The project employed a single 250-kilowatt FuelCell Energy, Inc. fuel cell, which uses digester gas as a fuel. The methane content of the digester gas is 62 percent. The project began operation in September 2004.
The project incorporates a waste-heat recovery hot-water generator and an SCS-designed/fabricated digester gas pressurization/ treatment skid. The skid removes moisture, particulates, hydrogen sulfide, halogenated compounds and siloxanes. The hot water is used to heat the wastewater treatment plant’s anaerobic digesters, which frees up additional digester gas for power generation. The entire power plant, including digester gas supply and hot water interfaces, are under the control of an-SCS designed/fabricated SCADA system.
The power plant operates in parallel with Southern California Edison (SCE) as a baseload unit. The power plant displaces power otherwise bought from SCE at retail rates. The project qualifies for net metering under California regulations.
SCS executed the project on a turnkey basis. The total power plant capacity is 250 kW. The project was the first digester gas fueled fuel cell in California. It was decommissioned in the autumn of 2009.
SCS Engineers’ responsibilities: