In a fight to reduce greenhouse gas emissions, California’s Air Resources Board has spent years looking for the cleanest, most efficient ways to cut carbon. Turns out, biodiesel is at the top of the list.
On September 25, the board finalized California’s revised Low Carbon Fuels Standard. The new standard affirms biodiesel reduces greenhouse gas emissions by at least 50% and often by as much as 81% versus petroleum. This gives biodiesel the best carbon score among all liquid fuels.
“Biodiesel is the most sustainable fuel on the planet,” said Don Scott, National Biodiesel Board director of sustainability. “Low carbon alternatives can also be low cost alternatives when we use diverse supplies of renewable resources. This validates that California’s carbon reduction goals are obtainable.”
As part of the state’s low carbon fuel standard, the Air Resources Board has refined comprehensive lifecycle analysis to quantify the carbon intensity of conventional and alternative fuels. More than seven years of analysis have gone into addressing questions, including indirect land use change. California’s lifecycle model incorporates all the impacts for producing a fuel’s raw materials including conversion and transportation. The model also includes the indirect economic impacts of growth in global agriculture — making it one of the most thorough and rigorous evaluations ever done to quantify the environmental footprint of biofuels.
The findings echo what the U.S. Environmental Protection Agency determined five years ago in establishing the federal Renewable Fuel Standard. Under that program, biodiesel qualifies as an Advanced Biofuel, with the EPA analysis showing that it reduces carbon emissions from 57% to 86%.
“California’s analysis, which has been validated by independent academic review, provides confidence that biodiesel is, without question, a more sustainable alternative for transportation fuel. The commercial success of the growing biodiesel industry suggests goals to further reduce greenhouse gases and displace imported petroleum are appropriate and achievable. With a focus on carbon reduction and the national policy to support it, biodiesel could reduce carbon emission by 40 million tons annually,” said Scott.
The estimates provided for likely fuel pathways include:
- ULSD (standard diesel) 102.76 g/MJ
- Gasoline 99 (CaRFG) g/MJ
- Corn Ethanol 80.09 g/MJ
- Compressed Natural Gas 79.46 g/MJ
- Soy 51.83 g/MJ
- Used Cooking Oil 19.87 g/MJ
- Tallow 32.83 g/MJ
- Canola 50.23 g/MJ
- Corn oil 28.68 g/MJ
These scores are reported in grams of carbon dioxide equivalent per megajoule of fuel. All of the feedstocks listed for biodiesel are used in significant volumes. Weighting these scores by the amount of each feedstock used nationally in 2014, suggests that the average biodiesel in the market has a carbon intensity of 38.4 g/MJ. — giving it the lowest carbon intensity of any category of liquid or gaseous fuel, and making it competitive with electric vehicles as a carbon mitigation strategy.
“This is not an academic exercise. It’s where the rubber hits the road in determining where Californians get their fuels for the next 20 or 30 years,” said Scott. “It’s the difference between continuing the status quo of oil dependence and stimulating the development of cleaner alternatives. CARB should be commended for its leadership and for taking a bold approach. We are proud that biodiesel is part of the solution.”