From Buses to Trains, Renewable Diesel Catches On in California

For almost two years, MUNI's diesel-powered buses in San Francisco have run entirely on renewable diesel fuel. Diesel-powered Amtrak trains running from San Jose to Sacramento could be next.

3 minute read

September 16, 2017, 11:00 AM PDT

By Irvin Dawid


Renewable Diesel

California Air Resources Board / Flickr

"On Aug. 28, a train between Oakland and Auburn [Placer County, Calif.] began running entirely on the fuel from Golden Gate Petroleum of Martinez — part of a test that, if successful, could herald its use throughout the Capitol Corridor system and in trains statewide," reports Isha Salian for the San Francisco Chronicle.

Planetizen reported on Dec. 14, 2015 that all San Francisco-owned vehicles running on diesel fuel, including its Muni bus fleet, transitioned from a biodiesel blend to 100 percent renewable diesel. Salian adds that Oakland and the San Jose Unified School District have also phased in renewable diesel, "and operators of San Francisco Bay ferries are looking at it too."

The Bay Area is rapidly becoming a center for renewable diesel, which can be made from vegetable oils, restaurants' oil waste or animal fats — material known in the industry as biomass. Unlike biodiesel, which has to be mixed in with petroleum diesel, the new fuel can go into a tank at 100 percent strength.

Demand for the product in California largely stems from the establishment of the Low Carbon Fuels Standards program by the California Air Resources Board, part of the Global Warming Solutions Act of 2006, signed by Gov. Arnold Schwarzenegger. His 2007 executive order (pdf) also established a statewide goal to reduce the carbon intensity of California's transportation fuels by at least 10 percent by 2020.

Gov. Jerry Brown's Executive Order B-30-15 included a goal of reducing (fossil) petroleum consumption 50 percent by 2030, furthering the push toward biofuels.

Demand skyrocketed from 2011 to 2016, from 2 million gallons to 250 million gallons used last year. According to CARB, this is about 7 percent of all diesel used in the state, writes Salian.

'We can sell every drop of renewable diesel we make,' said Eric Bowen, head of corporate business development for the Renewable Energy Group. The company sells the fuel mostly to the California market, he said. Its Louisiana plant can produce 75 million gallons of renewable diesel each year, and it is looking to expand its facilities.

According to an email from Tom Fulks of the Diesel Technology Forum, Gold Gate Petroleum purchases renewable diesel from Iowa-based Renewable Energy Group or Finland-based Neste, the world's largest producer, which they sell under their Neste MY Renewable Diesel brand.

"Simon Mui, senior scientist at the Natural Resources Defense Council (NRDC), said that depending on what the renewable diesel is made from, it can cut lifecycle greenhouse gas emissions by 15 to 80 percent," adds Salian. "Renewable diesel also reduces fine particle pollution and other types of emissions, like nitrogen oxides and carbon monoxide, Mui said."

Challenges

Some experts question how much the renewable diesel market can grow.

'The more we study biofuels, the less clear it is there's very much of a sustainable supply,' said Daniel Kammen, a UC Berkeley professor who helped write California's Low Carbon Fuel Standard. Biofuels are always less efficient than electric vehicles, he said.

While electrifying public transit buses has made enormous progress lately, heavy trucks will still be a challenge.

Sam Wade, chief of the transportation fuels branch at the Air Resources Board, said that while heavy-duty vehicles may eventually switch to electric power, 'there's not that many applications that are fully viable today. We see (renewable diesel) as a nice near-term opportunity.'

'We don't meet our state goals unless we have a full array of those electrified fleets as well as liquid-fuel-based fleets,' adds Mui of NRDC.

Next step for Capitol Corridor

If further tests go well, all Capitol Corridor trains could switch over to renewable diesel by next summer, according to Dean Shepherd, manager of mechanical services.

Jim Allison, manager of planning, Capitol Corridor, estimates that shifting to renewable diesel in all of its locomotives, which each need about 70 gallons of fuel per hour, would reduce the trains' greenhouse gas emissions by two-thirds. 

For in-depth information on renewable diesel, see this 2010 evaluation of renewable diesel by UC Berkeley, UC Davis and the California Environmental Protection Agency.

Thursday, September 14, 2017 in San Francisco Chronicle

portrait of professional woman

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban Planner

Get top-rated, practical training

High-rise apartment buildings in Waikiki, Hawaii with steep green mountains in background.

Study: Maui’s Plan to Convert Vacation Rentals to Long-Term Housing Could Cause Nearly $1 Billion Economic Loss

The plan would reduce visitor accommodation by 25,% resulting in 1,900 jobs lost.

April 6, 2025 - Honolulu Civil Beat

Wastewater pouring out from a pipe.

Alabama: Trump Terminates Settlements for Black Communities Harmed By Raw Sewage

Trump deemed the landmark civil rights agreement “illegal DEI and environmental justice policy.”

April 13, 2025 - Inside Climate News

Blue and white Seattle Link light rail train exiting concrete Downtown Bellevue Tunnel in Bellevue, WA.

Why Should We Subsidize Public Transportation?

Many public transit agencies face financial stress due to rising costs, declining fare revenue, and declining subsidies. Transit advocates must provide a strong business case for increasing public transit funding.

April 7, 2025 - Todd Litman

Silhouette of man holding on to back of bicycle ridden by woman with Eiffel Tower in background.

Paris Bike Boom Leads to Steep Drop in Air Pollution

The French city’s air quality has improved dramatically in the past 20 years, coinciding with a growth in cycling.

3 hours ago - Momentum Magazine

Multifamily housing under construction.

Why Housing Costs More to Build in California Than in Texas

Hard costs like labor and materials combined with ‘soft’ costs such as permitting make building in the San Francisco Bay Area almost three times as costly as in Texas cities.

4 hours ago - San Francisco Chronicle

Western coyote looking at camera in grassy field.

San Diego County Sees a Rise in Urban Coyotes

San Diego County experiences a rise in urban coyotes, as sightings become prevalent throughout its urban neighbourhoods and surrounding areas.

5 hours ago - Fox 5