Biodiesel vs renewable diesel
Two different fuels that share feedstocks and get confused constantly.
Biodiesel is produced by transesterification and consists of fatty acid methyl esters. It has excellent lubricity but poorer cold-flow behaviour and shorter storage life.
Renewable diesel is hydrotreated to produce true hydrocarbons, giving it storage and cold-weather behaviour equivalent to petroleum diesel and no blend restrictions.
Biodiesel can be made at small scale with appropriate equipment and controls. Renewable diesel cannot — it needs refinery infrastructure.
Educational overview only. Before acting on any of this, review the safety fundamentals and local regulations.