RENEWABLE DIESEL / BIODIESEL

The American Trucking Associations cautiously embraced the use of biodiesel in blends up to 5 percent in its perennial war to increase the diesel fuel supply.  The ATA policy requires that all biodiesel used meet strict quality standards, that only blends of less than 5% be used, and that state boutique fuel mandates be avoided. 

Biodiesel is a diesel fuel alternative that is made from renewable resources, such as vegetable oils or animal fats.  Biodiesel is made through a chemical process called transesterfication, whereby vegetable oil is mixed with methanol in the presence of a catalyst (sodium hydroxide) to produce a diesel fuel alternative.  The resulting liquid must then be further processed to remove glycerin and excess methanol.  To be designated as biodiesel the alternative fuel must meet the American Society of Testing Materials (ASTM) D6751 quality standards, compliance with which assures that biodiesel may be used in low percentage blends without causing problems for the diesel engine. 

Renewable diesel is a diesel fuel alternative that is made from renewable resources, such as vegetable oils or animal fats.  Renewable diesel is sometimes referred to as second or third generation biodiesel, depending upon the production process utilized.  The primary differences between biodiesel and renewable diesel are the technologies used to make the fuel and the molecules that are ultimately produced.  Whereas, biodiesel is made using a chemical reaction called transesterfication, renewable diesel is made using a thermal or other chemical reaction.  The resulting diesel fuel product is a fully fungible fuel that can be transported via pipeline. 

The most significant difference between biodiesel and renewable diesel is that renewable diesel can meet the ASTM D975 quality standard, which is the existing standard for on-road diesel fuel.  Renewable diesel has not been subjected to rigorous on-road fleet testing; however, preliminary information indicates that renewable diesel may have advantages over biodiesel for the end-user.  These advantages may include a higher energy content and better cold weather performance compared to biodiesel.