San Francisco Department of the Environment

Multi-Family – 15 Units in NoPa

Solar Domestic Hot Water for Multi-tenant Building

As the proud owner of four apartment buildings in San Francisco, Linda Erkelens has been doing everything she can to reduce her buildings’ energy and water use. In November 2009, she installed a solar water heating (SWH) system on her 15-unit building on Hayes St, the third of her four properties being outfitted with this renewable energy technology.

Linda knows that being green and saving money means more than installing solar. She has also taken a comprehensive approach to water use in her buildings, using simple water conservation tools to get even better results from her SWH system. “I did every building,” Linda said. “We went through all the units and did all the measures recommended by the San Francisco Public Utilities Commission water auditors. They were so cool! They gave me boxes of kitchen faucet aerators and low-flow showerheads to install.”

Linda’s system was installed by SunWater Solar and uses 8 Schüco Premium LA collectors. At 232 sq ft of collector area, the system is expected to provide over 60% of the energy needed for domestic water heating each year at this location, significantly reducing her natural gas cost. The system includes two 120 gallon Rheem Solar Tanks that supply the pre-heated water from the solar system to the existing hot water storage tank, for a total of 360 gallons of storage capacity. A Schüco monitoring system with SunReports allows Linda and SunWater Solar to view and track the performance of the system over the internet, helping ensure that energy production is optimized over the system’s lifespan, expected to be 25 years or more. This system is helping Linda control costs where she can. “My water bills are high, my garbage is high, my electricity is reasonable, and my gas bills are coming down. I don’t think I can do anything about the garbage, but the water is just going to keep skyrocketing because of water and sewer use.”

Chris Chappell of SunWater Solar offered, “Linda is definitely a San Francisco hero of apartment energy and water upgrades!”

city seal png