Biodiesel and Renewable Diesel Basics

What Are Biodiesel and Renewable Diesel?

Biodiesel and renewable diesel are advanced, sustainable biofuels produced from an increasingly diverse mix of resources such as recycled cooking oil, soybean oil, and animal fats. These fuels are renewable, clean-burning alternative fuels that can be used today in existing diesel engines without modification. They are among the most sustainable, advanced biofuels, commercially produced in the United States.

Biodiesel and Renewable Diesel Standards

Both biodiesel and renewable diesel must be produced to strict specifications to ensure proper performance. Biodiesel blends meet specifications for legal diesel motor fuel (ASTM D7467). Prior to blending, pure biodiesel, known as B100 (100% biodiesel) must meet the ASTM definition for biodiesel itself (ASTM D6751).

Renewable diesel, a product different than biodiesel must meet ASTM D975, the petroleum diesel standard. Biodiesel and renewable diesel which meet their respective specifications can also be blended together for a highly sustainable, 100% renewable fuel.

Raw vegetable oil and animal fats cannot meet these diesel fuel specifications and therefore are not considered biodiesel or renewable diesel.

Producing Biodiesel and Renewable Diesel

Biodiesel is made through a chemical process called transesterification whereby the glycerin is separated from the fat or vegetable oil. The process leaves behind two products — methyl esters and glycerin.

Renewable diesel is most commonly made from the same diverse mix of fats, oils, and greases. However, unlike biodiesel which uses a relatively benign reaction, the process by which renewable diesel is made is more akin to traditional petroleum refining and can be described by three main steps including hydrotreating, isomerization, and fractionation.

Growth of an Industry

Biodiesel’s growth has been careful and deliberate. The industry understood that if it was going to market a sustainable product, that it must focus on sustainability from the onset. Growing from 20 million gallons in 2003 to over 2.8 billion gallons in 2019 and supporting nearly 60,000 jobs, biodiesel and renewable diesel have become America’s most successful advanced biofuel.

Biodiesel and Renewable Diesel Availability

Biodiesel and renewable diesel are available nationwide and blends over 4 percent are required to be labeled at the pump. Biodiesel and renewable diesel can be purchased through distributors or at retail locations.

Sustainability

New land is not required for biodiesel production. Instead, this advanced biofuel uses readily available, diverse resources. And that is not all. Biodiesel has several environmental benefits when compared to petroleum-based diesel fuel:

  • Reduces lifecycle greenhouse gases by 86%.
  • Lowers particulate matter by 47%, reduces smog, and makes our air healthier to breathe.
  • Reduces hydrocarbon emissions by 67%.
  • For every unit of fossil energy, it takes to produce biodiesel, 3.5 units of renewable energy are returned, the best of any U.S. fuel.