Grant to Fund 'Brown Grease' Biodiesel Plant

San Francisco Mayor Gavin Newsom, joined the California Energy Commission, U.S. Environmental Protection Agency, and the National Biodiesel Board (NBB) recently to announce an innovative state and federal grant-funded biofuel project by the San Francisco Public Utilities Commission (SFPUC) that will potentially serve as a model for cities throughout the nation.

One million dollars from the California Energy Commission will galvanize the city’s first brown grease-to-biodiesel plant to break new ground for sustainable fuel production in California, with the U.S. EPA’s grant ensuring it serves as a tangible model -- via a "how-to" manual or open source toolkit -- for cities across the entire nation to replicate the project.

This project makes full use of the "brown grease" that is currently discarded as waste. Brown grease is the mix of used oils and food scrapings that flow down the sink drain during dishwashing, food preparation, and daily cleaning. In commercial kitchens, before brown grease has a chance to enter the sewer pipes, it is captured in a mechanism called a "grease trap." Putting this previous waste-only product to use, San Francisco will refine brown grease collected from restaurants and residents and create multiple types of alternative energy.

The pilot project is a joint public-private collaboration between the SFPUC, BlackGold Biofuels, and URS. The brown grease biodiesel plant will be constructed at the award-winning Oceanside Treatment Plant next to the San Francisco Zoo. It will be the first of its kind combining a sewage treatment plant with this new technology to generate three different types of alternative energy sources:

  • 1. High-grade, road-worthy certified biodiesel for vehicles;
  • 2. Lower grade boiler fuel for running sewage treatment plant equipment; and
  • 3. Converted methane to run the treatment plant.

The program is an extension of the SFPUC’s existing SFGreasecycle program that since 2007 has been collecting used cooking oil for free and recycling it into biodiesel. In addition to providing a renewable fuel source, the diversion of the Fats, Oils, and Grease (FOG) helps save cities money from costly grease-related sewage backups. The SFPUC estimates that grease blockages in San Francisco sewers account for 50 percent of all sewer emergencies and annually costs the city $3.5 million in cleanings.

Sewage treatment plants account for three percent of the nation’s electrical consumption because they run 24 hours a day, seven days a week. By keeping grease out of the sewers and reducing reliance on outside energy sources, projects like the SFPUC’s brown-grease to biodiesel project are a win-win for ratepayers and the environment.

"This is the perfect marriage between local sewage plants and the ability to generate a sustainable resource for the benefit of the public and the environment," said SFPUC General Manager Ed Harrington.