At its 40-acre site, the Point Loma Wastewater Treatment Plant treats approximately 175 million gallons of wastewater per day generated by the 2.2 million area residents.
In 2011, the plant partnered with BioFuels Energy, LLC, which built California’s first commercial project to purify wastewater digester gas and feed it back into the natural gas pipeline system. The biomethane generated from the process is enough to power 4.5 MW of renewable, highly efficient, fuel cell generation.
Prior to 2011, the plant was flaring more than 1.3 million cubic feet of digester gas – which is 60 percent methane – into the atmosphere every day.
UC San Diego uses biomethane from the Point Loma facility to power a 2.8-megawatt fuel cell. They then use the byproduct heat from the fuel cell generation process as a continuous power source for 320 tons of chilling capacity to cool campus buildings, increasing the overall efficiency of the power plant and generating cost savings for the university.
The South Bay Water Reclamation Plant in San Diego uses biomethane from the from the Point Loma facility to power a 1.4-megawatt fuel cell. This municipal facility is a pump station that does not generate biogas on site. The fuel cell power plant will provide reliable base-load power around-the-clock, replacing power purchased from the electric grid. Byproduct heat will be used for heating needs at the pump station, increasing the overall efficiency of the power plant.
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