A recent ruling from a court in California is not expected to have much of an impact on biodiesel. California’s Fifth District Court of Appeal ruled provisionally that Poet LLC’s lawsuit against the California Air Resources Board (CARB) about the state’s low carbon fuel standard (LCFS) program can continue to operate. This article from Biodiesel Magazine says the set aside of CARB’s deferment of formulating mitigation measures for possible NOx increases from biodiesel will be avoided if it’s found that no mitigation measures are needed.
To the extent that violations occurred, it appears the ruling was more about technicalities than anything substantive. Since CARB will have the opportunity to address the violations without interuption to the LCFS program, sources say it should not have much impact on biodiesel. It does, however, appear to prompt CARB to act sooner rather than later on the contentious subject of biodiesel NOx emissions.
While biodiesel significantly reduces nearly all tailpipe emissions such as particulate matter and carbon monoxide compared to petroleum diesel exhaust, early EPA engine dynamometer tests showed a slight increase in NOx emissions from biodiesel. NOx consists of nitric oxide (NO) and nitrogen dioxide (NO2), which, together with volatile organic compounds (VOCs), produce smog and ground-level ozone (O3), compounds that degrade air quality and pose significant health hazards.
Years later, those same early emissions tests that showed slight NOx increases from biodiesel came under scrutiny; the tests are said to be too narrow and they do not represent the breadth of types of diesel engines, duty cycles and test loads operating in the real world. Later studies conducted by U.S. DOE, National Renewable Energy Laboratory, Texas A&M University, the North Carolina Department of Transportation, and the U.S. Navy suggest biodiesel blends such as B20 are NOx neutral.
POET filed the original lawsuit in January 2012 and alleged the environmental impacts of the LCFS were not adequately studied and, therefore, the program should be discontinued. But the court has ruled the regulations are staying in effect this year until corrective action is completed.