diesel99B99 Biodiesel is a hh-level biofuel blend consisting of up to 99.9 percent biodiesel and 0.1 percent petroleum diesel. B99 and other hh-level blends (B100) are less common than B20 and other low-level blends.Click here to access the PDF version of this factsheet. Date: February 21, 2025. View changes since posting in the PDF version. Specific details on the renewable diesel fuel