largely of renovating the walls and ceiling to provide an insulated space with a substantially reduced heat load.

  12. Costs of Fiber-to-the-Home Passive Optical Network Unbundling

    NASA Astrophysics Data System (ADS)

    Carmona, David; Prat, Josep; Tomkos, Ioannis; Sánchez Marco, M. Pilar

    2013-01-01

    This work considers different unbundling options for local loop unbundling in order to provide multi-operator access and consider the economical impact for the fiber-to-the-home next-generation access entrants to deploy such alternatives. It is shown that deploying wavelength division multiplexing networks is an efficient strategy to perform local loop unbundling while upgrading the gigabit passive optical network for the new era where high bandwidths are necessary for satisfying customer demand. In areas with a high population density, wavelength division multiplexing techniques are the most suitable for entrant operators to access the incumbent's network and provide service.

  13. An inexpensive economical solar heating system for homes

    NASA Technical Reports Server (NTRS)

    Allred, J. W.; Shinn, J. M., Jr.; Kirby, C. E.; Barringer, S. R.

    1976-01-01

    A low-cost solar home heating system to supplement existing warm-air heating systems is described. The report is written in three parts: (1) a brief background on solar heating, (2) experience with a demonstration system, and (3) information for the homeowner who wishes to construct such a system. Instructions are given for a solar heating installation in which the homeowner supplies all labor necessary to install off-the-shelf components estimated to cost $2,000. These components, which include solar collector, heat exchanger, water pump, storage tank, piping, and controls to make the system completely automatic, are available at local lumber yards, hardware stores, and plumbing supply stores, and are relatively simple to install. Manufacturers and prices of each component used and a rough cost analysis based on these prices are included. This report also gives performance data obtained from a demonstration system which was built and tested at the Langley Research Center.

  14. Tunnel oxide passivated contacts formed by ion implantation for applications in silicon solar cells

    NASA Astrophysics Data System (ADS)

    Reichel, Christian; Feldmann, Frank; Müller, Ralph; Reedy, Robert C.; Lee, Benjamin G.; Young, David L.; Stradins, Paul; Hermle, Martin; Glunz, Stefan W.

    2015-11-01

    Passivated contacts (poly-Si/SiOx/c-Si) doped by shallow ion implantation are an appealing technology for high efficiency silicon solar cells, especially for interdigitated back contact (IBC) solar cells where a masked ion implantation facilitates their fabrication. This paper presents a study on tunnel oxide passivated contacts formed by low-energy ion implantation into amorphous silicon (a-Si) layers and examines the influence of the ion species (P, B, or BF2), the ion implantation dose (5 × 1014 cm-2 to 1 × 1016 cm-2), and the subsequent high-temperature anneal (800 °C or 900 °C) on the passivation quality and junction characteristics using double-sided contacted silicon solar cells. Excellent passivation quality is achieved for n-type passivated contacts by P implantations into either intrinsic (undoped) or in-situ B-doped a-Si layers with implied open-circuit voltages (iVoc) of 725 and 720 mV, respectively. For p-type passivated contacts, BF2 implantations into intrinsic a-Si yield well passivated contacts and allow for iVoc of 690 mV, whereas implanted B gives poor passivation with iVoc of only 640 mV. While solar cells featuring in-situ B-doped selective hole contacts and selective electron contacts with P implanted into intrinsic a-Si layers achieved Voc of 690 mV and fill factor (FF) of 79.1%, selective hole contacts realized by BF2 implantation into intrinsic a-Si suffer from drastically reduced FF which is caused by a non-Ohmic Schottky contact. Finally, implanting P into in-situ B-doped a-Si layers for the purpose of overcompensation (counterdoping) allowed for solar cells with Voc of 680 mV and FF of 80.4%, providing a simplified and promising fabrication process for IBC solar cells featuring passivated contacts.

  15. Passive solar addition to therapeutic pre-school. Final technical report

    SciTech Connect

    Not Available

    1983-10-01

    This project consisted of designing and constructing a passive solar system on a new classroom addition to the Peanut Butter and Jelly Therapeutic Pre-School in Albuquerque, NM. The purpose of this project was to demonstrate the applicability of solar space heating systems to large institutional buildings, and to demonstrate the energy and cost savings available through the use of such systems. Preliminary estimates indicated that the passive solar systems will provide about 90 percent of the heating and cooling needs for the new classroom addition to the school.

  16. LDEF (Prelaunch), AO171 : Solar-Array-Materials Passive LDEF Experiment, Tray A08

    NASA Technical Reports Server (NTRS)

    1984-01-01

    LDEF (Prelaunch), AO171 : Solar-Array-Materials Passive LDEF Experiment, Tray A08 EL-1994-00044 LDEF (Prelaunch), AO171 : Solar-Array-Materials Passive LDEF Experiment, Tray A08 The prelaunch photograph was taken in SAEF II at KSC prior to installation of the Solar Array Materials Passive LDEF Experiment (SAMPLE) on the LDEF. Six (6) plates of passive components, provided by various experiment organizations and designated plate I thru plate VI, are shown mounted in a three (3) inch deep LDEF peripheral tray. All six plates are aluminum and attach to the LDEF experiment tray with non-magnetic stainless steel fasteners. Plate I, located in the upper right corner, consist of a combination of solar cells with and without covers, solar cell modules and solar arrays assembled on the baseplate. Plate II in the upper center section, has twenty seven (27) composite samples, carbon fiber and glass fiber, mounted on the baseplate. Plate III, in the upper left corner, consist mostly of metallized and thin polymeric films (Kapton, Mylar, TEFLON® , white Tedlar,etc.). Plate IV located in the lower right corner consist of metals and coatings mounted in an aluminum baseplate and covered with a thin aluminum coverplate that partially mask the specimen. Plate V contained thermal plastics and structural film configured into tensile and shear specimen. Plate VI was populated with solar cells and associate components (covers, encapsulants,adhesives, etc.).

  17. Starting a local conservation and passive solar retrofit program: an energy planning sourcebook

    SciTech Connect

    Barber, V; Mathews, R

    1982-02-01

    A city planner or a neighborhood activist may wish to initiate a local conservation and passive solar retrofit program but may not have previous experience in doing so. This sourcebook is designed to assist interested individuals with their energy planning efforts, from determining retrofit potential, to financing and implementing the program. An approach or methodology is provided which can be applied to determine retrofit potential in single-family residences, mobile homes, multifamily residences, and nonresidential buildings. Case studies in Albuquerque, New Mexico, are given as examples. Guidelines are provided for evaluating the economic benefits of a retrofit program through benefit-cost analysis and economic base studies at the city and neighborhood levels. Also included are approaches to community outreach, detailing how to get started, how to gain local support, and examples of successful programs throughout the US. The need for financing, the development of a local strategy, public and private financing techniques, and community energy service organizations are examined. In addition to the Albuquerque case studies, a brief technology characterization, heat-loss calculations, economic tools, and a list of resources are appended.

  18. Solar installer training: Home Builders Institute Job Corps

    SciTech Connect

    Hansen, K.; Mann, R.

    1996-10-01

    The instructors describe the solar installation training program operated since 1979 by the Home Builders Institute, the Educational Arm of the National Association of Home Builders for the US Department of Labor, Job Corps in San Diego, CA. The authors are the original instructors and have developed the program since its inception by a co-operative effort between the Solar Energy Industries Association, NAHB and US DOL. Case studies of a few of the 605 students who have gone to work over the years after the training are included. It is one of the most successful programs under the elaborate Student Performance Monitoring Information System used by all Job Corps programs. Job Corps is a federally funded residential job training program for low income persons 16--24 years of age. Discussion details the curriculum and methods used in the program including classroom, shop and community service projects. Solar technologies including all types of hot water heating, swimming pool and spa as well as photovoltaics are included.

  19. Amorphous/crystalline silicon interface passivation: Ambient-temperature dependence and implications for solar cell performance

    DOE PAGES

    Seif, Johannes P.; Krishnamani, Gopal; Demaurex, Benedicte; Ballif, Christophe; Wolf, Stefaan De

    2015-03-02

    Silicon heterojunction (SHJ) solar cells feature amorphous silicon passivation films, which enable very high voltages. We report how such passivation increases with operating temperature for amorphous silicon stacks involving doped layers and decreases for intrinsic-layer-only passivation. We discuss the implications of this phenomenon on the solar cell's temperature coefficient, which represents an important figure-of-merit for the energy yield of devices deployed in the field. We show evidence that both open-circuit voltage (Voc) and fill factor (FF) are affected by these variations in passivation and quantify these temperature-mediated effects, compared with those expected from standard diode equations. We confirm that devicesmore » with high Voc values at 25°C show better high-temperature performance. Thus, we also argue that the precise device architecture, such as the presence of charge-transport barriers, may affect the temperature-dependent device performance as well.« less

  20. Amorphous/crystalline silicon interface passivation: Ambient-temperature dependence and implications for solar cell performance

    SciTech Connect

    Seif, Johannes P.; Krishnamani, Gopal; Demaurex, Benedicte; Ballif, Christophe; Wolf, Stefaan De

    2015-03-02

    Silicon heterojunction (SHJ) solar cells feature amorphous silicon passivation films, which enable very high voltages. We report how such passivation increases with operating temperature for amorphous silicon stacks involving doped layers and decreases for intrinsic-layer-only passivation. We discuss the implications of this phenomenon on the solar cell's temperature coefficient, which represents an important figure-of-merit for the energy yield of devices deployed in the field. We show evidence that both open-circuit voltage (Voc) and fill factor (FF) are affected by these variations in passivation and quantify these temperature-mediated effects, compared with those expected from standard diode equations. We confirm that devices with high Voc values at 25°C show better high-temperature performance. Thus, we also argue that the precise device architecture, such as the presence of charge-transport barriers, may affect the temperature-dependent device performance as well.

  1. Defect passivation in multicrystalline silicon for solar cells

    NASA Astrophysics Data System (ADS)

    Tarasov, I.; Ostapenko, S.; Nakayashiki, K.; Rohatgi, A.

    2004-11-01

    We report on the effect of hydrogen passivation in ribbon multicrystalline silicon (mc-Si) wafers from SiNx:H anti-reflecting layer using simultaneous rapid thermal annealing of Al back-contact and SiNx anti-reflection coating on the front (RTP-Al /SiNx). Scanning room-temperature photoluminescence spectroscopy revealed a strong inhomogeneity in the increase of minority carrier lifetime caused by the hydrogen defect passivation in mc-Si. We present experimental evidence that RTP-Al /SiNx processing leads to strong lifetime enhancement caused by hydrogen defect passivation in low-lifetime regions of mc-Si wafers. Additional details on the hydrogenation mechanism are revealed in a course of the dehydrogenation study. Hydrogen out-diffusion shows a different rate or activation energy between high and low lifetime regions of the wafers.

  2. Application of PECVD for bulk and surface passivation of high efficiency silicon solar cells

    SciTech Connect

    Krygowski, T.; Doshi, P.; Cai, L.; Doolittle, A.; Rohatgi, A.

    1995-08-01

    Plasma enhanced chemical vapor deposition (PECVD) passivation of bulk and surface defects has been shown to be an important technique to improve the performance of multicrystalline silicon (mc-Si) and single crystalline silicon solar cells. In this paper, we report the status of our on-going investigation into the bulk and surface passivation properties of PECVD insulators for photovoltaic applications. The objective of this paper is to demonstrate the ability of PECVD films to passivate the front (emitter) surface, bulk, and back surface by proper tailoring of deposition and post-PECVD annealing conditions.

  3. Cruciate coupling and screw-home mechanism in passive knee joint during extension--flexion.

    PubMed

    Moglo, K E; Shirazi-Adl, A

    2005-05-01

    The screw-home mechanism and coupling between forces in cruciate ligaments during passive knee joint flexion were investigated for various boundary conditions, flexion axis alignments and posterior cruciate ligaments (PCL)/anterior cruciate ligament (ACL) conditions. A developed non-linear 3D finite element model was used to perform detailed elasto-static response analyses of the human tibiofemoral joint as a function of flexion angle varying from 10 degrees hyper-extension to 90 degrees flexion. The tibia rotated internally as the femur flexed and externally as the femur extended. The re-alignment of the flexion axis by +/-5 degrees rotation about the axial (distal-proximal) axis, transection of the ACL and changes in cruciate ligament initial strains substantially influenced the 'screw-home' motion. On the other hand, restraint on this coupled rotation diminished ACL forces in flexion. A remarkable coupling was predicted between ACL and PCL forces in flexion; forces in both cruciate ligaments increased as the initial strain or pretension in one of them increased whereas they both diminished as one of them was cut or became slack. This has important consequences in joint functional biomechanics following a ligament injury or replacement surgery and, hence, in the proper management of joint disorders. PMID:15797589

  4. Passive test cell data for the solar laboratory winter, 1980-81

    NASA Astrophysics Data System (ADS)

    McFarland, R. D.

    1982-05-01

    Testing was done primarily to determine the relative efficiency of various passive solar heating concepts and to obtain data that could be used to validate computer simulation programs. The passive solar systems tested were Trombe wall with and without selective absorber, water wall, phase change wall, direct gain, a heat pipe collector, and two sunspace geometries. The heating load coefficient of these cells was roughly 26 Btu/h deg F and the collector area was 23.4 sq ft, giving a load collector ratio of approximately 27 Btu/deg F day sq ft. The test cell configurations and instrumentation are detailed, and the resulting data and cell efficiencies are discussed.

  5. Passivation ability of graphene oxide demonstrated by two-different-metal solar cells.

    PubMed

    Hsu, Wen-Tzu; Tsai, Zong-Sian; Chen, Liang-Chun; Chen, Guan-Yu; Lin, Chun-Chieh; Chen, Mei-Hsin; Song, Jenn-Ming; Lin, Chu-Hsuan

    2014-12-01

    The study on graphene oxide (GO) grows rapidly in recent years. We find that graphene oxide could act as the passivation material in photovoltaic applications. Graphene oxide has been applied on Si two-different-metal solar cells. The suitable introduction of graphene oxide could result in obvious enhancement on the efficiency. The simple chemical process to deposit graphene oxide makes low thermal budget, large-area deposition, and fast production of surface passivation possible. The different procedures to incorporate graphene oxide in Si two-different-metal solar cells are compared, and 21% enhancement on the efficiency is possible with a suitable deposition method. PMID:26088990

  6. Positioning Your Library for Solar (and Financial) Gain. Improving Energy Efficiency, Lighting, and Ventilation with Primarily Passive Techniques

    ERIC Educational Resources Information Center

    Shane, Jackie

    2012-01-01

    This article stresses the importance of building design above technology as a relatively inexpensive way to reduce energy costs for a library. Emphasis is placed on passive solar design for heat and daylighting, but also examines passive ventilation and cooling, green roofs, and building materials. Passive design is weighed against technologies…

  7. Tunnel oxide passivated contacts formed by ion implantation for applications in silicon solar cells

    SciTech Connect

    Reichel, Christian; Feldmann, Frank; Müller, Ralph; Hermle, Martin; Glunz, Stefan W.; Reedy, Robert C.; Lee, Benjamin G.; Young, David L.; Stradins, Paul

    2015-11-28

    Passivated contacts (poly-Si/SiO{sub x}/c-Si) doped by shallow ion implantation are an appealing technology for high efficiency silicon solar cells, especially for interdigitated back contact (IBC) solar cells where a masked ion implantation facilitates their fabrication. This paper presents a study on tunnel oxide passivated contacts formed by low-energy ion implantation into amorphous silicon (a-Si) layers and examines the influence of the ion species (P, B, or BF{sub 2}), the ion implantation dose (5 × 10{sup 14 }cm{sup −2} to 1 × 10{sup 16 }cm{sup −2}), and the subsequent high-temperature anneal (800 °C or 900 °C) on the passivation quality and junction characteristics using double-sided contacted silicon solar cells. Excellent passivation quality is achieved for n-type passivated contacts by P implantations into either intrinsic (undoped) or in-situ B-doped a-Si layers with implied open-circuit voltages (iV{sub oc}) of 725 and 720 mV, respectively. For p-type passivated contacts, BF{sub 2} implantations into intrinsic a-Si yield well passivated contacts and allow for iV{sub oc} of 690 mV, whereas implanted B gives poor passivation with iV{sub oc} of only 640 mV. While solar cells featuring in-situ B-doped selective hole contacts and selective electron contacts with P implanted into intrinsic a-Si layers achieved V{sub oc} of 690 mV and fill factor (FF) of 79.1%, selective hole contacts realized by BF{sub 2} implantation into intrinsic a-Si suffer from drastically reduced FF which is caused by a non-Ohmic Schottky contact. Finally, implanting P into in-situ B-doped a-Si layers for the purpose of overcompensation (counterdoping) allowed for solar cells with V{sub oc} of 680 mV and FF of 80.4%, providing a simplified and promising fabrication process for IBC solar cells featuring passivated contacts.

  8. Cigarettes vs. e-cigarettes: Passive exposure at home measured by means of airborne marker and biomarkers

    SciTech Connect

    Ballbè, Montse; Martínez-Sánchez, Jose M.; Sureda, Xisca; Fu, Marcela; and others

    2014-11-15

    Background: There is scarce evidence about passive exposure to the vapour released or exhaled from electronic cigarettes (e-cigarettes) under real conditions. The aim of this study is to characterise passive exposure to nicotine from e-cigarettes' vapour and conventional cigarettes' smoke at home among non-smokers under real-use conditions. Methods: We conducted an observational study with 54 non-smoker volunteers from different homes: 25 living at home with conventional smokers, 5 living with nicotine e-cigarette users, and 24 from control homes (not using conventional cigarettes neither e-cigarettes). We measured airborne nicotine at home and biomarkers (cotinine in saliva and urine). We calculated geometric mean (GM) and geometric standard deviations (GSD). We also performed ANOVA and Student's t tests for the log-transformed data. We used Bonferroni-corrected t-tests to control the family error rate for multiple comparisons at 5%. Results: The GMs of airborne nicotine were 0.74 μg/m{sup 3} (GSD=4.05) in the smokers’ homes, 0.13 μg/m{sup 3} (GSD=2.4) in the e-cigarettes users’ homes, and 0.02 μg/m{sup 3} (GSD=3.51) in the control homes. The GMs of salivary cotinine were 0.38 ng/ml (GSD=2.34) in the smokers’ homes, 0.19 ng/ml (GSD=2.17) in the e-cigarettes users’ homes, and 0.07 ng/ml (GSD=1.79) in the control homes. Salivary cotinine concentrations of the non-smokers exposed to e-cigarette's vapour at home (all exposed ≥2 h/day) were statistically significant different that those found in non-smokers exposed to second-hand smoke ≥2 h/day and in non-smokers from control homes. Conclusions: The airborne markers were statistically higher in conventional cigarette homes than in e-cigarettes homes (5.7 times higher). However, concentrations of both biomarkers among non-smokers exposed to conventional cigarettes and e-cigarettes’ vapour were statistically similar (only 2 and 1.4 times higher, respectively). The levels of airborne nicotine and cotinine

  9. Passive and hybrid solar manufactured housing and buildings

    NASA Astrophysics Data System (ADS)

    Scholz, D.; Bowling, C.; Winter, S.; Levy, E.; Marks, R.; Zgolinski, A.

    1981-01-01

    After reviewing alternative insulation, glazing, and water wall schemes, five options were identified for detailed energy use and life cycle cost analysis. Using the PASCALC/SLR analysis procedure, the performance of the base case home and each of the energy conservation options was calculated.

  10. Low temperature front surface passivation of interdigitated back contact silicon heterojunction solar cell

    SciTech Connect

    Shu, Brent; Das, Ujjwal; Jani, Omkar; Hegedus, Steve; Birkmire, Robert

    2009-06-08

    The interdigitated back contact silicon heterojunction (IBC-SHJ) solar cell requires a low temperature front surface passivation/anti-reflection structure. Conventional silicon surface passivation using SiO2 or a-SiNx is performed at temperature higher than 400°C, which is not suitable for the IBC-SHJ cell. In this paper, we propose a PECVD a-Si:H/a-SiNx:H/a-SiC:H stack structure to passivate the front surface of crystalline silicon at low temperature. The optical properties and passivation quality of this structure are characterized and solar cells using this structure are fabricated. With 2 nm a-Si:H layer, the stack structure exhibits stable passivation with effective minority carrier lifetime higher than 2 ms, and compatible with IBC-SHJ solar cell processing. A critical advantage of this structure is that the SiC allows it to be HF resistant, thus it can be deposited as the first step in the process. This protects the a-Si/c-Si interface and maintains a low surface recombination velocity.

  11. Computational study of the Effect of Sulfur Passivation on GaAs Heterojunction Solar Cells

    NASA Astrophysics Data System (ADS)

    Yu, Ted; Laghuvamarapu, Ramesh; Yan, Liang; You, Wei; Huffaker, Diana; Ratsch, Christian

    2013-03-01

    We report DFT calculations that study the effect of sulfur passivation ((NH4)2 S and octanethiol) on GaAs surfaces. Sulfur passivation of GaAs solar cells is an area of interest, as it improves the I-V characteristics of heterojunctions by decreasing the density of surface states. We elucidate the fundamental mechanism of sulfur passivation on GaAs by showing how the sulfur species react with different reconstructed GaAs (100) and (111B) surfaces. Using state of the art hybrid functionals to calculate band structures and density of states, we find that a reconstructed GaAs surface does not have mid-gap surface states. Therefore, we show that sulfur passivation does not reduce surface states on reconstructed surfaces. We also study arsenic vacancies and adatoms on these surfaces to determine the energies of creating these imperfections. They lead to mid-gap surface states that are shown to be energetically plausible in certain GaAs surface reconstruction. We study the most energetically favorable surface reconstructions with As vacancies and show how sulfur passivation plays a role in removing surface states. These results will guide in the selection of passivating agents for GaAs solar cells and lead to a better understanding of such systems. We appreciate the support of the NSF, Grant Number: DMR-1125931

  12. CVD-Based Valence-Mending Passivation for Crystalline-Si Solar Cells

    SciTech Connect

    Tao, Meng

    2015-03-01

    The objective of this project is to investigate a new surface passivation technique, valence-mending passivation, for its applications in crystalline-Si solar cells to achieve significant efficiency improvement and cost reduction. As the enabling technique, the project includes the development of chemical vapor deposition recipes to passivate textured Si(100) and multicrystalline-Si surfaces by sulfur and the characterization of the passivated Si surfaces, including thermal stability, Schottky barrier height, contact resistance and surface recombination. One important application is to replace the Ag finger electrode in Si cells with Al to reduce cost, by ~$0.1/Wp, and allow terawatt-scale deployment of crystalline-Si solar cells. These all-Al Si cells require a low-temperature metallization process for the Al electrode, to be compatible with valence-mending passivation and to prevent Al diffusion into n-type Si. Another application is to explore valence-mending passivation of grain boundaries in multicrystalline Si by diffusing sulfur into grain boundaries, to reduce the efficiency gas between monocrystalline-Si solar cells and multicrystalline-Si cells. The major accomplishments of this project include: 1) Demonstration of chemical vapor deposition processes for valence-mending passivation of both monocrystalline Si(100) and multicrystalline Si surfaces. Record Schottky barriers have been demonstrated, with the new record-low barrier of less than 0.08 eV between Al and sulfur-passivated n-type Si(100) and the new record-high barrier of 1.14 eV between Al and sulfur-passivated p-type Si(100). On the textured p-type monocrystalline Si(100) surface, the highest barrier with Al is 0.85 eV by valence-mending passivation. 2) Demonstration of a low-temperature metallization process for Al in crystalline-Si solar cells. The new metallization process is based on electroplating of Al in a room-temperature ionic liquid. The resistivity of the electroplated Al is ~7×10–6

  13. Audio-visual summary of passive solar commercial buildings development in the MASEC region

    NASA Astrophysics Data System (ADS)

    1981-08-01

    An audio-visual presentation documenting the use of passive solar technologies in commercial buildings within the Mid-American Region is summarized. The presentation consists of 50 35-millimeter slides with accompanying narrative. The slide show gives a brief introduction to the use of direct gain, indirect gain, and isolated gain systems with commercial examples of each.

  14. Solar Energy: Energy Conservation and Passive Design Concepts: Student Material. First Edition.

    ERIC Educational Resources Information Center

    Younger, Charles; Orsak, Charles G., Jr.

    Designed for student use in "Energy Conservation and Passive Design Concepts," one of 11 courses in a 2-year associate degree program in solar technology, this manual provides readings, bibliographies, and illustrations for seven course modules. The manual, which corresponds to an instructor guide for the same course, covers the following topics:…

  15. Design and evaluation of a passive flow-through solar water pasteurization system

    SciTech Connect

    Duff, W.S.; Hodgson, D.

    1999-07-01

    Approximately three million children die each year as a result of waterborne pathogens. At any given time one billion people have a waterborne disease. Treatment of drinking water is an important step in reducing the risk of infection. The authors have designed, constructed, and begun to evaluate a passive solar water pasteurizer. This paper presents their design process and current progress of their prototype.

  16. The effect of microscopic texture on the direct plasma surface passivation of Si solar cells

    SciTech Connect

    Mehrabian, S.; Xu, S.; Qaemi, A. A.; Shokri, B.; Chan, C. S.; Ostrikov, K.

    2013-04-15

    Textured silicon surfaces are widely used in manufacturing of solar cells due to increasing the light absorption probability and also the antireflection properties. However, these Si surfaces have a high density of surface defects that need to be passivated. In this study, the effect of the microscopic surface texture on the plasma surface passivation of solar cells is investigated. The movement of 10{sup 5} H{sup +} ions in the texture-modified plasma sheath is studied by Monte Carlo numerical simulation. The hydrogen ions are driven by the combined electric field of the plasma sheath and the textured surface. The ion dynamics is simulated, and the relative ion distribution over the textured substrate is presented. This distribution can be used to interpret the quality of the Si dangling bonds saturation and consequently, the direct plasma surface passivation.

  17. 10.6% Certified Colloidal Quantum Dot Solar Cells via Solvent-Polarity-Engineered Halide Passivation.

    PubMed

    Lan, Xinzheng; Voznyy, Oleksandr; García de Arquer, F Pelayo; Liu, Mengxia; Xu, Jixian; Proppe, Andrew H; Walters, Grant; Fan, Fengjia; Tan, Hairen; Liu, Min; Yang, Zhenyu; Hoogland, Sjoerd; Sargent, Edward H

    2016-07-13

    Colloidal quantum dot (CQD) solar cells are solution-processed photovoltaics with broad spectral absorption tunability. Major advances in their efficiency have been made via improved CQD surface passivation and device architectures with enhanced charge carrier collection. Herein, we demonstrate a new strategy to improve further the passivation of CQDs starting from the solution phase. A cosolvent system is employed to tune the solvent polarity in order to achieve the solvation of methylammonium iodide (MAI) and the dispersion of hydrophobic PbS CQDs simultaneously in a homogeneous phase, otherwise not achieved in a single solvent. This process enables MAI to access the CQDs to confer improved passivation. This, in turn, allows for efficient charge extraction from a thicker photoactive layer device, leading to a certified solar cell power conversion efficiency of 10.6%, a new certified record in CQD photovoltaics.

  18. Study of novel chemical surface passivation techniques on GaAs pn junction solar cells

    SciTech Connect

    Mauk, M.G.; Xu, S.; Arent, D.J.; Mertens, R.P.; Borghs, G.

    1989-01-16

    Novel methods of GaAs surface passivation are investigated. Passivation is acheived by simple chemical treatments using aqueous solutions of Na/sub 2/S, KOH, RuCl/sub 3/, and K/sub 2/Se. GaAs pn homojunction solar cells are used to evaluate the effectiveness of these passivation techniques. A significant reduction in minority-carrier surface recombination velocity is demonstrated. In the best case, the surface recombination velocity decreased from 5 x 10/sup 6/ cm/s (untreated surface) to 10/sup 3/ cm/s. In addition, we observe improvements in solar cell photogenerated current, short wavelength spectral response, open-circuit voltage, and junction ''dark'' current.

  19. 10.6% Certified Colloidal Quantum Dot Solar Cells via Solvent-Polarity-Engineered Halide Passivation.

    PubMed

    Lan, Xinzheng; Voznyy, Oleksandr; García de Arquer, F Pelayo; Liu, Mengxia; Xu, Jixian; Proppe, Andrew H; Walters, Grant; Fan, Fengjia; Tan, Hairen; Liu, Min; Yang, Zhenyu; Hoogland, Sjoerd; Sargent, Edward H

    2016-07-13

    Colloidal quantum dot (CQD) solar cells are solution-processed photovoltaics with broad spectral absorption tunability. Major advances in their efficiency have been made via improved CQD surface passivation and device architectures with enhanced charge carrier collection. Herein, we demonstrate a new strategy to improve further the passivation of CQDs starting from the solution phase. A cosolvent system is employed to tune the solvent polarity in order to achieve the solvation of methylammonium iodide (MAI) and the dispersion of hydrophobic PbS CQDs simultaneously in a homogeneous phase, otherwise not achieved in a single solvent. This process enables MAI to access the CQDs to confer improved passivation. This, in turn, allows for efficient charge extraction from a thicker photoactive layer device, leading to a certified solar cell power conversion efficiency of 10.6%, a new certified record in CQD photovoltaics. PMID:27351104

  20. Abrams Primary School passive solar design. Phase 1. Final report

    SciTech Connect

    1980-01-01

    The general project documentation and the design process documentation for the project are presented. The following are appended: analysis of thermal transfer and internal heat contributions to the heating and cooling loads for a typical four-classroom teaching module using bin-chart temperature data, trace simulation for the original building design, Teanet simulation of original building design for the month of January 1959, Teanet simulation of Solar 2 for the month of January 1959, incremental solar cost assessment, and diffuse radiation incident on the monitor glass. (MHR)

  1. Passive thermosyphon solar heating and cooling module with supplementary heating

    NASA Technical Reports Server (NTRS)

    1977-01-01

    A collection of three quarterly reports from Sigma Research, Inc., covering progress and status from January through September 1977 are presented. Three heat exchangers are developed for use in a solar heating and cooling system for installation into single-family dwellings. Each exchanger consists of one heating and cooling module and one submerged electric water heating element.

  2. Plasma etching, texturing, and passivation of silicon solar cells

    SciTech Connect

    Ruby, D.S.; Yang, P.; Zaidi, S.; Brueck, S.; Roy, M.; Narayanan, S.

    1998-11-01

    The authors improved a self-aligned emitter etchback technique that requires only a single emitter diffusion and no alignments to form self-aligned, patterned-emitter profiles. Standard commercial screen-printed gridlines mask a plasma-etchback of the emitter. A subsequent PECVD-nitride deposition provides good surface and bulk passivation and an antireflection coating. The authors used full-size multicrystalline silicon (mc-Si) cells processed in a commercial production line and performed a statistically designed multiparameter experiment to optimize the use of a hydrogenation treatment to increase performance. They obtained an improvement of almost a full percentage point in cell efficiency when the self-aligned emitter etchback was combined with an optimized 3-step PECVD-nitride surface passivation and hydrogenation treatment. They also investigated the inclusion of a plasma-etching process that results in a low-reflectance, textured surface on multicrystalline silicon cells. Preliminary results indicate reflectance can be significantly reduced without etching away the emitter diffusion.

  3. Indonesia solar home systems project for rural electrification

    SciTech Connect

    Sanghvi, A.P.

    1997-12-01

    This paper presents, from a financing aspect the broad issues involved in a plan to provide solar home systems (SHS) to provide rural electrification in several areas of rural Indonesia. The paper discusses the approaches being used to provide funding, develop awareness of the technology, and assure the success of the project. The plan involves the use of grant money to help with some of the initial costs of such systems, and thereby to encourage local financing on a terms rather than cash basis. There are needs for market development, and development of a business structure in the country to support this type of technology. Provided this plan can succeed, it may serve as a model for further efforts.

  4. Passive test cell data for the solar laboratory, Winter 1980-81

    SciTech Connect

    McFarland, R.D.

    1982-05-01

    Testing was done during the 1980-81 winter in 400 ft/sup 3/ test cells at the Los Alamos National Laboratory Solar Lab. This testing was done primarily to determine the relative efficiency of various passive solar heating concepts and to obtain data that could be used to validate computer simulation programs. The passive solar systems tested were Trombe wall with and without selective absorber, water wall, phase-change wall, direct gain, a heat-pipe collector, and two sunspace geometries. The heating load coefficient of these cells was roughly 26 Btu/h /sup 0/F and the collector area was 23.4 ft/sup 2/, giving a load collector ratio of approximately 27 Btu//sup 0/F day ft/sup 2/. The test cell configurations and instrumentation are detailed herein, and the resulting data and cell efficiencies are discussed.

  5. Home retrofitting for energy conservation and solar considerations

    SciTech Connect

    Not Available

    1981-10-01

    This manual explains both the key concepts behind our need for and our impact on energy usage, as well as a nuts-and-bolts explanation of how to improve the energy efficiency of your home. By reviewing both the concepts and practices of energy conservation, the manual presents a comprehensive picture of how home energy use is effected by the inhabitants and by the structure itself. The manual begins with an explanation of why we are looking at energy, then proceeds to explain how the heat transfer occurs between houses and humans. Next is a chapter on energy audits and how to use them, followed by a comprehensive section on energy conservation actions to do now to reduce energy use. Conservation actions include low cost/no cost measures, schemes to reduce infiltration, how to increase insulation, and what to do with windows and doors, heating and heat distribution systems, and water heaters. Solar energy options are then briefly explained, as well as the all important issues of financing and tax credits. The manual concludes with a bibliography to direct the reader to more sources of information.

  6. Amorphous silicon carbide passivating layers for crystalline-silicon-based heterojunction solar cells

    SciTech Connect

    Boccard, Mathieu; Holman, Zachary C.

    2015-08-14

    Amorphous silicon enables the fabrication of very high-efficiency crystalline-silicon-based solar cells due to its combination of excellent passivation of the crystalline silicon surface and permeability to electrical charges. Yet, amongst other limitations, the passivation it provides degrades upon high-temperature processes, limiting possible post-deposition fabrication possibilities (e.g., forcing the use of low-temperature silver pastes). We investigate the potential use of intrinsic amorphous silicon carbide passivating layers to sidestep this issue. The passivation obtained using device-relevant stacks of intrinsic amorphous silicon carbide with various carbon contents and doped amorphous silicon are evaluated, and their stability upon annealing assessed, amorphous silicon carbide being shown to surpass amorphous silicon for temperatures above 300 °C. We demonstrate open-circuit voltage values over 700 mV for complete cells, and an improved temperature stability for the open-circuit voltage. Transport of electrons and holes across the hetero-interface is studied with complete cells having amorphous silicon carbide either on the hole-extracting side or on the electron-extracting side, and a better transport of holes than of electrons is shown. Also, due to slightly improved transparency, complete solar cells using an amorphous silicon carbide passivation layer on the hole-collecting side are demonstrated to show slightly better performances even prior to annealing than obtained with a standard amorphous silicon layer.

  7. Amorphous silicon carbide passivating layers for crystalline-silicon-based heterojunction solar cells

    SciTech Connect

    Boccard, Mathieu; Holman, Zachary C.

    2015-08-14

    With this study, amorphous silicon enables the fabrication of very high-efficiency crystalline-silicon-based solar cells due to its combination of excellent passivation of the crystalline silicon surface and permeability to electrical charges. Yet, amongst other limitations, the passivation it provides degrades upon high-temperature processes, limiting possible post-deposition fabrication possibilities (e.g., forcing the use of low-temperature silver pastes). We investigate the potential use of intrinsic amorphous silicon carbide passivating layers to sidestep this issue. The passivation obtained using device-relevant stacks of intrinsic amorphous silicon carbide with various carbon contents and doped amorphous silicon are evaluated, and their stability upon annealing assessed, amorphous silicon carbide being shown to surpass amorphous silicon for temperatures above 300°C. We demonstrate open-circuit voltage values over 700 mV for complete cells, and an improved temperature stability for the open-circuit voltage. Transport of electrons and holes across the hetero-interface is studied with complete cells having amorphous silicon carbide either on the hole-extracting side or on the electron-extracting side, and a better transport of holes than of electrons is shown. Also, due to slightly improved transparency, complete solar cells using an amorphous silicon carbide passivation layer on the hole-collecting side are demonstrated to show slightly better performances even prior to annealing than obtained with a standard amorphous silicon layer.

  8. A new structure for comparing surface passivation materials of GaAs solar cells

    NASA Technical Reports Server (NTRS)

    Desalvo, Gregory C.; Barnett, Allen M.

    1989-01-01

    The surface recombination velocity (S sub rec) for bare GaAs is typically as high as 10 to the 6th power to 10 to the 7th power cm/sec, which dramatically lowers the efficiency of GaAs solar cells. Early attempts to circumvent this problem by making an ultra thin junction (xj less than .1 micron) proved unsuccessful when compared to lowering S sub rec by surface passivation. Present day GaAs solar cells use an GaAlAs window layer to passivate the top surface. The advantages of GaAlAs in surface passivation are its high bandgap energy and lattice matching to GaAs. Although GaAlAs is successful in reducing the surface recombination velocity, it has other inherent problems of chemical instability (Al readily oxidizes) and ohmic contact formation. The search for new, more stable window layer materials requires a means to compare their surface passivation ability. Therefore, a device structure is needed to easily test the performance of different passivating candidates. Such a test device is described.

  9. Amorphous silicon carbide passivating layers for crystalline-silicon-based heterojunction solar cells

    DOE PAGES

    Boccard, Mathieu; Holman, Zachary C.

    2015-08-14

    With this study, amorphous silicon enables the fabrication of very high-efficiency crystalline-silicon-based solar cells due to its combination of excellent passivation of the crystalline silicon surface and permeability to electrical charges. Yet, amongst other limitations, the passivation it provides degrades upon high-temperature processes, limiting possible post-deposition fabrication possibilities (e.g., forcing the use of low-temperature silver pastes). We investigate the potential use of intrinsic amorphous silicon carbide passivating layers to sidestep this issue. The passivation obtained using device-relevant stacks of intrinsic amorphous silicon carbide with various carbon contents and doped amorphous silicon are evaluated, and their stability upon annealing assessed, amorphousmore » silicon carbide being shown to surpass amorphous silicon for temperatures above 300°C. We demonstrate open-circuit voltage values over 700 mV for complete cells, and an improved temperature stability for the open-circuit voltage. Transport of electrons and holes across the hetero-interface is studied with complete cells having amorphous silicon carbide either on the hole-extracting side or on the electron-extracting side, and a better transport of holes than of electrons is shown. Also, due to slightly improved transparency, complete solar cells using an amorphous silicon carbide passivation layer on the hole-collecting side are demonstrated to show slightly better performances even prior to annealing than obtained with a standard amorphous silicon layer.« less

  10. 18.5% efficient AlOx/SiNy rear passivated industrial multicrystalline silicon solar cells

    NASA Astrophysics Data System (ADS)

    Qiao, Qi; Lu, Hongyan; Ge, Jian; Xi, Xi; Chen, Rulong; Yang, Jian; Zhu, Jingbing; Shi, Zhengrong; Chu, Junhao

    2014-06-01

    Due to the trend toward thinner and higher efficient crystalline silicon solar cells, excellent rear surface passivation and internal optical reflectance have become more and more important. Aluminum oxide (AlOx) capped with silicon nitride (SiNy), which is considered as one of the most promising candidates to achieve superior rear passivation and internal reflectance, has to date been mostly used for the rear side of p-type monocrystalline silicon (mono-Si) solar cells. In this paper, we have optimized rear AlOx/SiNy stacks deposited by industrial plasma enhanced chemical vapor deposition (PECVD) for multicrystalline silicon (mc-Si) passivated emitter and rear cells (PERC). Sufficient passivation activation effect from industrial fast-firing process and SiNy deposition process have been demonstrated, so the samples were not subjected to additional thermal treatment process in the cell fabrication flow. For rear AlOx/SiNy stack, it is shown that when PECVD AlOx is thicker than 40 nm, apparent blisters in fired AlOx deteriorate the cell performance, and the appropriate SiNy capping is N-rich SiNy with thickness of at least 180 nm. After process optimization with the least additional process steps, independently confirmed efficiency of 18.5% for Pluto-PERC with PECVD AlOx/SiNy rear passivation on standard 156 mm × 156 mm p-type mc-Si wafers has been achieved.

  11. Advanced Passivation Technology and Loss Factor Minimization for High Efficiency Solar Cells.

    PubMed

    Park, Cheolmin; Balaji, Nagarajan; Jung, Sungwook; Choi, Jaewoo; Ju, Minkyu; Lee, Seunghwan; Kim, Jungmo; Bong, Sungjae; Chung, Sungyoun; Lee, Youn-Jung; Yi, Junsin

    2015-10-01

    High-efficiency Si solar cells have attracted great attention from researchers, scientists, photovoltaic (PV) industry engineers for the past few decades. With thin wafers, surface passivation becomes necessary to increase the solar cells efficiency by overcoming several induced effects due to associated crystal defects and impurities of c-Si. This paper discusses suitable passivation schemes and optimization techniques to achieve high efficiency at low cost. SiNx film was optimized with higher transmittance and reduced recombination for using as an effective antireflection and passivation layer to attain higher solar cell efficiencies. The higher band gap increased the transmittance with reduced defect states that persisted at 1.68 and 1.80 eV in SiNx films. The thermal stability of SiN (Si-rich)/SiN (N-rich) stacks was also studied. Si-rich SiN with a refractive index of 2.7 was used as a passivation layer and N-rich SiN with a refractive index of 2.1 was used for thermal stability. An implied Voc of 720 mV with a stable lifetime of 1.5 ms was obtained for the stack layer after firing. Si-N and Si-H bonding concentration was analyzed by FTIR for the correlation of thermally stable passivation mechanism. The passivation property of spin coated Al2O3 films was also investigated. An effective surface recombination velocity of 55 cm/s with a high density of negative fixed charges (Qf) on the order of 9 x 10(11) cm(-2) was detected in Al2O3 films.

  12. Report on tests of a passive phase change solar diode for space heating

    SciTech Connect

    Maloney, T.J.; Wattles, G.S.

    1982-01-01

    Passive solar space conditioning systems suffer from the need for, and high cost of movable insulation devices to limit nighttime losses. Additionally, phase change materials (PCM) which melt only partially have been found to be less than cost-effective when compared to the low cost and predictable performance of water mass. Current PCM products used in passive applications suffer from low melt percentages due to insufficient exposure to insolation. Flow visualization tests under heating and cooling cycles have shown a unique diode device to show promise for space heating, cooling and water heating applications.

  13. Localized ohmic contact through a passivation dielectric for solar cell rear surface design

    NASA Astrophysics Data System (ADS)

    Western, Ned J.; Sung, Andrew; Wenham, Stuart R.; Bremner, Stephen P.

    2013-06-01

    We report the demonstration of a method for forming localized ohmic contact through dielectric passivation layers, via a laser doped region, with no etching prior to metal deposition. A simple bench top voltage source contacted to the gate and bulk of a test Metal-Insulator-Semiconductor device facilitates localized heating leading to ohmic contact formation. The surface passivation qualities of the dielectrics are preserved away from the contact region using this method, as hard dielectric breakdown is restricted to the laser doped region. This is a potential technique for precisely contacting rear surface of high efficiency solar cells.

  14. The home-made in situ passive flux sampler for the measurement of monoterpene emission flux: preliminary studies.

    PubMed

    Marć, Mariusz; Namieśnik, Jacek; Zabiegała, Bożena

    2015-09-01

    The paper presents the construction and metrological characteristics of the home-made in situ passive flux sampler, an analytical tool representing small-scale emission chambers working in situ and passively sampling analytes from the gaseous phase. The sorption element was a cylindrical container made of stainless steel net, packed with a carbon sorbent bed-graphitized charcoal, Carbograph 4 (35/50 mesh). The recommended working/exposure time of the constructed passive device was determined by carrying out model tests in the laboratory. In addition, a preliminary study was conducted to determine the rate of the emission flux of selected monoterpenes released from the surface of wood-based indoor materials (laminated chipboard) used in residential areas.

  15. A magnesium/amorphous silicon passivating contact for n-type crystalline silicon solar cells

    NASA Astrophysics Data System (ADS)

    Wan, Yimao; Samundsett, Chris; Yan, Di; Allen, Thomas; Peng, Jun; Cui, Jie; Zhang, Xinyu; Bullock, James; Cuevas, Andres

    2016-09-01

    Among the metals, magnesium has one of the lowest work functions, with a value of 3.7 eV. This makes it very suitable to form an electron-conductive cathode contact for silicon solar cells. We present here the experimental demonstration of an amorphous silicon/magnesium/aluminium (a-Si:H/Mg/Al) passivating contact for silicon solar cells. The conduction properties of a thermally evaporated Mg/Al contact structure on n-type crystalline silicon (c-Si) are investigated, achieving a low resistivity Ohmic contact to moderately doped n-type c-Si (˜5 × 1015 cm-3) of ˜0.31 Ω cm2 and ˜0.22 Ω cm2 for samples with and without an amorphous silicon passivating interlayer, respectively. Application of the passivating cathode to the whole rear surface of n-type front junction c-Si solar cells leads to a power conversion efficiency of 19% in a proof-of-concept device. The low thermal budget of the cathode formation, its dopant-less nature, and the simplicity of the device structure enabled by the Mg/Al contact open up possibilities in designing and fabricating low-cost silicon solar cells.

  16. Silicon diffusion in aluminum for rear passivated solar cells

    SciTech Connect

    Urrejola, Elias; Peter, Kristian; Plagwitz, Heiko; Schubert, Gunnar

    2011-04-11

    We show that the lateral spread of silicon in a screen-printed aluminum layer increases by (1.50{+-}0.06) {mu}m/ deg. C, when increasing the peak firing temperature within an industrially applicable range. In this way, the maximum spread limit of diffused silicon in aluminum is predictable and does not depend on the contact area size but on the firing temperature. Therefore, the geometry of the rear side pattern can influence not only series resistance losses within the solar cell but the process of contact formation itself. In addition, too fast cooling lead to Kirkendall void formations instead of an eutectic layer.

  17. Effect of plants on sunspace passive solar heating

    SciTech Connect

    Best, E.D.; McFarland, R.D.

    1985-01-01

    The effect of plants on sunspace thermal performance is investigated, based on experiments done in Los Alamos using two test rooms with attached sunspaces, which were essentially identical except for the presence of plants in one. Performance is related to plant transpiration, evaporation from the soil, condensation on the glazing and the absorbtance of solar energy by the lightweight leaves. Performance effects have been quantified by measurements of auxiliary heat consumption in the test rooms and analyzed by means of energy balance calculations. A method for estimating the transpiration rate is presented.

  18. Passive solar retrofit for the Broadmoor sanctuary barn

    SciTech Connect

    Ives, G.; Saunders, N.B.

    1980-01-01

    A large barn is to be converted to an energy efficient Audubon headquarters by a combination of direct gain, direct to store, and thermosiphon solar systems. The resulting combination looks very promising for general purpose retrofit since the costs appear low, the performance seems good, and the design is likely to be adaptable to many structures as a simple addition to the south face. Inputs of sun, air, and water are carefully integrated with storage. Two separate collection-storage-distribution loops are incorporated; one within the other. North wall heat collection is possible. Funds for construction are now being sought.

  19. LDEF (Flight), AO171 : Solar-Array-Materials Passive LDEF Experiment, Tray A08

    NASA Technical Reports Server (NTRS)

    1990-01-01

    LDEF (Flight), AO171 : Solar-Array-Materials Passive LDEF Experiment, Tray A08 EL-1994-00666 LDEF (Flight), AO171 : Solar-Array-Materials Passive LDEF Experiment, Tray A08 The flight photograph was taken from the Orbiter aft flight deck during the LDEF retrieval prior to berthing the LDEF in the Orbiter cargo bay and shows the Solar Array Materials Passive LDEF Experiment (SAMPLE) on the LDEF. Six (6) plates of passive components, provided by various experiment organizations and designated plate I thru plate VI, are shown mounted in a three (3) inch deep LDEF peripheral tray. All six plates are aluminum and attach to the LDEF experiment tray with non-magnetic stainless steel fasteners. Plate I, located in the upper left corner, consist of a combination of solar cells with and without covers, solar cell modules and solar arrays assembled on the baseplate. Two of the four solar arrays are missing and one appears to be attached at only one corner. Other components appear to be secure. Plate II in the left center section, has twenty-seven (27) composite samples, carbon fiber and glass fiber, mounted on the baseplate. The composites appear to be intact with no physical damage. Plate III, in the lower left corner, consist mostly of metallized and thin polymeric films (Kapton, Mylar, TEFLON® , white Tedlar,etc.). The thin films without protective coatings sustained significant damage and most were destroyed. The metallized film apparently survived with minimum damage. Plate IV located in the upper right corner consist of metals and coatings mounted in an aluminum baseplate and covered with a thin aluminum coverplate that partially mask the specimen. Several of the coatings appear to have changed to a darker color and a light brown discoloration appears around the outer edges of the mounting plate and along the right edge of the coverplates. Plate V, in the right center section, contained thermal plastics and structural film configured into tensile and shear specimen. All

  20. LDEF (Postflight), AO171 : Solar-Array-Materials Passive LDEF Experiment, Tray A08

    NASA Technical Reports Server (NTRS)

    1990-01-01

    LDEF (Postflight), AO171 : Solar-Array-Materials Passive LDEF Experiment, Tray A08 EL-1994-00147 LDEF (Postflight), AO171 : Solar-Array-Materials Passive LDEF Experiment, Tray A08 The post flight photograph was taken in the SAEF II at KSC prior to removal of the experiment tray from the LDEF and shows the Solar Array Materials Passive LDEF Experiment (SAMPLE) on the LDEF. Six (6) plates of passive components, provided by various experiment organizations and designated plate I thru plate VI, are shown mounted in a three (3) inch deep LDEF peripheral tray. All six plates are aluminum and attach to the LDEF experiment tray with non-magnetic stainless steel fasteners. Plate I, located in the upper right corner, consist of a combination of solar cells with and without covers, solar cell modules and solar arrays assembled on the baseplate. Three of the four solar arrays are missing. Other components appear to be secure. Plate II in the top center section, has twenty seven (27) composite samples, carbon fiber and glass fiber, mounted on the baseplate. The composites appear to be intact with no physical damage. Plate III, in the upper left corner, consist of metallized and thin polymeric films (Kapton, Mylar, TEFLON® , white Tedlar,etc.). The thin films without protective coatings sustained significant damage and most were destroyed. The thin film specimen hanging by one end in the flight photograph is missing. The metallized film apparently survived the mission with minimum damage. Plate IV located in the lower right corner consist of metals and coatings mounted in an aluminum baseplate and covered with a thin aluminum coverplate that partially mask the specimen. Several of the coatings appear to have darkened and a unique pattern of light brown discoloration appears around the outer edges of the mounting plate and along the lower edge of the coverplates. Plate V, in the lower center section, contained thermal plastics and structural film configured into tensile and

  1. Silicon Heterojunction Solar Cells: Temperature Impact on Passivation and Performance

    SciTech Connect

    Seif, J.; Krishnamani, G.; Demaurex, B.; Martin de Nicholas, S.; Holm, N.; Ballif, C.; De Wolf, S.

    2015-03-23

    Photovoltaic devices deployed in the field can reach operation temperatures (T) as high as 90 °C [1]. Hence, their temperature coefficients (TC1) are of great practical importance as they determine their energy yield. In this study we concentrate on T-related lifetime variations of amorphous/crystalline interfaces and study their influence on the TCs of the individual solar cell parameters. We find that both the open-circuit voltage (Voc) and fill factor (FF) are influenced by these lifetime variations. However, this is only a minor effect compared to the dominant increase of the intrinsic carrier density and the related increase in dark saturation current density. Additionally, in this paper we will show that the TCVoc does not depend solely on the initial value of the Voc [2, 3], but that the structure of the device has to be considered as well.

  2. Enhanced Conversion Efficiency of Cu(In,Ga)Se2 Solar Cells via Electrochemical Passivation Treatment.

    PubMed

    Tsai, Hung-Wei; Thomas, Stuart R; Chen, Chia-Wei; Wang, Yi-Chung; Tsai, Hsu-Sheng; Yen, Yu-Ting; Hsu, Cheng-Hung; Tsai, Wen-Chi; Wang, Zhiming M; Chueh, Yu-Lun

    2016-03-01

    Defect control in Cu(In,Ga)Se2 (CIGS) materials, no matter what the defect type or density, is a significant issue, correlating directly to PV performance. These defects act as recombination centers and can be briefly categorized into interface recombination and Shockley-Read-Hall (SRH) recombination, both of which can lead to reduced PV performance. Here, we introduce an electrochemical passivation treatment for CIGS films that can lower the oxygen concentration at the CIGS surface as observed by X-ray photoelectron spectrometer analysis. Temperature-dependent J-V characteristics of CIGS solar cells reveal that interface recombination is suppressed and an improved rollover condition can be achieved following our electrochemical treatment. As a result, the surface defects are passivated, and the power conversion efficiency performance of the solar cell devices can be enhanced from 4.73 to 7.75%.

  3. Advanced passivation techniques for Si solar cells with high-κ dielectric materials

    SciTech Connect

    Geng, Huijuan; Hwang, Huey-Liang; Kyznetsov, Fedor A.; Smirnova, Tamara P.; Saraev, Andrey A.; Kaichev, Vasily V.

    2014-09-22

    Electronic recombination losses at the wafer surface significantly reduce the efficiency of Si solar cells. Surface passivation using a suitable thin dielectric layer can minimize the recombination losses. Herein, advanced passivation using simple materials (Al{sub 2}O{sub 3}, HfO{sub 2}) and their compounds H{sub (Hf)}A{sub (Al)}O deposited by atomic layer deposition (ALD) was investigated. The chemical composition of Hf and Al oxide films were determined by X-ray photoelectron spectroscopy (XPS). The XPS depth profiles exhibit continuous uniform dense layers. The ALD-Al{sub 2}O{sub 3} film has been found to provide negative fixed charge (−6.4 × 10{sup 11 }cm{sup −2}), whereas HfO{sub 2} film provides positive fixed charge (3.2 × 10{sup 12 }cm{sup −2}). The effective lifetimes can be improved after oxygen gas annealing for 1 min. I-V characteristics of Si solar cells with high-κ dielectric materials as passivation layers indicate that the performance is significantly improved, and ALD-HfO{sub 2} film would provide better passivation properties than that of the ALD-Al{sub 2}O{sub 3} film in this research work.

  4. Large resource development projects as markets for passive solar technologies. Final report

    SciTech Connect

    Roze-Benson, R V

    1980-12-01

    A basic premise of this study is that large resource development projects provide a major market opportunity for passive solar manufactured buildings. The primary objectives of the work are to document selected resource development projects and identify their potential housing needs and development schedules, to contact resource industry representatives and assess some of the processes and motivations behind their involvement in housing decisions, and to provide passive solar manufactured buildings producers with results of these steps as early initial market intelligence. The intent is to identify not only the industries, location of their planned projects, and their likely worker housing needs, but also the individuals involved in making housing-related decisions. The 56 identified projects are located within 18 states and cover 11 types of resources. The report documents individual projects, provides protections of total worker-related housing needs, and presents overviews of resource development company involvement in the new construction market. In addition, the report profiles three organizations that expressed a strong interest in implementing the use of low-cost passive solar manufactured buildings in resource-development-related activities.

  5. Advanced phase change materials and systems for solar passive heating and cooling of residential buildings

    SciTech Connect

    Salyer, I.O.; Sircar, A.K.; Dantiki, S.

    1988-01-01

    During the last three years under the sponsorship of the DOE Solar Passive Division, the University of Dayton Research Institute (UDRI) has investigated four phase change material (PCM) systems for utility in thermal energy storage for solar passive heating and cooling applications. From this research on the basis of cost, performance, containment, and environmental acceptability, we have selected as our current and most promising series of candidate phase change materials, C-15 to C-24 linear crystalline alkyl hydrocarbons. The major part of the research during this contract period was directed toward the following three objectives. Find, test, and develop low-cost effective phase change materials (PCM) that melt and freeze sharply in the comfort temperature range of 73--77{degree}F for use in solar passive heating and cooling of buildings. Define practical materials and processes for fire retarding plasterboard/PCM building products. Develop cost-effective methods for incorporating PCM into building construction materials (concrete, plasterboard, etc.) which will lead to the commercial manufacture and sale of PCM-containing products resulting in significant energy conservation.

  6. Building America Best Practices Series, Volume 6: High-Performance Home Technologies: Solar Thermal & Photovoltaic Systems

    SciTech Connect

    Baechler, Michael C.; Gilbride, Theresa L.; Ruiz, Kathleen A.; Steward, Heidi E.; Love, Pat M.

    2007-06-04

    This guide is was written by PNNL for the US Department of Energy's Building America program to provide information for residential production builders interested in building near zero energy homes. The guide provides indepth descriptions of various roof-top photovoltaic power generating systems for homes. The guide also provides extensive information on various designs of solar thermal water heating systems for homes. The guide also provides construction company owners and managers with an understanding of how solar technologies can be added to their homes in a way that is cost effective, practical, and marketable. Twelve case studies provide examples of production builders across the United States who are building energy-efficient homes with photovoltaic or solar water heating systems.

  7. Solar Successes: The Best of Today's Energy Efficient Homes (Fact Sheet)

    SciTech Connect

    Not Available

    2008-01-01

    This is a brochure developed specifically for residential home builders. It provides information on basic financial factors and additional resources to consider when incorporating solar technologies into building plans.

  8. Diffusion-free back contact solar cells on sulfur-passivated silicon(100) substrates

    NASA Astrophysics Data System (ADS)

    Song, Guanghua

    A diffusion-free back contact solar cell is proposed in this work. The textured front-side of this cell is coated with ˜100 nm thermal SiO2 to enhance the light trapping meanwhile reduce the surface recombination velocity (SRV). The back-side of this cell is finger-patterned, using a diffusion-free junction as its emitter region and Al-Si alloy as its base contact. The diffusion-free junction is made by a Schottky contact between low work-function metal aluminum (Al) and sulfur (S)-passivated p-type Si(100) surface. Solution-based S passivation is one of the experimental realizations of the "valence-mending concept". Previously developed MBE (molecular bean epitaxy) selenium (Se) passivation is not used due to its time-consuming process and high energy input. Following the concept, passivation of Si(100) surface by Group VI elements such as S and Se terminates the dangling bonds and releases the strained bonds and dimer bonds, thus significantly reduces the surface states. Quantification of surface states or interface states is introduced through the nano-CMOS devices. Removal of surface states enables an almost ideal barrier height after metal contact. This is one of the methods achieving the high Schottky barrier. Al on S-passivated p-type Si(100) surface yields an extremely high Schottky barrier of 1.1 eV, about 0.2 eV higher than the corresponding ideal barrier height. This discrepancy is accounted by S-Si dipole moment on the surface. Calculations using Fermi statistics discloses that the barrier height of 1.1 eV causes the degenerate inversion on Si surface, making this Schottky junction electrically behave like a diffused p-n junction. Eventually this junction as a field-induced junction free of any diffusion is integrated in the fabrication of the proposed back contact solar cells. High work-function metal Platinum (Pt) and nickel (Ni) on S-passivated n-type Si(100) are also investigated, but the yielding barrier heights are not high enough to create

  9. Aluminum oxide passivated radial junction sub-micrometre pillar array textured silicon solar cells

    NASA Astrophysics Data System (ADS)

    Pudasaini, Pushpa Raj; Elam, David; Ayon, Arturo A.

    2013-06-01

    We report radial, p-n junction, sub-micrometre, pillar array textured solar cells, fabricated on an n-type Czochralski silicon wafer. Relatively simple processing schemes such as metal-assisted chemical etching and spin on dopant techniques were employed for the fabrication of the proposed solar cells. Atomic layer deposition (ALD) grown aluminum oxide (Al2O3) was employed as a surface passivation layer on the B-doped emitter surface. In spite of the fact that the sub-micrometre pillar array textured surface has a relatively high surface-to-volume ratio, we observed an open circuit voltage (VOC) and a short circuit current density (JSC) as high as 572 mV and 29.9 mA cm-2, respectively, which leads to a power conversion efficiency in excess of 11.30%, for the optimized structure of the solar cell described herein. Broadband omnidirectional antireflection effects along with the light trapping property of the sub-micrometre, pillar array textured surface and the excellent passivation quality of the ALD-grown Al2O3 on the B-doped emitter surface were responsible for the enhanced electrical performance of the proposed solar cells.

  10. Improved performance due to selective passivation of nitrogen clusters in GaInNAs solar cells

    NASA Astrophysics Data System (ADS)

    Fukuda, Miwa; Whiteside, Vincent R.; Al Khalfioui, Mohamed; Leroux, Mathieu; Hossain, Khalid; Sellers, Ian R.

    2015-03-01

    While GaInNAs has the potential to be a fourth-junction in multi-junction solar cells it has proved to be difficult to incorporate due to the low solubility of nitrogen in these materials. Specifically, mid-gap states attributed to nitrogen clusters have proved prohibitive for practical implementation of these systems. Here, we present the selective passivation of nitrogen impurities using a UV-activated hydrogenation process, which enables the removal of defects while retaining substitution nitrogen. Temperature dependent photoluminescence measurements of the intrinsic region of a GaInNAs p-i-n solar cell show a classic ``s-shape'' associated with localization prior to hydrogenation, while after hydrogenation no sign of the ``s-shape'' is evident. This passivation of nitrogen centers is reflected in improved performance of solar cells structures relative to reference, unpassivated devices presenting a potential route to practical implementation of GaInNAs solar cells. The authors acknowledge support through Oklahoma Center for the Advancement of Science and Technology under the Oklahoma Applied Research Support Grant No. AR12.2-040.

  11. Heating Unsaturated Sediments Using Solar Energy to Enhance Passive Sediment Remediation Technologies

    NASA Astrophysics Data System (ADS)

    Rossman, A.

    2002-12-01

    Sediment heating has been shown to enhance passive sediment remediation technologies such as bioremediation and barometric pumping (passive soil venting). Sediment heating raises the slow remediation rates that often limit the widespread use of these technologies. In bioremediation applications, a 10 degree C increase in subsurface temperature is expected to double the microbial activity, and thus the remediation rate. The removal rate of tetracholorethylene (PCE - a common subsurface contaminant) by passive soil vapor extraction is expected to nearly double in low-permeable sediments when the subsurface is heated 10 degree C from ambient temperatures due to an increased vapor pressure in the PCE. When the sediment is heated using renewable energy sources, these thermally enhanced remediation technologies can be environmentally benign alternatives to conventional remediation techniques that rely on large external energy inputs. The thermally enhanced passive technologies may be particularly useful for remediating unsaturated, low-permeable lenses that are troublesome to most conventional remediation technologies such as conventional soil vapor extraction and co-solvent flushes. The main objective of this work was to quantify subsurface sediment heating using a solar powered heat injection well. To do this, a pilot sediment heating system was installed in Vermont and high resolution meteorological and sediment temperature data were collected using a stand-alone data acquisition system. Unsaturated, silty sediments were heated in-situ by converting the direct and indirect solar energy available at the surface to heat energy in the subsurface using stand-alone renewable energy sources and a resistive element heat injection well. The heat injection well was powered by a 600-W passively tracking photovoltaic (PV) array and a small 1.2-m swept area wind turbine. It is envisioned that the heat injection well would be placed directly into an area of high subsurface

  12. Attached-sunspace passive solar-heated residences: A study of nationwide patterns of economic feasibility for the existing housing stock

    NASA Astrophysics Data System (ADS)

    Roach, F.; Kirschner, C.

    1981-06-01

    Performance estimates for attached-sunspace passive solar-heated residences were incorporated into the Los Alamos/UNM EASE 3 Model. These estimates are used to analyze the economic performance of a passive sunspace design when retrofitting onto an existing single-family home. Several key parameters are evaluated, including loan or mortgage terms, ownership period, resale potential, and competing conventional fuel prices. General economic and design parameters are combined in one version of life-cycle costing to evaluate the feasibility of both owner-built and contractor-built attached sunspaces for 220 regions in the contiguous US. The conventional fuel alternatives are natural gas, heating oil, electric resistance, and electric heat pump. The optimal sunspace design in determined for the fuel alternatives by minimizing the combined solar and conventional delivered cost of heat. An analysis of fuel used for space heating in existing homes is used to discuss the retrofit potential for the 220 regions. Results show that the prospect for conventional fuel displacement through retrofit of attached sunspace is very good, and that the design's economic performance is enhanced in regions with expensive conventional fuel alternatives.

  13. Passive acoustic telemetry reveals highly variable home range and movement patterns among unicornfish within a marine reserve

    NASA Astrophysics Data System (ADS)

    Marshell, A.; Mills, J. S.; Rhodes, K. L.; McIlwain, J.

    2011-09-01

    Marine reserves are the primary management tool for Guam's reef fish fishery. While a build-up of fish biomass has occurred inside reserve boundaries, it is unknown whether reserve size matches the scale of movement of target species. Using passive acoustic telemetry, we quantified movement patterns and home range size of two heavily exploited unicornfish Naso unicornis and Naso lituratus. Fifteen fish ( N. unicornis: n = 7; N. lituratus: n = 4 male, n = 4 female) were fitted with internal acoustic tags and tracked continuously over four months within a remote acoustic receiver array located in a decade-old marine reserve. This approach provided robust estimates of unicornfish movement patterns and home range size. The mean home range of 3.2 ha for N. unicornis was almost ten times larger than that previously recorded from a three-week tracking study of the species in Hawaii. While N. lituratus were smaller in body size, their mean home range (6.8 ha) was over twice that of N. unicornis. Both species displayed strong site fidelity, particularly during nocturnal and crepuscular periods. Although there was some overlap, individual movement patterns and home range size were highly variable within species and between sexes. N. unicornis home range increased with body size, and only the three largest fish home ranges extended into the deeper outer reef slope beyond the shallow reef flat. Both Naso species favoured habitat dominated by corals. Some individuals made predictable daily crepuscular migrations between different locations or habitat types. There was no evidence of significant spillover from the marine reserve into adjacent fished areas. Strong site fidelity coupled with negligible spillover suggests that small-scale reserves, with natural habitat boundaries to emigration, are effective in protecting localized unicornfish populations.

  14. Transparent electrodes in silicon heterojunction solar cells: Influence on contact passivation

    SciTech Connect

    Tomasi, Andrea; Sahli, Florent; Seif, Johannes Peter; Fanni, Lorenzo; de Nicolas Agut, Silvia Martin; Geissbuhler, Jonas; Paviet-Salomon, Bertrand; Nicolay, Sylvain; Barraud, Loris; Niesen, Bjoern; De Wolf, Stefaan; Ballif, Christophe

    2015-10-26

    Charge carrier collection in silicon heterojunction solar cells occurs via intrinsic/doped hydrogenated amorphous silicon layer stacks deposited on the crystalline silicon wafer surfaces. Usually, both the electron and hole collecting stacks are externally capped by an n-type transparent conductive oxide, which is primarily needed for carrier extraction. Earlier, it has been demonstrated that the mere presence of such oxides can affect the carrier recombination in the crystalline silicon absorber. Here, we present a detailed investigation of the impact of this phenomenon on both the electron and hole collecting sides, including its consequences for the operating voltages of silicon heterojunction solar cells. As a result, we define guiding principles for improved passivating contact design for high-efficiency silicon solar cells.

  15. Improved performance in GaInNAs solar cells by hydrogen passivation

    NASA Astrophysics Data System (ADS)

    Fukuda, M.; Whiteside, V. R.; Keay, J. C.; Meleco, A.; Sellers, I. R.; Hossain, K.; Golding, T. D.; Leroux, M.; Al Khalfioui, M.

    2015-04-01

    The effect of UV-activated hydrogenation on the performance of GaInNAs solar cells is presented. A proof-of-principle investigation was performed on non-optimum GaInNAs cells, which allowed a clearer investigation of the role of passivation on the intrinsic nitrogen-related defects in these materials. Upon optimized hydrogenation of GaInNAs, a significant reduction in the presence of defect and impurity based luminescence is observed as compared to that of unpassivated reference material. This improvement in the optical properties is directly transferred to an improved performance in solar cell operation, with a more than two-fold improvement in the external quantum efficiency and short circuit current density upon hydrogenation. Temperature dependent photovoltaic measurements indicate a strong contribution of carrier localization and detrapping processes, with non-radiative processes dominating in the reference materials, and evidence for additional strong radiative losses in the hydrogenated solar cells.

  16. Improved performance in GaInNAs solar cells by hydrogen passivation

    SciTech Connect

    Fukuda, M.; Whiteside, V. R.; Keay, J. C.; Meleco, A.; Sellers, I. R.; Hossain, K.; Golding, T. D.; Leroux, M.; Al Khalfioui, M.

    2015-04-06

    The effect of UV-activated hydrogenation on the performance of GaInNAs solar cells is presented. A proof-of-principle investigation was performed on non-optimum GaInNAs cells, which allowed a clearer investigation of the role of passivation on the intrinsic nitrogen-related defects in these materials. Upon optimized hydrogenation of GaInNAs, a significant reduction in the presence of defect and impurity based luminescence is observed as compared to that of unpassivated reference material. This improvement in the optical properties is directly transferred to an improved performance in solar cell operation, with a more than two-fold improvement in the external quantum efficiency and short circuit current density upon hydrogenation. Temperature dependent photovoltaic measurements indicate a strong contribution of carrier localization and detrapping processes, with non-radiative processes dominating in the reference materials, and evidence for additional strong radiative losses in the hydrogenated solar cells.

  17. Control system analysis for off-peak auxiliary heating of passive solar systems

    SciTech Connect

    Murray, H.S.; Melsa, J.L.; Balcomb, J.D.

    1980-01-01

    A computer simulation method is presented for the design of an electrical auxiliary energy system for passive solar heated structures. The system consists of electrical mats buried in the ground underneath the structure. Energy is stored in the ground during utility off-peak hours and released passively to the heated enclosure. An optimal control strategy is used to determine the system design parameters of depth of mat placement and minimum instaled electrical heating capacity. The optimal control applies combinations of fixed duration energy pulses to the heater, which minimize the room temperature error-squared for each day, assuming advance knowledge of the day's weather. Various realizable control schemes are investigated in an attempt to find a system that approaches the performance of the optimal control system.

  18. Rear passivation of commercial multi-crystalline PERC solar cell by PECVD Al2O3

    NASA Astrophysics Data System (ADS)

    Zhao, Suxiang; Qiao, Qi; Zhang, Song; Ji, Jingjia; Shi, Zhengrong; Li, Guohua

    2014-01-01

    Low-cost high-efficiency solar cells are the key to achieve grid parity with photovoltaic devices. Multi-crystalline silicon (mc-Si) solar cells are low-cost but low-efficiency. High-quality rear passivation is essential for the achievement of this goal. This dielectric stack, in conjunction with a local back surface field, produced mc-Si passivated emitter and rear cell (PERC) which efficiency exceeded 18.6%. The peak efficiency of 18.63% was achieved with Jsc of 37.44 mA/cm2 and Voc of 638 mV on commercial grade mc-Si wafers. Detailed characterization and modeling revealed that the increase in Voc and Jsc is the result of increased back surface reflectance from 74.8% to 90.7% and reduced back surface recombination velocity from 1800 to 260 cm/s. It was observed that the efficiency of mc-Si PERC solar cells decreased in degradation experiment.

  19. Notes on home-type solar hot water economics

    SciTech Connect

    Drumheller, K.

    1984-01-01

    Some things to consider before buying a solar hot water system is first discussed. Approximate savings in energy costs for a family of four with a solar hot water system are given. Buying a solar hot water system with money taken out of a savings account and with money borrowed on a bank card is next discussed. Finally, some comments are given on tracking parabolic through solar collectors vs flat plate collectors for residential systems.

  20. Antireflection and SiO2 Surface Passivation by Liquid-Phase Chemistry for Efficient Black Silicon Solar Cells: Preprint

    SciTech Connect

    Yuan, H. C.; Oh, J.; Zhang, Y.; Kuznetsov, O. A.; Flood, D. J.; Branz, H. M.

    2012-06-01

    We report solar cells with both black Si antireflection and SiO2 surface passivation provided by inexpensive liquid-phase chemistry, rather than by conventional vacuum-based techniques. Preliminary cell efficiency has reached 16.4%. Nanoporous black Si antireflection on crystalline Si by aqueous etching promises low surface reflection for high photon utilization, together with lower manufacturing cost compared to vacuum-based antireflection coating. Ag-nanoparticle-assisted black Si etching and post-etching chemical treatment recently developed at NREL enables excellent control over the pore diameter and pore separation. Performance of black Si solar cells, including open-circuit voltage, short-circuit current density, and blue response, has benefited from these improvements. Prior to this study, our black Si solar cells were all passivated by thermal SiO2 produced in tube furnaces. Although this passivation is effective, it is not yet ideal for ultra-low-cost manufacturing. In this study, we report, for the first time, the integration of black Si with a proprietary liquid-phase deposition (LPD) passivation from Natcore Technology. The Natcore LPD forms a layer of <10-nm SiO2 on top of the black Si surface in a relatively mild chemical bath at room temperature. We demonstrate black Si solar cells with LPD SiO2 with a spectrum-weighted average reflection lower than 5%, similar to the more costly thermally grown SiO2 approach. However, LPD SiO2 provides somewhat better surface-passivation quality according to the lifetime analysis by the photo-conductivity decay measurement. Moreover, black Si solar cells with LPD SiO2 passivation exhibit higher spectral response at short wavelength compared to those passivated by thermally grown SiO2. With further optimization, the combination of aqueous black Si etching and LPD could provide a pathway for low-cost, high-efficiency crystalline Si solar cells.

  1. Solar energy education. Renewable energy activities for general science

    SciTech Connect

    Not Available

    1985-01-01

    Renewable energy topics are integrated with the study of general science. The literature is provided in the form of a teaching manual and includes such topics as passive solar homes, siting a home for solar energy, and wind power for the home. Other energy topics are explored through library research activities. (BCS)

  2. Passive solar-heating retrofit of a maintenance facility: First-year performance

    NASA Astrophysics Data System (ADS)

    Jackson, D. R.; Callahan, J. M.

    1982-09-01

    A 12,000 sf maintenance facility in Connecticut was retrofitted with a 1,500 sf passive solar Trombe wall, 2 in. of foam roof insulation and a new control system that allows night/weekend temperature setback. A new separate boiler was installed to heat an office/locker wing of the facility. An energy-consumption monitoring system was installed and collected data for 11/2 years before the retrofit and one complete year after the retrofit. Actual energy consumption for the facility was very close to that predicted using simple analytic methods. After the solar wall was installed and other energy-conservation measures implemented the yearly oil consumption was reduced to 2744 gallons/year.

  3. Transparent electrodes in silicon heterojunction solar cells: Influence on contact passivation

    DOE PAGES

    Tomasi, Andrea; Sahli, Florent; Seif, Johannes Peter; Fanni, Lorenzo; de Nicolas Agut, Silvia Martin; Geissbuhler, Jonas; Paviet-Salomon, Bertrand; Nicolay, Sylvain; Barraud, Loris; Niesen, Bjoern; et al

    2015-10-26

    Charge carrier collection in silicon heterojunction solar cells occurs via intrinsic/doped hydrogenated amorphous silicon layer stacks deposited on the crystalline silicon wafer surfaces. Usually, both the electron and hole collecting stacks are externally capped by an n-type transparent conductive oxide, which is primarily needed for carrier extraction. Earlier, it has been demonstrated that the mere presence of such oxides can affect the carrier recombination in the crystalline silicon absorber. Here, we present a detailed investigation of the impact of this phenomenon on both the electron and hole collecting sides, including its consequences for the operating voltages of silicon heterojunction solarmore » cells. As a result, we define guiding principles for improved passivating contact design for high-efficiency silicon solar cells.« less

  4. Silicon heterojunction solar cell with passivated hole selective MoOx contact

    NASA Astrophysics Data System (ADS)

    Battaglia, Corsin; de Nicolás, Silvia Martín; De Wolf, Stefaan; Yin, Xingtian; Zheng, Maxwell; Ballif, Christophe; Javey, Ali

    2014-03-01

    We explore substoichiometric molybdenum trioxide (MoOx, x < 3) as a dopant-free, hole-selective contact for silicon solar cells. Using an intrinsic hydrogenated amorphous silicon passivation layer between the oxide and the silicon absorber, we demonstrate a high open-circuit voltage of 711 mV and power conversion efficiency of 18.8%. Due to the wide band gap of MoOx, we observe a substantial gain in photocurrent of 1.9 mA/cm2 in the ultraviolet and visible part of the solar spectrum, when compared to a p-type amorphous silicon emitter of a traditional silicon heterojunction cell. Our results emphasize the strong potential for oxides as carrier selective heterojunction partners to inorganic semiconductors.

  5. Silicon heterojunction solar cell with passivated hole selective MoO{sub x} contact

    SciTech Connect

    Battaglia, Corsin; Yin, Xingtian; Zheng, Maxwell; Javey, Ali; Martín de Nicolás, Silvia; De Wolf, Stefaan; Ballif, Christophe

    2014-03-17

    We explore substoichiometric molybdenum trioxide (MoO{sub x}, x < 3) as a dopant-free, hole-selective contact for silicon solar cells. Using an intrinsic hydrogenated amorphous silicon passivation layer between the oxide and the silicon absorber, we demonstrate a high open-circuit voltage of 711 mV and power conversion efficiency of 18.8%. Due to the wide band gap of MoO{sub x}, we observe a substantial gain in photocurrent of 1.9 mA/cm{sup 2} in the ultraviolet and visible part of the solar spectrum, when compared to a p-type amorphous silicon emitter of a traditional silicon heterojunction cell. Our results emphasize the strong potential for oxides as carrier selective heterojunction partners to inorganic semiconductors.

  6. Improved PEDOT:PSS/c-Si hybrid solar cell using inverted structure and effective passivation

    NASA Astrophysics Data System (ADS)

    Zhang, Xisheng; Yang, Dong; Yang, Zhou; Guo, Xiaojia; Liu, Bin; Ren, Xiaodong; Liu, Shengzhong (Frank)

    2016-10-01

    The PEDOT:PSS is often used as the window layer in the normal structured PEDOT:PSS/c-Si hybrid solar cell (HSC), leading to significantly reduced response, especially in red and near-infrared region. By depositing the PEDOT:PSS on the rear side of the c-Si wafer, we developed an inverted structured HSC with much higher solar cell response in the red and near-infrared spectrum. Passivating the other side with hydrogenated amorphous silicon (a-Si:H) before electrode deposition, the minority carrier lifetime has been significantly increased and the power conversion efficiency (PCE) of the inverted HSC is improved to as high as 16.1% with an open-circuit voltage (Voc) of 634 mV, fill factor (FF) of 70.5%, and short-circuit current density (Jsc) of 36.2 mA cm‑2, an improvement of 33% over the control device. The improvements are ascribed to inverted configuration and a-Si:H passivation, which can increase photon carrier generation and reduce carrier recombination, respectively. Both of them will benefit the photovoltaic performance and should be considered as effective design strategies to improve the performance of organic/c-Si HSCs.

  7. Materials research for passive solar systems: solid-state phase-change materials

    SciTech Connect

    Benson, D.K.; Webb, J.D.; Burrows, R.W.; McFadden, J.D.O.; Christensen, C.

    1985-03-01

    A set of solid-state phase-change materials is being evaluated for possible use in passive solar thermal energy storage systems. The most promising materials are organic solid solutions of pentaerythritol (C/sub 5/H/sub 12/O/sub 4/), pentaglycerinve (C/sub 5/H/sub 12/O/sub 3/), and neopentyl glycol (C/sub 5/H/sub 12/O/sub 2/). Solid solution mixtures of these compounds can be tailored so that they exhibit solid-to-solid phase transformations at any desired temperature betweeen 25/sup 0/C and 188/sup 0/C, and have latent heats of transformation between 20 and 70 cal/g. Transformation temperatures, specific heats, and latent heats of transformation have been measured for a number of these materials. Limited cyclic experiments suggest that the solid solutions are stable. These phase-change materials exhibit large amounts of undercooling; however, the addition of certain nucleating agents as particulate dispersions in the solid phase-change material greatly reduces this effect. Computer simulations suggest that the use of an optimized solid-state phase-change material in a Trombe wall could provide better performance than a concrete Trombe wall four times thicker and nine times heavier. Nevertheless, a higher cost of the phase-change materials (approx. =$0.70 per pound) is likely to limit their applicability in passive solar systems unless their performance can be significantly improved through further research.

  8. Improved PEDOT:PSS/c-Si hybrid solar cell using inverted structure and effective passivation

    PubMed Central

    Zhang, Xisheng; Yang, Dong; Yang, Zhou; Guo, Xiaojia; Liu, Bin; Ren, Xiaodong; Liu, Shengzhong (Frank)

    2016-01-01

    The PEDOT:PSS is often used as the window layer in the normal structured PEDOT:PSS/c-Si hybrid solar cell (HSC), leading to significantly reduced response, especially in red and near-infrared region. By depositing the PEDOT:PSS on the rear side of the c-Si wafer, we developed an inverted structured HSC with much higher solar cell response in the red and near-infrared spectrum. Passivating the other side with hydrogenated amorphous silicon (a-Si:H) before electrode deposition, the minority carrier lifetime has been significantly increased and the power conversion efficiency (PCE) of the inverted HSC is improved to as high as 16.1% with an open-circuit voltage (Voc) of 634 mV, fill factor (FF) of 70.5%, and short-circuit current density (Jsc) of 36.2 mA cm−2, an improvement of 33% over the control device. The improvements are ascribed to inverted configuration and a-Si:H passivation, which can increase photon carrier generation and reduce carrier recombination, respectively. Both of them will benefit the photovoltaic performance and should be considered as effective design strategies to improve the performance of organic/c-Si HSCs. PMID:27725714

  9. Amorphous Silicon Carbide Passivating Layers to Enable Higher Processing Temperature in Crystalline Silicon Heterojunction Solar Cells

    SciTech Connect

    Boccard, Mathieu; Holman, Zachary

    2015-04-06

    "Very efficient crystalline silicon (c-Si) solar cells have been demonstrated when thin layers of intrinsic and doped hydrogenated amorphous silicon (a-Si:H) are used for passivation and carrier selectivity in a heterojunction device. One limitation of this device structure is the (parasitic) absorption in the front passivation/collection a-Si:H layers; another is the degradation of the a-Si:H-based passivation upon temperature, limiting the post-processes to approximately 200°C thus restricting the contacting possibilities and potential tandem device fabrication. To alleviate these two limitations, we explore the potential of amorphous silicon carbide (a-SiC:H), a widely studied material in use in standard a-Si:H thin-film solar cells, which is known for its wider bandgap, increased hydrogen content and stronger hydrogen bonding compared to a-Si:H. We study the surface passivation of solar-grade textured n-type c-Si wafers for symmetrical stacks of 10-nm-thick intrinsic a-SiC:H with various carbon content followed by either p-doped or n-doped a-Si:H (referred to as i/p or i/n stacks). For both doping types, passivation (assessed through carrier lifetime measurements) is degraded by increasing the carbon content in the intrinsic a-SiC:H layer. Yet, this hierarchy is reversed after annealing at 350°C or more due to drastic passivation improvements upon annealing when an a-SiC:H layer is used. After annealing at 350°C, lifetimes of 0.4 ms and 2.0 ms are reported for i/p and i/n stacks, respectively, when using an intrinsic a-SiC:H layer with approximately 10% of carbon (initial lifetimes of 0.3 ms and 0.1 ms, respectively, corresponding to a 30% and 20-fold increase, respectively). For stacks of pure a-Si:H material the lifetimes degrade from 1.2 ms and 2.0 ms for i/p and i/n stacks, respectively, to less than 0.1 ms and 1.1 ms (12-fold and 2-fold decrease, respectively). For complete solar cells using pure a-Si:H i/p and i/n stacks, the open-circuit voltage (Voc

  10. Stevens Home, Rancho Santa Fe, California: Solar-energy-system performance evaluation, Oct. 1981 - Apr. 1982

    NASA Astrophysics Data System (ADS)

    Wetzel, P. E.

    Performance data on a solar water heating system are given. The Stevens Home in Califorina is a single family residence whose active solar energy system is designed to supply 70% of the hot water load. The system is equipped with 68 square feet of flat plate collectors, a 120 gallon solar preheat water tank, and a 40 gallon propane water heater. The solar fraction predicted by computer simulation and measured were the same, 44%. The system solar savings ratio, conventional fuel savings, and solar system coefficient of performance for the period covered are given. Monthly performance data are tabulated for the overall system and for the collector, storage, and domestic hot water subsystems. System operation is illustrated for a typical day by graphs of the temperatures at collector array, inlet and outlet, and at the preheat tank, and of water consumption. The typical operating sequence and solar energy use and heat losses are also graphed.

  11. Demonstration PreFab Solar Heated Vacation Home

    ERIC Educational Resources Information Center

    Ariola, Frank; Walencik, Vincent J.

    1978-01-01

    To update a traditional construction shop program, students at Passaic Valley High School, New Jersey, developed a mock-up model of a solar-heated A-frame vacation house using prefab construction. The article describes the project and illustrates it with photographs of the model and a drawing of the solar collector. (MF)

  12. Introduction to solar greenhouses: using the sun for home heating

    SciTech Connect

    Not Available

    1981-01-01

    The pictures and captions in this photographic essay are not a step-by-step plan to build a greenhouse, but are simply examples of major construction points in most solar greenhouses. A list of publications covering all aspects of solar greenhouses is included.

  13. Solar for Your Present Home. San Francisco Bay Area Edition.

    ERIC Educational Resources Information Center

    Barnaby, Charles S.; And Others

    This publication provides information about present uses of solar energy for space, water, and swimming pool heating that are practical for the San Francisco Bay area. It attempts to provide interested persons with the information needed to make decisions regarding installations of solar heating systems. The point of view taken is that any…

  14. Solar flair.

    PubMed Central

    Manuel, John S

    2003-01-01

    Design innovations and government-sponsored financial incentives are making solar energy increasingly attractive to homeowners and institutional customers such as school districts. In particular, the passive solar design concept of daylighting is gaining favor among educators due to evidence of improved performance by students working in daylit classrooms. Electricity-generating photovoltaic systems are also becoming more popular, especially in states such as California that have high electric rates and frequent power shortages. To help spread the word about solar power, the U.S. Department of Energy staged its first-ever Solar Decathlon in October 2002. This event featured solar-savvy homes designed by 14 college teams. PMID:12573926

  15. Solar flair.

    PubMed

    Manuel, John S

    2003-02-01

    Design innovations and government-sponsored financial incentives are making solar energy increasingly attractive to homeowners and institutional customers such as school districts. In particular, the passive solar design concept of daylighting is gaining favor among educators due to evidence of improved performance by students working in daylit classrooms. Electricity-generating photovoltaic systems are also becoming more popular, especially in states such as California that have high electric rates and frequent power shortages. To help spread the word about solar power, the U.S. Department of Energy staged its first-ever Solar Decathlon in October 2002. This event featured solar-savvy homes designed by 14 college teams.

