Work on a cogeneration system at the city’s wastewater treatment plant will be finished this fall, wrapping up a year-long undertaking to reduce energy costs and environmentally damaging emissions.
The new cogeneration/grease receiving system, a joint undertaking between the city and Chevron Energy Solutions, will create and use methane biofuel — gas produced from restaurant grease — that will increase the amount of green power generated at the plant by approximately 40 percent, Public Works Director Ron Popp said.
Construction started in the fall, after officials identified the equipment that, at between 20 and 50 years old, has outlived its usefulness.
The plant had a small internal combustion generator — which is approximately 50 years old — fueled by methane from the plant’s digesters. But the city found that it could significantly reduce costs by using this naturally produced methane to make the electricity and heat needed to power the plant itself.
The project should be finished in October or November.
Estimated cost for the project is $5.5 million, generated from Certificates of Participation, sanitation and enterprise funds and a $200,000 grant from PG&E.
City officials expect that the high price tag will also be offset by the expected $112,000 in annual energy savings from this new method, Popp said. The city also plans on charging 12 cents per gallon for restaurants to dump their kitchen grease, which is expected to be another source of valuable revenue.
Meanwhile, a $32 million project to remodel the whole plant is getting under way. The city plans on opening the bids for the project next spring.
Community Development Director Ralph Petty said a number of funding sources contributing to the Millbrae Station Area development impact fees will make up a significant amount of funding for the project.
The remodeling project will also be funded by redevelopment agency funds and, officials hope, a low-interest loan from the state that could save the city between $1.5 million and $7 million over the life of the loan, Popp said.