Energy & Sustainability Projects

    To meet the goals of the Carbon Free Water by 2015 Program, the Sonoma County Water Agency has implemented several energy production, energy efficiency, and sustainability projects. Below is the list of projects completed and currently underway.

    Geothermal Resource Analysis

    The Water Agency contracted Earth Systems Sciences LLC to conduct a study to characterize and analyze potential impacts of geothermal resources on hydrogeological resources in a small region of Sonoma Valley. Hovering questions preceding this study included: Is there significant geothermal heat generated in this region? Where is the main point source of heat in the study area? Does the magnitude of geothermal heat in this area have capacity for renewable power generation or for renewable heating of buildings or other commercial assets? Would utilizing this resource jeopardize the groundwater resource in these areas? Previous studies have been performed in this area in the 1970's and 1980's. But using a new approach to conduct modeling of subsurface geothermal resources, 'maximum likelihood' scenarios were generated to better describe the resource. This approach analyzed several factors (water chemistries, hydrologic properties, etc.) and determined that the south western quadrant of the study area showed signs of a sizable geothermal resource. In the study area, the historical maximum temperature readings were up to 185 degrees Fahrenheit at surface depth levels of 0.36 mi. Conclusions from the report analysis identify likely greater heat capacity of up to 230 degrees Fahrenheit at a depth greater than 0.8 mi. However there are some downsides to utilizing this resource in which the Water Agency needs to consider. The first being that extraction may only be achieved at low flow rates (no more than 95 gal/hr). In other circumstances, a higher flow rate could cause negative impacts on entities previously utilizing the resource. Regardless of the model results, if geothermal extraction applications are pursued, a sophisticated monitoring program should be put in place to assure the impacts are detected quickly and remediated. 


    Photovoltaic Systems

    Photovoltaic Systems

    The Agency has four photovoltaic systems that total to about 2 MW (megawatt). The administration building has a 0.5 MW system that has panels flush on the roof and panels on a carport-like structure in the parking lot.  The Airport Larkfield Wastewater Treatment Plant has a 0.5 MW fixed system that is ground mounted around the edge of one of the storage ponds. The Sonoma Valley Wastewater Treatment Plant has a 1.0 MW tracking system that is ground mounted in a field adjacent to a storage pond.  The Agency continues to investigate additional opportunities for solar power generation. The most recent ground mounted solar installment is that of Geyserville Treatment Plant, which has a 50 kW (kilowatt) system. For more information, visit the Photovoltaic Systems page.


    Photovoltaic Systems

    Floating Solar PV System

    From September 2016 through March 2017, a pilot floating solar photovoltaic (PV) system was deployed on our Oceanview recycled water pond just north of Santa Rosa. This 40 foot by 40 foot floating system supported 40 PV panels. Eight 2-ton piles of rock support cables attached to the aluminum support structure mounted on 30 polyethylene floats. Pristine Sun monitored the floating PV system movement, flexibility, temperature, cable tension, and other variables during the pilot test. The floating PV system weathered the wettest winter in Sonoma County recorded history without sinking, capsizing, buckling, or taco-ing. Pristine Sun is currently designing a full scale 1 megawatt floating PV system on the Oceanview pond. After appropriate permits and approvals are in place, the Water Agency would ultimately purchase the power produced from the Oceanview floating PV system to cost effectively offset power consumed at the Oceanview recycled water pump station and 49 other Water Agency power accounts.



    Warm Springs Hydroelectric Dam

    After the Warm Springs Dam was completed in 1984, a hydroelectric turbine was installed a few years later and has been producing electricity since the late 1980s.  This turbine is capable of generating 2.6 MW of electricity.  Since energy production is influenced by the flow of water through the dam, power production is usually at about 1.3 MW.  Annual energy production ranges from 9,000 MWh to 15,000 MWh.  The Agency collaborates with the Army Corps of Engineers in the operation of the hydroelectric dam.

    Warm Springs Hydroelectric Dam

    Wind Turbine - Geyserville Sanitation Zone

    On Thursday January 3rd 2013, a wind turbine was erected at the Geyserville Sanitation Zone wastewater treatment plant. 

