Over 15 percent of America’s biodiesel and renewable diesel is made from recycled cooking oil, such as that used in fryers. Another 13 percent comes from animal fats. These are two examples of the wide variety of biodiesel feedstocks that use rendered products as a low carbon fuel.
Because of their chemical composition, fats release concentrated amounts of energy when burned. This energy can be used as a biofuel. Current usage of rendered fats in the biofuels is estimated at 3–8% of the approximate 11 billion pound annual production of rendered fats (yielding 43 million to 116 million gallons of biodiesel). Existing biodiesel technology yields a gallon of fuel for each 7.6 lbs of fat.
In addition to biofuels, the application of rendered products to the production of energy and other industrial uses is under examination.