G:
Geothermal Technologies Legacy Collection - A subject-specific Web portal for legacy geothermal energy technology that includes a distributed search capability and full-text access, when available (1970's forward) [Department of Energy (DOE)]

Geothermal Technologies Program - Expertise in advanced power plant systems, small-scale power plants, and direct-use performance [Department of Energy (DOE), National Renewable Energy Laboratory (NREL)]

I:
Idaho National Laboratory Geothermal Program - Works in partnership with U.S. industry to establish geothermal energy as an economically competitive contributor to the U.S. energy supply [Department of Energy (DOE), Idaho National Laboratory (INL)]

R:
Renewable Resources Maps and Data (NREL) - Provides high-quality renewable energy resource data for U.S. and international locations [Department of Energy (DOE), National Renewable Energy Laboratory (NREL)]