  16. Solar flair.

    PubMed

    Manuel, John S

    2003-02-01

    Design innovations and government-sponsored financial incentives are making solar energy increasingly attractive to homeowners and institutional customers such as school districts. In particular, the passive solar design concept of daylighting is gaining favor among educators due to evidence of improved performance by students working in daylit classrooms. Electricity-generating photovoltaic systems are also becoming more popular, especially in states such as California that have high electric rates and frequent power shortages. To help spread the word about solar power, the U.S. Department of Energy staged its first-ever Solar Decathlon in October 2002. This event featured solar-savvy homes designed by 14 college teams. PMID:12573926

  17. Hood River Passive House

    SciTech Connect

    Hales, David

    2014-01-01

    The Hood River Passive Project was developed by Root Design Build of Hood River Oregon using the Passive House Planning Package (PHPP) to meet all of the requirements for certification under the European Passive House standards. The Passive House design approach has been gaining momentum among residential designers for custom homes and BEopt modeling indicates that these designs may actually exceed the goal of the U.S. Department of Energy's (DOE) Building America program to "reduce home energy use by 30%-50% (compared to 2009 energy codes for new homes). This report documents the short term test results of the Shift House and compares the results of PHPP and BEopt modeling of the project. The design includes high R-Value assemblies, extremely tight construction, high performance doors and windows, solar thermal DHW, heat recovery ventilation, moveable external shutters and a high performance ductless mini-split heat pump. Cost analysis indicates that many of the measures implemented in this project did not meet the BA standard for cost neutrality. The ductless mini-split heat pump, lighting and advanced air leakage control were the most cost effective measures. The future challenge will be to value engineer the performance levels indicated here in modeling using production based practices at a significantly lower cost.

  18. Hood River Passive House

    SciTech Connect

    Hales, D.

    2014-01-01

    The Hood River Passive Project was developed by Root Design Build of Hood River Oregon using the Passive House Planning Package (PHPP) to meet all of the requirements for certification under the European Passive House standards. The Passive House design approach has been gaining momentum among residential designers for custom homes and BEopt modeling indicates that these designs may actually exceed the goal of the U.S. Department of Energy's (DOE) Building America program to reduce home energy use by 30%-50% (compared to 2009 energy codes for new homes). This report documents the short term test results of the Shift House and compares the results of PHPP and BEopt modeling of the project. The design includes high R-Value assemblies, extremely tight construction, high performance doors and windows, solar thermal DHW, heat recovery ventilation, moveable external shutters and a high performance ductless mini-split heat pump. Cost analysis indicates that many of the measures implemented in this project did not meet the BA standard for cost neutrality. The ductless mini-split heat pump, lighting and advanced air leakage control were the most cost effective measures. The future challenge will be to value engineer the performance levels indicated here in modeling using production based practices at a significantly lower cost.

  19. Infrared light management in high-efficiency silicon heterojunction and rear-passivated solar cells

    NASA Astrophysics Data System (ADS)

    Holman, Zachary C.; Filipič, Miha; Descoeudres, Antoine; De Wolf, Stefaan; Smole, Franc; Topič, Marko; Ballif, Christophe

    2013-01-01

    Silicon heterojunction solar cells have record-high open-circuit voltages but suffer from reduced short-circuit currents due in large part to parasitic absorption in the amorphous silicon, transparent conductive oxide (TCO), and metal layers. We previously identified and quantified visible and ultraviolet parasitic absorption in heterojunctions; here, we extend the analysis to infrared light in heterojunction solar cells with efficiencies exceeding 20%. An extensive experimental investigation of the TCO layers indicates that the rear layer serves as a crucial electrical contact between amorphous silicon and the metal reflector. If very transparent and at least 150 nm thick, the rear TCO layer also maximizes infrared response. An optical model that combines a ray-tracing algorithm and a thin-film simulator reveals why: parallel-polarized light arriving at the rear surface at oblique incidence excites surface plasmons in the metal reflector, and this parasitic absorption in the metal can exceed the absorption in the TCO layer itself. Thick TCO layers—or dielectric layers, in rear-passivated diffused-junction silicon solar cells—reduce the penetration of the evanescent waves to the metal, thereby increasing internal reflectance at the rear surface. With an optimized rear TCO layer, the front TCO dominates the infrared losses in heterojunction solar cells. As its thickness and carrier density are constrained by anti-reflection and lateral conduction requirements, the front TCO can be improved only by increasing its electron mobility. Cell results attest to the power of TCO optimization: With a high-mobility front TCO and a 150-nm-thick, highly transparent rear ITO layer, we recently reported a 4-cm2 silicon heterojunction solar cell with an active-area short-circuit current density of nearly 39 mA/cm2 and a certified efficiency of over 22%.

  20. Passive in-home measurement of stride-to-stride gait variability comparing vision and Kinect sensing.

    PubMed

    Stone, Erik E; Skubic, Marjorie

    2011-01-01

    We present an analysis of measuring stride-to-stride gait variability passively, in a home setting using two vision based monitoring techniques: anonymized video data from a system of two web-cameras, and depth imagery from a single Microsoft Kinect. Millions of older adults fall every year. The ability to assess the fall risk of elderly individuals is essential to allowing them to continue living safely in independent settings as they age. Studies have shown that measures of stride-to-stride gait variability are predictive of falls in older adults. For this analysis, a set of participants were asked to perform a number of short walks while being monitored by the two vision based systems, along with a marker based Vicon motion capture system for ground truth. Measures of stride-to-stride gait variability were computed using each of the systems and compared against those obtained from the Vicon.

  1. Optimisation of concentrating solar cell systems with passive and active cooling

    NASA Astrophysics Data System (ADS)

    Blumenberg, J.

    1983-10-01

    Design considerations for concentrator solar cell arrays for space applications are reviewed, noting the restrictions on total mass that govern system selections. Consideration is given to systems with parabolic mirrors and Si and GaAs solar cells. Passive and active cooling systems for the arrays are discussed, as is the addition of a heat engine with a turbogenerator to utilize part of the waste heat of the cooling cycle. Attention is given to systems orbiting at 0.5, 1, and 3.5 AU from the sun. Flat panels are found to be more suitable for missions near the sun for Si solar cells, while GaAs cells with concentration are preferred to flat panel systems at all distances from the sun. Nuclear turboelectric systems are better than concentrator Si arrays at large distances from the sun, in terms of specific masses of the systems. The addition of a system to use waste heat is judged unfavorable from specific mass factors.

  2. Quantitative Gait Measurement With Pulse-Doppler Radar for Passive In-Home Gait Assessment

    PubMed Central

    Skubic, Marjorie; Rantz, Marilyn; Cuddihy, Paul E.

    2014-01-01

    In this paper, we propose a pulse-Doppler radar system for in-home gait assessment of older adults. A methodology has been developed to extract gait parameters including walking speed and step time using Doppler radar. The gait parameters have been validated with a Vicon motion capture system in the lab with 13 participants and 158 test runs. The study revealed that for an optimal step recognition and walking speed estimation, a dual radar set up with one radar placed at foot level and the other at torso level is necessary. An excellent absolute agreement with intraclass correlation coefficients of 0.97 was found for step time estimation with the foot level radar. For walking speed, although both radars show excellent consistency they all have a system offset compared to the ground truth due to walking direction with respect to the radar beam. The torso level radar has a better performance (9% offset on average) in the speed estimation compared to the foot level radar (13%–18% offset). Quantitative analysis has been performed to compute the angles causing the systematic error. These lab results demonstrate the capability of the system to be used as a daily gait assessment tool in home environments, useful for fall risk assessment and other health care applications. The system is currently being tested in an unstructured home environment. PMID:24771566

  3. Quantitative gait measurement with pulse-Doppler radar for passive in-home gait assessment.

    PubMed

    Wang, Fang; Skubic, Marjorie; Rantz, Marilyn; Cuddihy, Paul E

    2014-09-01

    In this paper, we propose a pulse-Doppler radar system for in-home gait assessment of older adults. A methodology has been developed to extract gait parameters including walking speed and step time using Doppler radar. The gait parameters have been validated with a Vicon motion capture system in the lab with 13 participants and 158 test runs. The study revealed that for an optimal step recognition and walking speed estimation, a dual radar set up with one radar placed at foot level and the other at torso level is necessary. An excellent absolute agreement with intraclass correlation coefficients of 0.97 was found for step time estimation with the foot level radar. For walking speed, although both radars show excellent consistency they all have a system offset compared to the ground truth due to walking direction with respect to the radar beam. The torso level radar has a better performance (9% offset on average) in the speed estimation compared to the foot level radar (13%-18% offset). Quantitative analysis has been performed to compute the angles causing the systematic error. These lab results demonstrate the capability of the system to be used as a daily gait assessment tool in home environments, useful for fall risk assessment and other health care applications. The system is currently being tested in an unstructured home environment.

  4. Quantitative gait measurement with pulse-Doppler radar for passive in-home gait assessment.

    PubMed

    Wang, Fang; Skubic, Marjorie; Rantz, Marilyn; Cuddihy, Paul E

    2014-09-01

    In this paper, we propose a pulse-Doppler radar system for in-home gait assessment of older adults. A methodology has been developed to extract gait parameters including walking speed and step time using Doppler radar. The gait parameters have been validated with a Vicon motion capture system in the lab with 13 participants and 158 test runs. The study revealed that for an optimal step recognition and walking speed estimation, a dual radar set up with one radar placed at foot level and the other at torso level is necessary. An excellent absolute agreement with intraclass correlation coefficients of 0.97 was found for step time estimation with the foot level radar. For walking speed, although both radars show excellent consistency they all have a system offset compared to the ground truth due to walking direction with respect to the radar beam. The torso level radar has a better performance (9% offset on average) in the speed estimation compared to the foot level radar (13%-18% offset). Quantitative analysis has been performed to compute the angles causing the systematic error. These lab results demonstrate the capability of the system to be used as a daily gait assessment tool in home environments, useful for fall risk assessment and other health care applications. The system is currently being tested in an unstructured home environment. PMID:24771566

  5. Hydrogen passivation of defects and rapid thermal processing for high-efficiency silicon ribbon solar cells

    NASA Astrophysics Data System (ADS)

    Jeong, Ji-Weon

    2002-01-01

    The use of photovoltaic (PV) system offers a unique opportunity to solve the energy and the environmental problems simultaneously because solar energy is free and can be directly converted into electrical energy by solar cells without any undesirable impact on the environment. In spite of the many advantages, PV still accounts for less than 0.05% of the current U.S. energy portfolio. This is mainly because PV is 2-4 times more expensive than traditional energy sources. PV modules should cost about $1/W to produce electricity at a rate of 6¢/kWh and to compete with fossil fuels. Since Si material accounts for ˜40% of the cost of current Si PV modules, the use of low-cost Si substrate is critical for cost reduction. Edge-defined film-fed grown (EFG) Si ribbon is the focus as substrate materials for this research because it is one of the most promising for low-cost PV. However, as-grown EFG Si has a lot of impurities and crystal defects resulted from the Si feedstock and its growth system, which reduce the bulk lifetime of less than 3 ms. In this research, first, the requirements for achieving 16% efficiency have been established using computer model simulations. To improve the bulk lifetime, manufacturable P and Al gettering techniques are developed to remove the lifetime-killing impurities from the active to inactive device regions. PECVD SiN-induced hydrogen defect passivation is investigated and maximized through the fundamental understanding of the role of Al, the impact of RTP firing, and the difference between two PECVD SiN films. For low-cost contact formation, a novel RTP firing process is developed for high-quality screen-printed contacts and Al-BSF. Finally, a complete process sequence that involves the optimal conditions for defect passivation and contacts is developed to produce ˜16% efficiency on screen-printed EFG Si solar cells, which is the highest efficiency for any screen-printed Si ribbon solar cells to date.

  6. Investigation of surface passivation schemes for p-type monocrystalline silicon solar cell

    NASA Astrophysics Data System (ADS)

    Rahman, Md. Momtazur; Udoy, Ariful Banna

    2016-10-01

    This paper represents an experiment to analyze the dark saturation current densities of passivated surfaces for monocrystalline silicon solar cells. The samples are diffused at peak temperatures of 800-950 °C. Basically, symmetrical lifetime samples with different doping profiles are prepared with alkaline textured and saw damage etched (planar) surfaces. After POCl3 diffusion, the phosphorous silicate glass layers are removed in a wet chemical etching step. Several designs are chosen for the determination of the sheet resistance ( R sh), the concentration profile for excess charge carrier and the minority carrier effective lifetime of the diffused surfaces. The dark saturation current densities ( J o ) and the doping profiles are determined accordingly via quasi-steady state photoconductance decay measurement and electrochemical capacitance-voltage measurement. Three different passivation schemes are investigated as follows: silicon nitride (SiN x ) deposited by plasma-enhanced chemical vapor deposition (PECVD) technique, silicon-rich oxynitride (SiriO x N y ) capped with a PECVD SiN x layer, and thin thermally grown oxide, capped with a PECVD SiN x layer.

  7. Passive cooling with solar updraft and evaporative downdraft chimneys. Interim report, June 15, 1984--March 1, 1985

    SciTech Connect

    Mignon, G.V.; Cunningham, W.A.; Thompson, T.L.

    1985-12-31

    Computer models have been developed to describe the operation of both solar updraft and evaporative downdraft chimneys. Design studies are being conducted at the present time to use the towers for cooling an experimental, well instrumented, structure to study passive cooling in residential buildings. (MHR)

  8. Illuminating Solar Decathlon Homes: Exploring Next Generation Lighting Technology - Light Emitting Diodes

    SciTech Connect

    Gordon, Kelly L.; Gilbride, Theresa L.

    2008-05-22

    This report was prepared by PNNL for the US Department of Energy Building Technologies Program, Solid-State Lighting Program. The report will be provided to teams of university students who are building houses for the 2009 Solar Decathlon, a home design competition sponsored in part by DOE, to encourage teams to build totally solar powered homes. One aspect of the competition is lighting. This report provides the teams with information about LED lighting that can help them determine how they incorporate LED lighting into their homes. The report provides an overview of LED technology, a status of where LED technology is today, questions and answers about lighting quality, efficiency, lifetime etc.; numerous examples of LED products; and several weblinks for further research.

  9. High-Performance Home Technologies: Solar Thermal & Photovoltaic Systems

    SciTech Connect

    Baechler, M.; Gilbride, T.; Ruiz, K.; Steward, H.; Love, P.

    2007-06-01

    This document is the sixth volume of the Building America Best Practices Series. It presents information that is useful throughout the United States for enhancing the energy efficiency practices in the specific climate zones that are presented in the first five Best Practices volumes. It provides an introduction to current photovoltaic and solar thermal building practices. Information about window selection and shading is included.

  10. Toward a passive low-cost in-home gait assessment system for older adults.

    PubMed

    Wang, Fang; Stone, Erik; Skubic, Marjorie; Keller, James M; Abbott, Carmen; Rantz, Marilyn

    2013-03-01

    In this paper, we propose a webcam-based system for in-home gait assessment of older adults. A methodology has been developed to extract gait parameters including walking speed, step time, and step length from a 3-D voxel reconstruction, which is built from two calibrated webcam views. The gait parameters are validated with a GAITRite mat and a Vicon motion capture system in the laboratory with 13 participants and 44 tests, and again with GAITRite for 8 older adults in senior housing. Excellent agreement with intraclass correlation coefficients of 0.99 and repeatability coefficients between 0.7% and 6.6% was found for walking speed, step time, and step length given the limitation of frame rate and voxel resolution. The system was further tested with ten seniors in a scripted scenario representing everyday activities in an unstructured environment. The system results demonstrate the capability of being used as a daily gait assessment tool for fall risk assessment and other medical applications. Furthermore, we found that residents displayed different gait patterns during their clinical GAITRite tests compared to the realistic scenario, namely a mean increase of 21% in walking speed, a mean decrease of 12% in step time, and a mean increase of 6% in step length. These findings provide support for continuous gait assessment in the home for capturing habitual gait. PMID:24235111

  11. High reduction of interfacial charge recombination in colloidal quantum dot solar cells by metal oxide surface passivation

    NASA Astrophysics Data System (ADS)

    Chang, Jin; Kuga, Yuki; Mora-Seró, Iván; Toyoda, Taro; Ogomi, Yuhei; Hayase, Shuzi; Bisquert, Juan; Shen, Qing

    2015-03-01

    Bulk heterojunction (BHJ) solar cells based on colloidal QDs and metal oxide nanowires (NWs) possess unique and outstanding advantages in enhancing light harvesting and charge collection in comparison to planar architectures. However, the high surface area of the NW structure often brings about a large amount of recombination (especially interfacial recombination) and limits the open-circuit voltage in BHJ solar cells. This problem is solved here by passivating the surface of the metal oxide component in PbS colloidal quantum dot solar cells (CQDSCs). By coating thin TiO2 layers onto ZnO-NW surfaces, the open-circuit voltage and power conversion efficiency have been improved by over 40% in PbS CQDSCs. Characterization by transient photovoltage decay and impedance spectroscopy indicated that the interfacial recombination was significantly reduced by the surface passivation strategy. An efficiency as high as 6.13% was achieved through the passivation approach and optimization for the length of the ZnO-NW arrays (device active area: 16 mm2). All solar cells were tested in air, and exhibited excellent air storage stability (without any performance decline over more than 130 days). This work highlights the significance of metal oxide passivation in achieving high performance BHJ solar cells. The charge recombination mechanism uncovered in this work could shed light on the further improvement of PbS CQDSCs and/or other types of solar cells.Bulk heterojunction (BHJ) solar cells based on colloidal QDs and metal oxide nanowires (NWs) possess unique and outstanding advantages in enhancing light harvesting and charge collection in comparison to planar architectures. However, the high surface area of the NW structure often brings about a large amount of recombination (especially interfacial recombination) and limits the open-circuit voltage in BHJ solar cells. This problem is solved here by passivating the surface of the metal oxide component in PbS colloidal quantum dot solar

  12. Passive smoking at home is a risk factor for community-acquired pneumonia in older adults: a population-based case–control study

    PubMed Central

    Almirall, Jordi; Serra-Prat, Mateu; Bolíbar, Ignasi; Palomera, Elisabet; Roig, Jordi; Hospital, Imma; Carandell, Eugenia; Agustí, Mercè; Ayuso, Pilar; Estela, Andreu; Torres, Antoni

    2014-01-01

    Objective To assess whether passive smoking exposure at home is a risk factor for community-acquired pneumonia (CAP) in adults. Setting A population-based case-control study was designed in a Mediterranean area with 860 000 inhabitants >14 years of age. Participants 1003 participants who had never smoked were recruited. Primary and secondary outcome measures Risk factors for CAP, including home exposure to passive smoking, were registered. All new cases of CAP in a well-defined population were consecutively recruited during a 12-month period. Methods A population-based case-control study was designed to assess risk factors for CAP, including home exposure to passive smoking. All new cases of CAP in a well-defined population were consecutively recruited during a 12-month period. The subgroup of never smokers was selected for the present analysis. Results The study sample included 471 patients with CAP and 532 controls who had never smoked. The annual incidence of CAP was estimated to be 1.14 cases×10–3 inhabitants in passive smokers and 0.90×10−3 in non-passive smokers (risk ratio (RR) 1.26; 95% CI 1.02 to 1.55) in the whole sample. In participants ≥65 years of age, this incidence was 2.50×10−3 in passive smokers and 1.69×10−3 in non-passive smokers (RR 1.48, 95% CI 1.08 to 2.03). In this last age group, the percentage of passive smokers in cases and controls was 26% and 18.1%, respectively (p=0.039), with a crude OR of 1.59 (95% CI 1.02 to 2.38) and an adjusted (by age and sex) OR of 1.56 (95% CI 1.00 to 2.45). Conclusions Passive smoking at home is a risk factor for CAP in older adults (65 years or more). PMID:24928592

  13. Tantalum oxide/silicon nitride: A negatively charged surface passivation stack for silicon solar cells

    SciTech Connect

    Wan, Yimao Bullock, James; Cuevas, Andres

    2015-05-18

    This letter reports effective passivation of crystalline silicon (c-Si) surfaces by thermal atomic layer deposited tantalum oxide (Ta{sub 2}O{sub 5}) underneath plasma enhanced chemical vapour deposited silicon nitride (SiN{sub x}). Cross-sectional transmission electron microscopy imaging shows an approximately 2 nm thick interfacial layer between Ta{sub 2}O{sub 5} and c-Si. Surface recombination velocities as low as 5.0 cm/s and 3.2 cm/s are attained on p-type 0.8 Ω·cm and n-type 1.0 Ω·cm c-Si wafers, respectively. Recombination current densities of 25 fA/cm{sup 2} and 68 fA/cm{sup 2} are measured on 150 Ω/sq boron-diffused p{sup +} and 120 Ω/sq phosphorus-diffused n{sup +} c-Si, respectively. Capacitance–voltage measurements reveal a negative fixed insulator charge density of −1.8 × 10{sup 12 }cm{sup −2} for the Ta{sub 2}O{sub 5} film and −1.0 × 10{sup 12 }cm{sup −2} for the Ta{sub 2}O{sub 5}/SiN{sub x} stack. The Ta{sub 2}O{sub 5}/SiN{sub x} stack is demonstrated to be an excellent candidate for surface passivation of high efficiency silicon solar cells.

  14. Isakson Home, Anoka, Minnesota solar-energy-system performance evaluation, Aug. 1981 - Mar. 1982

    NASA Astrophysics Data System (ADS)

    Cramer, M.

    1982-06-01

    Performance data on a residential solar water and space heating system are given. The Isakson Home in Minnesota is a single family residence whose active solar energy system is designed to supply 76% of the heating and hot water load. The system consists of 183 square feet of flat plate collectors, a 350 gallon water storage tank, and for back up, an oil fired furnace and 52 gallon electric water heater. Monthly performance data are given for the overall system and for the collector, domestic hot water, and space heating subsystem. Monthly data are also tabulated for the coefficient of performance, solar operating energy, energy savings, and weather. Typical system operation is illustrated by graphs of temperatures at various parts of the system versus time for a typical day, and by graphs of fuel use and hot water use versus time. The system operating sequence is also graphed and solar energy utilization and losses are given.

  15. Enhanced Lifetime of Polymer Solar Cells by Surface Passivation of Metal Oxide Buffer Layers.

    PubMed

    Venkatesan, Swaminathan; Ngo, Evan; Khatiwada, Devendra; Zhang, Cheng; Qiao, Qiquan

    2015-07-29

    The role of electron selective interfaces on the performance and lifetime of polymer solar cells were compared and analyzed. Bilayer interfaces consisting of metal oxide films with cationic polymer modification namely poly ethylenimine ethoxylated (PEIE) were found to enhance device lifetime compared to bare metal oxide films when used as an electron selective cathode interface. Devices utilizing surface-modified metal oxide layers showed enhanced lifetimes, retaining up to 85% of their original efficiency when stored in ambient atmosphere for 180 days without any encapsulation. The work function and surface potential of zinc oxide (ZnO) and ZnO/PEIE interlayers were evaluated using Kelvin probe and Kelvin probe force microscopy (KPFM) respectively. Kelvin probe measurements showed a smaller reduction in work function of ZnO/PEIE films compared to bare ZnO films when aged in atmospheric conditions. KPFM measurements showed that the surface potential of the ZnO surface drastically reduces when stored in ambient air for 7 days because of surface oxidation. Surface oxidation of the interface led to a substantial decrease in the performance in aged devices. The enhancement in the lifetime of devices with a bilayer interface was correlated to the suppressed surface oxidation of the metal oxide layers. The PEIE passivated surface retained a lower Fermi level when aged, which led to lower trap-assisted recombination at the polymer-cathode interface. Further photocharge extraction by linearly increasing voltage (Photo-CELIV) measurements were performed on fresh and aged samples to evaluate the field required to extract maximum charges. Fresh devices with a bare ZnO cathode interlayer required a lower field than devices with ZnO/PEIE cathode interface. However, aged devices with ZnO required a much higher field to extract charges while aged devices with ZnO/PEIE showed a minor increase compared to the fresh devices. Results indicate that surface modification can act as a

  16. A numerical simulation study of gallium-phosphide/silicon heterojunction passivated emitter and rear solar cells

    NASA Astrophysics Data System (ADS)

    Wagner, Hannes; Ohrdes, Tobias; Dastgheib-Shirazi, Amir; Puthen-Veettil, Binesh; König, Dirk; Altermatt, Pietro P.

    2014-01-01

    The performance of passivated emitter and rear (PERC) solar cells made of p-type Si wafers is often limited by recombination in the phosphorus-doped emitter. To overcome this limitation, a realistic PERC solar cell is simulated, whereby the conventional phosphorus-doped emitter is replaced by a thin, crystalline gallium phosphide (GaP) layer. The resulting GaP/Si PERC cell is compared to Si PERC cells, which have (i) a standard POCl3 diffused emitter, (ii) a solid-state diffused emitter, or (iii) a high efficiency ion-implanted emitter. The maximum efficiencies for these realistic PERC cells are between 20.5% and 21.2% for the phosphorus-doped emitters (i)-(iii), and up to 21.6% for the GaP emitter. The major advantage of this GaP hetero-emitter is a significantly reduced recombination loss, resulting in a higher Voc. This is so because the high valence band offset between GaP and Si acts as a nearly ideal minority carrier blocker. This effect is comparable to amorphous Si. However, the GaP layer can be contacted with metal fingers like crystalline Si, so no conductive oxide is necessary. Compared to the conventional PERC structure, the GaP/Si PERC cell requires a lower Si base doping density, which reduces the impact of the boron-oxygen complexes. Despite the lower base doping, fewer rear local contacts are necessary. This is so because the GaP emitter shows reduced recombination, leading to a higher minority electron density in the base and, in turn, to a higher base conductivity.

  17. A numerical simulation study of gallium-phosphide/silicon heterojunction passivated emitter and rear solar cells

    SciTech Connect

    Wagner, Hannes; Ohrdes, Tobias; Dastgheib-Shirazi, Amir; Puthen-Veettil, Binesh; König, Dirk; Altermatt, Pietro P.

    2014-01-28

    The performance of passivated emitter and rear (PERC) solar cells made of p-type Si wafers is often limited by recombination in the phosphorus-doped emitter. To overcome this limitation, a realistic PERC solar cell is simulated, whereby the conventional phosphorus-doped emitter is replaced by a thin, crystalline gallium phosphide (GaP) layer. The resulting GaP/Si PERC cell is compared to Si PERC cells, which have (i) a standard POCl{sub 3} diffused emitter, (ii) a solid-state diffused emitter, or (iii) a high efficiency ion-implanted emitter. The maximum efficiencies for these realistic PERC cells are between 20.5% and 21.2% for the phosphorus-doped emitters (i)–(iii), and up to 21.6% for the GaP emitter. The major advantage of this GaP hetero-emitter is a significantly reduced recombination loss, resulting in a higher V{sub oc}. This is so because the high valence band offset between GaP and Si acts as a nearly ideal minority carrier blocker. This effect is comparable to amorphous Si. However, the GaP layer can be contacted with metal fingers like crystalline Si, so no conductive oxide is necessary. Compared to the conventional PERC structure, the GaP/Si PERC cell requires a lower Si base doping density, which reduces the impact of the boron-oxygen complexes. Despite the lower base doping, fewer rear local contacts are necessary. This is so because the GaP emitter shows reduced recombination, leading to a higher minority electron density in the base and, in turn, to a higher base conductivity.

  18. Passivated Tunneling Contacts to N-Type Wafer Silicon and Their Implementation into High Performance Solar Cells: Preprint

    SciTech Connect

    Stradins, P.; Essig, S.; Nemeth, W.; Lee, B. G.; Young, D.; Norman, A.; Liu, Y.; Luo, J.-W.; Warren, E.; Dameron, A.; LaSalvia, V.; Page, M.; Rohatgi, A.; Upadhyaya, A.; Rounsaville, B.; Ok, Y.-W.; Glunz, S.; Benick, J.; Feldmann, F.; Hermle, M.

    2014-12-01

    We present a case that passivated contacts based on a thin tunneling oxide layer, combined with a transport layer with properly selected work function and band offsets, can lead to high efficiency c-Si solar cells. Passivated contacts contribute to cell efficiency as well as design flexibility, process robustness, and a simplified process flow. Material choices for the transport layer are examined, including transparent n-type oxides and n+-doped poly-Si. SiO2/n+-poly-Si full-area, induced-junction back surface field contacts to n-FZ and n-Cz Si are incorporated into high efficiency cells with deep, passivated boron emitters.

  19. The influence of passivation and photovoltaic properties of α-Si:H coverage on silicon nanowire array solar cells

    PubMed Central

    2013-01-01

    Silicon nanowire (SiNW) arrays for radial p-n junction solar cells offer potential advantages of light trapping effects and quick charge collection. Nevertheless, lower open circuit voltages (Voc) lead to lower energy conversion efficiencies. In such cases, the performance of the solar cells depends critically on the quality of the SiNW interfaces. In this study, SiNW core-shell solar cells have been fabricated by growing crystalline silicon (c-Si) nanowires via the metal-assisted chemical etching method and by depositing hydrogenated amorphous silicon (α-Si:H) via the plasma-enhanced chemical vapor deposition (PECVD) method. The influence of deposition parameters on the coverage and, consequently, the passivation and photovoltaic properties of α-Si:H layers on SiNW solar cells have been analyzed. PMID:24059343

  20. Thermal properties of masonry materials for passive-solar design: a state-of-the-art review. Final report

    SciTech Connect

    Van Geem, M.G.; Fiorato, A.E.

    1983-04-01

    This report summarizes available test data, evaluates test methods, and recommends values for thermal properties of masonry to be used in passive-solar design. Values of specific heat, conductivity, and diffusivity are given for concrete and clay brick. Variations of these values with other physical properties such as density, moisture content, and temperature are shown. Variations in data due to different test methods are analyzed. Values of absorptivity and emissivity for concrete and clay brick, and associated test methods, are also discussed.

  1. Economic implications of passive-solar retrofit for single-family residences in Albuquerque, New Mexico: A case study

    NASA Astrophysics Data System (ADS)

    Martin, S. W.

    1981-06-01

    Certain economic criteria are used to evaluate the potential of retrofitted passive solar systems. Actual system and labor costs along with calculated Input-Output income and employment multipliers are used to estimate changes in income and employment levels within the study area. Estimates of changing energy use patterns also are presented. The methodology presented can be expanded to include other technologies and can be used to examine other potential scenarios.

  2. Shellfish mariculture facility which employs passive solar heating and heat pump systems. Performance and cost analysis study. Final report

    SciTech Connect

    Zoto, G.A.; Krabach, M.H.

    1984-06-01

    This report incorporates operations data such as clam growth rates, clam biomass buildup, water volume, and algal food requirements compiled while developing a year-round production schedule for production of hard clam seed. The facility includes a passive solar hatchery and heat pump. Three major areas which affect development of energy-efficient mariculture are addressed: biological operation parameters, energy requirements, and system economics. (LEW)

  3. Design tool survey. IEA Solar Heating and Cooling - Task 8. Passive and hybrid solar low-energy buildings, Subtask C: design methods

    SciTech Connect

    Rittelmann, P.R.; Ahmed, S.F.

    1985-05-01

    This document presents the results of a survey of design tools conducted as part of Subtask C (Design Methods) of Task VIII of the IAE Solar Heating and Cooling Program. At the start of the task, the participants agreed that it would be useful to identify and characterize the various design tools which existed for predicting the energy performance of passive and hybrid solar low energy buildings. A standard survey form was adopted, and Subtask C representatives from the member countries collected and submitted information on the design tools in use in each country. These responses were compiled into the present survey document.

  4. Passive solar in Milton Keynes, England. A description of some of the more numerical aspects of the design of an estate of low energy houses

    NASA Astrophysics Data System (ADS)

    Everett, R.

    1980-07-01

    The numerical aspects of the design of low energy consumption houses using passive solar energy collection and high levels of insulation are described. Two housing energy conservation projects were begun, one involving the construction of 177 low energy houses on a cost-effective basis, and the other involving the detailed monitoring of eight highly insulated passive solar houses. Both experimental data and theoretical analysis are presented, and the relative effectiveness of the various design alternatives are discussed.

  5. Use of radiometer to reform and repair an old living house to passive solar one

    SciTech Connect

    Okamoto, Yoshizo; Inagaki, Terumi; Suzuki, Takakazu; Kurokawa, Takashi

    1994-12-31

    Japanese houses consist mainly of wooden elements under high-temperature and moist condition. To modify the hot and humid environment of the living room of one house, a conventional house was revamped and partially repaired. Especially for the winter season, a diagnostic thermographic test was used to detect deteriorated and leaking parts of interior and exterior walls. Macroscopic deteriorated parts were checked again in detail. The deteriorated element was replaced with a new one. During the reconstruction process, a new solar heat and air conditioning system using a silica-gel adsorber and underground water was installed to cool and warm up the living room. Thermography tests of this revamped house shows that room temperature is always constant and comfortable to human beings, especially in the winter. Temperature and heat flow distribution of flowing air in the living room was measured using thermal net and wire methods. Leaking thermal streak flow of the gap was locally visualized by the infrared radiometer and high-sensitive video camera. It was verified that the IR thermography is a useful measuring instrument to check thermal defects of the homes.

  6. Enhanced photoluminescence and solar cell performance via Lewis base passivation of organic-inorganic lead halide perovskites.

    PubMed

    Noel, Nakita K; Abate, Antonio; Stranks, Samuel D; Parrott, Elizabeth S; Burlakov, Victor M; Goriely, Alain; Snaith, Henry J

    2014-10-28

    Organic-inorganic metal halide perovskites have recently emerged as a top contender to be used as an absorber material in highly efficient, low-cost photovoltaic devices. Solution-processed semiconductors tend to have a high density of defect states and exhibit a large degree of electronic disorder. Perovskites appear to go against this trend, and despite relatively little knowledge of the impact of electronic defects, certified solar-to-electrical power conversion efficiencies of up to 17.9% have been achieved. Here, through treatment of the crystal surfaces with the Lewis bases thiophene and pyridine, we demonstrate significantly reduced nonradiative electron-hole recombination within the CH(3)NH(3)PbI(3-x)Cl(x) perovskite, achieving photoluminescence lifetimes which are enhanced by nearly an order of magnitude, up to 2 μs. We propose that this is due to the electronic passivation of under-coordinated Pb atoms within the crystal. Through this method of Lewis base passivation, we achieve power conversion efficiencies for solution-processed planar heterojunction solar cells enhanced from 13% for the untreated solar cells to 15.3% and 16.5% for the thiophene and pyridine-treated solar cells, respectively.

  7. Experimental study of the influence of collector height on the steady state performance of a passive solar air heater

    SciTech Connect

    Ryan, D.; Burek, S.A.M.

    2010-09-15

    Passive solar air heaters, such as solar chimneys and Trombe Walls, rely on solar-induced buoyancy-driven (natural) convection to produce the flow of air. Although buoyancy-driven convection is well understood for a single vertical plate, buoyancy-driven convection in an asymmetrically-heated channel is more problematic, and in particular, the effects of the channel height on the flow rate and heat transfer. This paper reports on experiments on test rigs resembling lightweight passive solar air-heating collectors. The test rigs were of heights 0.5, 1.0 and 2.0 m, with adjustable channel depths (20-150 mm) and heat inputs (up to 1000 W/m{sup 2}). Measurements were made of the air, plate and cover temperatures, and air velocities. Results are presented as dimensionless correlations of mass flow (as Reynolds number) and efficiency against heat input (as Rayleigh number), channel depth and height. Thermal efficiency is shown to be a function of the heat input and the system height, but not of the channel depth; mass flow is shown to be a dependent on all three parameters. (author)

  8. Surface passivated colloidal CuIn(S,Se)2 quantum dots for quantum dot heterojunction solar cells (Presentation Recording)

    NASA Astrophysics Data System (ADS)

    Yassitepe, Emre; Voznyy, Oleksandr; Sargent, Edward; Nogueira, Ana Flavia F.

    2015-10-01

    Colloidal quantum dot heterojunction thin film solar cells (CQD-TFSC) utilize facile thin film deposition methods and promise high photon conversion efficiencies (PCE) to cost ratio which is highly desired for commercialization. So far, surface passivated PbS CQD-TFSCs show the highest PCE results, reaching 9.2% with good stability. Among other potential candidates, CuInSe2 CQDs stand out as a non-toxic material with high potential for performance, judging on bulk Cu(Ga,In)(S,Se)2 TFSCs reaching 20% PCE, with high stability. CuInSe2 CQDs has advantage over bulk films, mainly the much less expensive manufacturing cost of uniform deposition on large areas. Ga is known to cause phase separation in the bulk CIGS system. In a CQD form, CuInSe2 band gap can be tuned between 1 to 1.6 eV by quantum confinement without need for Ga and this eliminates the phase separation issue. Within our best knowledge, there are no reports on surface trap passivated CuInSe2 CQD-TFSCs. However Cu(In,Ga)(S,Se)2 colloidal particles were cast in thin film form and fused to form bulk-like crystals by various annealing conditions for solar cell devices. In this work, we investigated well-passivated CuInSe2 CQDs on n-type TiO2 and ZnO layers to form depleted heterojunction structure. We prepared luminescent CuInSe2 CQDs by synthetic wet chemistry methods and passivated the surface with 3-mercaptopropionic acid or tetrabutylammonium iodide using solid-state ligand exchange. X-ray photoelectron spectroscopy was used to confirm the ligand boding and surface coverage of the quantum dots. We will present the effect of synthesis and thin film preparation conditions on the solar cell device performance

  9. Efficiency Enhancement of Nanotextured Black Silicon Solar Cells Using Al2O3/TiO2 Dual-Layer Passivation Stack Prepared by Atomic Layer Deposition.

    PubMed

    Wang, Wei-Cheng; Tsai, Meng-Chen; Yang, Jason; Hsu, Chuck; Chen, Miin-Jang

    2015-05-20

    In this study, efficient nanotextured black silicon (NBSi) solar cells composed of silicon nanowire arrays and an Al2O3/TiO2 dual-layer passivation stack on the n(+) emitter were fabricated. The highly conformal Al2O3 and TiO2 surface passivation layers were deposited on the high-aspect-ratio surface of the NBSi wafers using atomic layer deposition. Instead of the single Al2O3 passivation layer with a negative oxide charge density, the Al2O3/TiO2 dual-layer passivation stack treated with forming gas annealing provides a high positive oxide charge density and a low interfacial state density, which are essential for the effective field-effect and chemical passivation of the n(+) emitter. In addition, the Al2O3/TiO2 dual-layer passivation stack suppresses the total reflectance over a broad range of wavelengths (400-1000 nm). Therefore, with the Al2O3/TiO2 dual-layer passivation stack, the short-circuit current density and efficiency of the NBSi solar cell were increased by 11% and 20%, respectively. In conclusion, a high efficiency of 18.5% was achieved with the NBSi solar cells by using the n(+)-emitter/p-base structure passivated with the Al2O3/TiO2 stack.

  10. Efficiency Enhancement of Nanotextured Black Silicon Solar Cells Using Al2O3/TiO2 Dual-Layer Passivation Stack Prepared by Atomic Layer Deposition.

    PubMed

    Wang, Wei-Cheng; Tsai, Meng-Chen; Yang, Jason; Hsu, Chuck; Chen, Miin-Jang

    2015-05-20

    In this study, efficient nanotextured black silicon (NBSi) solar cells composed of silicon nanowire arrays and an Al2O3/TiO2 dual-layer passivation stack on the n(+) emitter were fabricated. The highly conformal Al2O3 and TiO2 surface passivation layers were deposited on the high-aspect-ratio surface of the NBSi wafers using atomic layer deposition. Instead of the single Al2O3 passivation layer with a negative oxide charge density, the Al2O3/TiO2 dual-layer passivation stack treated with forming gas annealing provides a high positive oxide charge density and a low interfacial state density, which are essential for the effective field-effect and chemical passivation of the n(+) emitter. In addition, the Al2O3/TiO2 dual-layer passivation stack suppresses the total reflectance over a broad range of wavelengths (400-1000 nm). Therefore, with the Al2O3/TiO2 dual-layer passivation stack, the short-circuit current density and efficiency of the NBSi solar cell were increased by 11% and 20%, respectively. In conclusion, a high efficiency of 18.5% was achieved with the NBSi solar cells by using the n(+)-emitter/p-base structure passivated with the Al2O3/TiO2 stack. PMID:25919200

  11. Williamson Home, Ipswich, Mass. solar-energy-system performance evaluation, Nov. 1981 - Apr. 1982

    NASA Astrophysics Data System (ADS)

    Cramer, M.

    1982-06-01

    Data on solar water and space heating systems are given. The Williamson Home in Massachusetts is a single family residence whose active-solar-energy system is designed to supply 47% of the space heating and 91% of the hot water. The system is equipped with 339 square feet of flat plate collectors, a 240-cubic-foot rock bin for storage, a propane-gas furnace and a 100-gallon propane gas hot water tank for auxiliary heating. Monthly performance data are tabulated for the overall system and for the collector, hot water, and space heating subsystems. Also tabulated are solar coefficients of performance, solar operating energy, energy savings, and weather conditions. Also given is a graph of collector array efficiency versus the difference between the inlet water and ambient temperatures divided by insolation. System operation is illustrated by graphs of typical insolation data and outside ambient and indoor temperatures, collector operating periods and inlet/outlet temperatures, and typical storage and distribution temperatures versus time for a typical day. The system operating sequence and solar energy utilization and losses are also graphed.

  12. Cultural Distance, Mindfulness and Passive Xenophobia: Using Integrated Threat Theory to Explore Home Higher Education Students' Perspectives on "Internationalisation at Home"

    ERIC Educational Resources Information Center

    Harrison, Neil; Peacock, Nicola

    2010-01-01

    This paper addresses the question of interaction between home and international students using qualitative data from 100 home students at two "teaching intensive" universities in the southwest of England. Stephan and Stephan's Integrated Threat Theory is used to analyse the data, finding evidence for all four types of threat that they predict when…

  13. SiC formation for a solar cell passivation layer using an RF magnetron co-sputtering system

    NASA Astrophysics Data System (ADS)

    Joung, Yeun-Ho; Kang, Hyun Il; Kim, Jung Hyun; Lee, Hae-Seok; Lee, Jaehyung; Choi, Won Seok

    2012-01-01

    In this paper, we describe a method of amorphous silicon carbide film formation for a solar cell passivation layer. The film was deposited on p-type silicon (100) and glass substrates by an RF magnetron co-sputtering system using a Si target and a C target at a room-temperature condition. Several different SiC [Si1-xCx] film compositions were achieved by controlling the Si target power with a fixed C target power at 150 W. Then, structural, optical, and electrical properties of the Si1-xCx films were studied. The structural properties were investigated by transmission electron microscopy and secondary ion mass spectrometry. The optical properties were achieved by UV-visible spectroscopy and ellipsometry. The performance of Si1-xCx passivation was explored by carrier lifetime measurement.

  14. SiC formation for a solar cell passivation layer using an RF magnetron co-sputtering system.

    PubMed

    Joung, Yeun-Ho; Kang, Hyun Il; Kim, Jung Hyun; Lee, Hae-Seok; Lee, Jaehyung; Choi, Won Seok

    2012-01-05

    In this paper, we describe a method of amorphous silicon carbide film formation for a solar cell passivation layer. The film was deposited on p-type silicon (100) and glass substrates by an RF magnetron co-sputtering system using a Si target and a C target at a room-temperature condition. Several different SiC [Si1-xCx] film compositions were achieved by controlling the Si target power with a fixed C target power at 150 W. Then, structural, optical, and electrical properties of the Si1-xCx films were studied. The structural properties were investigated by transmission electron microscopy and secondary ion mass spectrometry. The optical properties were achieved by UV-visible spectroscopy and ellipsometry. The performance of Si1-xCx passivation was explored by carrier lifetime measurement.

  15. A home-made system for IPCE measurement of standard and dye-sensitized solar cells

    SciTech Connect

    Palma, Giuseppina; Cozzarini, Luca; Capria, Ennio; Fraleoni-Morgera, Alessandro E-mail: afraleoni@units.it

    2015-01-15

    A home-made system for incident photon-to-electron conversion efficiency (IPCE) characterization, based on a double-beam UV-Vis spectrophotometer, has been set up. In addition to its low cost (compared to the commercially available apparatuses), the double-beam configuration gives the advantage to measure, autonomously and with no need for supplementary equipment, the lamp power in real time, compensating possible variations of the spectral emission intensity and quality, thus reducing measurement times. To manage the optical and electronic components of the system, a custom software has been developed. Validations carried out on a common silicon-based photodiode and on a dye-sensitized solar cell confirm the possibility to adopt this system for determining the IPCE of solar cells, including dye-sensitized ones.

  16. Karasek Home, Blackstone, Massachusetts solar-energy-system performance evaluation, Nov. 1981 - Mar. 1982

    NASA Astrophysics Data System (ADS)

    Raymond, M.

    1982-06-01

    The Karasek Home is a single family Massachusetts residence whose active-solar-energy system is equipped with 640 square feet of trickle-down liquid flat-plate collectors, storage in a 300-gallon tank and a 2000-gallon tank embedded in a rock bin in the basement, and an oil-fired glass-lined 40-gallon domestic hot water tank for auxiliary water and space heating. Monthly performance data are tabulated for the overall system and for the collector, storage, space heating, and domestic hot water subsystems. For each month a graph is presented of collector array efficiency versus the difference between the inlet water temperature and ambient temperature divided by insolation. Typical system operation is illustrated by graphs of insolation and temperatures at different parts of the system versus time for a typical day. The typical system operating sequence for a day is also graphed as well as solar energy utilization and heat losses.

  17. A home-made system for IPCE measurement of standard and dye-sensitized solar cells.

    PubMed

    Palma, Giuseppina; Cozzarini, Luca; Capria, Ennio; Fraleoni-Morgera, Alessandro

    2015-01-01

    A home-made system for incident photon-to-electron conversion efficiency (IPCE) characterization, based on a double-beam UV-Vis spectrophotometer, has been set up. In addition to its low cost (compared to the commercially available apparatuses), the double-beam configuration gives the advantage to measure, autonomously and with no need for supplementary equipment, the lamp power in real time, compensating possible variations of the spectral emission intensity and quality, thus reducing measurement times. To manage the optical and electronic components of the system, a custom software has been developed. Validations carried out on a common silicon-based photodiode and on a dye-sensitized solar cell confirm the possibility to adopt this system for determining the IPCE of solar cells, including dye-sensitized ones.

  18. Solar production of industrial process steam at the Home Cleaning and Laundry Co. Final technical report

    SciTech Connect

    Not Available

    1984-06-01

    This report presents the results of the operation and performance evaluation period at the Home Laundry Solar Industrial Process Heat Project at Pasadena, California. The installation comprises 6496 ft/sup 2/ (603.5 m/sup 2/) of linear parabolic trough concentrating collectors supplying solar thermal energy for use in laundry and dry cleaning processes. The design phase began in September 1977, and an acceptance test was conducted during the week of April 12, 1982. The plant has been in operation since May 1982, with the 12-month Phase III (operational) period starting in October 1982. The objective of the operational evaluation experiment was to maximize energy delivery to the industrial participant while characterizing system performance. Data were acquired for monthly documentation of system performance, maintenance requirements, and operating costs.

  19. Modeling the effects of indoor passive smoking at home, work, or other households on adult cardiovascular and mental health: the Scottish Health Survey, 2008-2011.

    PubMed

    Shiue, Ivy

    2014-03-01

    Passive smoking has contributed increased risks of cardiovascular disease, mental health, and mortality, but the cumulative effects from work or other households were less studied. Therefore, it was aimed to model the effects of indoor passive smoking from own home, work, and other households in a country-wide, population-based setting. Data in the Scottish Health Survey between 2008 and 2011 after the law banning smoking in public places were analyzed. Information including demographics, lifestyle factors, and self-reported cardiovascular disease and mental health was obtained by household interview. Analyses included chi-square test and survey-weighted logistic regression modeling. After full adjustment, it was observed that being exposed to indoor passive smoking, in particular in more than two places of exposure, was significantly associated with risks of stroke, angina, heart attack, abnormal heart rhythms, and GHQ ≥ 12. The significance remained for angina, GHQ ≥ 12 and probably heart attack in never smokers. The cumulative risks also impacted on sleep problems, self-recognition, making decisions, self-confidence, under strain constantly, depressed, happiness and self-worth. The significance remained for sleep problems, self-confidence, under strain constantly, depressed, and happiness in never smokers. Elimination of indoor passive smoking from different sources should still be a focus in future public health programs. PMID:24633145

  20. Modeling the Effects of Indoor Passive Smoking at Home, Work, or Other Households on Adult Cardiovascular and Mental Health: The Scottish Health Survey, 2008–2011

    PubMed Central

    Shiue, Ivy

    2014-01-01

    Passive smoking has contributed increased risks of cardiovascular disease, mental health, and mortality, but the cumulative effects from work or other households were less studied. Therefore, it was aimed to model the effects of indoor passive smoking from own home, work, and other households in a country-wide, population-based setting. Data in the Scottish Health Survey between 2008 and 2011 after the law banning smoking in public places were analyzed. Information including demographics, lifestyle factors, and self-reported cardiovascular disease and mental health was obtained by household interview. Analyses included chi-square test and survey-weighted logistic regression modeling. After full adjustment, it was observed that being exposed to indoor passive smoking, in particular in more than two places of exposure, was significantly associated with risks of stroke, angina, heart attack, abnormal heart rhythms, and GHQ ≥ 12. The significance remained for angina, GHQ ≥ 12 and probably heart attack in never smokers. The cumulative risks also impacted on sleep problems, self-recognition, making decisions, self-confidence, under strain constantly, depressed, happiness and self-worth. The significance remained for sleep problems, self-confidence, under strain constantly, depressed, and happiness in never smokers. Elimination of indoor passive smoking from different sources should still be a focus in future public health programs. PMID:24633145

  1. Solar Schematic

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The home shown at right is specially designed to accommodate solar heating units; it has roof planes in four directions, allowing placement of solar collectors for best exposure to the sun. Plans (bottom) and complete working blueprints for the solar-heated house are being marketed by Home Building Plan Service, Portland, Oregon. The company also offers an inexpensive schematic (center) showing how a homeowner only moderately skilled in the use of tools can build his own solar energy system, applicable to new or existing structures. The schematic is based upon the design of a low-cost solar home heating system built and tested by NASA's Langley Research Center; used to supplement a warm-air heating system, it can save the homeowner about 40 percent of his annual heating bill for a modest investment in materials and components. Home Building Plan Service saved considerable research time by obtaining a NASA technical report which details the Langley work. The resulting schematic includes construction plans and simplified explanations of solar heat collection, collectors and other components, passive heat factors, domestic hot water supply and how to work with local heating engineers.

  2. Passive solar energy effects on egg production and feed efficiency phase II

    SciTech Connect

    MacDougall, E.A.

    1981-01-01

    The production efficiency of a small solar heated hen house are compared to those of a large commercial operation. The solar hen house proved to give higher egg production than the larger commercial operation. Feed efficiencies for the commercial operation are better than the solar hen house in reporting grain used per dozen eggs. 6 refs.

  3. A study to determine the perceptions of Michigan contractors to passive solar technologies in residential and commercial construction

    SciTech Connect

    Witte, P.

    1983-06-01

    This study was intended to investigate the perceptions and needs of Michigan contractors in incorporating passive solar technologies in residential and commercial construction. The literature identifies four major categories of barriers which contribute to the slow adoption of solar systems by contractors. They are: economic (initial high price, interest rates, etc.), technological (perceived lack of reliable equipment, lack of elimatelogical data, etc.), psycho-sociological (dependence on the weather, threat to established business networks, etc.) and political-legal (product standardization, building and zoning codes, etc.). A questionnaire aimed at detecting the importance of the four barrier categories was administered to a random sample of 500 Michigan contractors. This paper outlines the procedure utilized in conducting the study. A review of the questionnaire's development and administration is given, followed by a presentation of preliminary data on the completed questionnaires received to date (n = 75).

  4. High-efficiency screen-printed silicon ribbon solar cells by effective defect passivation and rapid thermal processing

    NASA Astrophysics Data System (ADS)

    Rohatgi, Ajeet; Jeong, Ji-Weon

    2003-01-01

    A conversion efficiency of 15.9% has been achieved on low-cost edge-defined film-fed grown silicon ribbon solar cells. This represents an improvement over the previously reported efficiencies for silicon ribbon solar cells with manufacturable screen-printed contacts and single layer silicon nitride (SiNx) antireflection coating. Two separate rapid thermal processing cycles with fast ramp-up and cooling rates contributed to the enhancement in cell efficiency. The fast ramp-up rate improved the quality of back surface field and contacts; and a short firing time with a fast cooling rate improved contacts and the SiNx-induced hydrogen passivation of defects, resulting in bulk lifetime enhancement from ˜2 to ˜50 μs.

  5. Energy Performance Analysis of Ultra-Efficient Homes at Solar Decathlon 2013

    NASA Astrophysics Data System (ADS)

    Garkhail, Rahul

    The objective of this thesis is to investigate the various types of energy end-uses to be expected in future high efficiency single family residences. For this purpose, this study has analyzed monitored data from 14 houses in the 2013 Solar Decathlon competition, and segregates the energy consumption patterns in various residential end-uses (such as lights, refrigerators, washing machines, ...). The analysis was not straight-forward since these homes were operated according to schedules previously determined by the contest rules. The analysis approach allowed the isolation of the comfort energy use by the Heating, Venting and Cooling (HVAC) systems. HVAC are the biggest contributors to energy consumption during operation of a building, and therefore are a prime concern for energy performance during the building design and the operation. Both steady state and dynamic models of comfort energy use which take into account variations in indoor and outdoor temperatures, solar radiation and thermal mass of the building were explicitly considered. Steady State Inverse Models are frequently used for thermal analysis to evaluate HVAC energy performance. These are fast, accurate, offer great flexibility for mathematical modifications and can be applied to a variety of buildings. The results are presented as a horizontal study that compares energy consumption across homes to arrive at a generic rather than unique model - to be used in future discussions in the context of ultra efficient homes. It is suggested that similar analyses of the energy-use data that compare the performance of variety of ultra efficient technologies be conducted to provide more accurate indications of the consumption by end use for future single family residences. These can be used alongside the Residential Energy Consumption Survey (RECS) and the Leading Indicator for Remodeling Activity (LIRA) indices to assist in planning and policy making related to residential energy sector.

  6. Improvement of the SiOx passivation layer for high-efficiency Si/PEDOT:PSS heterojunction solar cells.

    PubMed

    Sheng, Jiang; Fan, Ke; Wang, Dan; Han, Can; Fang, Junfeng; Gao, Pingqi; Ye, Jichun

    2014-09-24

    Interfacial properties currently hinder the performance of Si/organic heterojunction solar cells for an alternative to high-efficiency and low-cost photovoltaics. Here, we present a simple and repeatable wet oxidation method for developing the surface passivation layer, SiOx, on the Si surface for the fabrication of high-efficiency Si/poly(3,4-ethylene-dioxythiophene):polystyrenesulfonate (PEDOT:PSS) heterojunction solar cells. The uniform and dense SiOx thin layer introduced by the oxidizing aqueous solution of H2O2 or HNO3 provided the better surface passivation and stronger wettability of the Si surface, compared to those in the native oxide case. These two types of progress helped create a lower defect density at the Si/PEDOT:PSS interface and thus a high-quality p-n junction with a lower interface recombination velocity. As a result, the HNO3-oxidized device displayed better performance with a power conversion efficiency (PCE) of 11%, representing a 28.96% enhancement from the PCE of 8.53% in the native oxide case. The effects on the performance of the Si/PEDOT:PSS hybrid solar cells of the wet oxidation treatment procedure, including the differences in surface roughness and wettability of the Si substrate, the quality and thickness of the SiOx, etc., were explored extensively. Such a simple and controllable oxidizing treatment could be an effective way to promote the interfacial properties that are an important cornerstone for more efficient Si/organic hybrid solar cells.

  7. Study of surface passivation as a function of InP closed-ampoule solar cell fabrication processing variables

    NASA Technical Reports Server (NTRS)

    Faur, Mircea; Faur, Maria; Jenkins, Phillip; Goradia, Manju; Goradia, Chandra; Bailey, Sheila; Weinberg, Irving; Jayne, Douglas

    1990-01-01

    The effects of various surface preparation procedures, including chemical treatment and anodic or chemical oxidation, closed-ampoule diffusion conditions, and post-diffusion surface preparation and annealing conditions, on the passivating properties of InP have been investigated in order to optimize the fabrication procedures of n(+)p InP solar cells made by closed-ampoule diffusion of sulfur into p-type InP. The InP substrates used were p-type Cd-doped to a level of 1.7 x 10 to the 16th/cu cm, Zn-doped to levels of 2.2 x 10 to the 16th and 1.2 x 10 to the 18th/cu cm, and n-type S-doped to 4.4 x 10 to the 18th/cu cm. The passivating properties have been evaluated from photoluminescence (PL) and conductance-voltage (G-V) data. Good agreement was found between the level of surface passivation and the composition of different surface layers as revealed by X-ray photoelectron spectroscopy (XPS) analysis.

  8. Passivating boron silicate glasses for co-diffused high-efficiency n-type silicon solar cell application

    SciTech Connect

    Engelhardt, Josh Frey, Alexander; Gloger, Sebastian; Hahn, Giso; Terheiden, Barbara

    2015-07-27

    Doping layers commonly have but one function: supplying the dopants to form a doped region within a substrate. This work presents B doping layers/stacks, which at the same time supply dopant atoms, passivate the B-doped crystalline Si surface sufficiently well (j{sub 0E} < 50 fA/cm{sup 2}), and show optical properties suitable for anti-reflective coating. Furthermore, these boron silicate glasses can act as a barrier against parasitic P in-diffusion during a co-diffusion step. The boron emitters diffused from the inductively coupled plasma plasma-enhanced chemical vapor-deposited B containing SiO{sub x} layers are investigated and optimized concerning passivation quality and contact properties for high-efficiency n-type solar Si cell designs. It is shown that even 10 nm thin SiO{sub x}:B films already allow for suitable emitter sheet resistance for screen-printed contacts. Furthermore, SiO{sub x}:B layers presented here allow for iV{sub OC} values of 675 mV and contact resistivity of 1 mΩcm{sup 2} for commercial Ag instead of Ag/Al pastes on the diffused boron emitter passivated with the SiO{sub x}:B layer supporting the contact formation. All of these properties can be achieved within one single B doping layer/stack.

  9. Carrier Selective, Passivated Contacts for High Efficiency Silicon Solar Cells based on Transparent Conducting Oxides

    DOE PAGES

    Young, David L.; Nemeth, William; Grover, Sachit; Norman, Andrew; Yuan, Hao-Chih; Lee, Benjamin G.; LaSalvia, Vincenzo; Stradins, Paul

    2014-01-01

    We describe the design, fabrication and results of passivated contacts to n-type silicon utilizing thin SiO2 and transparent conducting oxide layers. High temperature silicon dioxide is grown on both surfaces of an n-type wafer to a thickness <50 Å, followed by deposition of tin-doped indium oxide (ITO) and a patterned metal contacting layer. As deposited, the thin-film stack has a very high J0,contact, and a non-ohmic, high contact resistance. However, after a forming gas anneal, the passivation quality and the contact resistivity improve significantly. The contacts are characterized by measuring the recombination parameter of the contact (J0,contact) and the specificmore » contact resistivity (ρcontact) using a TLM pattern. The best ITO/SiO2 passivated contact in this study has J0,contact = 92.5 fA/cm2 and ρcontact = 11.5 mOhm-cm2. These values are placed in context with other passivating contacts using an analysis that determines the ultimate efficiency and the optimal area fraction for contacts for a given set of (J0,contact, ρcontact) values. The ITO/SiO2 contacts are found to have a higher J0,contact, but a similar ρcontact compared to the best reported passivated contacts.« less

  10. Long-term measurement of indoor thermal environment and energy performance in a detached wooden house with passive solar systems

    SciTech Connect

    Ishikawa, Yoshimi; Yoshino, Hiroshi; Sasaki, Chikashi

    1998-07-01

    The indoor thermal environment, energy performance and energy consumption for a detached wooden house equipped with two passive solar systems, were investigated over a period of three years. The house with a floor area of 188 m{sup 2} was constructed in the autumn of 1993 in Sendai, Japan; and was well insulated and very airtight compared with other houses in Japan. There are six occupants. Heating equipment is comprises of a thermal storage space heater using night-time electricity and a vented firewood furnace on the first floor. Each room is ventilated all day by a central ventilation system. Two passive solar systems were incorporated: a concrete floor in the southern perimeter of the living room as a direct gain system, and an earth tube embedded around the circumference of the house to supply fresh air. The principal results obtained are as follows: (1) The indoor environment during the heating season was more thermally comfortable, compared with that or ordinary houses in Japan. (2) The concrete floor played a role of thermal storage, which absorbed and released heat for decreasing the fluctuation of room temperature. (3) The earth tube supplied air with lower temperature in the summer and higher temperature in the winter to the room, that the outdoor air temperature. This thermal performance did not decrease in spite of the long-term use. (4) The annual amount of energy consumption of this house was less than that of ordinary houses in the northern part of Japan.

  11. Module greenhouse with high efficiency of transformation of solar energy, utilizing active and passive glass optical rasters

    SciTech Connect

    Korecko, J.; Jirka, V.; Sourek, B.; Cerveny, J.

    2010-10-15

    Since the eighties of the 20th century, various types of linear glass rasters for architectural usage have been developed in the Czech Republic made by the continuous melting technology. The development was focused on two main groups of rasters - active rasters with linear Fresnel lenses in fixed installation and with movable photo-thermal and/or photo-thermal/photo-voltaic absorbers. The second group are passive rasters based on total reflection of rays on an optical prism. During the last years we have been working on their standardization, exact measuring of their optical and thermal-technical characteristics and on creation of a final product that could be applied in solar architecture. With the project supported by the Ministry of Environment of the Czech Republic we were able to build an experimental greenhouse using these active and passive optical glass rasters. The project followed the growing number of technical objectives. The concept of the greenhouse consisted of interdependence construction - structural design of the greenhouse with its technological equipment securing the required temperature and humidity conditions in the interior of the greenhouse. This article aims to show the merits of the proposed scheme and presents the results of the mathematical model in the TRNSYS environment through which we could predict the future energy balance carried out similar works, thus optimizing the investment and operating costs. In this article description of various technology applications for passive and active utilization of solar radiation is presented, as well as some results of short-term and long-term experiments, including evaluation of 1-year operation of the greenhouse from the energy and interior temperature viewpoints. A comparison of the calculated energy flows in the greenhouse to real measured values, for verification of the installed model is also involved. (author)

  12. Kalin Home, Long Island, New York: Solar-energy-system performance evaluation, Sep. 1981-Mar. 1982

    NASA Astrophysics Data System (ADS)

    Howard, B. D.

    Performance data on a solar water heating system are given. The Kalin Home is a single family residence in East Meadow, Long Island, New York whose active solar energy system is designed to supply 60% of the hot water load. The system is equipped with 2 flat plate collectors with a combined area of 48 square feet and a 120-gallon tank for storage. Auxiliary heating is provided by a 4.5 kW single-element electric heater interfaced to off-peak power metering equipment to deliver auxiliary energy from midnight through 7:00 AM. Performance data for the total reporting period are summarized. In addition, monthly performance data are tabulated for the overall system and or the collector and domestic hot water subsystems. Predicted performance and performance measured during previous systems are also given for comparison. System operation for a typical day is illustrated by graphs of temperatures at various points in the system vs. time and by hourly water consumption graphs. A typical system operating sequence and solar energy utilization and heat losses are also graphed.

  13. Tierra concrete homes: Low-energy residential building design

    SciTech Connect

    Hayter, S.J.; Torcellini, P.A.; Neimeyer, J.

    1997-12-31

    Using a whole building design concept, Tierra Concrete Homes, a home builder in Pueblo, Colorado, created low-energy, passive solar home designs. Passive solar features incorporated into the designs include house orientation, high-mass walls for thermal storage, exterior insulation, appropriate glazing type combined with overhangs to prevent summer overheating, open interior spaces to maximize daylighting potential, and high efficiency lighting. These ranch-style homes require no cooling and minimum heating equipment to maintain comfortable indoor conditions. They are economically competitive to build, consume little fossil fuel, and produce virtually no construction waste. This paper discusses how the design of one of these homes was optimized to further minimize energy consumption while maintaining an attractive livable environment. It also describes monitoring activities that are currently underway to verify predicted energy consumption.

  14. Excellent Passivation and Low Reflectivity Al2O3/TiO2 Bilayer Coatings for n-Wafer Silicon Solar Cells: Preprint

    SciTech Connect

    Lee, B. G.; Skarp, J.; Malinen, V.; Li, S.; Choi, S.; Branz, H. M.

    2012-06-01

    A bilayer coating of Al2O3 and TiO2 is used to simultaneously achieve excellent passivation and low reflectivity on p-type silicon. This coating is targeted for achieving high efficiency n-wafer Si solar cells, where both passivation and anti-reflection (AR) are needed at the front-side p-type emitter. It could also be valuable for front-side passivation and AR of rear-emitter and interdigitated back contact p-wafer cells. We achieve high minority carrier lifetimes {approx}1 ms, as well as a nearly 2% decrease in absolute reflectivity, as compared to a standard silicon nitride AR coating.

  15. Preliminary model for heat transport within a tongue-and-reservoir liquid diode for passive solar heating

    SciTech Connect

    Jones, G.F.

    1984-01-01

    A preliminary model is presented for heat transport within a tongue-and-reservoir liquid diode for passive solar heating. The diode consists of a rectangular vertical slot (tongue) extending from the bottom of a rectangular-shaped reservoir at the reservoir's front face. Water is used as the working fluid in the tongue and reservoir. Solar radiation is incident on the front face of the tongue, which also loses heat to the outside, while radiation and convection transport heat from the back of the reservoir to the building. Convection transports heat when the tongue is irradiated; however, when convection ceases and the temperature of the tongue cools below that of the reservoir (from exposure to the outside temperature), the reservoir stratifies, and the primary heat loss mechanism is conduction through the tongue and its fluid. The result is a passive solar component that may outperform most others. Flow in the tongue is treated as boundary layer flow; the integral forms of the governing equations are combined to form a single equation governing the local boundary layer thickness. The results are shown to depend upon the Grashof, Prandtl, and heat-loss Biot numbers. Results from this model agree well with those from our flow visualization experiments. A model is also proposed for diode heat transport processes during cool-down. In this model, and empirical coefficient accounts for the weak convective mixing that occurs in the reservoir during this phase. Preliminary results indicate the coefficient to be spatially dependent but independent of time and reservoir temperature. More experiments are planned to further validate both of the models described above.

  16. Carrier Selective, Passivated Contacts for High Efficiency Silicon Solar Cells based on Transparent Conducting Oxides

    SciTech Connect

    Young, David L.; Nemeth, William; Grover, Sachit; Norman, Andrew; Yuan, Hao-Chih; Lee, Benjamin G.; LaSalvia, Vincenzo; Stradins, Paul

    2014-01-01

    We describe the design, fabrication and results of passivated contacts to n-type silicon utilizing thin SiO2 and transparent conducting oxide layers. High temperature silicon dioxide is grown on both surfaces of an n-type wafer to a thickness <50 Å, followed by deposition of tin-doped indium oxide (ITO) and a patterned metal contacting layer. As deposited, the thin-film stack has a very high J0,contact, and a non-ohmic, high contact resistance. However, after a forming gas anneal, the passivation quality and the contact resistivity improve significantly. The contacts are characterized by measuring the recombination parameter of the contact (J0,contact) and the specific contact resistivity (ρcontact) using a TLM pattern. The best ITO/SiO2 passivated contact in this study has J0,contact = 92.5 fA/cm2 and ρcontact = 11.5 mOhm-cm2. These values are placed in context with other passivating contacts using an analysis that determines the ultimate efficiency and the optimal area fraction for contacts for a given set of (J0,contact, ρcontact) values. The ITO/SiO2 contacts are found to have a higher J0,contact, but a similar ρcontact compared to the best reported passivated contacts.

  17. Enhanced photovoltaic performance of inverted pyramid-based nanostructured black-silicon solar cells passivated by an atomic-layer-deposited Al2O3 layer.

    PubMed

    Chen, Hong-Yan; Lu, Hong-Liang; Ren, Qing-Hua; Zhang, Yuan; Yang, Xiao-Feng; Ding, Shi-Jin; Zhang, David Wei

    2015-10-01

    Inverted pyramid-based nanostructured black-silicon (BS) solar cells with an Al2O3 passivation layer grown by atomic layer deposition (ALD) have been demonstrated. A multi-scale textured BS surface combining silicon nanowires (SiNWs) and inverted pyramids was obtained for the first time by lithography and metal catalyzed wet etching. The reflectance of the as-prepared BS surface was about 2% lower than that of the more commonly reported upright pyramid-based SiNW BS surface over the whole of the visible light spectrum, which led to a 1.7 mA cm(-2) increase in short circuit current density. Moreover, the as-prepared solar cells were further passivated by an ALD-Al2O3 layer. The effect of annealing temperature on the photovoltaic performance of the solar cells was investigated. It was found that the values of all solar cell parameters including short circuit current, open circuit voltage, and fill factor exhibit a further increase under an optimized annealing temperature. Minority carrier lifetime measurements indicate that the enhanced cell performance is due to the improved passivation quality of the Al2O3 layer after thermal annealing treatments. By combining these two refinements, the optimized SiNW BS solar cells achieved a maximum conversion efficiency enhancement of 7.6% compared to the cells with an upright pyramid-based SiNWs surface and conventional SiNx passivation.

  18. System manual for the University of Pennsylvania retrofitted solar heated Philadelphia row home (SolaRow)

    SciTech Connect

    Zinnes, I.; Lior, N.

    1980-05-01

    The University of Pennsylvania SolaRow house, an urban row home retrofitted for comfort and domestic hot water heating, was extensively instrumented for performance monitoring and acquisition of weather and solar radiation data. This report describes the heating and instrumentation systems, provides the details for instrumentation, piping and valve identification, and specifies the operation and maintenance of the heating and data acquisition systems. The following are included: (1) system flow diagrams; (2) valve and cable identification tables; (3) wiring diagrams; and (4) start-up, normal operation, shut-down, maintenance and trouble-shooting procedures. It thus provides the necessary technical information to permit system operation and monitoring, overall system performance analysis and optimization, and acquisition of climatological data.

  19. Establish feasibility for providing passive cooling with solar updraft and evaporate downdraft chimneys

    SciTech Connect

    Cunningham, W.A.; Mignon, G.V.; Thompson, T.L.

    1987-01-01

    Natural draft towers can be used for cooling and ventilating structures. From an operational perspective, the downdraft evaporatively cooled tower is preferred for a dry climate. Solar chimneys, when used alone, tend to require an excessively large solar collector area when appreciable quantities of air must be moved. When used in combination with a downdraft tower, the roof and attic of buildings may assist the solar chimney and their use becomes more attractive. Both a frame building and a greenhouse were successfully cooled during this program. The economics of the downdraft tower compare favorably with conventional evaporative cooling for some applications.

  20. Establish feasibility for providing passive cooling with solar updraft and evaporative downdraft chimneys

    SciTech Connect

    Cunningham, W.A.; Mignon, G.V.; Thompson, T.L.

    1987-01-01

    Natural draft towers can be used for cooling and ventilating structures. From an operational perspective, the downdraft evaporatively cooled tower is preferred for a dry climate. Solar chimneys, when used alone, tend to require an excessively large solar collector area when appreciable quantities of air must be moved. When used in combination with a downdraft tower, the roof and attic of buildings may assist the solar chimney and their use becomes more attractive. Both a frame building and a greenhouse were successfully cooled during this program. The economics of the downdraft tower compare favorably with conventional evaporative cooling for some application.

  1. An overview of the first results on the solar array passive LDEF experiment (sample), AO171

    NASA Technical Reports Server (NTRS)

    Whitaker, Ann F.; Young, Leighton E.

    1991-01-01

    Space environmental effects were visibly obvious on components of experiment AO171 which contained solar cells, composites, polymeric thin films, solar reflectors, protective coatings, metals, paints , and elastomers. Micrometeoroid/space debris impacts were observed on all experiment elements. Luminescence of polyimide, silicone, and polyurethane materials occurred under black light examination. Outgassing of RTV511 occurred mainly as a result of insufficient thermal vacuum bakeout. Solar cell degradation was predominantly below 10 percent. Elastomers lost mass and discolored; composites showed evidence of atomic oxygen attack, and unprotected thin polymer films eroded away.

  2. Hydrogen passivation of n+p and p+n heteroepitaxial InP solar cell structures

    NASA Technical Reports Server (NTRS)

    Chatterjee, B.; Ringel, S. A.; Hoffman, R., Jr.

    1995-01-01

    High-efficiency, heteroepitaxial (HE) InP solar cells, grown on GaAs, Si or Ge substrates, are desirable for their mechanically strong, light-weight and radiation-hard properties. However, dislocations, caused by lattice mismatch, currently limit the performance of the HE cells. This occurs through shunting paths across the active photovoltaic junction and by the formation of deep levels. In previous work we have demonstrated that plasma hydrogenation is an effective and stable means to passivate the electrical activity of dislocations in specially designed HE InP test structures. In this work, we present the first report of successful hydrogen passivation in actual InP cell structures grown on GaAs substrates by metalorganic chemical vapor deposition (MOCVD). We have found that a 2 hour exposure to a 13.56 MHz hydrogen plasma at 275 C reduces the deep level concentration in HE n+n InP cell structures from as-grown values of approximately 10(exp 15)/cm(exp -3), down to 1-2 x 10(exp 13)/cm(exp -3). The deep levels in the p-type base region of the cell structure match those of our earlier p-type test structures, which were attributed to dislocations or related point defect complexes. All dopants were successfully reactivated by a 400 C, 5 minute anneal with no detectable activation of deep levels. I-V analysis indicated a subsequent approximately 10 fold decrease in reverse leakage current at -1 volt reverse bias, and no change in the forward biased series resistance of the cell structure which indicates complete reactivation of the n+ emitter. Furthermore, electrochemical C-V profiling indicates greatly enhanced passivation depth, and hence hydrogen diffusion, for heteroepitaxial structures when compared with identically processed homoepitaxial n+p InP structures. An analysis of hydrogen diffusion in dislocated InP will be discussed, along with comparisons of passivation effectiveness for n+p versus p+n heteroepitaxial cell configurations. Preliminary hydrogen-passivated

  3. Metal insulator semiconductor solar cell devices based on a Cu{sub 2}O substrate utilizing h-BN as an insulating and passivating layer

    SciTech Connect

    Ergen, Onur; Gibb, Ashley; Vazquez-Mena, Oscar; Zettl, Alex; Regan, William Raymond

    2015-03-09

    We demonstrate cuprous oxide (Cu{sub 2}O) based metal insulator semiconductor Schottky (MIS-Schottky) solar cells with efficiency exceeding 3%. A unique direct growth technique is employed in the fabrication, and hexagonal boron nitride (h-BN) serves simultaneously as a passivation and insulation layer on the active Cu{sub 2}O layer. The devices are the most efficient of any Cu{sub 2}O based MIS-Schottky solar cells reported to date.

  4. Metal insulator semiconductor solar cell devices based on a Cu2O substrate utilizing h-BN as an insulating and passivating layer

    NASA Astrophysics Data System (ADS)

    Ergen, Onur; Gibb, Ashley; Vazquez-Mena, Oscar; Regan, William Raymond; Zettl, Alex

    2015-03-01

    We demonstrate cuprous oxide (Cu2O) based metal insulator semiconductor Schottky (MIS-Schottky) solar cells with efficiency exceeding 3%. A unique direct growth technique is employed in the fabrication, and hexagonal boron nitride (h-BN) serves simultaneously as a passivation and insulation layer on the active Cu2O layer. The devices are the most efficient of any Cu2O based MIS-Schottky solar cells reported to date.

  5. Design and application of ion-implanted polySi passivating contacts for interdigitated back contact c-Si solar cells

    NASA Astrophysics Data System (ADS)

    Yang, Guangtao; Ingenito, Andrea; van Hameren, Nienke; Isabella, Olindo; Zeman, Miro

    2016-01-01

    Ion-implanted passivating contacts based on poly-crystalline silicon (polySi) are enabled by tunneling oxide, optimized, and used to fabricate interdigitated back contact (IBC) solar cells. Both n-type (phosphorous doped) and p-type (boron doped) passivating contacts are fabricated by ion-implantation of intrinsic polySi layers deposited via low-pressure chemical vapor deposition and subsequently annealed. The impact of doping profile on the passivation quality of the polySi doped contacts is studied for both polarities. It was found that an excellent surface passivation could be obtained by confining as much as possible the implanted-and-activated dopants within the polySi layers. The doping profile in the polySi was controlled by modifying the polySi thickness, the energy and dose of ion-implantation, and the temperature and time of annealing. An implied open-circuit voltage of 721 mV for n-type and 692 mV for p-type passivating contacts was achieved. Besides the high passivating quality, the developed passivating contacts exhibit reasonable high conductivity (Rsh n-type = 95 Ω/□ and Rsh p-type = 120 Ω/□). An efficiency of 19.2% (Voc = 673 mV, Jsc = 38.0 mA/cm2, FF = 75.2%, and pseudo-FF = 83.2%) was achieved on a front-textured IBC solar cell with polySi passivating contacts as both back surface field and emitter. By improving the front-side passivation, a VOC of 696 mV was also measured.

  6. DOE Zero Energy Ready Home Case Study, Weiss Building & Development, LLC., System Home, River Forest, Illinois

    SciTech Connect

    none,

    2013-09-01

    The Passive House Challenge Home located in River Forest, Illinois, is a 5-bedroom, 4.5-bath, 3,600 ft2 two-story home (plus basement) that costs about $237 less per month to operate than a similar sized home built to the 2009 IECC. For a home with no solar photovoltaic panels installed, it scored an amazingly low 27 on the Home Energy Rating System (HERS) score.An ENERGY STAR-rated dishwasher, clothes washer, and refrigerator; an induction cooktop, condensing clothes dryer, and LED lighting are among the energy-saving devices inside the home. All plumbing fixtures comply with EPA WaterSense criteria. The home was awarded a 2013 Housing Innovation Award in the "systems builder" category.

  7. Enhanced Organic Solar Cell Stability through the Effective Blocking of Oxygen Diffusion using a Self-Passivating Metal Electrode.

    PubMed

    Lee, Hansol; Jo, Sae Byeok; Lee, Hyo Chan; Kim, Min; Sin, Dong Hun; Ko, Hyomin; Cho, Kilwon

    2016-03-01

    A new and simple strategy for enhancing the stability of organic solar cells (OSCs) was developed by using self-passivating metal top electrodes. Systematic investigations on O2 permeability of Al top electrodes revealed that the main pathways for oxidation-induced degradation could be greatly suppressed by simply controlling the nanoscale morphology of the Al electrode. The population of nanoscale pinholes among Al grains, which critically decided the diffusion of O2 molecules toward the Al-organic interfaces that are vulnerable to oxidation, was successfully regulated by rapidly depositing Al or promoting lateral growth among the Al grains, accompanied by increasing the deposition thickness. Our observations suggested that the stability of OSCs with conventional architectures might be greatly enhanced simply by controlling the fabrication conditions of the Al top electrode, without the aid of additional secondary treatments.

  8. Effective passivation of the low resistivity silicon surface by a rapid thermal oxide/PECVD silicon nitride stack and its application to passivated rear and bifacial Si solar cells

    SciTech Connect

    Rohatgi, A.; Narasimha, S.; Ruby, D.S.

    1998-08-01

    A novel stack passivation scheme, in which plasma silicon nitride (SiN) is stacked on top of a rapid thermal SiO{sub 2} (RTO) layer, is developed to attain a surface recombination velocity (S) approaching 10 cm/s at the 1.3 {Omega}-cm p-type (100) silicon surface. Such low S is achieved by the stack even when the RTO and SiN films individually yield considerably poorer surface passivation. Critical to achieving low S by the stack is the use of a short, moderate temperature anneal (in this study 730 C for 30 seconds) after film growth and deposition. This anneal is believed to enhance the release and delivery of atomic hydrogen from the SiN film to the Si-SiO{sub 2} interface, thereby reducing the density of interface traps at the surface. Compatibility with this post-deposition anneal makes the stack passivation scheme attractive for cost-effective solar cell production since a similar anneal is required to fire screen-printed contacts. Application of the stack to passivated rear screen-printed solar cells has resulted in V{sub oc}`s of 641 mV and 633 mV on 0.65 {Omega}-cm and 1.3 {Omega}-cm FZ Si substrates, respectively. These V{sub oc} values are roughly 20 mV higher than for cells with untreated, highly recombinative back surfaces. The stack passivation has also been used to form fully screen-printed bifacial solar cells which exhibit rear-illuminated efficiency as high as 11.6% with a single layer AR coating.

  9. Passive solar commercial buildings: design assistance and demonstration program. Phase 1. Final report

    SciTech Connect

    1981-01-26

    The final design of the Mount Airy Public Library is given. Incremental passive design costs are discussed. Performance and economic analyses are made and the results reported. The design process is thoroughly documented. Considerations discussed are: (1) building energy needs; (2) site energy potentials, (3) matching energy needs with site energy potentials, (4) design indicators for best strategies and concepts, (5) schematic design alternatives, (6) performance testing of the alternatives, (7) design selection, and (8) design development. Weather data and Duke Power electric rates are included. (LEW)

  10. Performance of an active/passive hybrid solar system utilizing vapor transport

    SciTech Connect

    Hedstrom, J.C.

    1984-01-01

    Vapor-phase heat-transport systems are being tested in two of the passive test cells at Los Alamos. The systems consist of an active fin-and-tube collector and a condenser inside a water storage tank. The refrigerant, R-11, can be returned to the collector with a pump or with a self-pumping scheme. A computer model was developed to predict the behavior of the system, after which the computer was used to predict the annual performance of these systems in five cities. The report compares the measured and the predicted results as well as the system's sensitivity to several parameters.

  11. Low-cost foil metallization using arc discharge for passivated emitter and rear solar cells

    NASA Astrophysics Data System (ADS)

    Kurimoto, Yuji; Yamasaki, Ichiro

    2016-04-01

    For the cost reduction of passivated emitter and rear cells (PERC), we propose a new rear contact formation method, in which an aluminum foil and an arc discharge system are used. The arc discharge system consists of inexpensive parts and does not contain any sophisticated part such as a laser ablation apparatus. Therefore, this system can save the cost of the rear contact forming process. We applied this technique to a test production of PERC. It is found that the arc discharge system can provide a similar performance to that attained by a conventional PERC production method.

  12. Sunspace Minnesota: passive solar design for winter resorts. Period covered, August 1979-October 1980

    SciTech Connect

    Johnson, J.M.

    1980-01-01

    Minnesota winter resorts are discussed as to type, size, and use. Energy needs and conservation techniques are described by cabin type and problem areas. Existing cabins are analyzed for conservation opportunities and solar retrofit potential. New cabin designs and concepts are presented including earth sheltered buildings. (MHR)

  13. Carrier collection losses in interface passivated amorphous silicon thin-film solar cells

    NASA Astrophysics Data System (ADS)

    Neumüller, A.; Bereznev, S.; Ewert, M.; Volobujeva, O.; Sergeev, O.; Falta, J.; Vehse, M.; Agert, C.

    2016-07-01

    In silicon thin-film solar cells the interface between the i- and p-layer is the most critical. In the case of back diffusion of photogenerated minority carriers to the i/p-interface, recombination occurs mainly on the defect states at the interface. To suppress this effect and to reduce recombination losses, hydrogen plasma treatment (HPT) is usually applied. As an alternative to using state of the art HPT we apply an argon plasma treatment (APT) before the p-layer deposition in n-i-p solar cells. To study the effect of APT, several investigations were applied to compare the results with HPT and no plasma treatment at the interface. Carrier collection losses in resulting solar cells were examined with spectral response measurements with and without bias voltage. To investigate single layers, surface photovoltage and X-ray photoelectron spectroscopy (XPS) measurements were conducted. The results with APT at the i/p-interface show a beneficial contribution to the carrier collection compared with HPT and no plasma treatment. Therefore, it can be concluded that APT reduces the recombination centers at the interface. Further, we demonstrate that carrier collection losses of thin-film solar cells are significantly lower with APT.

  14. Passivation properties of aluminum oxide films deposited by mist chemical vapor deposition for solar cell applications

    NASA Astrophysics Data System (ADS)

    Miki, Shohei; Iguchi, Koji; Kitano, Sho; Hayakashi, Koki; Hotta, Yasushi; Yoshida, Haruhiko; Ogura, Atsushi; Satoh, Shin-ichi; Arafune, Koji

    2015-08-01

    Aluminum oxide (AlOx) films were deposited by mist chemical vapor deposition (MCVD) in air for p-type crystalline silicon, and the effects of the deposition temperature (Tdep) and AlOx film thickness on the maximum surface recombination velocities (Smax) were evaluated. It was found that Smax was improved with increasing Tdep. The AlOx film deposited at 400 °C exhibited the best Smax value of 2.8 cm/s, and the passivation quality was comparable to that of AlOx deposited by other vacuum-based techniques. Smax was also improved with increasing film thickness. When the film thickness was above 10 nm, Smax was approximately 10 cm/s. From the Fourier transform infrared spectra, it was found that the AlOx films deposited by MCVD consisted of an AlOx layer and a Si-diffused AlOx layer. In addition, it is important for the layers to be thick enough to obtain high-quality passivation.

  15. Well-Passivated a-Si:H Back Contacts for Double-Heterojunction Silicon Solar Cells: Preprint

    SciTech Connect

    Page, M. R.; Iwaniczko, E.; Xu, Y.; Wang, Q.; Yan, Y.; Roybal, L.; Branz, H. M.; Wang, T. H.

    2006-05-01

    We have developed hydrogenated amorphous silicon (a Si:H) back contacts to both p- and n-type silicon wafers, and employed them in double-heterojunction solar cells. These contacts are deposited entirely at low temperature (<250 C) and replace the standard diffused or alloyed back-surface-field contacts used in single-heterojunction (front-emitter only) cells. High-quality back contacts require excellent surface passivation, indicated by a low surface recombination velocity of minority-carriers (S) or a high open-circuit voltage (Voc). The back contact must also provide good conduction for majority carriers to the external circuit, as indicated by a high light I-V fill factor. We use hot-wire chemical vapor deposition (HWCVD) to grow a-Si:H layers for both the front emitters and back contacts. Our improved a-Si:H back contacts contribute to our recent achievement of a confirmed 18.2% efficiency in double-heterojunction silicon solar cells on p type textured silicon wafers.

  16. Inorganic compounds for passive solar energy storage: Solid-state dehydration materials and high specific heat materials

    NASA Astrophysics Data System (ADS)

    Struble, L. J.; Brown, P. W.

    1986-04-01

    Two classes of hydrated inorganic salts have been studied to assess their potential as materials for passive solar energy storage. The materials are part of the quaternary system CaO-Al2O3-SO3-H2O and related chemical systems, and the two classes are typified by ettringite, a trisubstituted salt, and Friedel's salt, a monosubstituted salt. The trisubstituted salts were studied for their possible application in latent heat storage, utilizing a low-temperature dehydration reaction, and both classes were studies for their application in sensible heat storage. In order to assess their potential for energy storage, the salts have been synthesized, characterized by several analytical techniques, and thermal properties measured. The dehydration data of that the trisubstituted salts vary somewhat with chemical composition, with the temperature of the onset of dehydration ranging from 6(0)C to 33(0)C, and enthalpy changes on dehydration ranging from 60 to 200 cal/g. Heat capacity is less variable with composition; values for the trisubstituted phases are 30 cal/g/(0)C and for the monosubstituted phases between 0.23 and 0.28 cal/g/(0)C. Preliminary experiments indicate that the dehydration is reversible, and suggest that the materials might have additional potential as solar desiccant materials. These thermal data demonstrate the trisubstituted salts have potential as latent heat storage materials, and that both classes of salts have potential as sensible heat storage materials.

  17. Low temperature surface passivation of crystalline silicon and its application to interdigitated back contact silicon heterojunction (ibc-shj) solar cell

    NASA Astrophysics Data System (ADS)

    Shu, Zhan

    With the absence of shading loss together with improved quality of surface passivation introduced by low temperature processed amorphous silicon crystalline silicon (a-Si:H/c-Si) heterojunction, the interdigitated back contact silicon heterojunction (IBC-SHJ) solar cell exhibits a potential for higher conversion efficiency and lower cost than a traditional front contact diffused junction solar cell. In such solar cells, the front surface passivation is of great importance to achieve both high open-circuit voltage (Voc) and short-circuit current (Jsc). Therefore, the motivation of this work is to develop a low temperature processed structure for the front surface passivation of IBC-SHJ solar cells, which must have an excellent and stable passivation quality as well as a good anti-reflection property. Four different thin film materials/structures were studied and evaluated for this purpose, namely: amorphous silicon nitride (a-SiNx:H), thick amorphous silicon film (a-Si:H), amorphous silicon/silicon nitride/silicon carbide (a-Si:H/a-SiN x:H/a-SiC:H) stack structure with an ultra-thin a-Si:H layer, and zinc sulfide (ZnS). It was demonstrated that the a-Si:H/a-SiNx:H/a-SiC:H stack surpasses other candidates due to both of its excellent surface passivation quality (SRV<5 cm/s) and lower absorption losses. The low recombination rate at the stack structure passivated c-Si surface is found to be resulted from (i) field effect passivation due to the positive fixed charge (Q fix~1x1011 cm-2 with 5 nm a-Si:H layer) in a-SiNx:H as measured from capacitance-voltage technique, and (ii) reduced defect state density (mid-gap Dit~4x1010 cm-2eV-1) at a-Si:H/c-Si interface provided by a 5 nm thick a-Si:H layer, as characterized by conductance-frequency measurements. Paralleled with the experimental studies, a computer program was developed in this work based on the extended Shockley-Read-Hall (SRH) model of surface recombination. With the help of this program, the experimental

  18. Origin and elimination of photocurrent hysteresis by fullerene passivation in CH3NH3PbI3 planar heterojunction solar cells

    DOE PAGES

    Shao, Yuchuan; Xiao, Zhengguo; Bi, Cheng; Yuan, Yongbo; Huang, Jinsong

    2014-12-15

    The large photocurrent hysteresis observed in many organometal trihalide perovskite solar cells has become a major hindrance impairing the ultimate performance and stability of these devices, while its origin was unknown. Here we demonstrate the trap states on the surface and grain boundaries of the perovskite materials to be the origin of photocurrent hysteresis and that the fullerene layers deposited on perovskites can effectively passivate these charge trap states and eliminate the notorious photocurrent hysteresis. Fullerenes deposited on the top of the perovskites reduce the trap density by two orders of magnitude and double the power conversion efficiency of CH3NH3PbI3more » solar cells. As a result, the elucidation of the origin of photocurrent hysteresis and its elimination by trap passivation in perovskite solar cells provides important directions for future enhancements to device efficiency.« less

  19. Performance Results from a Cold Climate Case Study for Affordable Zero Energy Homes: Preprint

    SciTech Connect

    Norton, P.; Christensen, C.

    2007-11-01

    The design of this 1280 square foot, 3-bedroom Denver zero energy home carefully combines envelope efficiency, efficient equipment, appliances and lighting, a photovoltaic system, and passive and active solar thermal features to exceed the net zero energy goal. In January 2006, a data acquisition system was installed in the home to monitor its performance over the course of a year. This paper presents full year of energy performance data on the home.

  20. Surface recombination velocity of phosphorus-diffused silicon solar cell emitters passivated with plasma enhanced chemical vapor deposited silicon nitride and thermal silicon oxide

    NASA Astrophysics Data System (ADS)

    Kerr, M. J.; Schmidt, J.; Cuevas, A.; Bultman, J. H.

    2001-04-01

    The emitter saturation current density (JOe) and surface recombination velocity (Sp) of various high quality passivation schemes on phosphorus-diffused solar cell emitters have been determined and compared. The passivation schemes investigated were (i) stoichiometric plasma enhanced chemical vapor deposited (PECVD) silicon nitride (SiN), (ii) forming gas annealed thermally grown silicon oxide, and (iii) aluminum annealed (alnealed) thermal silicon oxide. Emitters with sheet resistances ranging from 30 to 430 and 50 to 380 Ω/□ were investigated for planar and random-pyramid textured silicon surfaces, which covers both industrial and laboratory emitters. The electronic surface passivation quality provided by PECVD SiN films was found to be good, with Sp values ranging from 1400 to 25 000 cm/s for planar emitters. Thin thermal silicon oxides were found to provide superior passivation to PECVD SiN, with the best passivation provided by an alnealed thin oxide (Sp values between 250 and 21 000 cm/s). The optimized PECVD SiN films are, nevertheless, sufficiently good for most silicon solar cell applications.

  1. Implementation of Tunneling Passivated Contacts into Industrially Relevant n-Cz Si Solar Cells

    SciTech Connect

    Nemeth, William; LaSalvia, Vincenzo; Page, Matthew R.; Warren, Emily L.; Dameron, Arrelaine; Norman, Andrew G.; Lee, Benjamin G.; Young, David L.; Stradins, Paul

    2015-06-14

    We identify bottlenecks, and propose solutions, to implement a B-diffused front emitter and a backside pc-Si/SiO2 pasivated tunneling contact into high efficiency n-Cz Si cells in an industrially relevant way. We apply an O-precipitate dissolution treatment to make n-Cz wafers immune to bulk lifetime process degradation, enabling robust, passivated B front emitters with J0 <; 20fA/cm2. Adding ultralow recombination n+ pc-Si/SiO2 back contacts enables pre-metallized cells with iVoc=720 mV and J0=8.6 fA/cm2. However, metallization significantly degrades performance of these contacts due to pinholes and possibly, grain boundary diffusion of primary metal and source contaminates such as Cu. An intermediate, doped a-Si:H capping layer is found to significantly block the harmful metal penetration into pc-Si.

  2. Passive and hybrid solar manufactured housing and buildings. Phase 1: Technical proposal

    NASA Astrophysics Data System (ADS)

    Osika, K. F.

    1981-08-01

    The design objective for manufacturing farrowing-nursery building for hog confinement which uses a minimal amount of winter heat and is relatively cool in summer is discussed. Savings are to be accomplished by using an air to air heat exchanger, a hot air collector, and a wood stove in place of backup bottle gas. Solar alternatives and design criteria are described. A thermal analysis was performed.

  3. Program to monitor and evaluate a passive solar greenhouse/aquaculture system. Final report

    SciTech Connect

    Not Available

    1982-01-01

    A temperature monitoring program of Amity's solar greenhouse demonstrated that air, soil, and water temperatures can be maintained at optimal levels without supplemental heat. A foil reflector placed in front of the greenhouse glazing at an angle of between 0 and 5/sup 0/ above horizontal enhanced direct light entering the greenhouse by as much as 22%. Aquaculture in the water heat storage of a solar greenhouse has been a success. Fish reached harvest size in about seven months. The two species that were received the best by the public were African perch (Tilapia mossambica) and channel catfish (Ictalurus punctatus). Although carp (Cyprinus carpio) were the fastest growers they were not well received by the public. Linking hydroponics to greenhouse aquaculture shows a lot of promise. Different support medias were examined and tomatoes and European cucumbers were raised successfully. A savonius windmill was successfully linked to an aquaculture aeration system but because of the wind pattern in the Willamette valley the windmill system did not provide air in the evening when it was needed most. Alternate designs are discussed. Locally grown fish diets were evaluated for their ability to promote fish growth. Diets such as water hyacinth, duckweed, earthworms, beans, and comfrey were raised on the Amity site, pelleted with a hand grinder and solar dried. Duckweed and earthworms appear to hold promise for a nutritous, easy to grow and pelletize, food source. Amity's solar greenhouse, three coldframe designs and a PVC tunnel cloche were compared in a vegetable growing trial. Most impressive was the cloche design because it provided adequate protection, was inexpensive and very easy to build.

  4. Passive and hybrid solar manufactured housing and buildings. Final report, Phase I. Technical proposal

    SciTech Connect

    Osika, K.F.

    1981-08-01

    The design objective is to manufacture a farrowing-nursery building for hog confinement which uses a minimal amount of winter heat and is relatively cool in summer. Savings are accomplished by using an air to air heat exchanger, a hot air collector, and a wood stove in place of backup bottle gas. Solar alternatives and design criteria are described. A thermal analysis is performed. Included is a description of W.H. Porter, Inc. (LEW)

  5. Thermal control system and method for a passive solar storage wall

    DOEpatents

    Ortega, Joseph K. E.

    1984-01-01

    The invention provides a system and method for controlling the storing and elease of thermal energy from a thermal storage wall wherein said wall is capable of storing thermal energy from insolation of solar radiation. The system and method includes a device such as a plurality of louvers spaced a predetermined distance from the thermal wall for regulating the release of thermal energy from the thermal wall. This regulating device is made from a material which is substantially transparent to the incoming solar radiation so that when it is in any operative position, the thermal storage wall substantially receives all of the impacting solar radiation. The material in the regulating device is further capable of being substantially opaque to thermal energy so that when the device is substantially closed, thermal release of energy from the storage wall is substantially minimized. An adjustment device is interconnected with the regulating mechanism for selectively opening and closing it in order to regulate the release of thermal energy from the wall.

  6. Impact of interstitial oxygen trapped in silicon during plasma growth of silicon oxy-nitride films for silicon solar cell passivation

    NASA Astrophysics Data System (ADS)

    Saseendran, Sandeep S.; Saravanan, S.; Raval, Mehul C.; Kottantharayil, Anil

    2016-03-01

    Low temperature oxidation of silicon in plasma ambient is a potential candidate for replacing thermally grown SiO2 films for surface passivation of crystalline silicon solar cells. In this work, we report the growth of silicon oxy-nitride (SiOxNy) film in N2O plasma ambient at 380 °C. However, this process results in trapping of interstitial oxygen within silicon. The impact of this trapped interstitial oxygen on the surface passivation quality is investigated. The interstitial oxygen trapped in silicon was seen to decrease for larger SiOxNy film thickness. Effective minority carrier lifetime (τeff) measurements on n-type float zone silicon wafers passivated by SiOxNy/silicon nitride (SiNv:H) stack showed a decrease in τeff from 347 μs to 68 μs, for larger SiOxNy film thickness due to degradation in interface properties. From high frequency capacitance-voltage measurements, it was concluded that the surface passivation quality was governed by the interface parameters (fixed charge density and interface state density). High temperature firing of the SiOxNy/SiNv:H stack resulted in a severe degradation in τeff due to migration of oxygen across the interface into silicon. However, on using the SiOxNy/SiNv:H stack for emitter surface passivation in screen printed p-type Si solar cells, an improvement in short wavelength response was observed in comparison to the passivation by SiNv:H alone, indicating an improvement in emitter surface passivation quality.

  7. Enhanced performance of polymer solar cell with ZnO nanoparticle electron transporting layer passivated by in situ cross-linked three-dimensional polymer network

    NASA Astrophysics Data System (ADS)

    Wu, Zhongwei; Song, Tao; Xia, Zhouhui; Wei, Huaixin; Sun, Baoquan

    2013-12-01

    An in situ cross-linked three-dimensional polymer network has been developed to passivate ZnO nanoparticles as an electron transporting layer (ETL) to improve the performance of inverted organic solar cells. The passivated ZnO ETL-based devices achieve efficiencies of 3.26% for poly(3-hexylthiophene) (P3HT):[6,6]-phenyl-C61-butyric acid methyl ester (PCBM) and 7.37% for poly[[4,8-bis[(2-ethylhexyl)oxy]benzo[1,2-b:4,5-b‧]dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl

  8. Proof-of-Concept Testing of the Passive Cooling System (T-CLIP™) for Solar Thermal Applications at an Elevated Temperature

    SciTech Connect

    Kim, Seung Jun; Quintana, Donald L.; Vigil, Gabrielle M.; Perraglio, Martin Juan; Farley, Cory Wayne; Tafoya, Jose I.; Martinez, Adam L.

    2015-11-30

    The Applied Engineering and Technology-1 group (AET-1) at Los Alamos National Laboratory (LANL) conducted the proof-of-concept tests of SolarSPOT LLC’s solar thermal Temperature- Clipper, or T-CLIP™ under controlled thermal conditions using a thermal conditioning unit (TCU) and a custom made environmental chamber. The passive T-CLIP™ is a plumbing apparatus that attaches to a solar thermal collector to limit working fluid temperature and to prevent overheating, since overheating may lead to various accident scenarios. The goal of the current research was to evaluate the ability of the T-CLIP™ to control the working fluid temperature by using its passive cooling mechanism (i.e. thermosiphon, or natural circulation) in a small-scale solar thermal system. The assembled environmental chamber that is thermally controlled with the TCU allows one to simulate the various possible weather conditions, which the solar system will encounter. The performance of the T-CLIP™ was tested at two different target temperatures: 1) room temperature (70 °F) and 2) an elevated temperature (130 °F). The current test campaign demonstrated that the T-CLIP™ was able to prevent overheating by thermosiphon induced cooling in a small-scale solar thermal system. This is an important safety feature in situations where the pump is turned off due to malfunction or power outages.

  9. Site handbook: data acquisition system information, passive solar retrofit Automobile Maintenance Facility, City of Philadelphia

    SciTech Connect

    Not Available

    1985-01-01

    Data were collected at the City of Philadelphia's Auto Maintenance Facility using an Aeoloan Kinetics PDL-24 data acquisition system. Instantaneous data readings were recorded each 15 seconds by the microprocessor. These channel readings were then averaged to produce hourly values which were then stored on an audio cassette. The energy saving strategies include: styrofoam and concrete roof coverings; weatherstripping; replacement of north windows with combination insulation and view glazing; PVC strips between heated and unheated areas; gas fired radiant heaters at individual work stations; reduction of the number of light fixtures; and the installation of retrofit window units for radiant solar heating, daylighting, ventilation, glare control and vandalism protection.

  10. Powering a Home with Just 25 Watts of Solar PV. Super-Efficient Appliances Can Enable Expanded Off-Grid Energy Service Using Small Solar Power Systems

    SciTech Connect

    Phadke, Amol A.; Jacobson, Arne; Park, Won Young; Lee, Ga Rick; Alstone, Peter; Khare, Amit

    2015-04-01

    Highly efficient direct current (DC) appliances have the potential to dramatically increase the affordability of off-grid solar power systems used for rural electrification in developing countries by reducing the size of the systems required. For example, the combined power requirement of a highly efficient color TV, four DC light emitting diode (LED) lamps, a mobile phone charger, and a radio is approximately 18 watts and can be supported by a small solar power system (at 27 watts peak, Wp). Price declines and efficiency advances in LED technology are already enabling rapidly increased use of small off-grid lighting systems in Africa and Asia. Similar progress is also possible for larger household-scale solar home systems that power appliances such as lights, TVs, fans, radios, and mobile phones. When super-efficient appliances are used, the total cost of solar home systems and their associated appliances can be reduced by as much as 50%. The results vary according to the appliances used with the system. These findings have critical relevance for efforts to provide modern energy services to the 1.2 billion people worldwide without access to the electrical grid and one billion more with unreliable access. However, policy and market support are needed to realize rapid adoption of super-efficient appliances.

  11. Effect of passivation layer grown by atomic layer deposition and sputtering processes on Si quantum dot superlattice to generate high photocurrent for high-efficiency solar cells

    NASA Astrophysics Data System (ADS)

    Maksudur Rahman, Mohammad; Higo, Akio; Sekhar, Halubai; Erman Syazwan, Mohd; Hoshi, Yusuke; Usami, Noritaka; Samukawa, Seiji

    2016-03-01

    The effect of passivation films on a Si quantum dot superlattice (QDSL) was investigated to generate high photocurrent in solar-cell applications. Three types of passivation films, sputter-grown amorphous silicon carbide (a-SiC), hydrogenated a-SiC (a-SiC:H), and atomic-layer-deposited aluminum oxide (ALD-Al2O3), were used to passivate the Si QDSLs containing a stack of four 4 nm Si nanodisks (NDs) and 2 nm silicon carbide (SiC) films fabricated by neutral beam etching (NBE). Because of the high surface-to-volume ratio typically present in quantum Si-NDs formed in the top-down NBE process, there is a tendency to form larger surface dangling bonds on untreated Si-ND surfaces as well as to have short distance (<10 nm) between high-aspect-ratio nanopillars of stacked 4 nm Si-NDs/2 nm SiC films, which conventionally sputter SiC films cannot uniformly cover. Therefore, we optimized the passivation techniques with an ALD-Al2O3 film. Scanning electron microscopy (SEM) analysis helped to explain the surface morphology before and after the passivation of the QDSLs. After the completion of the passivation process, the quality of the top surface films of the QDSLs was analyzed from the surface roughness by atomic force microscopy (AFM) analysis, which revealed that ALD-Al2O3 passivated films had the smallest roughness (RMS) of 1.09 nm with respect to sputter-grown a-SiC (RMS: 1.75 nm) and a-SiC:H (RMS: 1.54 nm) films. Conductive atomic force microscopy (CAFM) revealed that ALD-Al2O3 passivation decreased the surface-leakage current as a result of proper passivation of side-wall surface defects in the QDSLs. The carrier transport characteristics were extracted from the QDSLs using the photovoltaic (PV) properties of p++/i/n+ solar cells, where the QDSLs consisted of different passivation layers acting as intermediate layers (i-layers) between the high-doping-density p++ Si (1 × 1020 cm-3) and n+ Si (1 × 1019 cm-3) substrates. High-doping-density p++ Si acted as a hole

  12. MIS Solar Cell Devices Based on a Cu2 O Substrate Utilizing h-BN as an Insulating and Passivating Layer

    NASA Astrophysics Data System (ADS)

    Ergen, Onur; Gibb, Ashley; Vazquez-Mena, Oscar; Regan, Will; Zettl, Alex

    2015-03-01

    We demonstrate Cu2O based metal insulator semiconductor Schottky (MIS-Schottky) solar cells with efficiency exceeding 3%. A unique direct growth technique is employed in the fabrication, and hexagonal boron nitride (h-BN) serves simultaneously as a passivation and insulation layer on the active cuprous oxide (Cu2O) layer. The devices are the most efficient of any Cu2O based MIS-Schottky solar cells reported to date. Department of Physics, University of California at Berkeley, Berkeley, California 94720, USA. Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA. Kavli Energy Nanosciences Institute at the University of Berkeley, CA, USA.

  13. Hood River Passive House

    SciTech Connect

    Hales, D.

    2013-03-01

    The Hood River Passive Project was developed by Root Design Build of Hood River Oregon using the Passive House Planning Package (PHPP) to meet all of the requirements for certification under the European Passive House standards. The Passive House design approach has been gaining momentum among residential designers for custom homes and BEopt modeling indicates that these designs may actually exceed the goal of the U.S. Department of Energy's (DOE) Building America program to reduce home energy use by 30%-50% (compared to 2009 energy codes for new homes). This report documents the short term test results of the Shift House and compares the results of PHPP and BEopt modeling of the project.

  14. Passive solar heating and natural cooling of an earth-integrated design

    SciTech Connect

    Barnes, P. R.; Shapira, H. B.

    1980-01-01

    The Joint Institute for Heavy Ion Research is being designed with innovative features that will greatly reduce its energy consumption for heating, cooling, and lighting. A reference design has been studied and the effects of extending the overhang during summer and fall, varying glazing area, employing RIB, and reducing internal heat by natural lighting have been considered. The use of RIB and the extendable overhang increases the optimum window glazing area and the solar heating fraction. A mass-storage wall which will likely be included in the final design has also been considered. A figure of merit for commercial buildings is the total annual energy consumption per unit area of floor space. A highly efficient office building in the Oak Ridge area typically uses 120 to 160 kWhr/m/sup 2/. The Joint Institute reference design with natural lighting, an annual average heat pump coefficient of performance (COP) equal to 1.8, RIB, and the extendable overhang uses 71 kWhr/m/sup 2/. This figure was determined from NBSLD simulations corrected for the saving from RIB. The internal heat energy from lighting and equipment used in the simulation was 1653 kWhrs/month (high natural lighting case) which is much lower than conventional office buildings. This value was adopted because only a portion of the building will be used as office space and efforts will be made to keep internal heat generation low. The mass-storage wall and ambient air cooling will reduce energy consumption still further. The combined savings of the innovative features in the Joint Institute building are expected to result in a very energy efficient design. The building will be instrumented to monitor its performance and the measured data will provide a means of evaluating the energy-saving features. The efficiency of the design will be experimentally verified over the next several years.

  15. Development of an advanced solar augmented water heater (for single family home applications)

    NASA Astrophysics Data System (ADS)

    Grunes, H.; Morrison, D.; Dewinter, F.

    1982-06-01

    A program was undertaken to design, construct and test two advanced prototype solar augmented gas water heaters. Computer analyses and experimental work were used to optimize components and characterize performance. The resulting design includes a solar preheat tank, a gas-fired backup tank, the collector loop pump and all operating controls contained in a single cylindrical package. The backup tank is positioned above the solar preheat tank. The connection between the solar and backup tanks is effectively a thermal diode which restricts heat transfer from the backup to the solar tank but allows the backup tank to become an integral part of solar storage whenever the solar tank temperature surpasses the backup tank set point temperature. Solar heat is supplied through a jacketed tank drainback system.

  16. Solar project description: First manufactured homes (lot 219) single family residence, Lubbock, Texas

    NASA Astrophysics Data System (ADS)

    Moore, D.

    1981-08-01

    A system designed to provide solar space heating and to preheat domestic hot water is described. The collector, storage, energy to load, and auxiliary subsystems are described. Operation of the solar and auxiliary systems may involve one or more of five modes of operations: collector to storage, direct solar to space heating, storage to space heating, preheating domestic hot water, and auxiliary space heating. Original cost estimates for provisioning and installation of the solar system are given.

  17. DOE Zero Energy Ready Home Case Study: Amaris Custom Homes, St. Paul, Minnesota

    SciTech Connect

    2015-06-01

    For this project, Amaris worked with U.S. Department of Energy (DOE) team, NorthernSTAR Building America Partnership, to develop the first Zero Energy Ready Home (ZERH) in Minnesota's cold climate using reasonable, cost-effective, and replicable construction materials and practices. The result is a passive solar, super-efficient 3542-ft2 walkout ranch-style home with all the creature comforts. Along with meeting ZERH standards, Amaris also achieved certifications for Leadership in Energy & Environmental Design for Homes v4, MN Green Path Emerald, and a Builders Association of the Twin Cities Reggie Award of Excellence. The home achieves a HERS score of 41 without photovoltaics; with PV, the home achieves a HERS score of 5.

  18. The Impact of Neighbourhood Density on the Energy Demand of Passive Houses and on Potential Energy Sources from the Waste Flows and Solar Energy

    NASA Astrophysics Data System (ADS)

    Stupka, Robert

    This study demonstrates how the density of a neighbourhood affects its energy demand, metabolism (energy and material flows) and its ability to produce its own energy. Single-family detached houses and row townhouses were each modeled using passive solar housing guidelines with the DesignBuilder building energy simulation software. Energy demand is then modeled within neighbourhoods at two densities based on south facing windows fully un-shaded at 9:00 am, and 12:00 pm solar time on Dec. 21. The neighbourhood metabolisms were then calculated based on location and density. The potential energy supply was evaluated from the spatial characteristics of the neighbourhood (for solar) and the metabolism (municipal solid waste and wastewater flows.) The potential energy demand and supply are then compared for the varying building types and densities to determine the sensitivity of the energy supply and demand relationships.

  19. DOE Zero Energy Ready Home Case Study: TC Legend Homes — Cedarwood, Bellingham, WA

    SciTech Connect

    none,

    2014-09-01

    This house was the Grand Winner in the Affordable Builder category of the 2014 Housing Innovation Awards, and has 6-inch SIP walls, a 10-inch structural insulated panel roof, and insulating concrete forms foundation walls with R-20 high-density rigid EPS foam under the slab.A single ductless heat pump heats and cools the home, which also gets passive solar heating from south-facing triple-pane windows that heat a concrete slab floor plus a connected greenhouse.

  20. Rear-Sided Passivation by SiNx:H Dielectric Layer for Improved Si/PEDOT:PSS Hybrid Heterojunction Solar Cells

    NASA Astrophysics Data System (ADS)

    Sun, Yiling; Gao, Pingqi; He, Jian; Zhou, Suqiong; Ying, Zhiqin; Yang, Xi; Xiang, Yong; Ye, Jichun

    2016-06-01

    Silicon/organic hybrid solar cells have recently attracted great attention because they combine the advantages of silicon (Si) and the organic cells. In this study, we added a patterned passivation layer of silicon nitride (SiNx:H) onto the rear surface of the Si substrate in a Si/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) hybrid solar cell, enabling an improvement of 0.6 % in the power conversion efficiency (PCE). The addition of the SiNx:H layer boosted the open circuit voltage ( V oc) from 0.523 to 0.557 V, suggesting the well-passivation property of the patterned SiNx:H thin layer that was created by plasma-enhanced chemical vapor deposition and lithography processes. The passivation properties that stemmed from front PEDOT:PSS, rear-SiNx:H, front PEDOT:PSS/rear-SiNx:H, etc. are thoroughly investigated, in consideration of the process-related variations.

  1. ENU mutagenesis screening for dominant behavioral mutations based on normal control data obtained in home-cage activity, open-field, and passive avoidance tests.

    PubMed

    Wada, Yumiko; Furuse, Tamio; Yamada, Ikuko; Masuya, Hiroshi; Kushida, Tomoko; Shibukawa, Yoko; Nakai, Yuji; Kobayashi, Kimio; Kaneda, Hideki; Gondo, Yoichi; Noda, Tetsuo; Shiroishi, Toshihiko; Wakana, Shigeharu

    2010-01-01

    To establish the cutoff values for screening ENU-induced behavioral mutations, normal variations in mouse behavioral data were examined in home-cage activity (HA), open-field (OF), and passive-avoidance (PA) tests. We defined the normal range as one that included more than 95% of the normal control values. The cutoffs were defined to identify outliers yielding values that deviated from the normal by less than 5% for C57BL/6J, DBA/2J, DBF(1), and N(2) (DXDB) progenies. Cutoff values for G1-phenodeviant (DBF(1)) identification were defined based on values over +/- 3.0 SD from the mean of DBF(1) for all parameters assessed in the HA and OF tests. For the PA test, the cutoff values were defined based on whether the mice met the learning criterion during the 2nd (at a shock intensity of 0.3 mA) or the 3rd (at a shock intensity of 0.15 mA) retention test. For several parameters, the lower outliers were undetectable as the calculated cutoffs were negative values. Based on the cutoff criteria, we identified 275 behavioral phenodeviants among 2,646 G1 progeny. Of these, 64 were crossed with wild-type DBA/2J individuals, and the phenotype transmission was examined in the G2 progeny using the cutoffs defined for N(2) mice. In the G2 mice, we identified 15 novel dominant mutants exhibiting behavioral abnormalities, including hyperactivity in the HA or OF tests, hypoactivity in the OF test, and PA deficits. Genetic and detailed behavioral analysis of these ENU-induced mutants will provide novel insights into the molecular mechanisms underlying behavior.

  2. Home-made experiment of Dye-sensitized TiO2 Nanocrystalline Solar Cells and its education evaluation

    NASA Astrophysics Data System (ADS)

    Tai, M. F.; Shieh, M. C.; Chen, T. W.

    2010-03-01

    Dyes extracted from some natural fruits including anthocyanins absorb sunlight and effectively activate electrons of anthocyanins. Thus these activated electrons are conducted between TiO2 nanocrystals and form electric potential and current between two electrodes. The dyes can be gotten from the natural fruits, such as blackberries, raspberry, pomegranate seeds and bing cherries. This principle permits making a dye sensitized TiO2 nanocrystallines solar cell (DSSC). All required materials and tools for fabricating a home- made DSSC are easy to obtain around home. The procedures are perfect hands-on experiment as well as demonstration in K-12 schools or home settings. We have designed several protocols for fabricating DSSC and have successfully demonstrated in more than 100 activities with different level students. K-12 Students were able to build their own working DSSC's within 2-3 hours sessions and learned about alternative energy sources. These experiments can inspire students and general public about the modern technology in daily life. Low cost (low than US 3 in Taiwan)and safety are also ensured in our DSSC experiments.

  3. Clean energy choices: Tips on buying and using renewable energy at home

    SciTech Connect

    NREL

    2000-04-07

    This brochure provides information on how consumers can use renewable energy in and around the home. Information on buying green power; using renewables to generate power; using passive and active solar and geothermal heat pumps to heat, cool and light buildings; and using alternative fuels and vehicles is included. Resources at the end of each chapter help readers find more information.

  4. Willow Park II Community Center. Overview of the design report for the passive solar commercial buildings design assistance and demonstration program

    SciTech Connect

    Freeman, Thomas E.

    1981-01-15

    The final design of the 4130 sq ft community center is briefly reviewed. Incremental passive design costs are broken down and tabulated. Energy consumption by various components is computed by the ENERGYLOOK computer program, and the final design's energy use is computed with the DOE-2,0A program. Results of these computations are shown graphically. Life-cycle values are computed using the VISICALC program, and the economic analysis results are tabulated. Design drawings are included. Incremental solar construction cost estimates are tabulated. (LEW)

  5. Marketing the solar suburb and beyond

    SciTech Connect

    Miller, C.

    1999-07-01

    New England Solar Homes is an emerging solar home company offering custom architectural services as well as a line of standard house plans to clients across the country. Their standard builder's sets can be used off the shelf or altered to fit varied climates and siting conditions. The Solar Farmhouse concept house was introduced at the Eco-Expo in 1995 as a demonstration of how an American country classic could be adapted and outfitted to be an advanced energy efficient passive and active solar home that would have immediate popular appeal. The inspiration for this design was based on the wisdom and surprisingly skillful design abilities of the American farmer, circa 1800s and onward. The Solonial became the first built demonstration home in Lexington, MA incorporating the energy performance standards of the Solar Farmhouse. Two other homes will start construction this spring--Solar Farmhouse II, and DC Solar I, in Pennsylvania and Maryland, respectively. The Beyond in the title refers to their interest in participating in the New Urbanism movement which is gaining momentum around the country in equal proportion to the loss of habitat from urban sprawl with its impact on quality of life indicators. Solar designers and developers could find some emerging opportunities with this highly unusual American attempt at regional planning.

  6. Research and demonstration facilities for energy conservation and solar heating in the home

    NASA Astrophysics Data System (ADS)

    Newman, J. O.; Godbey, L. C.; Davis, M. A.; Ezell, D. O.; Allen, W. H.

    1981-10-01

    The design, testing and evaluation of two prototype solar holes are discussed. The first prototype is a greenhouse-residence designed with 6-in. wall cavities (to increase insulation thickness), a 381 sq. ft. solar collector used primarily for space heating, and a greenhouse that was utilized as a solar collector for growing vegetables. The house does feature a domestic hot water preheating system and an electrical resistance back-up heating system. The second prototype is an earth-insulated house designed primarily to study the physical features of the house in relation to the soil around it and the thermal interaction between the soil and the house environment. This house features a high temperature air collector that is used for domestic water heating. A special effort was made to have adequate daylight in the solar-earth house. A special study was conducted on the geometric configuration of the rock storage and the methods of admitting air to the rock storage.

  7. Hood River Passive House, Hood River, Oregon (Fact Sheet)

    SciTech Connect

    Not Available

    2014-02-01

    The Hood River Passive Project was developed by Root Design Build of Hood River Oregon using the Passive House Planning Package (PHPP) to meet all of the requirements for certification under the European Passive House standards. The Passive House design approach has been gaining momentum among residential designers for custom homes and BEopt modeling indicates that these designs may actually exceed the goal of the U.S. Department of Energy's (DOE) Building America program to "reduce home energy use by 30%-50%" (compared to 2009 energy codes for new homes). This report documents the short term test results of the Shift House and compares the results of PHPP and BEopt modeling of the project. The design includes high R-Value assemblies, extremely tight construction, high performance doors and windows, solar thermal DHW, heat recovery ventilation, moveable external shutters and a high performance ductless mini-split heat pump. Cost analysis indicates that many of the measures implemented in this project did not meet the BA standard for cost neutrality. The ductless mini-split heat pump, lighting and advanced air leakage control were the most cost effective measures. The future challenge will be to value engineer the performance levels indicated here in modeling using production based practices at a significantly lower cost.

  8. Leak path passivation by in situ Al-N for InGaN solar cells operating at wavelengths up to 570 nm

    NASA Astrophysics Data System (ADS)

    Wang, Ke; Imai, Daichi; Kusakabe, Kazuhide; Yoshikawa, Akihiko

    2016-02-01

    A leak path passivation (LPP) technology for InGaN solar cells with photo-response up to 570 nm was developed by inserting in situ monolayers of Al-N into active layers. The InGaN layer in the passivated sample is partially relaxed and incorporates more than 23.5% In. By adopting in situ Al-N LPP, the open circuit voltage increases from 0.96 V to 1.35 V under one sun illumination (1.45-1.68 V under 72 suns), and the dark shunt resistance increases from 3.6 kΩ cm2 to 12.6 kΩ cm2, leading to an increase in power conversion efficiency by a factor of 2.0-2.26 (1-72 suns). This in situ Al-N LPP approach paves a way to exploit the full potential of InGaN for high efficiency solar cell application, accepting the reality of defective high-In-content thick and relaxed InGaN.

  9. Summary of the Northstar home: An extension of the Solar 80 Program

    NASA Astrophysics Data System (ADS)

    1981-09-01

    The objective of the Northstar program was to develop and evaluate a detailed design for a low cost house suited for cold climates which would be acceptable to mid-income families and would not need a furnace. The program's four phases are described, including a demonstration design, demonstration construction and monitoring, development of a family of alternative designs, and commercialization. A brief description of the home is included.

  10. The Fuel Savers: A Kit of Solar Ideas for Existing Homes.

    ERIC Educational Resources Information Center

    Scully, Dan; And Others

    This publication is a collection of solar heating ideas for the do-it-yourselfer. The ideas are presented in a clear, simple and sometimes amusing way. Although written for homeowners, these ideas may be used in businesses and schools as well. Some ideas may make good student projects. The suggestions are illustrated and their costs and probable…

  11. Evaluation of determination methods of the Si/Al contact resistance of screen-printed passivated emitter and rear solar cells

    NASA Astrophysics Data System (ADS)

    Müller, M.; Lottspeich, F.

    2014-02-01

    The Si/Al contact resistance of narrow p-type contact areas of crystalline silicon solar cells is a crucial parameter for the further development and improvement of passivated emitter and rear (PERC) solar cells. In this paper, two methods for determining the rear contact resistance are analyzed and improved: the series resistance analysis and the transfer length method (TLM). We use an experimental set of PERC solar cells with varying metallization fraction, and we analyze the experiment using numerical device simulation. In the first method, the resistive losses are extracted from the I-V-curves of the PERC cells, and the rear contact resistance is separated by subtracting the analytically calculated base contribution. The state-of-the-art analytical calculations deviate significantly from our numerical simulations, causing a high level of uncertainty that we do not recommend this method (an upper limit of the rear contact resistance per line contact is determined to be about 2 Ω cm). In the second method, the rear line contacts are separated and measured with the TLM. Still, the series resistance loss in the base has to be quantified considering a thick base and the rear line contact geometry. We separate the base component by numerical device simulations and find that the rear contact resistance per line contact is below 0.5 Ω cm. This implies that rear contact resistance reduces cell efficiency of screen-printed PERC solar cells only by about 0.1%abs for metallization fractions higher than 3.5%, i.e., the rear contact resistance is currently no significant loss mechanism in our PERC solar cells. All of our improved evaluations lead to lower resistance values than previously reported and with a reduced uncertainty. The TLM method is suggested to be favorable.

  12. Evaluation of a High-Performance Solar Home in Loveland, Colorado: Preprint

    SciTech Connect

    Hendron, R.; Eastment, M.; Hancock, E.; Barker, G.; Reeves, P.

    2006-08-01

    Building America (BA) partner McStain Neighborhoods built the Discovery House in Loveland, Colorado, with an extensive package of energy-efficient features, including a high-performance envelope, efficient mechanical systems, a solar water heater integrated with the space-heating system, a heat-recovery ventilator (HRV), and ENERGY STAR appliances. The National Renewable Energy Laboratory (NREL) and Building Science Consortium (BSC) conducted short-term field-testing and building energy simulations to evaluate the performance of the house. These evaluations are utilized by BA to improve future prototype designs and to identify critical research needs. The Discovery House building envelope and ducts were very tight under normal operating conditions. The HRV provided fresh air at a rate of about 35 l/s (75 cfm), consistent with the recommendations of ASHRAE Standard 62.2. The solar hot water system is expected to meet the bulk of the domestic hot water (DHW) load (>83%), but only about 12% of the space-heating load. DOE-2.2 simulations predict whole-house source energy savings of 54% compared to the BA Benchmark. The largest contributors to energy savings beyond McStain's standard practice are the solar water heater, HRV, improved air distribution, high-efficiency boiler, and compact fluorescent lighting package.

  13. Evaluation of a High-Performance Solar Home in Loveland, Colorado

    SciTech Connect

    Hendron, R.; Eastment, M.; Hancock, E.; Barker, G.; Reeves, P.

    2006-01-01

    Building America (BA) partner McStain Neighborhoods built the Discovery House in Loveland, Colorado, with an extensive package of energy-efficient features, including a high-performance envelope, efficient mechanical systems, a solar water heater integrated with the space-heating system, a heat-recovery ventilator (HRV), and ENERGY STAR? appliances. The National Renewable Energy Laboratory (NREL) and Building Science Consortium (BSC) conducted short-term field-testing and building energy simulations to evaluate the performance of the house. These evaluations are utilized by BA to improve future prototype designs and to identify critical research needs. The Discovery House building envelope and ducts were very tight under normal operating conditions. The HRV provided fresh air at a rate of about 75 cfm (35 l/s), consistent with the recommendations of ASHRAE Standard 62.2. The solar hot water system is expected to meet the bulk of the domestic hot water (DHW) load (>83%), but only about 12% of the space-heating load. DOE-2.2 simulations predict whole-house source energy savings of 54% compared to the BA Benchmark [1]. The largest contributors to energy savings beyond McStain's standard practice are the solar water heater, HRV, improved air distribution, high-efficiency boiler, and compact fluorescent lighting package.

  14. Hydrogen passivation of N(+)-P and P(+)-N heteroepitaxial InP solar cell structures

    NASA Technical Reports Server (NTRS)

    Chatterjee, Basab; Davis, William C.; Ringel, Steve A.; Hoffman, Richard, Jr.

    1996-01-01

    Dislocations and related point defect complexes caused by lattice mismatch currently limit the performance of heteroepitaxial InP cells by introducing shunting paths across the active junction and by the formation of deep traps within the base region. We have previously demonstrated that plasma hydrogenation is an effective and stable means to passivate the electrical activity of such defects in specially designed heteroepitaxial InP test structures to probe hydrogen passivation at typical base depths within a cell structure. In this work, we present our results on the hydrogen passivation of actual heteroepitaxial n-p and p-n InP cell structures grown on GaAs substrates by metalorganic chemical vapor deposition (MOCVD). We have found that a 2 hour exposure to a 13.56 MHz hydrogen plasma at 275 C reduces the deep level concentration in the base regions of both n(+)-p and p(+)-n heteroepitaxial InP cell structures from as-grown values of 5-7 x 10(exp 14) cm(exp -3), down to 3-5 x 10(exp 12) cm(exp -3). All dopants were successfully reactivated by a 400 C, 5 minute anneal with no detectable activation of deep levels. One to five analysis indicated a subsequent approximately 100 fold decrease in reverse leakage current at -1 volt reverse bias, and an improved built in voltage for the p(+)-n structures. In addition to being passivated, dislocations are also shown to participate in secondary interactions during hydrogenation. We find that the presence of dislocations enhances hydrogen diffusion into the cell structure, and lowers the apparent dissociation energy of Zn-H complexes from 1.19 eV for homoepitaxial Zn-doped InP to 1.12 eV for heteroepitaxial Zn-doped InP. This is explained by additional hydrogen trapping at dislocations subsequent to the reactivation of Zn dopants after hydrogenation.

  15. Hydrogen Passivation of N(+)P and P(+)N Heteroepitaxial InP Solar Cell Structures

    NASA Technical Reports Server (NTRS)

    Chatterjee, B.; Davis, W. C.; Ringel, S. A.; Hoffman, R., Jr.

    1995-01-01

    Dislocations and related point defect complexes caused by lattice mismatch currently limit the performance of heteroepitaxial InP cells by introducing shunting paths across the active junction and by the formation of deep traps within the base region. We have previously demonstrated that plasma hydrogenation is an effective and stable means to passivate the electrical activity of such defects in specially designed heteroepitaxial InP test structures to probe hydrogen passivation at typical base depths within a cell structure. In this work, we present our results on the hydrogen passivation of actual heteroepitaxial n(+)p and p(+)n InP cell structures grown on GaAs substrates by metalorganic chemical vapor deposition (MOCVD). We have found that a 2 hour exposure to a 13.56 MHz hydrogen plasma at 275 C reduces the deep level concentration in the base regions of both n(+)p and p(+)n heteroepitaxial InP cell structures from as-grown values of 5 - 7 x 10(exp 14)/cc, down to 3 - 5 x 10(exp 12)/cc. All dopants were successfully reactivated by a 400 C, 5 minute anneal With no detectable activation of deep levels. I-V analysis indicated a subsequent approx. 100 fold decrease In reverse leakage current at -1 volt reverse bias, and an improved built in voltage for the p(+)n structures. ln addition to being passivated,dislocations are also shown to participate in secondary interactions during hydrogenation. We find that the presence of dislocations enhances hydrogen diffusion into the cell structure, and lowers the apparent dissociation energy of Zn-H complexes from 1.19 eV for homoepitaxial Zn-doped InP to 1.12 eV for heteroepitaxial Zn-doped InP. This is explained by additional hydrogen trapping at dislocations subsequent to the reactivation of Zn dopants after hydrogenation.

  16. Polybrominated diphenyl ether (PBDE) concentrations and resulting exposure in homes in California: relationships among passive air, surface wipe and dust concentrations, and temporal variability

    EPA Science Inventory

    Polybrominated diphenyl ethers (PBDEs) are used as flame retardants in furniture foam, electronics, and other home furnishings. A field study was conducted that enrolled 139 households from California, which has had more stringent flame retardant requirements than other countries...

  17. Development of a genetic algorithm optimisation tool for the early stage design of low and net-Zero Energy Solar Homes

    NASA Astrophysics Data System (ADS)

    Charron, Remi

    Homes that utilise solar thermal and solar photovoltaic (PV) technologies to generate as much energy as they consume in a year are referred to as net-Zero Energy Solar Homes (ZESH). This thesis presents the methodology used to develop a Genetic Algorithm (GA) Optimisation Tool that finds optimal configurations of low and net-zero energy solar homes taking into consideration effects from the use of different technologies, local climate, economics, and other factors. The tool links a low energy solar home model developed in TRNSYS with a GA optimisation program that automates the search for cost-effective building designs. The tool varies a predefined set of parameters including building width to length ratio, heating system type, solar thermal collector type and size, and more. The results from the TRNSYS model are compared with monitored data of an energy efficient house to verify that the model was correctly implemented. A total of 40 test cases were evaluated with the tool in order to verify the effects of climate, energy consumption target, control strategy, utility price structures, and other factors, to examine their impact on the resulting optimal design configurations. The GA program was capable of finding designs that were on average within 0.5% of the best known solution with the evaluation of only 0.00012% of the solution space. Results indicated that homes could be built with near equivalent monthly costs of conventional homes, while reducing the annual net-energy consumption by an order of magnitude. A reduction in PV system costs or the introduction of appropriate feed-in-tariffs had significant impacts on the overall cost-effectiveness of ZESH. The thesis clearly demonstrated the extent to which local climate, economic factors, and specific design constraints can have a major impact on the optimal design configuration, which limits the usefulness of generic design guidelines. The methodology developed was also a novel way of using TRNSYS for the

  18. X-ray evaluation of electronic and chemical properties and film structures in SiN passivation layer on crystalline Si solar cells

    NASA Astrophysics Data System (ADS)

    Yamashita, Yoshihiro; Ikeno, Norihiro; Tachibana, Tomihisa; Ohshita, Yoshio; Ogura, Atsushi

    2015-08-01

    We investigated the electronic chemical properties and film structures in SiN passivation layers on crystalline Si by X-ray photoelectron spectroscopy (XPS) and X-ray reflectometry (XRR). From XPS analyses, a N-rich component (N-Si-N) and oxygen mixing were observed at the interface. The longest lifetime was obtained after post deposition annealing at 600 °C, where the N-rich layer was the thinnest with small peak height. Therefore, longer lifetime could be obtained as the N concentration at the interface decreased. The film consisted of three SiN layers and one SiO2 layer, as confirmed by XRR profile fitting. From the density profiles, a longer lifetime was obtained when the density gradient in the oxygen mixing layer was small. Results of XPS and XRR suggested that N at the interface significantly affected the lifetime. We believe it is important to understand the electronic chemical properties at the passivation interface to realize high-efficiency Si solar cells.

  19. Simultaneous P and B diffusion, in-situ surface passivation, impurity filtering and gettering for high-efficiency silicon solar cells

    SciTech Connect

    Krygowski, T.; Rohatgi, A.; Ruby, D.

    1997-11-01

    A technique is presented to simultaneously diffuse boron and phosphorus in silicon, and grow an in-situ passivating oxide in a single furnace step. It is shown that limited solid doping sources made from P and B Spin-On Dopant (SOD) films can produce optimal n{sup +} and p{sup +} profiles simultaneously without the deleterious effects of cross doping. A high quality passivating oxide is grown in-situ beneath the thin ({approximately} 60 {angstrom}) diffusion glass, resulting in low J{sub o} values below 100 fA/cm{sup 2} for transparent ({approximately} 100 {Omega}/{open_square}) phosphorus and boron diffusions. For the first time it is shown that impurities present in the boron SOD film can be effectively filtered out by employing separate source wafers, resulting in bulk lifetimes in excess of 1 ms for the sample wafers. The degree of lifetime degradation in the sources is related to the gettering efficiency of boron in silicon. This novel simultaneous diffusion, in-situ oxidation, impurity filtering and gettering technique was successfully used to produce 20.3% Fz, and 19.1% Cz solar cells, in one furnace step.

  20. Passive Energy Building Design Tool

    1994-11-01

    SOLAR5 is a computer aided design tool to help architects design better, more energy efficient buildings. It is intended for use at the beginning of the design process. To get started, only four pieces of information are necessary to compute the energy needed: the square footage, the number of stories, the kind of building (such as school, home, hotel, or any one of 20 types), and its location (the program stores the temperature ranges formore » fourty major cities). Additional information may be given later to fine tune the design. An expert system using heuristics from a wide range of sources, automatically creates a passive solar baseline building from the four facts specified for that project. By modifying and adapting prior designs the user can create and work upon as many as nine schemes simultaneously. SOLAR5 can analyze the buildings thermal performance for each hour of each month and plot its total heat gain or loss as a three-dimensional surface. After reading the plot, the user can immediately redesign the building and rerun the analysis. Separate heat gain/loss surfaces can be plotted for each of the different parts of the building or schemes that add together to make up the total, including walls, roof, windows, skylights, floor, slab on grade, people, lights, equipment, and infiltration. Two different schemes can be instantly compared by asking for a three-dimensional plot showing only the difference in their performances. The objective of SOLAR5 is to allow the designer to make changes easily and quickly with detailed instantaneous pictorial feedback of the implications of the change.« less

  1. Solar-assisted electric clothes dryer using a home attic as a heat source

    SciTech Connect

    Stana, J. M.

    1983-01-01

    This study was undertaken to determine the suitability of using a southeastern home attic as a means of reducing the energy consumption of an electric clothes dryer. An inexpensive duct (duplicable for $25) was constructed to collect hot attic air from the peak of a south facing roof and introduce it into the dryer inlet. Instrumentation was added to measure inlet temperatures and operating time/energy consumption of the dryer. Standardized test loads, in addition to normal laundry, were observed over the period of one year. The heat-on time of the dryer tested was shown to be reduced .16 to .35 minutes per /sup 0/C rise in inlet temperature. Inlet temperatures produced by the attic duct peaked at 56/sup 0/C(133/sup 9/F) in May/June and 40/sup 0/C(104/sup 0/F) in February. Based on peak temperatures available between 2 and 4 pm each month, a potential 20% yearly average savings could be realized. Economic viability of the system, dependant primarily on dryer usage, can be computed using a formula derived from the test results and included in the report.

  2. Origin and elimination of photocurrent hysteresis by fullerene passivation in CH3NH3PbI3 planar heterojunction solar cells

    SciTech Connect

    Shao, Yuchuan; Xiao, Zhengguo; Bi, Cheng; Yuan, Yongbo; Huang, Jinsong

    2014-12-15

    The large photocurrent hysteresis observed in many organometal trihalide perovskite solar cells has become a major hindrance impairing the ultimate performance and stability of these devices, while its origin was unknown. Here we demonstrate the trap states on the surface and grain boundaries of the perovskite materials to be the origin of photocurrent hysteresis and that the fullerene layers deposited on perovskites can effectively passivate these charge trap states and eliminate the notorious photocurrent hysteresis. Fullerenes deposited on the top of the perovskites reduce the trap density by two orders of magnitude and double the power conversion efficiency of CH3NH3PbI3 solar cells. As a result, the elucidation of the origin of photocurrent hysteresis and its elimination by trap passivation in perovskite solar cells provides important directions for future enhancements to device efficiency.

  3. Manned exploration and exploitation of solar system: Passive and active shielding for protecting astronauts from ionizing radiation-A short overview

    NASA Astrophysics Data System (ADS)

    Spillantini, Piero

    2014-11-01

    In deep space manned missions for the exploration and exploitation of celestial bodies of Solar System astronauts are not shielded by the terrestrial magnetic field and must be protected against the action of Solar Cosmic Rays (SCRs) and Galactic Cosmic Rays (GCRs). SCRs are sporadically emitted, and in very rare but possible events, their fluence can be so high to be lethal to a unprotected crew. Their relatively low energy allows us to conceive fully passive shields, also if active systems can somewhat reduce the needed mass penalty. GCRs continuously flow without intensity peaks, and are dangerous to the health and operability of the crew in long duration (>1year) missions. Their very high energy excludes the possible use of passive systems, so that recourse must be made to electromagnetic fields for preventing ionizing particles to reach the habitat where astronauts spend most of their living and working time. A short overview is presented of the many ideas developed in last decades of last century; ideas are mainly based on very intense electrostatic shields, flowing plasma bubbles, or enormous superconducting coil systems for producing high magnetic fields. In the first decade of this century the problem began to be afforded in more realistic scenarios, taking into account the present and foreseeable possibilities of launchers (payload mass, diameter and length of the shroud of the rocket, etc.) and of assembling and/or inflating structures in space. Driving parameters are the volume of the habitat to be protected and the level of mitigation of the radiation dose to be guaranteed to the crew. Superconducting magnet systems based on multi-solenoid complexes or on one huge magnetic torus surrounding the habitat are being evaluated for defining the needed parameters: masses, mechanical structures for supporting the huge magnetic forces, needed equipments and safety systems. Technological tests are in preparation or planned for improving density of the current

  4. Enhanced Carrier Collection from CdS Passivated Grains in Solution-Processed Cu2ZnSn(S,Se)4 Solar Cells.

    PubMed

    Werner, Melanie; Keller, Debora; Haass, Stefan G; Gretener, Christina; Bissig, Benjamin; Fuchs, Peter; La Mattina, Fabio; Erni, Rolf; Romanyuk, Yaroslav E; Tiwari, Ayodhya N

    2015-06-10

    Solution processing of Cu2ZnSn(S,Se)4 (CZTSSe)-kesterite solar cells is attractive because of easy manufacturing using readily available metal salts. The solution-processed CZTSSe absorbers, however, often suffer from poor morphology with a bilayer structure, exhibiting a dense top crust and a porous bottom layer, albeit yielding efficiencies of over 10%. To understand whether the cell performance is limited by this porous layer, a systematic compositional study using (scanning) transmission electron microscopy ((S)TEM) and energy-dispersive X-ray spectroscopy of the dimethyl sulfoxide processed CZTSSe absorbers is presented. TEM investigation revealed a thin layer of CdS that is formed around the small CZTSSe grains in the porous bottom layer during the chemical bath deposition step. This CdS passivation is found to be beneficial for the cell performance as it increases the carrier collection and facilitates the electron transport. Electron-beam-induced current measurements reveal an enhanced carrier collection for this buried region as compared to reference cells with evaporated CdS. PMID:25985349

  5. New Whole-House Solutions Case Study: Hood River Passive House

    SciTech Connect

    2014-02-01

    The Hood River Passive Project was developed by Root Design Build of Hood River Oregon using the Passive House Planning Package (PHPP) to meet all of the requirements for certification under the European Passive House standards. The Passive House design approach has been gaining momentum among residential designers for custom homes and BEopt modeling indicates that these designs may actually exceed the goal of the U.S. Department of Energy's (DOE) Building America program to "reduce home energy use by 30%-50%" (compared to 2009 energy codes for new homes). This report documents the short term test results of the Shift House and compares the results of PHPP and BEopt modeling of the project. The design includes high R-Value assemblies, extremely tight construction, high performance doors and windows, solar thermal DHW, heat recovery ventilation, moveable external shutters and a high performance ductless mini-split heat pump. Cost analysis indicates that many of the measures implemented in this project did not meet the BA standard for cost neutrality. The ductless mini-split heat pump, lighting and advanced air leakage control were the most cost effective measures. The future challenge will be to value engineer the performance levels indicated here in modeling using production based practices at a significantly lower cost.

  6. Quaternary Cu2ZnSnS4 quantum dot-sensitized solar cells: Synthesis, passivation and ligand exchange

    NASA Astrophysics Data System (ADS)

    Bai, Bing; Kou, Dongxing; Zhou, Wenhui; Zhou, Zhengji; Tian, Qingwen; Meng, Yuena; Wu, Sixin

    2016-06-01

    The quaternary Cu2ZnSnS4 (CZTS) QDs had been successfully introduced into quantum dot-sensitized solar cells (QDSC) via hydrolysis approach in our previous work [Green Chem. 2015, vol. 17, p. 4377], but the obtained cell efficiency was still limited by low open-circuit voltage and fill factor. Herein, we use 1-dodecanethiol (DDT) as capping ligand for fairly small-sized CZTS QDs synthesis to improve their intrinsic properties. Since this strong bonded capping ligand can not be replaced by 3-mercaptopropionic acid (MPA) directly, the nature cation (Cu, Zn or Sn)-DDT units of QDs are first exchanged by the preconjugated Cd-oleate via successive ionic layer adsorption and reaction (SILAR) procedure accompanied with the formation of a core/shell structure. The weak bonded oleic acid (OA) can be finally replaced by MPA and the constructed water soluble CZTS/CdSe QDSC achieves an impressive conversion efficiency of 4.70%. The electron transport and recombination dynamic processes are confirmed by intensity-modulated photocurrent spectroscopy (IMPS)/intensity-modulated photovoltage spectroscopy (IMVS) measurements. It is found that the removal of long alkyl chain is conducive to improve the electron transport process and the type-II core/shell structure is beneficial to accelerate electron transport and retard charge recombination. This effective ligand removal strategy is proved to be more convenient for the applying of quaternary QDs in QDSC and would boost a more powerful efficiency in the future work.

  7. a Study of the Home Heating Index and Comparison with Other Energy-Efficiency Indices.

    NASA Astrophysics Data System (ADS)

    Huebner, Jonathan Daniel

    The Home Heating Index (HHI), with units of Btu/F(DEGREES) -day-ft('2) or W/C(DEGREES)-m('2), and related quantities have been used to evaluate the energy-efficiency of homes in Ames, Iowa during the winter of 1984-85. From these measurements, it has been discovered that the HHI can be determined to within about 10% when the energy consumption of a house is monitored for three days. However, the amount of solar radiation significantly affected the HHI of homes with a large south-glazing area, and wind speed similarly affected the HHI of homes with a high air infiltration rate. A comparison of the HHI with other indices currently in use shows that the HHI is the only consistent index when the average inside temperature of a building or its internal heat gain is varied. Most indices are flawed in that they do not take the efficiency of the heating system into consideration, or they put too much emphasis on the solar heat input. A calculation of HHI values for different types of passive solar homes from across the United States has shown that the HHI can be applied to these homes as an indicator of energy-efficiency, and that most of these homes are indeed energy-efficient.

  8. New Whole-House Solutions Case Study: Tommy Williams Homes Initial Performance of Two Zero Energy Homes, Gainesville, Florida

    SciTech Connect

    none,

    2011-11-01

    Tommy Williams Homes worked with PNNL, Florida HERO, Energy Smart Home Plans, and Florida Solar Energy Center to design and test two zero energy homes. Energy use was 30% lower in one home and 60% lower in the other.

  9. NREL/Habitat for Humanity Zero Energy Home: A Cold-Climate Case Study for Affordable Zero Energy Homes

    SciTech Connect

    Norton, P.; Christensen, C.; Hancock, E.; Barker, G.; Reeves, P.

    2008-06-01

    The design of this 1,280-square-foot, three-bedroom Habitat for Humanity of Metro Denver zero energy home carefully combines envelope efficiency, efficient equipment, appliances and lighting, and passive and active solar features to reach the zero energy goal. The home was designed with an early version (July 22, 2004) of the BEOpt building optimization software; DOE2 and TRNSYS were used to perform additional analysis. This engineering approach was tempered by regular discussions with Habitat construction staff and volunteers. These discussions weighed the applicability of the optimized solutions to the special needs and economics of a Habitat house--moving the design toward simple, easily maintained mechanical systems and volunteer-friendly construction techniques. A data acquisition system was installed in the completed home to monitor its performance.

  10. DOE Challenge Home Case Study: e2 Homes – Winter Park, Florida

    SciTech Connect

    none,

    2013-01-01

    This Challenge Home case study describes the first certified DOE Challenge Home as constructed by e2 Homes. Completed in May 2012, the “Wilson Residence” in Winter Park, Florida, is a 4,305-ft2 custom home that scores a HERS 57 without solar and a better than zero net-energy HERS -7 with solar.

  11. Spray-roof cooling system-analysis: cooling concept integration, Phase I. Passive and hybrid solar manufactured building project. Project status report No. 1

    SciTech Connect

    Huffman, J. B.; Lindsey, L. L.; Snyder, M. K.

    1981-03-10

    The development of a roof spray system for passive/hybrid building cooling is described. Progress to date in defining and evaluating the issues and constraints relevant to spray roof cooling is described in the context of Butler's passive/hybrid manufactured buildings development program. (MHR)

  12. Climate-Specific Passive Building Standards

    SciTech Connect

    Wright, Graham S.; Klingenberg, Katrin

    2015-07-29

    In 2012, the U.S. Department of Energy (DOE) recognized the value of performance-based passive building standards when it joined with Passive House Institute US (PHIUS) to promote DOE’s Challenge Home program in tandem with the PHIUS+ Certification program. Since then, the number of passive building projects that have been certified under the partnership has grown exponentially because of some synergy. Passive building represents a well-developed approach to arrive at the envelope basis for zero energy and energy-positive projects by employing performance-based criteria and maximizing cost-effective savings from conservation before implementing renewable energy technologies. The Challenge Home program evolved into the Zero Energy Ready Home (ZERH) program in a move toward 1) attaining zero energy and 2) including active renewable energy generation such as photovoltaics (PV)—toward the zero energy goal.

  13. Passive solar in tornado alley

    SciTech Connect

    Kriescher, P.

    2000-02-01

    The renewable energy and energy efficiency industries have long relied on entrepreneurial individuals with a passion for integrating clean energy alternatives into residential and commercial construction. Most of these individuals were drawn into sustainable energy design during time of inflationary energy prices (e.g., the 1973 oil crisis), when government and industry were investing in clean energy technologies. Some of the best and brightest maintained their enthusiasm for high quality, low energy building design--even as government and industry support slowed--and worked tirelessly toward making sustainable design viable in the marketplace.

  14. Experimenting with Photoelectrochemical Cells in Drinking Straws: Practical Aids for Learning about Solar Energy in School or at Home

    ERIC Educational Resources Information Center

    Appleyard, S. J.

    2008-01-01

    Photoelectrochemical cells using dye-sensitized ZnO with a Cu[superscript 2+]/Fe[superscript 2+]/Fe[superscript 3+] electrolyte can be easily made at home or in a school classroom with household chemicals and other readily available materials. The cells, which are made with wire housed within plastic drinking straws, have open-circuit voltages of…

  15. DOE Zero Energy Ready Home Case Study: Clifton View Homes, Coupeville, Washington

    SciTech Connect

    none,

    2013-09-01

    Ted Clifton, founder of Clifton View Homes, achieved an impressive Home Energy Rating System (HERS) score of 34 (without solar panels) on a two-story home completed in July 2011 that also earned him his first Challenge Home certification from the U.S. Department of Energy (DOE). This home also garnered a 2013 Housing Innovation Award in the "systems builder" category.

  16. Passive Accelerometer

    NASA Technical Reports Server (NTRS)

    Naumann, Robert J.; Baugher, Charles; Alexander, Iwan

    1992-01-01

    Motion of ball in liquid indicates acceleration. Passive accelerometer measures small accelerations along cylindrical axis. Principle of operation based on Stokes' law. Provides accurate measurements of small quasi-steady accelerations. Additional advantage, automatically integrates out unwanted higher-frequency components of acceleration.

  17. NCSU solar energy and conservation house. Final report

    SciTech Connect

    Not Available

    1981-10-01

    A passive solar energy house has been built adjacent to the NCSU McKimmon Continuing Education Center. The house contains a two-story embedded sunspace, two Trombe walls, active solar hot water heating, thermal storage in a rock filled ceiling/floor, and numerous research treatments, and energy conservation features. (See attached photo brochure; Appendix 1). The house is completely decorated and furnished in an attractive manner and the exterior architecture is traditional and has broad consumer appeal. It is also thoroughly instrumented to monitor performance. The house is open to the public on weekends and numerous people come to visit on their own initiative and others take advantage of the close proximity to McKimmon while there attending conferences. The house will influence and motivate large numbers of people to consider solar and energy conservation facets in their homes and will provide data to substantiate performance to prospective home buyers and meaningful data on design and construction for builders.

  18. Impact of Sn(S,Se) secondary phases in Cu2ZnSn(S,Se)4 solar cells: a chemical route for their selective removal and absorber surface passivation.

    PubMed

    Xie, Haibing; Sánchez, Yudania; López-Marino, Simón; Espíndola-Rodríguez, Moisés; Neuschitzer, Markus; Sylla, Diouldé; Fairbrother, Andrew; Izquierdo-Roca, Victor; Pérez-Rodríguez, Alejandro; Saucedo, Edgardo

    2014-08-13

    The control and removal of secondary phases is one of the major challenges for the development of Cu2ZnSn(S,Se)4 (CZTSSe)-based solar cells. Although etching processes have been developed for Cu(S,Se), Zn(S,Se), and CuSn(S,Se) secondary phases, so far very little attention has been given to the role of Sn(S,Se). In this paper, we report a chemical route using a yellow (NH4)2S solution to effectively remove Sn(S,Se). We found that Sn(S,Se) can form on the surface either because of stoichiometric deviation or by condensation. After etching, the efficiency of devices typically increases between 20 and 65% relative to the before etch efficiencies. We achieved a maximum 5.9% efficiency in Se-rich CZTSSe-based devices. It is confirmed that this feature is related not only to the removal of Sn(S,Se) but also to the unexpected passivation of the surface. We propose a phenomenological model for this passivation, which may open new perspectives for the development of CZTSSe-based solar cells. PMID:25033026

  19. Impact of Sn(S,Se) secondary phases in Cu2ZnSn(S,Se)4 solar cells: a chemical route for their selective removal and absorber surface passivation.

    PubMed

    Xie, Haibing; Sánchez, Yudania; López-Marino, Simón; Espíndola-Rodríguez, Moisés; Neuschitzer, Markus; Sylla, Diouldé; Fairbrother, Andrew; Izquierdo-Roca, Victor; Pérez-Rodríguez, Alejandro; Saucedo, Edgardo

    2014-08-13

    The control and removal of secondary phases is one of the major challenges for the development of Cu2ZnSn(S,Se)4 (CZTSSe)-based solar cells. Although etching processes have been developed for Cu(S,Se), Zn(S,Se), and CuSn(S,Se) secondary phases, so far very little attention has been given to the role of Sn(S,Se). In this paper, we report a chemical route using a yellow (NH4)2S solution to effectively remove Sn(S,Se). We found that Sn(S,Se) can form on the surface either because of stoichiometric deviation or by condensation. After etching, the efficiency of devices typically increases between 20 and 65% relative to the before etch efficiencies. We achieved a maximum 5.9% efficiency in Se-rich CZTSSe-based devices. It is confirmed that this feature is related not only to the removal of Sn(S,Se) but also to the unexpected passivation of the surface. We propose a phenomenological model for this passivation, which may open new perspectives for the development of CZTSSe-based solar cells.

  20. Impact of Al passivation and cosputter on the structural property of β-FeSi2 for Al-doped β-FeSi2/n-Si(100) based solar cells application.

    PubMed

    Dalapati, Goutam Kumar; Kumar, Avishek; Tan, Cheng Cheh; Liew, Siao Li; Sonar, Prashant; Seng, Hwee Leng; Hui, Hui Kim; Tripathy, Sudhiranjan; Chi, Dongzhi

    2013-06-26

    The aluminum (Al) doped polycrystalline p-type β-phase iron disilicide (p-β-FeSi2) is grown by thermal diffusion of Al from Al-passivated n-type Si(100) surface into FeSi2 during crystallization of amorphous FeSi2 to form a p-type β-FeSi2/n-Si(100) heterostructure solar cell. The structural and photovoltaic properties of p-type β-FeSi2/n-type c-Si structures is then investigated in detail by using X-ray diffraction, Raman spectroscopy, transmission electron microscopy analysis, and electrical characterization. The results are compared with Al-doped p-β-FeSi2 prepared by using cosputtering of Al and FeSi2 layers on Al-passivated n-Si(100) substrates. A significant improvement in the maximum open-circuit voltage (Voc) from 120 to 320 mV is achieved upon the introduction of Al doping through cosputtering of Al and amorphous FeSi2 layer. The improvement in Voc is attributed to better structural quality of Al-doped FeSi2 film through Al doping and to the formation of high quality crystalline interface between Al-doped β-FeSi2 and n-type c-Si. The effects of Al-out diffusion on the performance of heterostructure solar cells have been investigated and discussed in detail.

  1. [Passive smoking].

    PubMed

    Grandjean, E; Weber, A; Fischer, T

    1979-03-01

    Passive smoking is the involuntary inspiration of smoky indoor air. Based on the information available today, it may be assumed that passive smoking normally is no health hazard as far as the classical smoker's diseases (lung cancer, myocardial infarct, etc.) are concerned. Nevertheless, it is probable that irritations caused by tobacco smoke have an unfavorable influence on the health of small children and that of already sick persons. The main problem of passive smoking is annoyance due to odor and irritations of eyes and respiratory organs. Our investigations in a climatic chamber with healthy subjects show that air pollution caused by tobacco smoke as indicated by 5 ppm CO leads to marked eye irritations--objectively as well as subjectively--in 15 to 20% of the subjects. This corresponds to smoking 10 cigarettes per hour in a small room with an air ventilation rate of four times per hour. If air pollution caused by tobacco smoke lies below the level of 2 ppm CO, irritations and annoyance for healthy persons are regarded as low and tolerable. This corresponds to about four cigarettes per hour under the same circumstances.

  2. Solar Systems

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The solar collectors shown are elements of domestic solar hot water systems produced by Solar One Ltd., Virginia Beach, Virginia. Design of these systems benefited from technical expertise provided Solar One by NASA's Langley Research Center. The company obtained a NASA technical support package describing the d e sign and operation of solar heating equipment in NASA's Tech House, a demonstration project in which aerospace and commercial building technology are combined in an energy- efficient home. Solar One received further assistance through personal contact with Langley solar experts. The company reports that the technical information provided by NASA influenced Solar One's panel design, its selection of a long-life panel coating which increases solar collection efficiency, and the method adopted for protecting solar collectors from freezing conditions.

  3. Cold-Climate Case Study for Affordable Zero Energy Homes

    SciTech Connect

    Norton, P.; Christensen, C.

    2006-01-01

    This project, supported by the U.S. Department of Energy's Building America Program, is a case study in reaching zero energy within the affordable housing sector in cold climates. The design of the 1200 square foot, 3-bedroom Denver zero energy home carefully combines envelope efficiency, efficient equipment, appliances and lighting, and passive and active solar features to reach the zero energy goal. The home was designed using an early version of the BEOpt building optimization software with additional analysis using DOE2. This engineering approach was tempered by regular discussions with Habitat construction staff and volunteers. These discussions weighed the applicability of the optimized solutions to the special needs and economics of a Habitat house--moving the design towards simple, easily maintained mechanical systems and volunteer-friendly construction techniques.

  4. Solar heating and you

    SciTech Connect

    1994-08-01

    This fact sheet for use with primary school classes describes what solar collectors are and how they work, passive solar rooms, flat-plate collectors, and why one should use solar heating systems. Making a solar air heater is described step-by-step with illustrations. A resource list for both students and teachers is provided for further information.

  5. Solar still. Final report

    SciTech Connect

    Adams, W.D.

    1983-07-20

    Passive solar heating was used in a still in which a packed column packed with popped popcorn separates the alcohol and water vapors. The still's performance was not satisfactory, and it is concluded that passive solar heating could have been better used to preheat makeup water for the fermentation process and to maintain proper fermentation temperatures during the winter. (LEW)

  6. Establish feasibility for providing passive cooling with solar updraft and evaporative downdraft chimneys. Final report, June 15, 1984--December 31, 1987

    SciTech Connect

    Cunningham, W.A.; Mignon, G.V.; Thompson, T.L.

    1987-12-31

    Natural draft towers can be used for cooling and ventilating structures. From an operational perspective, the downdraft evaporatively cooled tower is preferred for a dry climate. Solar chimneys, when used alone, tend to require an excessively large solar collector area when appreciable quantities of air must be moved. When used in combination with a downdraft tower, the roof and attic of buildings may assist the solar chimney and their use becomes more attractive. Both a frame building and a greenhouse were successfully cooled during this program. The economics of the downdraft tower compare favorably with conventional evaporative cooling for some application.

  7. Establish feasibility for providing passive cooling with solar updraft and evaporate downdraft chimneys. Final report, June 15, 1984--December 31, 1987

    SciTech Connect

    Cunningham, W.A.; Mignon, G.V.; Thompson, T.L.

    1987-12-31

    Natural draft towers can be used for cooling and ventilating structures. From an operational perspective, the downdraft evaporatively cooled tower is preferred for a dry climate. Solar chimneys, when used alone, tend to require an excessively large solar collector area when appreciable quantities of air must be moved. When used in combination with a downdraft tower, the roof and attic of buildings may assist the solar chimney and their use becomes more attractive. Both a frame building and a greenhouse were successfully cooled during this program. The economics of the downdraft tower compare favorably with conventional evaporative cooling for some applications.

  8. Solar Technologies

    ERIC Educational Resources Information Center

    von Hippel, Frank; Williams, Robert H.

    1975-01-01

    As fossil fuels decrease in availability and environmental concerns increase, soalr energy is becoming a potential major energy source. Already solar energy is used for space heating in homes. Proposals for solar-electric generating systems include land-based or ocean-based collectors and harnessing wind and wave power. Photosynthesis can also…

  9. Improvement in passivation quality and open-circuit voltage in silicon heterojunction solar cells by the catalytic doping of phosphorus atoms

    NASA Astrophysics Data System (ADS)

    Tsuzaki, Shogo; Ohdaira, Keisuke; Oikawa, Takafumi; Koyama, Koichi; Matsumura, Hideki

    2015-07-01

    We apply phosphorus (P) doping to amorphous silicon (a-Si)/crystalline silicon (c-Si) heterojunction solar cells realized by exposing c-Si to P-related radicals generated by the catalytic cracking of PH3 molecules (Cat-doping). An ultrathin n+-layer formed by P Cat-doping acts to improve the effective minority carrier lifetime (τeff) and implied open-circuit voltage (implied Voc) owing to its field effect by which minority holes are sent back from an a-Si/c-Si interface. An a-Si/c-Si heterojunction solar cell with a P Cat-doped layer shows better solar cell performance, particularly in Voc, than the cell without P Cat-doping. This result demonstrates the feasibility of applying Cat-doping to a-Si/c-Si heterojunction solar cells, owing to the advantage of the low-temperature (<200 °C) process of Cat-doping.

  10. International Energy Agency (IEA) Task VIII passive and hybrid solar low energy buildings: Residential design-build projects: Archetype/Santa Fe development project summary

    SciTech Connect

    Frey, D.J.; Gregerson, J.M.

    1989-05-01

    Included in this report are a description of the building, significant steps in the design process, an overview of the monitoring process, and results from the thermal monitoring. Also included are the responses provided by the owner/occupant to questions on the ''Class C'' questionnaire. This is the same questionnaire that was used in the Department of Energy's Class C passive building performance evaluation program in the early 1980s. 9 refs., 8 tabs.

  11. HOME ENERGY SUPPLY-DEMAND ANALYSIS FOR COMBINED SYSTEM OF SOLAR HEAT COLLECTOR AND HEAT PUMP WATER HEATER

    NASA Astrophysics Data System (ADS)

    Ikegami, Takashi; Kataoka, Kazuto; Iwafune, Yumiko; Ogimoto, Kazuhiko

    In order to evaluate effectiveness of a combined system of solar heat collecctor (SHC) and heat pump water heater (HPWH), optimum operation scheduling moldel of domestic electric appliances using the mixed integer linear programming was enhanced. Applying this model with one house data in Tokyo, it was found that the combined system of the SHC and the HPWH has the enough energy-saving and CO2 emission reduction potential under the existing electricity late and the operation method of the HPWH. Furthermore, the calculation results under the future system show that the combined system of the SHC and the HPWH has also the reduction effect of reverse power flow from residential photovoltaic system.

  12. Sunspot Time Series: Passive and Active Intervals

    NASA Astrophysics Data System (ADS)

    Zięba, S.; Nieckarz, Z.

    2014-07-01

    Solar activity slowly and irregularly decreases from the first spotless day (FSD) in the declining phase of the old sunspot cycle and systematically, but also in an irregular way, increases to the new cycle maximum after the last spotless day (LSD). The time interval between the first and the last spotless day can be called the passive interval (PI), while the time interval from the last spotless day to the first one after the new cycle maximum is the related active interval (AI). Minima of solar cycles are inside PIs, while maxima are inside AIs. In this article, we study the properties of passive and active intervals to determine the relation between them. We have found that some properties of PIs, and related AIs, differ significantly between two group of solar cycles; this has allowed us to classify Cycles 8 - 15 as passive cycles, and Cycles 17 - 23 as active ones. We conclude that the solar activity in the PI declining phase (a descending phase of the previous cycle) determines the strength of the approaching maximum in the case of active cycles, while the activity of the PI rising phase (a phase of the ongoing cycle early growth) determines the strength of passive cycles. This can have implications for solar dynamo models. Our approach indicates the important role of solar activity during the declining and the rising phases of the solar-cycle minimum.

  13. Building interest in solar energy

    SciTech Connect

    1996-12-31

    Today`s solar technology and growing availability of energy-efficient mortgages offer advantages to home builders around the country. This article describes the different types of solar technology as well as the financing incentives that reward buyers of energy-efficient homes. Inset information includes consumer survey results about consumer interest in buying homes with solar features, current extra expense, and future savings, established home energy rating programs, and individual state financial incentives.

  14. Nursing Homes

    MedlinePlus

    ... our e-newsletter! Aging & Health A to Z Nursing Homes Basic Facts & Information Nursing homes have changed ... physical health and/or mental disabilities. Is a Nursing Home Right for You? Almost half of all ...

  15. Home sweet medical home.

    PubMed

    Sorrel, Amy Lynn

    2014-11-01

    Starting with a solid primary care foundation, the patient-centered medical home has become a hot commodity for making health care more efficient and effective and less fragmented and costly. Whether the enhanced primary care model lives up to its promise is still up for debate, based on the available research. Still, policymakers, payers, and physician practices are increasingly taking the bet.

  16. Energy reduction using biofiltration in a highly efficient residential home

    NASA Astrophysics Data System (ADS)

    Rodgers, Kevin L.

    The objective of this research was to design, demonstrate, and monitor the Biowall; a novel system for improving indoor air quality in a residential building, which has the potential to save energy compared to traditional air quality control. The Biowall was integrated into the heating, ventilation, and air-condition system of a high performance home and utilized plants as a passive filter system to remove volatile organic compounds from the interior space of the home. The testing environment in this study was a 984 square foot efficient residential home constructed for the U.S. Department of Energy Solar Decathlon 2011 competition. A number of sensors were installed in the home to monitor the operation of the wall including temperature, relative humidity, carbon dioxide, and total volatile organic compound (TVOC) sensors. The main outcomes of the project included the design and construction of a test platform for the current study and future research, energy results that showed as high as 160% energy savings over a 1 week test period and $170 per year in cost savings versus a traditional ventilation strategy, and lessons learned and suggestions for future research.

  17. Investigation of anodic and chemical oxides grown on p-type InP with applications to surface passivation for n(+)-p solar cell fabrication

    NASA Technical Reports Server (NTRS)

    Faur, Maria; Faur, Mircea; Goradia, Manju; Goradia, Chandra; Jenkins, Phillip; Jayne, Douglas; Weinberg, Irving

    1991-01-01

    Most of the previously reported InP anodic oxides were grown on a n-type InP with applications to fabrication of MISFET structures and were described as a mixture of In2O3 and P2O5 stoichiometric compounds or nonstoichiometric phases which have properties similar to crystalline compounds In(OH)3, InPO4, and In(PO3)3. Details of the compositional change of the anodic oxides grown under different anodization conditions were previously reported. The use of P-rich oxides grown either by anodic or chemical oxidation are investigated for surface passivation of p-type InP and as a protective cap during junction formation by closed-ampoule sulfur diffusion. The investigation is based on but not limited to correlations between PL intensity and X-ray photoelectron spectroscopy (XPS) chemical composition data.

  18. Solar Design Workbook

    SciTech Connect

    Franta, G.; Baylin, F.; Crowther, R.; Dubin, F.; Grace, A., Griffith, J.W.; Holtz, M.; Kutscher, C.; Nordham, D.; Selkowitz, S.; Villecco, M.

    1981-06-01

    This Solar Design Workbook presents solar building design applications for commercial buildir^s. The book is divided into four sections. The first section describes the variety of solar applications in buildings including conservation aspects, solar fundamentals, passive systems, active systems, daylighting, and other solar options. Solar system design evaluation techniques including considerations for building energy requirements, passive systems, active systems, and economics are presented in Section II. The third section attempts to assist the designer in the building design process for energy conservation and solar applications including options and considerations for pre-design, design, and post-design phases. The information required for the solar design proee^ has not been fully developed at this time. Therefore, Section III is incomplete, but an overview of the considerations with some of the design proces elements is presented. Section IV illustrates ease studies that utilize solar applications in the building design.

  19. Fundamental studies of passivity and passivity breakdown

    SciTech Connect

    Macdonald, D.D.; Urquidi-Macdonald, M.; Song, H.; Biaggio-Rocha, S.; Searson, P.

    1991-11-01

    This report summarizes the findings of our fundamental research program on passivity and passivity breakdown. During the past three and one half years in this program (including the three year incrementally-funded grant prior to the present grant), we developed and experimentally tested various physical models for the growth and breakdown of passive films on metal surfaces. These models belong to a general class termed point defects models'' (PDMs), in which the growth and breakdown of passive films are described in terms of the movement of anion and cation vacancies.

  20. Solar Spots - Activities to Introduce Solar Energy into the K-8 Curricula.

    ERIC Educational Resources Information Center

    Longe, Karen M.; McClelland, Michael J.

    Following an introduction to solar technology which reviews solar heating and cooling, passive solar systems (direct gain systems, thermal storage walls, sun spaces, roof ponds, and convection loops), active solar systems, solar electricity (photovoltaic and solar thermal conversion systems), wind energy, and biomass, activities to introduce solar…

  1. Environmental partnership, Cream Ridge, New Jersey: Solar-energy-system performance evaluation, October 1981 through March 1982

    NASA Astrophysics Data System (ADS)

    Kendall, P. W.

    The Environmental Partnership site (also known as the Bonillia Home) is a two story, single family home on a wooded lot in New Jersey. The wood platform framed house uses three major passive solar energy systems a 168 square foot sunspace, a 344 square foot Trombe wall, and a breadbox type passive solar hot water heater. The system was designed to provide 75% of the total load at the site, but only achieved 30%. Storage is in a 50,000 pound concrete wall 12 inches thick and in 32 3 foot phase change rods. Auxiliary systems include a dual fuel wood/propane furnace, wood stove, 50 gallon auxiliary water heater with propane fuel, and a cooling fan. Monthly performance data are tabulated for the overall solar heating system and for the individual components - Trombe wall, sunspace, storage, water heater, and space heating subsystem. Monthly data are also tabulated for weather, energy savings, and the passive solar system environment. Typical system operation is illustrated by graphs of temperatures at various places in the system versus time for a typical day. The system operating sequence is also illustrated by a bar chart of the operation of the wood/propane furnace and the fan.

  2. Home Care

    MedlinePlus

    ... Help Related Topics Assisted Living Community-Based Care Nursing Homes Related Video Join our e-newsletter! Aging & Health A to Z Home Care Basic Facts & Information Role of Health Care Professionals in Home Care Your physician is the leader ...

  3. The Design of a Smokefree Home Leaflet and Home Pack: A Guernsey Case Study

    ERIC Educational Resources Information Center

    Amey, Vidya

    2011-01-01

    Purpose: This paper aims to explore the beliefs and attitudes of young mothers in relation to smokefree homes and passive smoke in Guernsey, and to encourage them to contribute to the designing of a smokefree home leaflet and pack aimed at young mothers. Design/methodology/approach: Semi-structured interviews were conducted with 11 participants…

  4. Fundamental studies on passivity and passivity breakdown

    SciTech Connect

    Macdonald, D.D.; Urquidi-Macdonald, M.

    1993-06-01

    Using photoelectrochemical impedance and admittance spectroscopies, a fundamental and quantitative understanding of the mechanisms for the growth and breakdown of passive films on metal and alloy surfaces in contact with aqueous environments is being developed. A point defect model has been extended to explain the breakdown of passive films, leading to pitting and crack growth and thus development of damage due to localized corrosion.

  5. DOE Zero Energy Ready Home Case Study: Garbett Homes, Herriman, Utah

    SciTech Connect

    none,

    2013-09-01

    As the first net zero-energy production home certified in Utah, this house incorporates two 94% efficient tankless water heaters and two roof-mounted solar panels that preheat the home's water supply. This home won a 2013 Housing Innovation Award in the production builder category.

  6. Tropospheric Passive Remote Sensing

    NASA Technical Reports Server (NTRS)

    Keafer, L. S., Jr. (Editor)

    1982-01-01

    The long term role of airborne/spaceborne passive remote sensing systems for tropospheric air quality research and the identification of technology advances required to improve the performance of passive remote sensing systems were discussed.

  7. Cold-Climate Case Study for Affordable Zero Energy Homes: Preprint

    SciTech Connect

    Norton, P.; Christensen, C.

    2006-07-01

    This project, supported by the U.S. Department of Energy's Building America Program, is a case study in reaching zero energy within the affordable housing sector in cold climates. The design of the 1200 square foot, 3-bedroom Denver zero energy home carefully combines envelope efficiency, efficient equipment, appliances and lighting, and passive and active solar features to reach the zero energy goal. The home was designed using an early version of the BEOpt building optimization software with additional analysis using DOE2. This engineering approach was tempered by regular discussions with Habitat construction staff and volunteers. These discussions weighed the applicability of the optimized solutions to the special needs and economics of a Habitat house--moving the design towards simple, easily maintained mechanical systems and volunteer-friendly construction techniques.

  8. Build a Solar Greenhouse.

    ERIC Educational Resources Information Center

    Conservation and Renewable Energy Inquiry and Referral Service (DOE), Silver Spring, MD.

    Attached solar greenhouses are relatively inexpensive and easy to build; they can provide additional heat to homes all winter as well as fresh vegetables and flowers. This bulletin: (1) describes the characteristics of a solar greenhouse; (2) provides a checklist of five items to consider before building a solar greenhouse; (3) describes the four…

  9. Interlanguage Passive Construction

    ERIC Educational Resources Information Center

    Simargool, Nirada

    2008-01-01

    Because the appearance of the passive construction varies cross linguistically, differences exist in the interlanguage (IL) passives attempted by learners of English. One such difference is the widely studied IL pseudo passive, as in "*new cars must keep inside" produced by Chinese speakers. The belief that this is a reflection of L1 language…

  10. Solar performance: results from the field

    SciTech Connect

    Adams, J.A.

    1982-07-01

    Actual monitored data are presented on 7 homes and an office complex to illustrate energy savings possible through the use of solar energy and energy conservation. In the Brookhaven house (superinsulated) a Trombe wall is shown to be superior to a sunspace. Energy-Efficient Residence I (Mt. Airy, MD) is compared to a conventional house next door and found to use 70% less energy for heating and 31% less energy for cooling. Energy-Efficient Residence II (Damascus, MD) is a two-story residence using passive and hybrid solar space heating, rockbin heat storage, greywater recycling and an earth-source heat pump. It's energy heating costs are reported at $120/yr. In an office complex in Taos, NM solar energy was reported to provide 67% of the heating and a large fraction of the lighting requirements. The Mastin Double-Envelope House in Middletown, RI is described as operating quite effectively although some problems remain. Rymark I, II, and III (Frederick, MD) are described as modular homes with various amounts of north and south glazing, and differing amounts of insulation and thermal mass. One finding is that 85 ft/sup 2/ of glass and R-5 window insulation saves the same amount of energy as adding 125 ft/sup 2/ of south glass and eutectic salts for thermal mass, but costs $2200 less. (MJJ)

  11. Cloud Liquid Water Path Comparisons from Passive Microwave and Solar Reflectance Satellite Measurements: Assessment of Sub-Field-of-View Cloud Effects in Microwave Retrievals

    NASA Technical Reports Server (NTRS)

    Greenwald, Thomas J.; Christopher, Sundar A.; Chou, Joyce

    1997-01-01

    Satellite observations of the cloud liquid water path (LWP) are compared from special sensor microwave imager (SSM/I) measurements and GOES 8 imager solar reflectance (SR) measurements to ascertain the impact of sub-field-of-view (FOV) cloud effects on SSM/I 37 GHz retrievals. The SR retrievals also incorporate estimates of the cloud droplet effective radius derived from the GOES 8 3.9-micron channel. The comparisons consist of simultaneous collocated and full-resolution measurements and are limited to nonprecipitating marine stratocumulus in the eastern Pacific for two days in October 1995. The retrievals from these independent methods are consistent for overcast SSM/I FOVS, with RMS differences as low as 0.030 kg/sq m, although biases exist for clouds with more open spatial structure, where the RMS differences increase to 0.039 kg/sq m. For broken cloudiness within the SSM/I FOV the average beam-filling error (BFE) in the microwave retrievals is found to be about 22% (average cloud amount of 73%). This systematic error is comparable with the average random errors in the microwave retrievals. However, even larger BFEs can be expected for individual FOVs and for regions with less cloudiness. By scaling the microwave retrievals by the cloud amount within the FOV, the systematic BFE can be significantly reduced but with increased RMS differences of O.046-0.058 kg/sq m when compared to the SR retrievals. The beam-filling effects reported here are significant and are expected to impact directly upon studies that use instantaneous SSM/I measurements of cloud LWP, such as cloud classification studies and validation studies involving surface-based or in situ data.

  12. Final report for the DOE Suede Project, (solar utilization/economic development and employment project)

    SciTech Connect

    Katz, G.; Zahigian, E. Jr.

    1983-10-19

    The purpose of this solar energy project was to design, manufacture, install, maintain and evaluate solar heating systems in order to stimulate community acceptance of the practicality of solar applications, reduce non-renewable energy resource consumption, and decrease residential expenditures for energy. The project also provided skill training and experience for CETA employees in the design, manufacture, and installation of solar energy equipment systems. CDC's contract had four separate solar energy projects; namely: Domestic Water Heating Systems for four Single-Family Homes; Domestic Water Heating for an industrial building; Domestic Water Heating for a (4) unit apartment complex (includes (12) supplemental space heating units); and Integral Passive Water Heaters and Energy Conservation Devices for (8) one bedroom homes. CDC staff designed all solar systems and CETA trainees (County and City vocational training program enrollees) under staff guidance manufactured, installed, and maintained all the solar energy systems. This report describes each of the energy projects and explains the design, manufacture and installation of each system. Each system is evaluated on the basis of energy savings, aquisition and maintenance costs, operation, service requirements and reliability.

  13. [Fundamental studies of passivity and passivity breakdown

    SciTech Connect

    Macdonald, D.D.

    1993-07-01

    We developed and experimentally tested physical models for growth and breakdown of passive films on metal surfaces. These models are ``point defect models,`` in which the growth and breakdown are described in terms of movement of anion and cation vacancies. The work during the past 5 years resulted in: theory of growth and breakdown of passive films, theory of corrosion-resistant alloys, electronic structure of passive films, and estimation of damage functions for energy systems. Proposals are give for the five ongoing tasks. 10 figs.

  14. Introduction to solar technology

    NASA Astrophysics Data System (ADS)

    Fisk, M. J.; Anderson, H. C. W.

    An introductory textbook of the basic theoretical, engineering, and architectural principles of solar energy conversion systems is presented, with an emphasis on building heating applications. Attention is given to solar radiation measurement and heat transfer by radiation, convection, and conduction. The functional characteristics of flat plate collectors are explored, together with heat storage technologies, designs, and controls. Consideration is given to parameters affecting system design, selection, and optimization, and passive solar building heating systems are described, including architectural details. Concentrating solar collectors are discussed in conjunction with heat engines and air conditioning units. Finally, solar energy electricity generating technologies are reviewed, as are factors affecting the future uses of solar energy.

  15. Solar ponds

    SciTech Connect

    Jayadev, T.S.; Edesess, M.

    1980-04-01

    This report first describes the different types of solar ponds including the nonconvecting salt gradient pond and various saltless pond designs. It then discusses the availability and cost of salts for salt gradient ponds, and compares the economics of salty and saltless ponds as a function of salt cost. A simple computational model is developed to approximate solar pond performance. This model is later used to size solar ponds for district heating and industrial process heat applications. For district heating, ponds are sized to provide space conditioning for a group of homes, in different regions of the United States. Size requirements is on the order of one acre for a group of 25 to 50 homes. An economic analysis is performed of solar ponds used in two industrial process heat applications. The analysis finds that solar ponds are competitive when conventional heat sources are priced at $5 per million Btu and expected to rise in price at a rate of 10% per year. The application of solar ponds to the generation of electricity is also discussed. Total solar pond potential for displacing conventional energy sources is estimated in the range of from one to six quadrillion Btu per year in the near and intermediate future.

  16. Solar ponds

    SciTech Connect

    Jayadev, T.S.; Edesess, M.

    1980-04-01

    The different types of solar ponds are described, including the nonconvecting salt gradient pond and various saltless pond designs. Then the availability and cost of salts for salt gradient ponds are discussed and costs are compared. A simple computational model is developed to approximate solar pond performance. This model is later used to size solar ponds for district heating and industrial process heat applications. For district heating, ponds are sized to provide space conditioning for a group of homes, in different regions of the United States. Size requirement is on the order of one acre for a group of 25 to 50 homes. An economic analysis is performed of solar ponds used in two industrial process heat applications. The analysis finds that solar ponds are competitive when conventional heat sources are priced at $5 per million Btu and expected to rise in price at a rate of 10% per year. The application of solar ponds to the generation of electricity is also discussed. Total solar pond potential for displacing conventional energy sources is estimated in the range of from one to six quadrillion Btu per year in the near and intermediate future.

  17. Renewable energy technologies for federal facilities: Solar water heating

    SciTech Connect

    1996-05-01

    This sheet presents information on solar water heaters (passive and active), solar collectors (flat plate, evacuated tube, parabolic trough), lists opportunities for use of solar water heating, and describes what is required and the costs. Important terms are defined.

  18. [Passive smoking and respiratory health of children].

    PubMed

    Strumylaite, Loreta; Kregzdyte, Rima; Vaitkaitiene, Egle

    2005-01-01

    Passive smoking has been shown to be a risk factor for respiratory diseases in children. Some authors reported reduced lung function of children exposed to passive smoking. The purpose of the study was to assess the prevalence of exposure to passive smoking and its relation to respiratory health of Kaunas children. In 1998-2000 a cross-sectional survey was conducted in 20 kindergartens of Kaunas. Survey participants were 594 children (356 boys and 238 girls) aged 6-7 years. Children's parents filled out a questionnaire of the Swiss Study on Childhood Allergy and Respiratory Symptoms with Respect to Air Pollution designed on the basis of International Study of Asthma and Allergy in Childhood. Exposure to passive smoking was determined by an answer "everyday" or "sometimes" to the question "How often is your child in surrounding where someone smokes?". The parameters of respiratory function (FVC, FEV1, FEV1/FVC, FEF25, FEF50, FEF75, PEF) were measured with Pony Graphics 3.5. Response rate was 58.6% to 69.2% depending on a kindergarten. More than two fifth of children were exposed to passive smoking at home. Cough that lasted for at least four weeks during the past year was experienced by 24.5% and 16.9% of children with and without exposure to passive smoking (p<0.05). Wheezing in the past was found in 43% and 27% of children in groups compared (p<0.05). There was a significant difference in prevalence of sneezing or a runny/blocked nose when a child did not have a cold among children with and without exposure to passive smoking (46.6% and 36.6%, respectively, p<0.05). FEF25, FEF50, FEF75 and PEF of exposed girls were significantly lower than that of girls not exposed to passive smoking. Multiple regression analysis that included variables such as passive smoking, family history of allergy, smoked mother during pregnancy, gas stove and pets in child's room showed that FEF25 and FEF50 in girls were related to passive smoking. Our data show that more than two fifth of

  19. IV treatment at home

    MedlinePlus

    ... home; PICC line - home; Infusion therapy - home; Home health care - IV treatment ... Often, home health care nurses will come to your home to give you the medicine. Sometimes, a family member, a friend, or ...

  20. Solar Decathlon 2005

    SciTech Connect

    Warner, C.; Nahan, R.; King, R.

    2005-01-01

    Solar Decathlon 2005 is a U.S. Department of Energy and National Renewable Energy Laboratory competition involving 19 colleges and universities from the United States, Canada, and Spain. These teams will compete to design, build, and demonstrate solar homes. In fall 2005, teams will transport their competition solar houses to Washington, D.C., where they will construct a solar village on the National Mall. When the houses are assembled, the teams will compete against each other in 10 contests (hence, a decathlon) for about a week. The contests range from design to comfort to energy performance. Each team must provide an aesthetically pleasing entry that produces sufficient solar energy for space conditioning, hot water, lighting, appliances, and an electric car. The Solar Decathlon is co-sponsored by BP, The Home Depot, the American Institute of Architects, the National Association of Home Builders, and the DIY Network. For more information, visit the Web site at www.solardecathlon.org.

  1. Energy performance of net-zero and near net-zero energy homes in New England

    NASA Astrophysics Data System (ADS)

    Thomas, Walter D.

    Net-Zero Energy Homes (NZEHs) are homes that consume no more energy than they produce on site during the course of a year. They are well insulated and sealed, use energy efficient appliances, lighting, and mechanical equipment, are designed to maximize the benefits from day lighting, and most often use a combination of solar hot water, passive solar and photovoltaic (PV) panels to produce their on-site energy. To date, NZEHs make up a miniscule percentage of homes in the United States, and of those, few have had their actual performance measured and analyzed once built and occupied. This research focused on 19 NZEHs and near net-zero energy homes (NNZEHs) built in New England. This set of homes had varying designs, numbers of occupants, and installed technologies for energy production, space heating and cooling, and domestic hot water systems. The author worked with participating homeowners to collect construction and systems specifications, occupancy information, and twelve months of energy consumption, production and cost measurements, in order to determine whether the homes reached their respective energy performance design goals. The author found that six out of ten NZEHs achieved net-zero energy or better, while all nine of the NNZEHs achieved an energy density (kWh/ft 2/person) at least half as low as the control house, also built in New England. The median construction cost for the 19 homes was 155/ft 2 vs. 110/ft2 for the US average, their average monthly energy cost was 84% below the average for homes in New England, and their estimated CO2 emissions averaged 90% below estimated CO2 emissions from the control house. Measured energy consumption averaged 14% below predictions for the NZEHs and 38% above predictions for the NNZEHs, while generated energy was within +/- 10% of predicted for 17 out of 18 on-site PV systems. Based on these results, the author concludes that these types of homes can meet or exceed their designed energy performance (depending on

  2. Home Schooling.

    ERIC Educational Resources Information Center

    Gordon, William M.; And Others

    Cases that address the issue of home schooling are summarized in this report. Organized chronologically, each case description includes quoted material from the court ruling. Issues involve parent actions regarding compulsory student enrollment, parent qualifications for home teaching, student certification, church-state separation, constitutional…

  3. Energy considerations: Mobile homes in the south

    NASA Astrophysics Data System (ADS)

    Tilt, G. R.

    1981-11-01

    Mobile homes in the Southern region are discussed and their relationship to residential energy conservation is examined. Research being done in energy conservation and solar energy applications for manufactured houses is examined. A bibliography is included.

  4. Energy 101: Solar PV

    SciTech Connect

    2011-01-01

    Solar photovoltaic (PV) systems can generate clean, cost-effective power anywhere the sun shines. This video shows how a PV panel converts the energy of the sun into renewable electricity to power homes and businesses.

  5. Energy 101: Solar PV

    ScienceCinema

    None

    2016-07-12

    Solar photovoltaic (PV) systems can generate clean, cost-effective power anywhere the sun shines. This video shows how a PV panel converts the energy of the sun into renewable electricity to power homes and businesses.

  6. Heterojunction solar cell

    DOEpatents

    Olson, J.M.

    1994-08-30

    A high-efficiency single heterojunction solar cell is described wherein a thin emitter layer (preferably Ga[sub 0.52]In[sub 0.48]P) forms a heterojunction with a GaAs absorber layer. The conversion efficiency of the solar cell is at least 25.7%. The solar cell preferably includes a passivating layer between the substrate and the absorber layer. An anti-reflection coating is preferably disposed over the emitter layer. 1 fig.

  7. Heterojunction solar cell

    DOEpatents

    Olson, Jerry M.

    1994-01-01

    A high-efficiency single heterojunction solar cell wherein a thin emitter layer (preferably Ga.sub.0.52 In.sub.0.48 P) forms a heterojunction with a GaAs absorber layer. The conversion effiency of the solar cell is at least 25.7%. The solar cell preferably includes a passivating layer between the substrate and the absorber layer. An anti-reflection coating is preferably disposed over the emitter layer.

  8. Prescribing Activities that Engage Passive Residents. An Innovative Method

    PubMed Central

    Kolanowski, Ann; Buettner, Linda

    2009-01-01

    Individuals with dementia are often passive, which places them at risk for further cognitive and functional decline. Recreational activities have been used in research to reduce passive behaviors, but systematic reviews of these studies have found modest effect sizes for many activities. In this article, we describe the further theoretical development of an innovative method for prescribing activities that have a high likelihood of engaging nursing home residents who are passive and present examples for research application and clinical practice. This method may increase the effect size of activity interventions and encourage more widespread adoption of nonpharmacological interventions in practice. PMID:18274300

  9. [Diagnosis and treatment strategy of diseases due to passive smoking].

    PubMed

    Matsuzaki, Michiyuki

    2013-03-01

    Passive smoking causes a wide range of diseases from membrane irritation such as sore throat or nasal symptom, to fatal diseases such as lung cancer or heart attack. Extensive epidemiological studies have revealed that passive smoking at home or at workplaces raises the all cause mortality of nonsmoking family members by 14-75%. Moreover, many people in Japan are suffered from chemical hypersensitivity due to chronic persistent passive smoking at workplaces. Most critical diagnostic clue of passive smoking caused disease is the temporal relationship of tobacco smoke exposure and disease onset. One hundred percent smoke free workplace or environment is the only effective measure for curing and preventing illnesses caused by passive smoke exposure. PMID:23631237

  10. Home Modification

    MedlinePlus

    ... it is important to consider certain safety modifications. Adaptations such as those in the following list can ... The importance of a Consumer Perspective in Home Adaptation of Alzheimer’s Households” (Chapter 6 pp 91-112) ...

  11. Nursing Homes

    MedlinePlus

    ... up like a hospital. The staff provides medical care, as well as physical, speech and occupational therapy. ... relationships with residents. Some nursing homes have special care units for people with serious memory problems such ...

  12. Home Hemodialysis

    MedlinePlus

    ... more flexible schedule and better health. More Flexible Schedule A person can choose the schedule for home ... treat. When prepared, this content included the most current information available. For updates or for questions about ...

  13. Passive environmental temperature control system

    DOEpatents

    Corliss, John M.; Stickford, George H.

    1981-01-01

    Passive environmental heating and cooling systems are described, which utilize heat pipes to transmit heat to or from a thermal reservoir. In a solar heating system, a heat pipe is utilized to carry heat from a solar heat absorber plate that receives sunlight, through a thermal insulation barrier, to a heat storage wall, with the outer end of the pipe which is in contact with the solar absorber being lower than the inner end. The inclining of the heat pipe assures that the portion of working fluid, such as Freon, which is in a liquid phase will fall by gravity to the outer end of the pipe, thereby assuring diode action that prevents the reverse transfer of heat from the reservoir to the outside on cool nights. In a cooling system, the outer end of the pipe which connects to a heat dissipator, is higher than the inner end that is coupled to a cold reservoir, to allow heat transfer only out of the reservoir to the heat dissipator, and not in the reverse direction.

  14. Building America Top Innovations 2012: Zero Net-Energy Homes Production Builder Business Case: California/Florida Production Builders

    SciTech Connect

    none,

    2013-01-01

    This Building America Top Innovations profile describes Grupe Homes of Sacramento’s work with Building America to design California’s first production-scale community of solar homes. The homes outsold neighboring developments two to one.

  15. Passive magnetic bearing configurations

    DOEpatents

    Post, Richard F.

    2011-01-25

    A journal bearing provides vertical and radial stability to a rotor of a passive magnetic bearing system when the rotor is not rotating and when it is rotating. In the passive magnetic bearing system, the rotor has a vertical axis of rotation. Without the journal bearing, the rotor is vertically and radially unstable when stationary, and is vertically stable and radially unstable when rotating.

  16. Overcoming Passive Behavior.

    ERIC Educational Resources Information Center

    Kay, Marilyn

    1986-01-01

    Passivity in learning disabled children is identified as either inborn or as "learned helplessness," and the role of the teacher in overcoming passivity is noted. Teachers can help students understand themselves, become active agents in learning, and use self monitoring devices. (CL)

  17. Solar cell with back side contacts

    DOEpatents

    Nielson, Gregory N; Okandan, Murat; Cruz-Campa, Jose Luis; Resnick, Paul J; Wanlass, Mark Woodbury; Clews, Peggy J

    2013-12-24

    A III-V solar cell is described herein that includes all back side contacts. Additionally, the positive and negative electrical contacts contact compoud semiconductor layers of the solar cell other than the absorbing layer of the solar cell. That is, the positive and negative electrical contacts contact passivating layers of the solar cell.

  18. Home health care

    MedlinePlus

    ... Skilled nursing - home care; Physical therapy - at home; Occupational therapy - at home; Discharge - home health care ... medicines that you may be taking. Physical and occupational therapists can make sure your home is set ...

  19. The Medical Home

    MedlinePlus

    ... 5 Things to Know About Zika & Pregnancy The Medical Home KidsHealth > For Parents > The Medical Home Print ... home" for your child. What Does the Term "Medical Home" Mean? A medical home isn't a ...

  20. Report on Solar Water Heating Quantitative Survey

    SciTech Connect

    Focus Marketing Services

    1999-05-06

    This report details the results of a quantitative research study undertaken to better understand the marketplace for solar water-heating systems from the perspective of home builders, architects, and home buyers.

  1. Multiple uses of solar cookers

    SciTech Connect

    Shimeall, E.

    1992-12-31

    The author began using a solar cooker in 1980 and now uses it every day for six months of the year at her home in California. She describes using it for a variety of cooking activities including the canning of fruits and tomatoes. Energy savings in the home are said to be significant when compared to her neighbors due to use of the solar cooker, a solar water heater, and reduced need for air conditioning.

  2. Charge carrier trapping at passivated silicon surfaces

    NASA Astrophysics Data System (ADS)

    Seiffe, Johannes; Hofmann, Marc; Rentsch, Jochen; Preu, Ralf

    2011-03-01

    Surface passivation has become an essential factor for translating high-efficiency crystalline silicon solar cell concepts into industrial production schemes. In photovoltaics, a widespread method to determine the surface recombination is to measure the effective charge carrier lifetime from the photoconductance of symmetrically passivated silicon wafers in transient or quasi-static mode. In this work, it is shown how the injection history at the surface influences the transient effective lifetime measurement for several passivation layers. This dependence leads to systematic differences between quasi-static and transient measurements. The influence can be explained by charge trapping in slow surface states at the surface passivation layer. A model including slow surface states is used in a fit procedure to evaluate the capture cross sections of these traps. The observed effect is well-pronounced for silicon-rich passivation layers like a-Si:H, a-SiCx:H or silicon-rich a-SiOxNy:H. For PECVD-AlOx layers and for thermally grown SiO2 layers as well, however, the effective lifetime measurement could be influenced.

  3. Snails home

    NASA Astrophysics Data System (ADS)

    Dunstan, D. J.; Hodgson, D. J.

    2014-06-01

    Many gardeners and horticulturalists seek non-chemical methods to control populations of snails. It has frequently been reported that snails that are marked and removed from a garden are later found in the garden again. This phenomenon is often cited as evidence for a homing instinct. We report a systematic study of the snail population in a small suburban garden, in which large numbers of snails were marked and removed over a period of about 6 months. While many returned, inferring a homing instinct from this evidence requires statistical modelling. Monte Carlo techniques demonstrate that movements of snails are better explained by drift under the influence of a homing instinct than by random diffusion. Maximum likelihood techniques infer the existence of two groups of snails in the garden: members of a larger population that show little affinity to the garden itself, and core members of a local garden population that regularly return to their home if removed. The data are strongly suggestive of a homing instinct, but also reveal that snail-throwing can work as a pest management strategy.

  4. New Whole-House Solutions Case Study: Ravenwood Homes and Energy Smart Home Plans, Inc., Cape Coral, Florida

    SciTech Connect

    none,

    2012-10-01

    PNNL, Florida HERO, and Energy Smart Home Plans helped Ravenwood Homes achieve a HERS 15 with PV or HERS 65 without PV on a home in Florida with SEER 16 AC, concrete block and rigid foam walls, high-performance windows, solar water heating, and 5.98 kW PV.

  5. Home Insulation

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Under the Guaranteed Watt Savers (GWS) system, plans for a new home are computer analyzed for anticipated heat loss and gain. Specifications are specifically designed for each structure and a Smart- House Radiant Barrier is installed. Designed to reflect away 95% of the Sun's radiant energy, the radiant barrier is an adaptation of an aluminum shield used on Apollo spacecraft. On completion of a home, technicians using a machine, check for air tightness, by creating a vacuum in the house and computer calculations that measure the amount of air exchanged. A guarantee that only the specified number kilowatt hours will be used is then provided.

  6. Study on the effect of measuring methods on incident photon-to-electron conversion efficiency of dye-sensitized solar cells by home-made setup

    NASA Astrophysics Data System (ADS)

    Guo, Xiao-Zhi; Luo, Yan-Hong; Zhang, Yi-Duo; Huang, Xiao-Chun; Li, Dong-Mei; Meng, Qing-Bo

    2010-10-01

    An experimental setup is built for the measurement of monochromatic incident photon-to-electron conversion efficiency (IPCE) of solar cells. With this setup, three kinds of IPCE measuring methods as well as the convenient switching between them are achieved. The setup can also measure the response time and waveform of the short-circuit current of solar cell. Using this setup, IPCE results of dye-sensitized solar cells (DSCs) are determined and compared under different illumination conditions with each method. It is found that the IPCE values measured by AC method involving the lock-in technique are sincerely influenced by modulation frequency and bias illumination. Measurements of the response time and waveform of short-circuit current have revealed that this effect can be explained by the slow response of DSCs. To get accurate IPCE values by this method, the measurement should be carried out with a low modulation frequency and under bias illumination. The IPCE values measured by DC method under the bias light illumination will be disturbed since the short-circuit current increased with time continuously due to the temperature rise of DSC. Therefore, temperature control of DSC is considered necessary for IPCE measurement especially in DC method with bias light illumination. Additionally, high bias light intensity (>2 sun) is found to decrease the IPCE values due to the ion transport limitation of the electrolyte.

  7. (Solar greenhouse and barn collector)

    SciTech Connect

    Woodward, M.V.

    1981-08-04

    Use of a solar greenhouse and solar collectors to provide heat on a farm is briefly discussed. The greenhouse was used to heat the home, and the solar collectors provided hot water and heat for the barn. About $1500 was saved in oil bills from the previous year. (BCS)

  8. Nursing Home Checklist

    MedlinePlus

    Nursing home checklist Name of nursing home: ____________________________________________________ Address: ________________________________________________________________ Phone number: __________________________________________________________ Date of visit: _____________________________________________________________ Basic information Yes No Notes Is the nursing home Medicare certified? Is the nursing ...

  9. Subsystem design package for Solar II collector

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The requirements for the design and performance of the Solar 2 Collector Subsystem developed for use in solar heating of single family residences and mobile homes are presented. Installation drawings are included.

  10. Home Economics.

    ERIC Educational Resources Information Center

    Ontario Dept. of Education, Toronto. School Planning and Building Research Section.

    This presentation of suggested layouts and specifications for home economics facilities has been prepared to be of service to school boards, architects, teachers, and administrators who are planning new schools or making renovations to existing structures. Room layouts are shown for a foods and nutrition room, or the foods and nutrition area of a…

  11. Home Modifications

    MedlinePlus

    ... use, and flexible enough to be adapted for special needs. Back to top Evaluating Your Needs Before any changes are made to the home, evaluate your current and future needs room by room. Once you have explored all areas, make a list of potential problems and solutions. ...

  12. Regional variation in solar energy economic performance

    NASA Astrophysics Data System (ADS)

    Brunton, D.; Kirschner, C.; Ben-David, S.; Roach, F.

    1981-03-01

    A solar economic performance code (EASE-III) was used to indicate the extent of production function variations as applied to a Trombe wall solar design incorporated in a new home. The economic performance of the solar heated residence was compared to the alternative non solar home heated by the characteristic conventional fuel of each region. These economic results are used to discuss the impact of subsidy programs.

  13. Progress in solar engineering

    SciTech Connect

    Yogi Goswami, D.

    1987-01-01

    This book presents reviews of various areas of solar energy technology, including wind energy technology and ocean thermal energy conversion (OTEC). It also identifies and suggests needs and future directions of research and development. The subjects covered in this book include solar thermal power technology, solar thermal storage, solar ponds, industrial process heat, solar water heating, active and passive solar cooling methods, low-cost collector development, photovoltaic research and applications, wind energy technology, and OTEC. Also covered are the status of the technology, basic and applied research, design and analysis methods, and performance and operational experiences of various systems. The book will thus be helpful as a review of various solar, wind, and OTEC technologies.

  14. Manual for solar specialists

    SciTech Connect

    Not Available

    1982-07-01

    The objective of the manual is to meet the specific training needs of code enforcement personnel in connection with the examination of plans for and the inspection of solar energy installations. There is a brief historical review and discussion of geographical dependence of solar feasibility. The fundamentals of solar energy are presented to establish the quantity of solar energy which can be anticipated in a particular geographic location. The active, passive, and hybrid solar systems are described, telling how insolation is collected, stored, and distributed by various means. The physical and theoretical components of solar systems are related to specific code enforcement techniques. Also, the recommended requirements to code officials for solar heating, cooling, and hot water systems are reviewed and discussed. (LEW)

  15. Home Seismometer

    NASA Astrophysics Data System (ADS)

    Horiuchi, S.; Yamamoto, S.; Nakmaura, H.; Wu, C.; Rydelek, P.; Kachi, M.

    2007-12-01

    We have developed an automated system for analyzing Hi-net seismograms for earthquake early warning (EEW) in Japan. Because of limitations imposed by station spacing, our system generally cannot issue an EEW to areas within about 30 km distance of the earthquake's hypocenter. We estimate that about 10 times the number of stations would be needed to issue an EEW in these areas, but the overhead would be cost prohibitive for governmental agencies. The practical deployment of EEW in Japan has started in October, 2007 and millions of people are expected to purchase and install the receiving/alarm unit of EEW. Since most of these units are connected to internet and equipped with a CPU and memory, we realized that the addition of an inexpensive seismometer and digitizer would transform the receiver into a real-time seismic observatory, which we are calling a home seismometer; these modifications only cost about $20. The home seismometer can help to generate alerts at the time of the occurrence of a large local earthquake by using locally observed data. Also, home seismograms can be used to estimate the amplification factor in sedimentary layers, which will be used to determine the site correction for shaking intensity by comparing the waveform data from the home seismometer against those from nearby Hi-net or K-NET stations. This amplification factor, which is essentially the basis of a shake-map with very-high spatial resolution, will help to establish a safety index of houses/buildings for large earthquakes, since a structure located at a site with large seismic amplification can be damaged more seriously than those with small amplification factors. The installation of home seismometers will create an extremely dense seismic network that is without precedence. We are developing an automatic system that collects waveform data from all home seismometer installations, calculates earthquake parameters in real-time, and then sends back alarms signals based on computed

  16. Home Health Care

    MedlinePlus

    ... Page Resize Text Printer Friendly Online Chat Home Health Care Home health care helps older adults live independently for as long ... need for long-term nursing home care. Home health care may include occupational and physical therapy, speech therapy, ...

  17. How Solar Energy Can Work for You

    ERIC Educational Resources Information Center

    Iker, Sam

    1978-01-01

    The future of solar heated homes looks bright. The increase in availability of solar hardware and information along with tax credits point to an increase in both solar water and space heating. Solar systems can add to the value of a house. (BB)

  18. [Home Treatment].

    PubMed

    Widmann, F; Bachhuber, G; Riedelsheimer, A; Schiele, A; Ullrich, S; Kilian, R; Becker, T; Frasch, K

    2016-01-01

    Home Treatment (HT) means acute psychiatric treatment in the patient's usual environment. Conceptually, HT is to be differentiated from other home-based services: It is limited with regard to duration and multiprofessional (e. g. psychiatrist plus psychiatric nursing staff plus social worker); the "24/7"-accessibility is frequently provided by the corresponding background hospital infrastructure. Target group are acutely mentally ill persons with an indication to inpatient treatment, who are willing to cooperate, and absence of endangerment to self and others. In contrast to the Scandinavian and many Anglophone countries where nationwide HT services are delivered, there are not many HT sites in Germany so far. Consequently, empirical data concerning HT in Germany is scarce. In summary, international studies show equivalent effects on psychopathological measures compared to inpatient treatment, reductions with regard to inpatient days, higher patient satisfaction and a trend towards cost-effectivity. PMID:26878432

  19. Design and Performance of the Van Geet Off-Grid Home: Preprint

    SciTech Connect

    Barley, C. D.; Torcellini, P.; Van Geet, O.

    2003-01-01

    The Van Geet home near Denver, Colorado, demonstrates the successful integration of energy conservation measures and renewable energy supply in a beautiful, comfortable, energy-efficient, 295-m2 (3,176-ft2) off-grid home in a cold, sunny climate. Features include a tight envelope, energy-efficient appliances, passive solar heating (direct gain and Trombe wall), natural cooling, solar hot water, and photovoltaics. In addition to describing this house and its performance, this paper describes the recommended design process of (1) setting a goal for energy efficiency at the outset, (2) applying rules of thumb, and (3) using computer simulation to fine-tune the design. Performance monitoring and computer simulation are combined for the best possible analysis of energy performance. In this case, energy savings are estimated as 89% heating and cooling, 83% electrical, and nearly 100% domestic water heating. The heating and cooling energy use is 8.96 kJ/Cdaym2 (0.44 Btu/Fdayft2).

  20. Home Energy Score

    SciTech Connect

    2011-12-16

    The Home Energy Score allows a homeowner to compare her or his home's energy consumption to that of other homes, similar to a vehicle's mile-per-gallon rating. A home energy assessor will collect energy information during a brief home walk-through and then score that home on a scale of 1 to 10.

  1. Solar Energy Research Institute Validation Test House Site Handbook

    SciTech Connect

    Burch, J.; Wortman, D.; Judkoff, R.; Hunn, B.

    1985-05-01

    The Validation Test House at the Solar Energy Research Institute in Golden, Colorado, is being used to collect performance data for analysis/design tool validation as part of the DOE Passive Solar Class A Performance Evaluation Program.

  2. Method for processing silicon solar cells

    DOEpatents

    Tsuo, Y.S.; Landry, M.D.; Pitts, J.R.

    1997-05-06

    The instant invention teaches a novel method for fabricating silicon solar cells utilizing concentrated solar radiation. The solar radiation is concentrated by use of a solar furnace which is used to form a front surface junction and back-surface field in one processing step. The present invention also provides a method of making multicrystalline silicon from amorphous silicon. The invention also teaches a method of texturing the surface of a wafer by forming a porous silicon layer on the surface of a silicon substrate and a method of gettering impurities. Also contemplated by the invention are methods of surface passivation, forming novel solar cell structures, and hydrogen passivation. 2 figs.

  3. Method for processing silicon solar cells

    DOEpatents

    Tsuo, Y. Simon; Landry, Marc D.; Pitts, John R.

    1997-01-01

    The instant invention teaches a novel method for fabricating silicon solar cells utilizing concentrated solar radiation. The solar radiation is concentrated by use of a solar furnace which is used to form a front surface junction and back-surface field in one processing step. The present invention also provides a method of making multicrystallline silicon from amorphous silicon. The invention also teaches a method of texturing the surface of a wafer by forming a porous silicon layer on the surface of a silicon substrate and a method of gettering impurities. Also contemplated by the invention are methods of surface passivation, forming novel solar cell structures, and hydrogen passivation.

  4. Wireless passive radiation sensor

    SciTech Connect

    Pfeifer, Kent B; Rumpf, Arthur N; Yelton, William G; Limmer, Steven J

    2013-12-03

    A novel measurement technique is employed using surface acoustic wave (SAW) devices, passive RF, and radiation-sensitive films to provide a wireless passive radiation sensor that requires no batteries, outside wiring, or regular maintenance. The sensor is small (<1 cm.sup.2), physically robust, and will operate unattended for decades. In addition, the sensor can be insensitive to measurement position and read distance due to a novel self-referencing technique eliminating the need to measure absolute responses that are dependent on RF transmitter location and power.

  5. Photojournal Home Page Graphic 2007

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This image is an unannotated version of the Photojournal Home Page graphic released in October 2007. This digital collage contains a highly stylized rendition of our solar system and points beyond. As this graphic was intended to be used as a navigation aid in searching for data within the Photojournal, certain artistic embellishments have been added (color, location, etc.). Several data sets from various planetary and astronomy missions were combined to create this image.

  6. Planetary Photojournal Home Page Graphic

    NASA Technical Reports Server (NTRS)

    2004-01-01

    This image is an unannotated version of the Planetary Photojournal Home Page graphic. This digital collage contains a highly stylized rendition of our solar system and points beyond. As this graphic was intended to be used as a navigation aid in searching for data within the Photojournal, certain artistic embellishments have been added (color, location, etc.). Several data sets from various planetary and astronomy missions were combined to create this image.

  7. DOE Zero Energy Ready Home Case Study: TC Legend Homes, Seattle, Washington

    SciTech Connect

    none,

    2013-09-01

    This house incorporates slab-on-grade, EPS roof, and radiant heating with an air-to-water heat pump that also preheats domestic hot water. Without counting in the solar panels, the home earns a home energy rating system (HERS) score of 37, with projected utility bills of about $740 a year. With the 6.4-kW photovoltaic power system installed on the roof, the home’s HERS scores drops to -1 and utility bills for the all-electric home drop to zero. This home was awarded a 2013 Housing Innovation Award in the affordable builder category.

  8. Method of passivating semiconductor surfaces

    DOEpatents

    Wanlass, Mark W.

    1990-01-01

    A method of passivating Group III-V or II-VI semiconductor compound surfaces. The method includes selecting a passivating material having a lattice constant substantially mismatched to the lattice constant of the semiconductor compound. The passivating material is then grown as an ultrathin layer of passivating material on the surface of the Group III-V or II-VI semiconductor compound. The passivating material is grown to a thickness sufficient to maintain a coherent interface between the ultrathin passivating material and the semiconductor compound. In addition, a device formed from such method is also disclosed.

  9. Method of passivating semiconductor surfaces

    DOEpatents

    Wanlass, M.W.

    1990-06-19

    A method is described for passivating Group III-V or II-VI semiconductor compound surfaces. The method includes selecting a passivating material having a lattice constant substantially mismatched to the lattice constant of the semiconductor compound. The passivating material is then grown as an ultrathin layer of passivating material on the surface of the Group III-V or II-VI semiconductor compound. The passivating material is grown to a thickness sufficient to maintain a coherent interface between the ultrathin passivating material and the semiconductor compound. In addition, a device formed from such method is also disclosed.

  10. Solar Glazing Tips for School Construction

    ERIC Educational Resources Information Center

    Smith, Jonathan

    2012-01-01

    Glazing can be optimized to enhance passive solar heating and daylight harvesting by exceeding the prescriptive limits of the energy code. This savings can be garnered without the high cost of external overhangs or expensive glazing products. The majority of savings from solar glazing are attributable to the increase in solar heating and…

  11. Anti-reverse siphon solar heating system

    SciTech Connect

    Larkin, W. J.

    1985-05-28

    A solar heater which is adapted for liquid heating and space heating, or both, utilizes a passive anti-reverse siphon concept in which fresh air or water is required to traverse upwardly along a passageway and then descend along a descending passageway insulated from the ascending passageway before it enters the solar heating chamber, with the result that the pressure heads generated in the ascending and descending passageways and the heating chamber offset one another such that forward, passive solar heating convection occurs, but in the evening when the heating chamber becomes cool, the normal reverse convection that occurs in passive units is stopped.

  12. Characterization of laser transferred contact through aluminum oxide passivation layer

    NASA Astrophysics Data System (ADS)

    Urabe, Shunsuke; Irikawa, Junpei; Konagai, Makoto; Miyajima, Shinsuke

    2015-08-01

    The point contact structure of the rear side of crystalline silicon solar cells is used to realize high passivation quality and good electrical contact. A conversion efficiency of 19.8% was achieved on the passivated emitter and rear cell (PERC) structure with a widegap heterojunction emitter. In this solar cell, laser-fired contact (LFC) process is used to make the point contacts. In the LFC process, laser irradiation damage to the surface of crystalline silicon was found to be the big issues for higher passivation quality. We investigated laser-transferred contact (LTC) process as a new contacts formation process. The LTC samples showed higher effective minority carrier lifetime and good contact resistivity compared with the LFC samples.

  13. Solar heated beehives

    SciTech Connect

    Hardin, B.

    1985-02-01

    A new translucent plastic cover for bee hives is described which will serve as a passive solar collector and insulator. Scientists at the USDA-ARS designed the cover to maintain bees in cold weather. It should be of interest to beekeepers in northern states who have had to destroy colonies to avoid overwintering costs.

  14. Solar Energy Now.

    ERIC Educational Resources Information Center

    Rose, Harvey, Ed.

    Twenty articles addressing different aspects of solar energy are compiled in this book. They represent the views of different governmental and non-governmental organizations, members of congress, and other individuals including, for example, Barry Commoner and Amory Lovins. Topics discussed include the need for federal support, passive solar…

  15. Thermal performance of evacuated tube heat pipe solar collector

    NASA Astrophysics Data System (ADS)

    Putra, Nandy; Kristian, M. R.; David, R.; Haliansyah, K.; Ariantara, Bambang

    2016-06-01

    The high fossil energy consumption not only causes the scarcity of energy but also raises problems of global warming. Increasing needs of fossil fuel could be reduced through the utilization of solar energy by using solar collectors. Indonesia has the abundant potential for solar energy, but non-renewable energy sources still dominate energy consumption. With heat pipe as passive heat transfer device, evacuated tube solar collector is expected to heat up water for industrial and home usage without external power supply needed to circulate water inside the solar collector. This research was conducted to determine the performance of heat pipe-based evacuated tube solar collector as solar water heater experimentally. The experiments were carried out using stainless steel screen mesh as a wick material, and water and Al2O3-water 0.1% nanofluid as working fluid, and applying inclination angles of 0°, 15°, 30°, and 45°. To analyze the heat absorbed and transferred by the prototype, water at 30°C was circulated through the condenser. A 150 Watt halogen lamp was used as sun simulator, and the prototype was covered by an insulation box to obtain a steady state condition with a minimum affection of ambient changes. Experimental results show that the usage of Al2O3-water 0.1% nanofluid at 30° inclination angle provides the highest thermal performance, which gives efficiency as high as 0.196 and thermal resistance as low as 5.32 °C/W. The use of nanofluid as working fluid enhances thermal performance due to high thermal conductivity of the working fluid. The increase of the inclination angle plays a role in the drainage of the condensate to the evaporator that leads to higher thermal performance until the optimal inclination angle is reached.

  16. Hybrid passivated colloidal quantum dot solids

    NASA Astrophysics Data System (ADS)

    Ip, Alexander H.; Thon, Susanna M.; Hoogland, Sjoerd; Voznyy, Oleksandr; Zhitomirsky, David; Debnath, Ratan; Levina, Larissa; Rollny, Lisa R.; Carey, Graham H.; Fischer, Armin; Kemp, Kyle W.; Kramer, Illan J.; Ning, Zhijun; Labelle, André J.; Chou, Kang Wei; Amassian, Aram; Sargent, Edward H.

    2012-09-01

    Colloidal quantum dot (CQD) films allow large-area solution processing and bandgap tuning through the quantum size effect. However, the high ratio of surface area to volume makes CQD films prone to high trap state densities if surfaces are imperfectly passivated, promoting recombination of charge carriers that is detrimental to device performance. Recent advances have replaced the long insulating ligands that enable colloidal stability following synthesis with shorter organic linkers or halide anions, leading to improved passivation and higher packing densities. Although this substitution has been performed using solid-state ligand exchange, a solution-based approach is preferable because it enables increased control over the balance of charges on the surface of the quantum dot, which is essential for eliminating midgap trap states. Furthermore, the solution-based approach leverages recent progress in metal:chalcogen chemistry in the liquid phase. Here, we quantify the density of midgap trap states in CQD solids and show that the performance of CQD-based photovoltaics is now limited by electron-hole recombination due to these states. Next, using density functional theory and optoelectronic device modelling, we show that to improve this performance it is essential to bind a suitable ligand to each potential trap site on the surface of the quantum dot. We then develop a robust hybrid passivation scheme that involves introducing halide anions during the end stages of the synthesis process, which can passivate trap sites that are inaccessible to much larger organic ligands. An organic crosslinking strategy is then used to form the film. Finally, we use our hybrid passivated CQD solid to fabricate a solar cell with a certified efficiency of 7.0%, which is a record for a CQD photovoltaic device.

  17. Hybrid passivated colloidal quantum dot solids.

    PubMed

    Ip, Alexander H; Thon, Susanna M; Hoogland, Sjoerd; Voznyy, Oleksandr; Zhitomirsky, David; Debnath, Ratan; Levina, Larissa; Rollny, Lisa R; Carey, Graham H; Fischer, Armin; Kemp, Kyle W; Kramer, Illan J; Ning, Zhijun; Labelle, André J; Chou, Kang Wei; Amassian, Aram; Sargent, Edward H

    2012-09-01

    Colloidal quantum dot (CQD) films allow large-area solution processing and bandgap tuning through the quantum size effect. However, the high ratio of surface area to volume makes CQD films prone to high trap state densities if surfaces are imperfectly passivated, promoting recombination of charge carriers that is detrimental to device performance. Recent advances have replaced the long insulating ligands that enable colloidal stability following synthesis with shorter organic linkers or halide anions, leading to improved passivation and higher packing densities. Although this substitution has been performed using solid-state ligand exchange, a solution-based approach is preferable because it enables increased control over the balance of charges on the surface of the quantum dot, which is essential for eliminating midgap trap states. Furthermore, the solution-based approach leverages recent progress in metal:chalcogen chemistry in the liquid phase. Here, we quantify the density of midgap trap states in CQD solids and show that the performance of CQD-based photovoltaics is now limited by electron-hole recombination due to these states. Next, using density functional theory and optoelectronic device modelling, we show that to improve this performance it is essential to bind a suitable ligand to each potential trap site on the surface of the quantum dot. We then develop a robust hybrid passivation scheme that involves introducing halide anions during the end stages of the synthesis process, which can passivate trap sites that are inaccessible to much larger organic ligands. An organic crosslinking strategy is then used to form the film. Finally, we use our hybrid passivated CQD solid to fabricate a solar cell with a certified efficiency of 7.0%, which is a record for a CQD photovoltaic device.

