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On all major projects, the District engages the local power utility for review and suggestions on 
enhancing efficiency in the project.  

Have completed and are undertaking numerous projects resulting from an Integrated Energy Audit 
completed in cooperation with Pacific Gas and Electric.   

Projects include installation of a more energy efficient digester mixing system and installation of 
premium-efficiency motors when replacing pumps.  

Performance Measures & Results 

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Optimize energy management: Operation of treatment plant processes involving major 
equipment, such as tertiary filter backwash pumps, are adjusted to occur during periods of the 
day when they can be powered by the District’s renewable energy sources rather than imported 
electrical power.  

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Decision-making using life cycle cost (LCC) analysis:  Equipment selection decisions for recent 
major maintenance and capital projects have been based on a life-cycle cost analysis to ensure 
that energy efficiency plays a key role in decision making.  

   

ENERGY GENERATION & RECOVERY  

 

Internal energy sources evaluated (e.g., biogas, hydropower, heat in wastewater), and/or 
renewable energy sources evaluated on an ongoing basis (e.g., solar, wind, co-digestion)  

 

Recovery of digester gas in a combined heat and power (CHP) system, and boilers in place (for 
process and building heating)   

 

Solar panels, wind turbines, heat recovery, in conduit hydro, and/or hydroelectric power 
generation systems installed  

The District has worked to expand its energy independence through energy efficient designs and the 
incorporation of multiple alternative energy initiatives.  The plant is powered in part by wind turbines, 
hosts a one-megawatt solar facility, and utilizes a cogeneration system that uses byproducts of 
wastewater treatment to create energy used onsite.    

Using the LystaMize product from the OMRC will increase gas production and increase the electricity 
production from the District’s cogeneration engines.  The technology will be applied to other organics in 
the solid waste stream to generate more gas for cogeneration or for transportation fuel.  

The District’s wastewater facilities are the first in the state of California to be powered in part by wind 
turbines.   

The District is one of the founding agencies in the 19 member Bay Area Biosolids to Energy Coalition that 
has been driving biosolids to energy solutions for the San Francisco Bay Area.  There are 5 projects 
underway in the Bay Area that will increase energy from biosolids that are currently landfilled or land 
applied.  

 Performance Measures & Results 

Renewable energy utilized:  In 2015, nearly 2.5 million kWh produced from solar farm and wind 
turbines, or approximately 23% of total imported energy.