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

Building Technologies Office – Utility Solar Water Heating Initiative


The following materials provide additional information on USH2O and are listed alphabetically. For more detail, contact us. Some of the following documents, as indicated, are available as Adobe Acrobat files (PDFs).

Break-Even Cost for Residential Solar Water Heating in the United States: Key Drivers and Sensitivities — This paper examines the break-even cost for residential rooftop solar water heating (SWH) technology, defined as the point where the cost of the energy saved with a SWH system equals the cost of a conventional heating fuel purchased from the grid (either electricity or natural gas). The break-even cost for the largest 1,000 electric and natural gas utilities serving residential customers in the United States as of 2008 is examined.

Bringing Solar Thermal Energy into Renewable Portfolio Standards and the Green Power Market — A short article summarizing the potential for solar water heating and its value for renewable portfolio standards and green pricing programs. This paper is based on a presentation made at the Solar 2004 Conference of the American Solar Energy Society and is posted with the permission of Robert M. Reedy.

Field Performance of Solar Water Heating Systems — This report was written by the Florida Solar Energy Center in 1994 to examine the energy savings, demand savings, and reliability of solar water heating systems from the results of field monitoring studies, many of which were sponsored by utilities. The report reviews the first generation of programs from the late 1970s to early 1980s, the second generation in the mid 1980s, and the third generation of programs in the early 1990s.

Individual Utility Article — Some utilities offer articles describing the programs. The articles may be found under individual listings in Utility Partners.

Solar Thermal Business Prospectus — A detailed sample business plan for bringing profitable solar water heating services to customers in investor-owned or municipal utility environments.

Solar Water Heating Pilot Program: Final Evaluation Report — This report, prepared by Itron, was published in March 2011 and presents a comprehensive evaluation of the 30 month of California Solar Water Heating Pilot Program (SWHPP) that addressed both residential and commercial customer bases in the San Diego area. The SWHPP was established in 2007 by California Public Utilities Commission (CPUC) to "promote the use of that (solar water heating) technology and reduce demand for natural gas." This report analyzes cost, performance, bill savings, public attitudes, and other market conditions relevant to the SWH market in California.

The Technical Potential of Solar Water Heating to Reduce Fossil Fuel Use and Greenhouse Gas Emissions in the United States — This report was written by Paul Denholm of the National Renewable Energy Laboratory (NREL) in March 2007, and provides an overview of the technical potential of solar water heating to reduce fossil fuel consumption and associated greenhouse gas emissions in U.S. residential and commercial buildings. The technical potential of SWH was evaluated in terms of end-use energy reduction, primary energy reduction, and CO2 emissions reduction.

Utility Success Stories In Solar Water Heating — A summary of the leading solar water heating programs in the United States, including goals, lessons learned, and key data. This paper was presented at the Solar 2003 Conference of the American Solar Energy Society and is posted with permission from the organization.

The Value Proposition of Solar Water Heating In California — This study was commissioned by the California Solar Energy Industries Association (CALSEIA) to analyze and quantify the value of solar water heating in terms of direct and indirect natural gas savings, avoided emissions, hedge against gas price volatility, and job creation potential.