SAN FRANCISCO, CA - A demonstration plant at the Oceanside Wastewater Treatment Plant in San Francisco has begun using restaurant trap grease to produce biodiesel.

Developed by URS Corp., the project relies on a demonstration treatment plant capable of processing 10,000 gallons per day of trap waste, recovering 300-500 gallons a day of brown grease and converting it to biodiesel. 

The program is an extension of the San Francisco Public Utilities Commission's (SFPUC) SFGreasecycle program ( to prevent fats, oils and grease from being released into city sewers. In sewers, these materials solidify and constrict wastewater flow, causing backups and damage to sewer lines.

For the past three years, the SFPUC and URS have worked to develop a program that considers the needs of restaurant operators, city government, residents, environmental agencies and the commercial grease industry.

The demonstration plant is expected to save about 1,200 metric tons of carbon dioxide equivalents a year with a commercial-scale facility of more than 40,000 metric tons a year. A URS-developed, 12-month research and testing program will be used to monitor the brown grease recovery and biodiesel production plant's performance and to establish a business case that other municipal agencies can replicate.

The program was financed by federal funds and approximately $1 million from the California Energy Commission.