San Francisco has kicked off a pilot programme that would make it the first US city to convert used cooking grease into biofuels.

Funded by state and federal grants, the $1.2 million (US) programme is expected to start up by the end of this year.

“Thanks to these collective grants, our cutting-edge brown-grease-to-biodiesel plant will break new ground toward accessible, sustainable energy and serve as a model for the entire state and the country,” said San Francisco Mayor Gavin Newsom.

By collecting so-called “brown grease” for refining, the city expects to not only produce three types of fuel — biodiesel for vehicles, boiler fuel and methane — but to better prevent costly backups caused by grease buildup in sewer systems.

City officials estimate that grease blockages currently causes a full 50 percent of the city’s sewer problems at a cost of $3.5 million a year.

“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 Ed Harrington, general manager of the San Francisco Public Utilities Commission.

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