How is biodiesel produced?

Biodiesel, also called biogas oil, is made from vegetable oil obtained after the processing of seeds—a process called “crushing”—or from the recovery of used oil. Any vegetable oil can be used to produce biodiesel. In France, rapeseed oil is the main oleaginous-protein seed used for biodiesel production.

Rapeseed indeed has a good yield while being an important resource for certain pollinator species such as bees. Thanks to its deep roots, it is also an asset for protecting soils against erosion. As for its production, the oil is extracted from the seed, then mixed with an alcohol—ethanol or methanol—and a catalyst, either sodium or potassium hydroxide, which promotes the chemical reaction. This process results in esterification, producing a fatty acid methyl ester (FAME), the essential component of biodiesel sold in France under names such as “Diester” or “Oleo100,” depending on its origin and composition.

Biodiesel production plays a key role in both energy and food sovereignty. Thanks to the vegetable oils and proteins sector, France meets 100% of its citizens’ needs for edible oils and more than 50% of livestock protein requirements (compared to around 30% on average in the rest of Europe).

For rapeseed, for example, its processing simultaneously produces oil and proteins (meal) for livestock. Thus, 71% of the seed is used for food, and only 29% for non-food outlets such as biodiesel.