Metro buses to switch to state-grown canola-seed fuel

King County Metro buses will switch from soy-based biodiesel to biodiesel made from canola seeds grown in Washington state.

Currently, most of Metro's buses use a combination of 20 percent soy biodiesel and 80 percent low-sulfur diesel. The soy is grown in Iowa.

At a news conference today, King County Executive Ron Sims said the county has purchased 2 million gallons of biodiesel made with canola seeds from Sunnyside, enough to provide 20 percent of bus fuel for a year.

"We need a new model of sustainability if we are ever going to reduce enough greenhouse-gas emissions to stabilize the climate," Sims said.

He said this partnership "closes the loop" between the production and refinement of biodiesel, and hopefully it will support the market for the fuel, which is considered more environmentally friendly than fossil fuels.

The canola fuel will cost the county $640,000 more than the soy fuel. Farmers will pay the county for 115,000 tons of biosolids produced by the county's wastewater treatment plants, which will be used to fertilize the canola fields. For three months of waste, farmers have paid the county $34,000.

The county teamed with Natural Selections Farms in Sunnyside, which built a seed-crushing facility.

King County is the largest biodiesel customer in the state, according to Sims.

Sharon Pian Chan: 206-464-2204 or schan@seattletimes.com