Here’s an interesting biodiesel stat:

[T]he region’s supply of fryer grease is limited. Each Oregonian contributes about a gallon of used cooking oil a year to the grease market, according to Sequential Pacific. If all the used grease went to biodiesel production, the state’s producers would have only half of what they need to meet demand for the fuel.

That’s really not much grease—especially considering that Oregon residents consume about a gallon and a half of highway fuels per person each day. So as much as I love biodiesel, fryer grease just isn’t going to power rush hour.