Lars Smith makes an interesting point.

The demand for biofuels is driving the destruction of forests and the emission of greenhouse gasses. . .

If CO2 offsets make sense in aviation (a rather large “if”), then people who use biofuels in their cars should buy offsets to make up for the CO2 emission caused by the deforestation taking place when biofuel plantations are established.

This is, as Lars notes, absurd. All of the convoluted carbon wheezes - subsidies, mandates, credits, taxes etc. - are making things worse. Lars has a better idea.

A sensible first step would be to get rid off all subsidies for biofuels.