In theory, biofuels are an appealing climate change solution. They derive the carbon inside them from atmospheric CO2 and their energy from the sun. They can be used in existing vehicles and generators, and store a lot of energy per unit of volume or weight. The raw materials can be grown in many places, without massive capital investment. Of course, recent history has given scientists and policymakers an increasingly clear understanding of the many problems with biofuels. A report (PDF) from Scientific Committee on Problems of the Environment (SCOPE) of the International Council for Science (ICSU) concludes that, so far, biofuel production has actually produced more emissions than using fossil fuels would have. Partly, this is on account of the nitrous oxide emissions associated with the use of artificial fertilizers in agriculture. Over a 100 year period, one tonne of nitrous oxide causes as much warming as 310 tonnes of carbon dioxide. Corn produces especially large amounts of nitrous oxide, because it has a shallow root system and only takes in nitrogen for a few months each year.
It is possible that better feedstocks, agricultural techniques, and biofuel production processes will eventually make these fuels ecologically viable. Not all transportation can be electrified, and there will probably always be industrial processes that require petroleum-like feedstocks. Nonetheless, it must be recognized that the world has been going about biofuel production in the wrong way. That is something that should be borne in mind particularly by the citizens of states that are lavishing government support on them, both in the form of subsidies and by mandating that they comprise a certain proportion of transportation fuels.