Organic matter, such as agricultural waste, heated in the absence of oxygen splits into two types of material: a charcoal (biochar), and hydrocarbon gases and liquids. When added to soils, the charcoal can provide a powerful fertiliser. The hydrocarbons can be burnt, either to generate electricity or to power an internal combustion engine.
Biochar is exciting growing attention around the world. Charcoal’s ability to improve soils can sometimes be spectacular. But more importantly from a climate change perspective, charcoal is almost pure carbon and is strangely stable in soils. It seems to persist for centuries. Charcoal can therefore offer substantial opportunities for long-term sequestration of carbon. The valuable fuels from the biogases and liquids are also carbon-neutral since they contain CO2 previously captured during photosynthesis. As a third major benefit, soils fertilised with charcoal seem to need less artificial fertiliser, thus saving fossil fuels. Fewer applications of fertiliser would reduce the level of emissions of nitrous oxide, a particularly dangerous greenhouse gas.
Biochar manufacture represents a way of productively storing large amounts of carbon. But the carbon in the charcoal could be burnt to generate electricity instead of being stored in soil. Current emissions trading schemes, such as the European ETS, do not allow sequestered carbon to be considered as equivalent to a reduction in greenhouse warming emissions. This is a mistake that will need to be rectified. It make more sense to use agricultural land to make biochar and biogases/bioliquids than to burn the biomass in power stations. Power stations burning wood benefit from buying fewer emissions certificates and from the renewable energy subsidy, but there is no comparable benefit from storing carbon in the soil. This is an anomaly that should be removed.

The Pre-Budget review in early October disappointed green activists. Environmental measures formed a small fraction of the government’s initiatives. It doesn’t look as though Alistair Darling sees climate change as one of the priorities of this administration. But there were two important commitments: a revision to Air Passenger Duty (APD) and (via BERR) a competition to run a commercial-scale carbon capture project.
Both the Conservative and Lib Dem parties have produced position papers on climate change in the last few weeks. The Conservative document is over 500 pages long but contains very few specific proposals. To be harsh, it is little more than a prolonged agonising over whether the climate change problem can be addressed using conventional free-market mechanisms. The Lib Dem paper is a tenth of the length but does contain the outlines of a coherent set of policies.
In early September, researchers from the Tyndall Centre in the UK put out a report that said that incorporation of the airline industry into the Emissions Trading Scheme (ETS) will not provide significant incentive to cut emissions. The big polluters today are paying about €20 per tonne for their emissions. When aviation joins the scheme in 2012, this price would add about €5 for a flight to Barcelona. Tyndall argues that the EU and national governments cannot escape the conclusion that the ETS is not enough and that aviation must be constrained by other fiscal or legislative measures as well as by inclusion in the carbon tax net.
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