  18. Solar ponds. Citations from the NTIS data base

    NASA Astrophysics Data System (ADS)

    Hundemann, A. S.

    1980-08-01

    Federally funded research on the design, performance, and use of solar ponds is discussed on these. Topic areas cover the use of solar ponds in industrial process heat production, roof ponds for passive solar buildings, and solar ponds use in the production of biomass for renewable fuels.

  19. Passivated niobium cavities

    SciTech Connect

    Myneni, Ganapati Rao; Hjorvarsson, Bjorgvin; Ciovati, Gianluigi

    2006-12-19

    A niobium cavity exhibiting high quality factors at high gradients is provided by treating a niobium cavity through a process comprising: 1) removing surface oxides by plasma etching or a similar process; 2) removing hydrogen or other gases absorbed in the bulk niobium by high temperature treatment of the cavity under ultra high vacuum to achieve hydrogen outgassing; and 3) assuring the long term chemical stability of the niobium cavity by applying a passivating layer of a superconducting material having a superconducting transition temperature higher than niobium thereby reducing losses from electron (cooper pair) scattering in the near surface region of the interior of the niobium cavity. According to a preferred embodiment, the passivating layer comprises niobium nitride (NbN) applied by reactive sputtering.

  20. Passive broadband acoustic thermometry

    NASA Astrophysics Data System (ADS)

    Anosov, A. A.; Belyaev, R. V.; Klin'shov, V. V.; Mansfel'd, A. D.; Subochev, P. V.

    2016-04-01

    The 1D internal (core) temperature profiles for the model object (plasticine) and the human hand are reconstructed using the passive acoustothermometric broadband probing data. Thermal acoustic radiation is detected by a broadband (0.8-3.5 MHz) acoustic radiometer. The temperature distribution is reconstructed using a priori information corresponding to the experimental conditions. The temperature distribution for the heated model object is assumed to be monotonic. For the hand, we assume that the temperature distribution satisfies the heat-conduction equation taking into account the blood flow. The average error of reconstruction determined for plasticine from the results of independent temperature measurements is 0.6 K for a measuring time of 25 s. The reconstructed value of the core temperature of the hand (36°C) generally corresponds to physiological data. The obtained results make it possible to use passive broadband acoustic probing for measuring the core temperatures in medical procedures associated with heating of human organism tissues.

  1. Passive fetal monitoring sensor

    NASA Technical Reports Server (NTRS)

    Zuckerwar, Allan J. (Inventor); Hall, Earl T. (Inventor); Baker, Donald A. (Inventor); Bryant, Timothy D. (Inventor)

    1992-01-01

    An ambulatory, passive sensor for use in a fetal monitoring system is discussed. The invention is comprised of a piezoelectric polymer film, combined with a metallic mounting plate fastened to a belt, and electrically connected to a signal processing unit by means of a shielded cable. The purpose of the sensor is to receive pressure pulses emitted by a fetus inside an expectant mother. Additionally, the monitor will filter out pressure pulses arising from other sources, such as the maternal heart.

  2. Passively actuated valve

    DOEpatents

    Modro, S. Michael; Ougouag, Abderrafi M.

    2005-09-20

    A passively actuated valve for isolating a high pressure zone from a low pressure zone and discontinuing the isolation when the pressure in the high pressure zone drops below a preset threshold. If the pressure in the high pressure zone drops below the preset threshold, the valve opens and allows flow from the high pressure zone to the low pressure zone. The valve remains open allowing pressure equalization and back-flow should a pressure inversion between the two pressure zone occur.

  3. Respiratory Home Health Care

    MedlinePlus

    ... Healthy Living > Living With Lung Disease > Respiratory Home Health Care Font: Aerosol Delivery Oxygen Resources Immunizations Pollution Nutrition ... Disease Articles written by Respiratory Experts Respiratory Home Health Care Respiratory care at home can contribute to improved ...

  4. Staying safe at home

    MedlinePlus

    Carbon monoxide safety; Electrical safety; Furnace safety; Gas appliance safety; Water heater safety ... inside the home and outside the home: Put gas and charcoal grills well away from your home, ...

  5. Home Care Services

    MedlinePlus

    Home care is care that allows a person with special needs stay in their home. It might be for people who are getting ... chronically ill, recovering from surgery, or disabled. Home care services include Personal care, such as help with ...

  6. Genetics Home Reference

    MedlinePlus

    Skip Navigation Bar Home Current Issue Past Issues Genetics Home Reference Past Issues / Spring 2007 Table of ... of this page please turn Javascript on. The Genetics Home Reference (GHR) Web site — ghr.nlm.nih. ...

  7. Exercise at Home

    MedlinePlus

    ... Divisions Home Health Insights Exercise Exercise at Home Exercise at Home Make an Appointment Ask a Question ... with the movement and contact your provider. Posture Exercises Better posture means better breathing and movement. Axial ...

  8. Solar Decathlon 2005: The Event in Review

    SciTech Connect

    Moon, S.; Nahan, R.; Warner, C.; Wassmer, M.

    2006-06-01

    Solar Decathlon 2005: The Event in Review is a technical report describing the 2005 Solar Decathlon, an event sponsored by the U.S. Department of Energy wherein 18 collegiate teams competed in 10 contests to design, build, and operate an attractive, efficient, entirely solar-powered home. The report gives an overview of the competition, including final results, team strategies, and detailed descriptions the 18 homes.

  9. 22. 8% efficient silicon solar cell

    SciTech Connect

    Blakers, A.W.; Wang, A.; Milne, A.M.; Zhao, J.; Green, M.A. )

    1989-09-25

    A new silicon solar cell structure, the passivated emitter and rear cell, is described. The cell structure has yielded independently confirmed efficiencies of up to 22.8%, the highest ever reported for a silicon cell.

  10. Incremental cooling load determination for passive direct gain heating systems

    NASA Astrophysics Data System (ADS)

    Sullivan, P. W.; Mahone, D.; Fuller, W.; Gruber, J.; Kammerud, R.; Place, W.; Anderson, B.

    1981-05-01

    The applicability of the National Association of Home Builders (NAHB) full load compressor hour method for predicting the cooling load increase in a residence attributable to direct gain passive heating systems is examined. The NAHB method predictions are compared with the results of 200 hour-by-hour simulations using BLAST, and the two methods show reasonable agreement. The degree of agreement and the limitations of the NAHB method are discussed.

  11. Passivation effects on quantum dots prepared by successive ionic layer adsorption and reaction.

    PubMed

    Dai, Qilin; Maloney, Scott; Chen, Weimin; Poudyal, Uma; Wang, Wenyong

    2016-06-01

    ZnS is typically used to passivate semiconductor quantum dots (QDs) prepared by the successive ionic layer adsorption and reaction (SILAR) method for solar cell applications, while for colloidal QDs, organic ligands are usually used for this passivation purpose. In this study we utilized oleylamine and oleic acid ligands, besides ZnS, to passivate QDs prepared by the SILAR approach, and investigated their effects on the incident photon-to-current efficiency (IPCE) performance of the solar cells. It was observed that oleylamine passivation decreased device performance, while oleic acid passivation improved the IPCE of the cells. Redshift of the IPCE onset wavelength was also observed after oleic acid coating, which was attributed to the delocalization of excitons in the CdS QDs. PMID:27103144

  12. High Performance Builder Spotlight: Wathen Castanos Hybrid Homes

    SciTech Connect

    2011-01-01

    Wathen Castanos Hybrid Homes of Fresno, CA, has worked with Building America team member IBACOS to apply building science to production homes. Even without solar panels, the company’s Jordan model exceeds California’s building efficiency standard by 36%.

  13. Builders Challenge High Performance Builder Spotlight - Artistic Homes, Albuquerque, NM

    SciTech Connect

    2009-01-01

    Building America Builders Challenge fact sheet on Artistic Homes of Albuquerque, New Mexico. Describes the first true zero E-scale home in a hot-dry climate with ducts inside, R-50 attic insulation, roof-mounted photovoltaic power system, and solar thermal water heating.

  14. Role of passive remote sensors. Sensor System Panel report

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Capabilities of present passive systems are described and the development of passive remote sensing systems for the more abundant tropospheric trace species is recommended. The combination of nadir-viewing spectrometers and solar occultation for tropospheric measurement of those gases having large stratospheric burdens is discussed. Development of a nadir-viewing instrument capable of obtaining continuous spectra in narrower bands is recommended. Gas filter radiometers for species specific measurements and development of a spectral survey instrument are discussed. Further development of aerosol retrieval algorithms, including polarization techniques, for obtaining aerosol thickness and size distributions is advised. Recommendations of specific investigations to be pursued are presented.

  15. Passive Microwave Remote Sensing of Soil Moisture

    NASA Technical Reports Server (NTRS)

    Njoku, Eni G.; Entekhabi, Dara

    1996-01-01

    Microwave remote sensing provides a unique capability for direct observation of soil moisture. Remote measurements from space afford the possibility of obtaining frequent, global sampling of soil moisture over a large fraction of the Earth's land surface. Microwave measurements have the benefit of being largely unaffected by cloud cover and variable surface solar illumination, but accurate soil moisture estimates are limited to regions that have either bare soil or low to moderate amounts of vegetation cover. A particular advantage of passive microwave sensors is that in the absence of significant vegetation cover soil moisture is the dominant effect on the received signal. The spatial resolutions of passive Microwave soil moisture sensors currently considered for space operation are in the range 10-20 km. The most useful frequency range for soil moisture sensing is 1-5 GHz. System design considerations include optimum choice of frequencies, polarizations, and scanning configurations, based on trade-offs between requirements for high vegetation penetration capability, freedom from electromagnetic interference, manageable antenna size and complexity, and the requirement that a sufficient number of information channels be available to correct for perturbing geophysical effects. This paper outlines the basic principles of the passive microwave technique for soil moisture sensing, and reviews briefly the status of current retrieval methods. Particularly promising are methods for optimally assimilating passive microwave data into hydrologic models. Further studies are needed to investigate the effects on microwave observations of within-footprint spatial heterogeneity of vegetation cover and subsurface soil characteristics, and to assess the limitations imposed by heterogeneity on the retrievability of large-scale soil moisture information from remote observations.

  16. Fundamental studies of passivity and passivity breakdown. Final report

    SciTech Connect

    Macdonald, D.D.; Urquidi-Macdonald, M.; Song, H.; Biaggio-Rocha, S.; Searson, P.

    1991-11-01

    This report summarizes the findings of our fundamental research program on passivity and passivity breakdown. During the past three and one half years in this program (including the three year incrementally-funded grant prior to the present grant), we developed and experimentally tested various physical models for the growth and breakdown of passive films on metal surfaces. These models belong to a general class termed ``point defects models`` (PDMs), in which the growth and breakdown of passive films are described in terms of the movement of anion and cation vacancies.

  17. Energy 101: Concentrating Solar Power

    ScienceCinema

    None

    2016-07-12

    From towers to dishes to linear mirrors to troughs, concentrating solar power (CSP) technologies reflect and collect solar heat to generate electricity. A single CSP plant can generate enough power for about 90,000 homes. This video explains what CSP is, how it works, and how systems like parabolic troughs produce renewable power. For more information on the Office of Energy Efficiency and Renewable Energy's CSP research, see the Solar Energy Technology Program's Concentrating Solar Power Web page at http://www1.eere.energy.gov/solar/csp_program.html.

  18. Energy 101: Concentrating Solar Power

    SciTech Connect

    2010-01-01

    From towers to dishes to linear mirrors to troughs, concentrating solar power (CSP) technologies reflect and collect solar heat to generate electricity. A single CSP plant can generate enough power for about 90,000 homes. This video explains what CSP is, how it works, and how systems like parabolic troughs produce renewable power. For more information on the Office of Energy Efficiency and Renewable Energy's CSP research, see the Solar Energy Technology Program's Concentrating Solar Power Web page at http://www1.eere.energy.gov/solar/csp_program.html.

  19. DOE Zero Energy Ready Home Case Study: The Imery Group — Proud Green Home, Serenbe, GA

    SciTech Connect

    none,

    2014-09-01

    The first certified Zero Energy Ready Home in Georgia was honored in the Custom Builder category of the 2014 Housing Innovation Awards. The 2,811-ft2, two-story custom home has 2x6 advanced framed walls filled with R-20 of open-cell spray foam, plus an R-6.6 insulated coated OSB sheathing. Also included is electronic monitoring equipment that tracks the PV, solar thermal water heater, ERV, mini-split heat pump with three indoor heads, solar water heater, and LED and CFL lighting.

  20. Passive immunization of pigeons against trichomoniasis

    USGS Publications Warehouse

    Kocan, R.M.

    1970-01-01

    Nonimmune homing pigeons Columba livia were infected with the Jones' Barn strain of Trichomonas gallinae and subsequently transfused with plasma from acute or chronically infected pigeons harboring one of 3 different strains of T. gallinae. The transfusions were either a single 2 mi dose given one day after inoculation or three 1 ml doses given 0, 5, and 10 days after inoculation. Plasma from pigeons harboring any of the 3 strains was capable of passively immunizing nonimmune birds. All birds which were immunized with plasma from infected pigeons survived until killed at the end of the test period and no visceral lesions were found on necropsy but trichomonads were present in the oropharynx. All controls (untreated or transfused with normal plasma) died of visceral trichomoniasis. Immune plasma produced some lysis of trichomonads in vitro, and inhibition of motility and vacuolization occurred in some of the non-lysed organisms. The overall lytic activity in vitro affected less than 10% of the suspended trichomonads.

  1. Passive bistatic radar analysis

    NASA Astrophysics Data System (ADS)

    O'Hagan, Daniel W.; Kuschel, H.; Schiller, Joachim

    2009-06-01

    Passive Bistatic Radar (PBR) research is at its zenith with several notable PBR systems currently operational, or available for deployment. Such PBRs include the Manastash Ridge Radar (MRR) developed for and by academia; Silent Sentry developed as a commercial concern by Lockheed Martin; and Homeland Alerter (HA100) also a commercial system developed by Thales. However at present, despite the existence of numerous PBR prototypes, take up of commercial passive radar technology remains slow. This is due in part to technology immaturity, in part to politics, and particularly due to the fact that monostatic radars perform so well. If PBRs are to enjoy longevity as a viable technology then it is imperative that they address certain niche application areas, with the aforementioned MRR being one prime example of this. The focus of this paper will be an analysis of a PBR system that utilised FM radio signals of opportunity to detect aircraft targets with an RCS generally not lower than 20 m2. The paper will demonstrate the theoretical detection coverage of an FM based PBR operating in a severe interference environment.

  2. Fly ash carbon passivation

    DOEpatents

    La Count, Robert B; Baltrus, John P; Kern, Douglas G

    2013-05-14

    A thermal method to passivate the carbon and/or other components in fly ash significantly decreases adsorption. The passivated carbon remains in the fly ash. Heating the fly ash to about 500 and 800 degrees C. under inert gas conditions sharply decreases the amount of surfactant adsorbed by the fly ash recovered after thermal treatment despite the fact that the carbon content remains in the fly ash. Using oxygen and inert gas mixtures, the present invention shows that a thermal treatment to about 500 degrees C. also sharply decreases the surfactant adsorption of the recovered fly ash even though most of the carbon remains intact. Also, thermal treatment to about 800 degrees C. under these same oxidative conditions shows a sharp decrease in surfactant adsorption of the recovered fly ash due to the fact that the carbon has been removed. This experiment simulates the various "carbon burnout" methods and is not a claim in this method. The present invention provides a thermal method of deactivating high carbon fly ash toward adsorption of AEAs while retaining the fly ash carbon. The fly ash can be used, for example, as a partial Portland cement replacement in air-entrained concrete, in conductive and other concretes, and for other applications.

  3. Passive damping technology demonstration

    NASA Astrophysics Data System (ADS)

    Holman, Robert E.; Spencer, Susan M.; Austin, Eric M.; Johnson, Conor D.

    1995-05-01

    A Hughes Space Company study was undertaken to (1) acquire the analytical capability to design effective passive damping treatments and to predict the damped dynamic performance with reasonable accuracy; (2) demonstrate reasonable test and analysis agreement for both baseline and damped baseline hardware; and (3) achieve a 75% reduction in peak transmissibility and 50% reduction in rms random vibration response. Hughes Space Company teamed with CSA Engineering to learn how to apply passive damping technology to their products successfully in a cost-effective manner. Existing hardware was selected for the demonstration because (1) previous designs were lightly damped and had difficulty in vibration test; (2) multiple damping concepts could be investigated; (3) the finite element model, hardware, and test fixture would be available; and (4) damping devices could be easily implemented. Bracket, strut, and sandwich panel damping treatments that met the performance goals were developed by analysis. The baseline, baseline with damped bracket, and baseline with damped strut designs were built and tested. The test results were in reasonable agreement with the analytical predictions and demonstrated that the desired reduction in dynamic response could be achieved. Having successfully demonstrated this approach, it can now be used with confidence for future designs as a means for reducing weight and enhancing reliability.

  4. Volcanic passive margins

    NASA Astrophysics Data System (ADS)

    Geoffroy, Laurent

    2005-12-01

    Compared to non-volcanic ones, volcanic passive margins mark continental break-up over a hotter mantle, probably subject to small-scale convection. They present distinctive genetic and structural features. High-rate extension of the lithosphere is associated with catastrophic mantle melting responsible for the accretion of a thick igneous crust. Distinctive structural features of volcanic margins are syn-magmatic and continentward-dipping crustal faults accommodating the seaward flexure of the igneous crust. Volcanic margins present along-axis a magmatic and tectonic segmentation with wavelength similar to adjacent slow-spreading ridges. Their 3D organisation suggests a connection between loci of mantle melting at depths and zones of strain concentration within the lithosphere. Break-up would start and propagate from localized thermally-softened lithospheric zones. These 'soft points' could be localized over small-scale convection cells found at the bottom of the lithosphere, where adiabatic mantle melting would specifically occur. The particular structure of the brittle crust at volcanic passive margins could be interpreted by active and sudden oceanward flow of both the unstable hot mantle and the ductile part of the lithosphere during the break-up stage. To cite this article: L. Geoffroy, C. R. Geoscience 337 (2005).

  5. Solar Electric System

    NASA Astrophysics Data System (ADS)

    1987-01-01

    Heat Pipe Technology, Inc. undertook the development of a PV system that could bring solar electricity to the individual home at reasonable cost. His system employs high efficiency PV modules plus a set of polished reflectors that concentrate the solar energy and enhance the output of the modules. Dinh incorporated a sun tracking system derived from space tracking technology. It automatically follows the sun throughout the day and turns the modules so that they get maximum exposure to the solar radiation, further enhancing the system efficiency.

  6. The Key to Me: Seniors' Perceptions of Relationship-Building with In-Home Service Providers

    ERIC Educational Resources Information Center

    Gantert, Thomas W.; McWilliam, Carol L.; Ward-Griffin, Catherine; Allen, Natalie J.

    2008-01-01

    Changing demographics and hospital downsizing have placed increasing demands on the home care sector. Many of those receiving in-home care are seniors whose chronic conditions require a collaborative approach. Both providers' paternalistic orientations toward senior clients and seniors' passivity within provider-client interactions have the…

  7. Passive cigarette smoke, coal heating, and respiratory symptoms of nonsmoking women in China

    SciTech Connect

    Pope, C.A. III Brigham Young Univ., Provo, UT ); Xu, X. )

    1993-09-01

    In this study the authors evaluated data from a sample of 973 never-smoking women, ages 20-40, who worked in three similar textile mills in Anhui Province, China. They compared prevalence rates of respiratory symptoms across homes with and without coal heating and homes with different numbers of smokers. Multiple logistic regression models that controlled for age, job title, and mill of employment were also estimated. Respiratory symptoms were associated with combined exposure to passive cigarette smoke and coal heating. Effects of passive cigarette smoke and coal heating on respiratory symptoms appeared to be nearly additive, suggesting a dose-response relationship between respiratory symptoms and home indoor air pollution from these two sources. The prevalence of chest illness, cough, phlegm, and shortness of breath (but not wheeze) was significantly elevated for women living in homes with both smokers and coal heating.

  8. Wisdom Way Solar Village: Design, Construction, and Analysis of a Low Energy Community

    SciTech Connect

    Aldrich, R.

    2012-08-01

    This report describes work conducted at the Wisdom Way Solar Village (WWSV), a community of 10 high performance duplexes (20 homes) in Greenfield, MA, constructed by Rural Development, Inc. (RDI). Building America's CARB team monitored temperatures and comfort in several homes during the winter of 2009-2010, and tracked utility bill information from 13 occupied homes. Because of efficient lights, appliances, and conscientious home occupants, the energy generated by the solar electric systems exceeded the electric energy used in most homes.

  9. Builders Challenge High Performance Builder Spotlight - NextGen Home, Las Vegas, Nevada

    SciTech Connect

    2009-01-01

    Building America Builders Challenge fact sheet on the NextGen demo home built in Las Vegas. The home has a Home Energy Rating System (HERS) index score of 44 with R-40 spray foam attic insulation, R-40 insulated concrete walls, and a 4kW DC solar laminate

  10. Solar Hot Water Heater

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The solar panels pictured below, mounted on a Moscow, Idaho home, are part of a domestic hot water heating system capable of providing up to 100 percent of home or small business hot water needs. Produced by Lennox Industries Inc., Marshalltown, Iowa, the panels are commercial versions of a collector co-developed by NASA. In an effort to conserve energy, NASA has installed solar collectors at a number of its own facilities and is conducting research to develop the most efficient systems. Lewis Research Center teamed with Honeywell Inc., Minneapolis, Minnesota to develop the flat plate collector shown. Key to the collector's efficiency is black chrome coating on the plate developed for use on spacecraft solar cells, the coating prevents sun heat from "reradiating," or escaping outward. The design proved the most effective heat absorber among 23 different types of collectors evaluated in a Lewis test program. The Lennox solar domestic hot water heating system has three main components: the array of collectors, a "solar module" (blue unit pictured) and a conventional water heater. A fluid-ethylene glycol and water-is circulated through the collectors to absorb solar heat. The fluid is then piped to a double-walled jacket around a water tank within the solar module.

  11. Very Low Energy Homes in the United States: Perspectivies on Performance from Measured Data

    SciTech Connect

    Parker, Danny S.

    2008-09-28

    This report describes how Florida Solar Energy Center measured annual performance data from a dozen recent-vintage very low energy homes in North America. Many of the designs combine greater energy efficiency with solar electric photovoltaic power in an attempt to create Zero Energy Homes. Data was also provided from the first home constructed to the German Passivhaus standard in the U.S.

  12. Adaptive passive fathometer processing.

    PubMed

    Siderius, Martin; Song, Heechun; Gerstoft, Peter; Hodgkiss, William S; Hursky, Paul; Harrison, Chris

    2010-04-01

    Recently, a technique has been developed to image seabed layers using the ocean ambient noise field as the sound source. This so called passive fathometer technique exploits the naturally occurring acoustic sounds generated on the sea-surface, primarily from breaking waves. The method is based on the cross-correlation of noise from the ocean surface with its echo from the seabed, which recovers travel times to significant seabed reflectors. To limit averaging time and make this practical, beamforming is used with a vertical array of hydrophones to reduce interference from horizontally propagating noise. The initial development used conventional beamforming, but significant improvements have been realized using adaptive techniques. In this paper, adaptive methods for this process are described and applied to several data sets to demonstrate improvements possible as compared to conventional processing.

  13. Passive containment cooling system

    DOEpatents

    Billig, Paul F.; Cooke, Franklin E.; Fitch, James R.

    1994-01-01

    A passive containment cooling system includes a containment vessel surrounding a reactor pressure vessel and defining a drywell therein containing a non-condensable gas. An enclosed wetwell pool is disposed inside the containment vessel, and a gravity driven cooling system (GDCS) pool is disposed above the wetwell pool in the containment vessel and is vented to the drywell. An isolation pool is disposed above the GDCS pool and includes an isolation condenser therein. The condenser has an inlet line disposed in flow communication with the drywell for receiving the non-condensable gas along with any steam released therein following a loss-of-coolant accident (LOCA). The condenser also has an outlet line disposed in flow communication with the drywell for returning to the drywell both liquid condensate produced upon cooling of the steam and the non-condensable gas for reducing pressure within the containment vessel following the LOCA.

  14. Passive Ball Capture Joint

    NASA Technical Reports Server (NTRS)

    Cloyd, Richard A. (Inventor); Bryan, Thomas C. (Inventor)

    2003-01-01

    A passive ball capture joint has a sleeve with a plurality of bores distributed about a circumference thereof and formed therethrough at an acute angle relative to the sleeve's longitudinal axis. A spring-loaded retainer is slidingly fitted in each bore and is biased such that, if allowed, will extend at least partially into the sleeve to retain a ball therein. A ring, rotatably mounted about the bores, has an interior wall defining a plurality of shaped races that bear against the spring-loaded retainers. A mechanized rotational force producer is coupled to the ring. The ring can be rotated from a first position (that presses the retainers into the sleeve to lock the ball in place) to a second position (that allows the retainers to springback out of the sleeve to release the ball).

  15. Passive containment cooling system

    DOEpatents

    Billig, P.F.; Cooke, F.E.; Fitch, J.R.

    1994-01-25

    A passive containment cooling system includes a containment vessel surrounding a reactor pressure vessel and defining a drywell therein containing a non-condensable gas. An enclosed wetwell pool is disposed inside the containment vessel, and a gravity driven cooling system (GDCS) pool is disposed above the wetwell pool in the containment vessel and is vented to the drywell. An isolation pool is disposed above the GDCS pool and includes an isolation condenser therein. The condenser has an inlet line disposed in flow communication with the drywell for receiving the non-condensable gas along with any steam released therein following a loss-of-coolant accident (LOCA). The condenser also has an outlet line disposed in flow communication with the drywell for returning to the drywell both liquid condensate produced upon cooling of the steam and the non-condensable gas for reducing pressure within the containment vessel following the LOCA. 1 figure.

  16. Passive focus sensor

    NASA Astrophysics Data System (ADS)

    Engelhardt, Kai; Knop, Karl

    1995-05-01

    A focus-sensor module that could take the place of the visual-image control for professional large-format cameras was fabricated. In addition, a passive focus-sensing method was shown to work at arbitrary locations and orientations in the recording plane of large-format professional cameras. A focus resolution of better than 0.1 mm and a range of measurement of +/- 5 mm at the image side were obtained at a minimum level of illuminance and with an aperture f/5.6 of the imaging lens. In the current method, three out of four images that arose from various sections of the camera's objective lens were applied for triangulation. The demonstrated approach was based on a linear photodiode array and employed one-dimensional image information for focus sensing.

  17. Passive magnetic bearing system

    SciTech Connect

    Post, Richard F.

    2014-09-02

    An axial stabilizer for the rotor of a magnetic bearing provides external control of stiffness through switching in external inductances. External control also allows the stabilizer to become a part of a passive/active magnetic bearing system that requires no external source of power and no position sensor. Stabilizers for displacements transverse to the axis of rotation are provided that require only a single cylindrical Halbach array in its operation, and thus are especially suited for use in high rotation speed applications, such as flywheel energy storage systems. The elimination of the need of an inner cylindrical array solves the difficult mechanical problem of supplying support against centrifugal forces for the magnets of that array. Compensation is provided for the temperature variation of the strength of the magnetic fields of the permanent magnets in the levitating magnet arrays.

  18. Commentary on "Capturing the Evasive Passive"

    ERIC Educational Resources Information Center

    Lillo-Martin, Diane; Snyder, William

    2009-01-01

    Passives has been the focus of much research in language acquisition since the 1970s. It has been clear from this research that young children seldom produce passives spontaneously, particularly "long" or "full" passives with a by-phrase; and they usually perform poorly on experimental tests of the comprehension of passives, especially passives of…

  19. Beaming-In On Student-Made Solar Technology

    ERIC Educational Resources Information Center

    Chiotelis, Charles L.

    1978-01-01

    Completion of a unit on heat energy motivated students to devise their own solar collectors, parabolic solar cookers, and designs for a solar home. Using their solar projects, the students tests hypotheses they might have had concerning heating capacities, insulation values, or energy conversions. (MA)

  20. DOE Zero Energy Ready Home Case Study: BPC Green Builders — Trolle Residence, Danbury, CT

    SciTech Connect

    none,

    2014-09-01

    The builder of this 1,650-ft2 cabin won a Custom Home honor in the 2014 Housing Innovations Awards. The home meets Passive House Standards with 5.5-in. of foil-faced polysiocyanurate foam boards lining the outside walls, R-55 of rigid EPS foam under the slab, R-86 of blown cellulose in the attic, triple-pane windows, and a single ductless heat pump to heat and cool the entire home.

  1. Solar technology in the Federal Republic of Germany

    NASA Technical Reports Server (NTRS)

    1979-01-01

    A series of papers dealing with the status of solar research and development in the Federal Republic of Germany are presented at a conference in Greece with the object of promoting international cooperation in solar energy utilization. The reports focus on solar collector designs, solar systems, heat pumps, solar homes, solar cooling and refrigeration, desalination and electric power generation. Numerous examples of systems produced by German manufacturers are illustrated and described, and performance data are presented.

  2. Temperature initiated passive cooling system

    DOEpatents

    Forsberg, C.W.

    1994-11-01

    A passive cooling system for cooling an enclosure only when the enclosure temperature exceeds a maximum standby temperature comprises a passive heat transfer loop containing heat transfer fluid having a particular thermodynamic critical point temperature just above the maximum standby temperature. An upper portion of the heat transfer loop is insulated to prevent two phase operation below the maximum standby temperature. 1 fig.

  3. Temperature initiated passive cooling system

    DOEpatents

    Forsberg, Charles W.

    1994-01-01

    A passive cooling system for cooling an enclosure only when the enclosure temperature exceeds a maximum standby temperature comprises a passive heat transfer loop containing heat transfer fluid having a particular thermodynamic critical point temperature just above the maximum standby temperature. An upper portion of the heat transfer loop is insulated to prevent two phase operation below the maximum standby temperature.

  4. Photovoltaic solar cell

    DOEpatents

    Nielson, Gregory N; Cruz-Campa, Jose Luis; Okandan, Murat; Resnick, Paul J

    2014-05-20

    A photovoltaic solar cell for generating electricity from sunlight is disclosed. The photovoltaic solar cell comprises a plurality of spaced-apart point contact junctions formed in a semiconductor body to receive the sunlight and generate the electricity therefrom, the plurality of spaced-apart point contact junctions having a first plurality of regions having a first doping type and a second plurality of regions having a second doping type. In addition, the photovoltaic solar cell comprises a first electrical contact electrically connected to each of the first plurality of regions and a second electrical contact electrically connected to each of the second plurality of regions, as well as a passivation layer covering major surfaces and sidewalls of the photovoltaic solar cell.

  5. Photovoltaic solar cell

    DOEpatents

    Nielson, Gregory N; Okandan, Murat; Cruz-Campa, Jose Luis; Resnick, Paul J

    2013-11-26

    A photovoltaic solar cell for generating electricity from sunlight is disclosed. The photovoltaic solar cell comprises a plurality of spaced-apart point contact junctions formed in a semiconductor body to receive the sunlight and generate the electicity therefrom, the plurality of spaced-apart point contact junctions having a first plurality of regions having a first doping type and a second plurality of regions having a second doping type. In addition, the photovoltaic solar cell comprises a first electrical contact electrically connected to each of the first plurality of regions and a second electrical contact electrically connected to each of the second plurality of regions, as well as a passivation layer covering major surfaces and sidewalls of the photovoltaic solar cell.

  6. Passive morphing of flying wing aircraft: Z-shaped configuration

    NASA Astrophysics Data System (ADS)

    Mardanpour, Pezhman; Hodges, Dewey H.

    2014-01-01

    High Altitude, Long Endurance (HALE) aircraft can achieve sustained, uninterrupted flight time if they use solar power. Wing morphing of solar powered HALE aircraft can significantly increase solar energy absorbency. An example of the kind of morphing considered in this paper requires the wings to fold so as to orient a solar panel to be hit more directly by the sun's rays at specific times of the day. An example of the kind of morphing considered in this paper requires the wings to fold so as to orient a solar panel that increases the absorption of solar energy by decreasing the angle of incidence of the solar radiation at specific times of the day. In this paper solar powered HALE flying wing aircraft are modeled with three beams with lockable hinge connections. Such aircraft are shown to be capable of morphing passively, following the sun by means of aerodynamic forces and engine thrusts. The analysis underlying NATASHA (Nonlinear Aeroelastic Trim And Stability of HALE Aircraft), a computer program that is based on geometrically exact, fully intrinsic beam equations and a finite-state induced flow model, was extended to include the ability to simulate morphing of the aircraft into a "Z" configuration. Because of the "long endurance" feature of HALE aircraft, such morphing needs to be done without relying on actuators and at as near zero energy cost as possible. The emphasis of this study is to substantially demonstrate the processes required to passively morph a flying wing into a Z-shaped configuration and back again.

  7. EBIC Characterization and Hydrogen Passivation in Silicon Sheet

    NASA Technical Reports Server (NTRS)

    Hanoka, J. I.

    1985-01-01

    As a general qualitative tool, the electron beam induced current (EBIC) method can be very useful in imaging recombination in silicon sheet used for solar cells. Work using EBIC on EFG silicon ribbon is described. In particular, some efforts at making the technique more quantitative and hence more useful, some limitations of the method, and finally specific application to hydrogen passivation is treated. Some brief remarks are made regarding the technique itself.

  8. A comparison of the solar-gas and solar-electric interface

    NASA Astrophysics Data System (ADS)

    Mannella, G. G.

    1982-01-01

    The introduction of large-scale solar-derived gas, electricity, and home heat into the national pipeline, electric grid, and fuel supply systems is discussed. Natural gas is shown to be substitutable for most other energy sources, having a lower cost per energy unit than electricity or oil, and able to be augmented by biomass derived methane or solar derived hydrogen. The latter is perceived as an unproven technology, both economically and technically. Solar home heating systems will lower the utilities' rate base and lead to minimum charge rates for solar customers and higher rates for regular customers unless utilities are permitted to enter the solar heating business as an extension of their role as a service institution. Dispersed solar electric systems are seen to be the least economical use of solar systems, while the solar-gas system offers the greatest potential as a bridge for solar technologies into residential, institutional, and commercial markets.

  9. Passive Smoking and Breast Cancer Risk among Non-Smoking Women: A Case-Control Study in China

    PubMed Central

    Li, Bin; Wang, Lian; Lu, Min-Shan; Mo, Xiong-Fei; Lin, Fang-Yu; Ho, Suzanne C.; Zhang, Cai-Xia

    2015-01-01

    Background The role of passive smoking on breast cancer risk was unclear. This study aimed to evaluate the association between passive smoking and breast cancer risk among Chinese women. Methods/Principal Findings A hospital-based case-control study, including 877 breast cancer cases and 890 controls, frequency-matched by age and residence, was conducted. A structured questionnaire was used to collect information on passive smoking history through face-to-face interview by trained interviewers. Unconditional logistic regression models were used to estimate the association between passive smoking and breast cancer risk. A positive association between any passive smoking exposure and breast cancer risk was observed. Compared with women who were never exposed to passive smoking, women who were ever exposed had a higher breast cancer risk, with the adjusted odds ratio (OR) and 95% confidence interval (CI) of 1.35 (1.11-1.65). Similar result was found on home passive smoking exposure and breast cancer risk, but not on workplace passive smoking exposure. Women who were ever exposed to tobacco smoke at home had a higher risk of breast cancer compared with never exposed women, with the adjusted OR (95% CI) of 1.30 (1.05-1.61). Home passive smoking exposure showed significant dose-response relationships with breast cancer risk in smoker-years, cigarettes/day and total pack-years (Ptrend=0.003, 0.006 and 0.009, respectively). An increased total smoker-years of any passive exposure significantly elevated the risk of breast cancer (Ptrend<0.001). Positive associations and dose-response relationships were found among postmenopausal women and all subtypes of estrogen receptor (ER) and progesterone receptor (PR) status of breast cancer. Conclusions Passive smoking was associated with an increased risk of breast cancer among non-smoking Chinese women. A stronger positive association with breast cancer risk was seen mainly among postmenopausal women. PMID:25915759

  10. Home Energy Assessments

    ScienceCinema

    Dispenza, Jason

    2016-07-12

    A home energy assessment, also known as a home energy audit, is the first step to assess how much energy your home consumes and to evaluate what measures you can take to make your home more energy efficient. An assessment will show you problems that may, when corrected, save you significant amounts of money over time. This video shows some of the ways that a contractor may test your home during an assessment, and helps you understand how an assessment can help you move toward energy savings. Find out more at: http://www.energysavers.gov/your_home/energy_audits/index.cfm/mytopic=11160

  11. Home Energy Assessments

    SciTech Connect

    Dispenza, Jason

    2010-01-01

    A home energy assessment, also known as a home energy audit, is the first step to assess how much energy your home consumes and to evaluate what measures you can take to make your home more energy efficient. An assessment will show you problems that may, when corrected, save you significant amounts of money over time. This video shows some of the ways that a contractor may test your home during an assessment, and helps you understand how an assessment can help you move toward energy savings. Find out more at: http://www.energysavers.gov/your_home/energy_audits/index.cfm/mytopic=11160

  12. Solar heating system

    SciTech Connect

    Larkin, W.J.

    1984-01-31

    A solar heating system is provided incorporating the flat plate collector and storage tanks substantially in the same unit and avoiding the usual reverse-siphon problems that are inherent in the nature of a passive integral system of this type by a piping system wherein heating and elevation of certain vertical components of connecting piping reverses, or almost reverses, the usual net pressure head which is responsible for creating the reverse siphon.

  13. Semantic home video categorization

    NASA Astrophysics Data System (ADS)

    Min, Hyun-Seok; Lee, Young Bok; De Neve, Wesley; Ro, Yong Man

    2009-02-01

    Nowadays, a strong need exists for the efficient organization of an increasing amount of home video content. To create an efficient system for the management of home video content, it is required to categorize home video content in a semantic way. So far, a significant amount of research has already been dedicated to semantic video categorization. However, conventional categorization approaches often rely on unnecessary concepts and complicated algorithms that are not suited in the context of home video categorization. To overcome the aforementioned problem, this paper proposes a novel home video categorization method that adopts semantic home photo categorization. To use home photo categorization in the context of home video, we segment video content into shots and extract key frames that represent each shot. To extract the semantics from key frames, we divide each key frame into ten local regions and extract lowlevel features. Based on the low level features extracted for each local region, we can predict the semantics of a particular key frame. To verify the usefulness of the proposed home video categorization method, experiments were performed with home video sequences, labeled by concepts part of the MPEG-7 VCE2 dataset. To verify the usefulness of the proposed home video categorization method, experiments were performed with 70 home video sequences. For the home video sequences used, the proposed system produced a recall of 77% and an accuracy of 78%.

  14. Solar astronomy

    NASA Technical Reports Server (NTRS)

    Rosner, Robert; Noyes, Robert; Antiochos, Spiro K.; Canfield, Richard C.; Chupp, Edward L.; Deming, Drake; Doschek, George A.; Dulk, George A.; Foukal, Peter V.; Gilliland, Ronald L.

    1991-01-01

    An overview is given of modern solar physics. Topics covered include the solar interior, the solar surface, the solar atmosphere, the Large Earth-based Solar Telescope (LEST), the Orbiting Solar Laboratory, the High Energy Solar Physics mission, the Space Exploration Initiative, solar-terrestrial physics, and adaptive optics. Policy and related programmatic recommendations are given for university research and education, facilitating solar research, and integrated support for solar research.

  15. DOE Zero Energy Ready Home Case Study: Nexus EnergyHomes, Frederick, Maryland

    SciTech Connect

    none,

    2013-09-01

    This urban infill community with 24 duplexes, 19 townhomes, and 7 single-family homes features SIP walls, geothermal heat pumps, solar PV, and a proprietary energy management system. The builder won a 2013 Housing Innovation Award in the production builder category.

  16. Solar energy thermalization and storage device

    DOEpatents

    McClelland, John F.

    1981-09-01

    A passive solar thermalization and thermal energy storage assembly which is visually transparent. The assembly consists of two substantial parallel, transparent wall members mounted in a rectangular support frame to form a liquid-tight chamber. A semitransparent thermalization plate is located in the chamber, substantially paralled to and about equidistant from the transparent wall members to thermalize solar radiation which is stored in a transparent thermal energy storage liquid which fills the chamber. A number of the devices, as modules, can be stacked together to construct a visually transparent, thermal storage wall for passive solar-heated buildings.

  17. Solar energy thermalization and storage device

    DOEpatents

    McClelland, J.F.

    A passive solar thermalization and thermal energy storage assembly which is visually transparent is described. The assembly consists of two substantial parallel, transparent wall members mounted in a rectangular support frame to form a liquid-tight chamber. A semitransparent thermalization plate is located in the chamber, substantially paralled to and about equidistant from the transparent wall members to thermalize solar radiation which is stored in a transparent thermal energy storage liquid which fills the chamber. A number of the devices, as modules, can be stacked together to construct a visually transparent, thermal storage wall for passive solar-heated buildings.

  18. Solar Energy Education. Industrial arts: student activities. Field test edition

    SciTech Connect

    Not Available

    1981-02-01

    In this teaching manual several activities are presented to introduce students to information on solar energy through classroom instruction. Wind power is also included. Instructions for constructing demonstration models for passive solar systems, photovoltaic cells, solar collectors and water heaters, and a bicycle wheel wind turbine are provided. (BCS)

  19. Solar Energy Reporting

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Last year the people of Cleveland, Ohio were troubled by natural gas shortages during one of the coldest winters on record. The severe winter generated a great deal of interest in solar energy as an alternative source of heat. Home owners, home builders and civic officials wanted to know just how much solar energy is available in Cleveland. Now they get a daily report through the city's news media, from information supplied as a community service by NASA's Lewis Research Center. Lewis routinely makes daily measurements of solar energy as part of its continuing research in behalf of the Department of Energy. The measuring device is a sun sensor called a pyranometer (upper photo) located atop a building at the NASA Center. To make the information conveniently available to news media, Lewis developed a Voice Output Integrating Insolometer, an automated system that acquires information from the sun sensor and translates it into a recorded telephone message. The Lewis pyranometer collects sun data for 15 hours daily and measures the total solar energy yield. For reporting to the public, the information is electronically converted to a specific reading. A media representative calling in gets a voice-synthesized announcement of a two or three digit number; the number corresponds to the kilowatt-hours of solar energy that would be available to a typical 500-square-foot solar collector system. Response in Cleveland has been favorable and interest is developing in other parts of the country.

  20. Alternatives to Nursing Homes

    MedlinePlus

    ... this website may not be available. Alternatives to nursing homes Before you make any decisions about long ... live and what help you may need. A nursing home may not be your only choice. Discharge ...