    The purpose of this partially grant funded project is to develop, test and demonstrate a model for a locally owned, cost-effective, renewable wind energy that would help Sonoma County reach its greenhouse gas reduction goals and help the Water Agency reach its goal of delivering Carbon Free Water by 2015.

    Learn more about the Geyserville Sanitation Zone Wind Turbine

    Wind Turbine - Geyserville Sanitation Zone

    Community Choice Aggregation (Sonoma Clean Power)

    On March 22, 2011, the Sonoma County Water Agency Board of Directors directed the Water Agency to investigate Community Choice Aggregation (CCA) while concurrently approving the Water Agency’s Energy Policy. Community Choice Aggregation allows one or more cities and/or counties to form a service area that provides for the option to purchase power generation from local sources that has a different electricity mix than that of the original investor owned utility. Creating competition in the electricity generation market, by creating choice in energy providers, is good for the community and the environment by driving electricity rates to be most competitive while also having a choice in the types of energy you can purchase. Transmission, distribution, customer service and billing remain the same (delivered through the existing utility PG&E). Customers within this service area can opt out of participating in the CCA program and continue to receive their power generation services through the existing investor owned utility--although the starting generic rate for Sonoma Clean Power's Clean Start Program is cheaper than that of PG&E. Learn more about Sonoma Clean Power.

    Community Choice Aggregation

    Energy Efficiency Improvements

    In the years following the purchase of the administration building, several projects have been implemented to reduce facility’s power requirements.  Energy efficiency improvements included window film application, lighting retrofits, and LED installation.  The window film saves energy by reducing the amount of heat transferred through the glass.  This means that less energy is used to regulate the internal climate of the facility, because there is less of an external influence.  The film application has a lifetime of 15 years and saves the Agency approximately 30,000 kWh annually.  Almost half of the lighting retrofits were paid for through the Association of Bay Area Governments.  The savings were achieved by pairing higher quality tubes with more efficient ballasts and eliminating unnecessary lights (aka delamping) in areas of low usage.  More than 600 fixtures were retrofitted and provides the Agency approximately 62,000 kWh in annual savings.  Each of the 16 LED tubes used to replace fluorescent tubes have lifetime of 50,000 hours, which last twice as long as the best fluorescent tubes in the market today.  The Agency saves approximately 300 kWh annually, assuming 40 hours of weekly operation for 52 weeks. Learn more about the GeoExchange project.

    Energy Efficiency

    Hybrid, Plug-In Hybrid & Electric Vehicle Fleet

    The Water Agency is currently greening our fleet with electric, plug-in hybrid, and hybrid vehicles. To reduce the greenhouse gas emissions from its transportation needs, the Agency purchased its first hybrid electric vehicle in 2006. As of 2017, the Agency has 26 hybrid, plug-in hybrid and electric vehicles, comprising almost 20% of the entire fleet. The Water Agency has joined a coalition of Bay Area local governments to pursue a grant through the Metropolitan Transportation Commission to fund fleet electric vehicles and charging infrastructure. Through the grant, the Water Agency has received funding to supplement the purchase of five electric vehicles. In addition to charging stations already located at several Water Agency facilities, five charging stations are planned for installation by the end of the year through the grant. Learn more about our Electric Vehicle Fleet.

    Hybrid and Plug-In Hybrid vehicles

    Recycling Program

    The Agency has an active recycling program at its administration building and its operations and maintenance center.  Paper, plastics, glass, and aluminum cans are all recycled with the help of designated bins in the kitchens, copy rooms, conference rooms, and cubicles.  Recycled paper is ordered for copiers and printers and recycled presentation materials are used whenever possible.  The Agency also participates in recycling ink cartridges from its printers.  Opportunities to recycle e-waste are also available and bins are provided on site for Agency employees annually.

    Recycling Program

    Water Education & Conservation Programs

    The Agency has well-established water education and conservation programs. For more information about the Water Education program, click here.  For more information about the Water Conservation Program, click here.

    Water Education Program