biofuels: an important part of a low-carbon diet

The Union of Concerned Scientists advocates for a 'count carbs and make carbs count' approach to transportation fuels, emphasizing the need for life cycle emissions analysis to distinguish between high-carbon fuels like liquid coal and low-carbon alternatives like cellulosic ethanol. The report highlights that while some biofuels can significantly reduce emissions, others may increase them depending on feedstock and land use. It promotes the adoption of Low Carbon Fuel Standards, citing California's model, to drive the market toward sustainable, low-carbon fuels and avoid the high emissions associated with liquid coal and tar sands.

• Transportation-related emissions account for nearly 40 percent of the total global warming pollution in the United States.
• Biofuels exhibit a wide range of global warming impacts based on their feedstock and production process; for example, cellulosic ethanol can reduce emissions by more than 85 percent, while corn ethanol's impact varies from cutting emissions by over 50 percent to increasing them relative to gasoline.
• Certain alternative fuels significantly increase emissions compared to gasoline, with liquid coal increasing emissions by more than 80 percent and gasoline from tar sands increasing them by approximately 14 percent.
• There is a lack of scientific consensus on a single analytical approach for biofuel life cycle analysis, with primary debates centering on process emissions, fertilizer use, data quality, and the impact of land use changes.
• The report's scenarios for displacing 37 billion gallons of gasoline show that a low-carbon scenario utilizing advanced biofuels could reduce pollution by over 244 million metric tons (mmt) CO2eq, whereas a high-carbon scenario relying on liquid coal would increase pollution by 233 mmt CO2eq.
• Performance-based policies like California's Low Carbon Fuel Standard are recommended because they use carbon intensity criteria rather than picking specific winning fuels, thereby encouraging reductions across the entire fuel supply chain.
• While low-carbon fuel standards address global warming pollution and some environmental issues like fertilizer runoff, they do not address all harmful impacts, specifically social issues such as food pricing and access.

APA

Union of Concerned Scientists (n.d.). biofuels: an important part of a low-carbon diet. https://www.ucs.org/sites/default/files/2019-10/executive-summary-ucs-biofuels-report.pdf

Chicago

Union of Concerned Scientists. biofuels: an important part of a low-carbon diet. n.d. https://www.ucs.org/sites/default/files/2019-10/executive-summary-ucs-biofuels-report.pdf.

Wikipedia

{{cite report |author=Union of Concerned Scientists |title=biofuels: an important part of a low-carbon diet |url=https://www.ucs.org/sites/default/files/2019-10/executive-summary-ucs-biofuels-report.pdf |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{unionofconcernedscientistsndbiofuels, author = {{Union of Concerned Scientists}}, title = {{biofuels: an important part of a low-carbon diet}}, institution = {Union of Concerned Scientists}, url = {https://www.ucs.org/sites/default/files/2019-10/executive-summary-ucs-biofuels-report.pdf}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }