Rialto, California teams with Chevron to turn restaurant grease into renewable power
Chevron Energy Solutions has begun engineering and construction of an innovative system at the City of Rialto’s wastewater treatment facility that will transform wastewater sludge and kitchen grease from local restaurants into clean, renewable power.
The environmentally friendly system will increase municipal revenues, reduce landfill wastes and lower greenhouse emissions by nearly 5.5 million tons annually, while decreasing the city’s energy costs by about $800,000 a year.
The system includes a 900-kilowatt fuel cell power plant, manufactured by FuelCell Energy, that will generate electricity without combustion - using methane, a biogas produced naturally on site by the organic materials contained in wastewater.
The new system will provide a beneficial use for the thousands of gallons of fats, oils and grease (FOG) that are washed daily from restaurant grills and pans. The watery liquid is collected by grease hauling companies and often disposed of in landfills, where it releases methane as it decomposes.
At the Rialto facility, a FOG-receiving station will provide an effective disposal alternative, reducing the amount of FOG sent to landfills. It also will provide a revenue stream to the city through “tipping fees” paid by grease haulers for each disposal. Meanwhile, the fuel cell plant and other energy-efficient improvements will reduce greenhouse gas emissions by 11 million pounds of carbon dioxide annually, equivalent to removing 1,080 cars from the road each year.
In Rialto, a Los Angeles suburb of about 100,000 residents, forecasted population growth necessitated the expansion and upgrade of the city’s aging wastewater treatment facility. The project, which costs $15.1 million, is eligible for a $4.05 million rebate on the fuel cell plant cost from California’s Self-Generation Incentive Program, administered by Southern California Gas. The remaining cost will be self-funded through energy cost savings and FOG station revenues, without any impact on local taxpayers.
Chevron Energy Solutions will proceed with engineering and construction of the project over the next few months. Project highlights include installation of the FOG-receiving station; repairs to the current digester equipment, where methane is naturally produced from organic matter; a new automation system and controls; a high-efficiency boiler; and three 300-kilowatt Direct FuelCell® units that will convert methane into hydrogen and then use the hydrogen to generate power electrochemically, without combustion. In addition, the residual waste heat from the fuel cells will be put to work to warm the digesters to human body temperature, to stimulate further methane production.
Fuelcell Energy sold its fuel cell plant to Rialto through Chevron Energy Solutions and will maintain the plant after it is installed. Because of its ultra-clean emission profile, the plant meets California’s stringent air quality standards and is expected to be sited easily. It will also provide baseload power around the clock.