U.S. Department of Energy - Energy Efficiency and Renewable Energy

Federal Energy Management Program

New and Underutilized Technology: Solar Water Heating

The following information outlines key deployment considerations for solar water heating within the Federal sector. This information spans:

• Benefits
• Application
• Climate and Regional Considerations
• Key Factors for Deployment
• Ranking Criteria
• Resources

Benefits

Solar water heating uses solar thermal collectors to heat water.

Application

Solar water heating is applicable in most building categories.

Climate and Regional Considerations

Solar water heating is best in regions with high insolation.

Key Factors for Deployment

The Energy Independence and Security Act (EISA) of 2007 requires 30% of hot water demand in new Federal buildings and major renovations to be met with solar water heating equipment providing it is life-cycle cost effective.

Federal agencies must consider collector placement location to optimize solar water heating efficiency.

Ranking Criteria

Federal energy savings, cost-effectiveness, and probability of success are ranked 0-5 with 0 representing the lowest ranking and 5 representing the highest ranking. The weighted score is ranked 0-100 with 0 representing the lowest ranking and 100 representing the highest ranking.

Resources

The following resources are available:

• Solar Water Heaters: Energy Savers overview of solar hot water heaters presented by the U.S. Department of Energy.

• ENERGY STAR Solar Water Heaters: Overview, specifications, buying guidance, and frequently asked questions for ENERGY STAR-qualified solar water heaters.

• Solar Hot Water Resources and Technologies: FEMP list of Federal technology and application resources covering solar hot water.

• Technical Potential of Solar Water Heating to Reduce Fossil Fuel Use and Greenhouse Gas Emissions in the U.S.: National Renewable Energy Laboratory (NREL) overview of the technical potential of solar water heating in residential and commercial buildings

• Parabolic-Trough Solar Water Heating: Federal technology alert covering renewable technologies for reducing water-heating costs.

• Solar Water Heating: Energy Efficiency and Renewable Energy Clearinghouse report on solar water heating technologies (1996).

• Solar Hot Water Heating Systems: Pacific Gas and Electric (PG&E) presentation originally presented in March 2010.

• Lessons for Better Solar Water Heating: Presentation given at the American Council for an Energy-Efficient Economy (ACEE) Hot Water Forum in May 2010.

• Solar Hot Water Basics: Renewable Energy Resource Center overview of solar hot water technologies and applications.