San Francisco ended its use of petroleum diesel
They replaced it with renewable diesel, a change that will achieve a significant 50 percent greenhouse gas emissions reduction.
“As the global climate negotiations conclude, San Francisco and cities worldwide must continue to lead by taking bold actions that reduce greenhouse gas emissions immediately,” said Mayor Lee.
“These actions cannot wait. San Francisco has ended its use of petroleum diesel to fill up the city’s fleet of vehicles and will significantly reduce greenhouse gas emissions and improve air quality for our residents immediately today.”
San Francisco completed the switch to renewable diesel at all of the city’s fueling sites. The city’s Fleet Management Division estimates a 50 percent reduction, or 50,000 metric tons, in greenhouse gas emission as a result of ending the use of petroleum diesel and replacing it with renewable diesel.
Using renewable diesel will also reduce the emissions of harmful air pollutants that harm the health of local residents and which disproportionately hurt San Francisco’s low-income communities because so much heavy duty vehicle traffic occurs in and near those communities.
In Fiscal Year 2014, the city used 5.8 million gallons of diesel fuel, of which 4.9 million was petroleum diesel, resulting in the emission of approximately 100,000 metric tons of greenhouse gases into the atmosphere.
The city maintains a robust fleet of vehicles, and 1,966 vehicles that rely on diesel fuel are affected by this change. This change will completely end the use of petroleum diesel at the 53 city-run fueling facilities immediately.
The switch to renewable diesel is part of the city’s ongoing efforts to reduce emissions in its fleet and combatting climate change. The city started using cleaner forms of diesel fuel by transitioning to a blend of biodiesel.
Before the switch to renewable diesel, most of the municipal fleet was using B20, which is 20 percent biodiesel and 80 percent petroleum diesel.
Renewable diesel is not the same as biodiesel. Both fuels are produced from numerous bio-feedstock sources, including fats, oils and greases, but the two fuels are produced through different processes. Renewable diesel uses a hydrogenation process, while biodiesel uses an esterification process.
According to the California Air Resources Board, the full lifecycle emissions of carbon from renewable diesel produced from sustainable sources are more than 60 percent lower than either petroleum or B20 biodiesel.
Chemically, renewable diesel is indistinguishable from petroleum diesel, and testing has shown it to have engine performance that matches or outperforms both petroleum diesel and biodiesel. ■