As of January 1, 2021, total U.S. biofuels plant production capacity reached 21 billion gallons per year (gal/y) (or 1.3 million barrels per day [b/d]), as reported by 278 facilities. Fuel ethanol producers accounted for 85% of U.S. total biofuels production capacity, followed by biodiesel producers at 11%, and the remaining 4% by other renewable fuel producers.