City’s Restaurant Grease Re-Used To Power Municipal Vehicles

By: Jason Callicoat, Querrey & Harrow

Jason Callicoat, Querrey & Harrow Courtesy of Querrey & Harrow

When San Francisco Mayor Gavin Newsom decided that the all city vehicles using diesel fuel should be converted to run on biodiesel, an important part of the conversion plan was the city’s “Greasecycle” program. That program allows San Francisco city restaurants and other food service establishments to sign up for free collection of their used cooking grease. The city collects the grease, which is then converted into biodiesel and used to power municipal buses, fire trucks, street sweepers and other vehicles that formerly ran on diesel fuel.

While participation in the Greasecycle program is voluntary, the conversion of city vehicles to biodiesel was not. Mayor Newsom issued Executive Directive 06-02, which required that all diesel vehicles owned by the city be converted to run on B20 biodiesel, a blend of 20% biodiesel and 80% petroleum diesel, by December 31, 2007. “The city made that deadline,” said Karri Ving, Biofuel Coordinator for San Francisco’s Public Utilities Commission. The city’s fleet of 1,500 diesel vehicles was converted to run on B20 biodiesel by December 1, 2007.

The Mayor’s Executive Directive further orders that all diesel-using departments shall then pursue additional increases in the use of biodiesel through the use of greater-than 20% blends and/or neat biodiesel (B100). There is no deadline to begin using the higher blends of biodiesel, although the Public Utilities Commission has already started.

“We have our own very small fleet of two collection vehicles that run on B100,” Ving said, referring to the vehicles that collect used cooking oil from about 550 establishments, including restaurants, hotels, cafeterias in hospitals, and other food service businesses. The city collects this waste oil free of charge, and restaurants and other business establishments can sign up online for the service. The city will pick up the used grease as frequently as needed.
“Before, private haulers would charge restaurants to collect their grease, but when the city started doing this for free, the private haulers dropped their price to zero,” Ving said.

However, private haulers sometimes prefer to deal with large hotels and other big establishments that can provide a large amount of used oil for each collection trip. The city is willing to provide free collection service to some of the smaller mom and pop establishments that are not as attractive to commercial haulers, “because that keeps the grease out of the sewers and re-directs it for use as biofuel,” Ving said.  

When used grease gets into the city sewers, it can clog pipes and damage pumping stations.  The Public Utilities Commission then has to spend tax dollars to unclog the pipes and repair the pumping stations.

The city has established a Commercial Waste Oil Transfer Station to handle all the material from commercial establishments (residents of the city may also collect their own cooking grease and take it to drop-off points to be used in the Greasecycle program). From there, the material is sold to local plants to be processed into biodiesel.  

Biodiesel is a cleaner-burning alternative to diesel fuel. Biodiesel itself contains no petroleum and is produced from used cooking grease, such as vegetable oil and animal fats. It can be blended at any level with petroleum diesel to make a biodiesel blend. Biodiesel can be used in diesel engines with little or no modification, and it is biodegradable and non-toxic.

The city currently uses four local plants on a rotating basis to turn the collected grease into biodiesel. “The city is evaluating the plants to put together a set of criteria that will eventually be used to award contracts for production of biodiesel for the city,” Ving said. For example, in awarding contracts for biodiesel production, the city may eventually consider whether the plants use biodiesel to power their own vehicles, how far away the plants are, and the quality of the biodiesel produced.

Earlier this year, Mayor Newsom announced that San Francisco had received a $1 million grant from the California Energy Commission, to build the City’s own grease-to-biodiesel production facility. “The facility is expected to be completed by June of 2009,” Ving said. The new facility will be part of a pilot program that will accept “brown grease,” not just the “yellow grease” that is left over from restaurant fryers. “Brown grease” consists of pan scrapings and washed oil residue trapped in grease traps/interceptors under a restaurant sink. The Mayor’s office estimates there are more than 2.5 million gallons of brown grease in the city, compared with 1.5 million gallons of "yellow grease" like fryer oil. Biodiesel is more readily converted from yellow grease using the current technology available to the city.

Although facilities currently exist and are in development in other parts of the country that convert brown grease to biodiesel (some after rendering that grease), the new San Francisco city-owned facility will first evaluate whether it is economically feasible to turn brown grease into high quality or a lower grade biodiesel.  “Turning the brown grease into biodiesel would fill a hole that currently exists [in the San Francisco area], in that the private producers typically don’t touch the brown grease,” which is harder to convert than the yellow grease,” Ving said.

Jason Callicoat can be reached via e-mail at jcallicoat@querrey.com