An Essential Technology

Heating water in California homes and businesses accounts for roughly 3% of total statewide greenhouse gas emissions. Given the state target of reducing emissions to near zero by mid-century, we cannot afford to leave a solution to a significant portion of the problem untapped. Solar thermal technologies can effectively help meet the hot water needs of homes and industrial facilities from the pollution-free heat of the sun.  A growing solar thermal market also supports local jobs, including manufacturing jobs.  In fact, California is home to seven solar thermal manufacturers across the state.

California supports solar water heating and cooling technologies, also called solar thermal, through the CSI-Thermal rebate program. Unfortunately, the program was designed at a time of high natural gas prices and the California Public Utilities Commission was very slow to readjust. The California Solar & Storage Association petitioned the CPUC multiple times to raise incentive levels and effective rebate levels were finally put in place in May 2015. Since then, program activity has increased, with some of the greatest growth within the multi-family housing sector.  

We secured a two-year extension of this program when AB 797 (Irwin) was signed into law in the fall of 2017.  Assemblymember Jacqui Irwin championed the law that extended the program for two more years to 2020.  The law directs 50% of the funding for solar thermal projects on low income housing and in disadvantaged communities, as they should be a central focus of the state’s growing solar thermal market. The law also targets 10% of resources to this sector, enabling solar thermal systems for the largest users of natural gas. The CSI-Thermal program will continue to support jobs, manufacturing, and economic development opportunities across the state.

For more information on Solar Thermal, please check out these fact sheets on rooftop solar thermal technologies and AB 797.

CSI-Thermal Step 1 Rebate Levels ($ per therm)

CSI-Thermal Step 1 Rebate Levels ($ per therm)