At AutoblogGreen we have discussed many times the potential of biogas (usually biomethane) for different industries. The fact is that it's a flammable gas that is produced by the natural fermentation of waste and/or trash. In most of our landfills, this gas is just expelled to the atmosphere. Methane is claimed to be one of the gases that cause the greenhouse effect.
The use of methane in cars is somewhat limited (although it can potentially be mixed with CNG), many are very interested in using it to generate electricity. In 2006, the EU produced 5.3 oil-equivalent tons of this gas, which is 13.6 percent more than in 2005.
The latest efforts, however, seem to prefer extracting biomethane from agricultural waste instead of landfills, because if obtained from a coherent source, the purity of the gas can be better assured. This guarantees it can satisfy the standards that make it usable as a fuel.
According to a recent article in The Lancet, farming is responsible of 20 percent of greenhouse gas emissions. 30.5 percent of this is gas which is produced by manure (and off the record, 25 percent is direct consequence of the animals' digestion process). There's great interest in capturing that 30.5 percent of currently unused energy.
ProBiogás, a comprehensive R+D European plan that unites 12 research centers and 14 companies, has announced that 2007 is marked as "Biogas year". We'll keep our eyes open.
[Source: Energías Renovables (link is in Spanish)]