Does biodiesel use raise NOx emissions?
Blends of less than 5% do not have a measurable affect on NOx. For B20 blends, vehicle testing that is ongoing at NREL is finding no significant impact on NOx, however engine test stand studies find that B20 increases NOx emissions by about 2% over conventional diesel. However, it is possible that some B100 can raise NOx above the certification limits of CI engines. Biodiesel blends used in heating oil equipment will reduce NOx by 1% for every 1% of biodiesel used in the blend. A B20 with heating oil will reduce NOx by 20%.
