Biodiesel. It’s safe, biodegradable, renewable and it produces fewer pollutants than petroleum-based diesel. Still, there are a couple of drawbacks to this fuel. A big one is that it is not widely available at marinas yet. It also is less stable than petroleum-based diesel fuel, which means it degrades faster. This article from Soundings’ July issue has more.
This video has more on biofuels:
