The National Renewable Energy Laboratory, provides a number of resources by which to learn more about solar energy and solar hot water heating systems for your home.

They also offer the Renewable Resource Data Center which provides numerous resources on solar radiation including an extensive collection of renewable energy resource data, maps, and tools. There is also biomass, geothermal, solar, and wind resource data for locations throughout the United States.

The US Department of Energy Consumer´s Guide to Energy Efficiency and Renewable Energy provides additional information on Solar Hot Water Heaters and Solar Swimming Pool Heaters.

The Database of State Incentives for Renewables and Efficiency website provides a searchable comprehensive database of state, local and utility based incentives.

The Solar Energy International organization is a nonprofit resource for education and training programs on renewable energy.