Renewable energy: Bonfire of the subsidies TO GO by the Domesday Book, the record of taxable lands produced for William the Conqueror in 1086, the manor of Drax, in the West Riding of Yorkshire, was not much of a place: six villagers, a priest and a value to its lord of a single pound. But it did have five leagues of woodland. Today Drax is home to one of the most impressive pieces of engineering in Britain, a power station with a value to its owners of £2.5 billion. But it does not have much woodland. And, given the way Europe's renewable-energy subsidies work, the appetites of that facility, and others around Europe, may mean that wood is in short supply in many places before long. In 2009 the European Union set itself the target of getting 20% of its energy from renewable sources. For all the fields and roofs covered with solar panels and the once-empty uplands enlivened by wind turbines, by far the biggest power source in the plans is biomass: wood, crop residues and other burnable recently living stuff. The EU's planners want to get 1,210 terawatt hours of energy from biomass in 2020, compared with 494TWh from wind. About 80% of that biomass energy would be used to heat things - wood-burning stoves and boilers are widely used in many European countries. But the 20% used to generate electricity would still equal all the energy expected from solar panels and offshore wind. With wind power not growing at the rate that planners want, biomass may be called on to do even more. The dash for biomass, though, has many problems (see article). As with wind and solar power, investment in biomass does not happen without subsidy; current plans to convert half of Drax's 4,000 megawatt capacity from coal to biomass depend on getting an extra £45 per megawatt hour from the government on top of what the electricity sells for. It also takes a lot of land to produce power with biomass. Generating 2,000MW of electricity from wood in a sustainable way requires a forest of some 6,600 square kilometres - which is more or less, as it happens, the area of the whole West Riding. Unlike wind and solar generators, biomass burners must buy fuel. This is already putting pressure on prices for other wood users, such as builders, cabinet-makers and, we should admit, magazines that are still printed on paper. It also increases reliance on imports - one of the things that renewables are often claimed to reduce. Worse, biomass-burning is nothing like as good a climate hedge as people tend to think. Biomass claims to be a "carbon neutral" way of generating power: although burning wood puts carbon dioxide into the atmosphere, growing replacement wood sucks that carbon dioxide back out. But the ideal of a biomass plantation that is harvested only at the rate at which it grows back is not always met. Even when it is, such plantations displace other ecosystems that would themselves have sucked down carbon. Processing and transporting the wood to the place where it is burned requires energy that may well come from non-renewable sources. According to the European Environment Agency, an EU body not involved in setting subsidies, some biomass programmes could end up emitting more carbon than the fossil fuels they are being subsidised to replace. The wood for the trees The underlying problem is the reverence accorded to renewable energy itself. Greens like it for various reasons: independence from fluctuating fuel prices, rural employment, sustainability, as well as low carbon emissions. But as the sorry state of biomass shows, not all renewable-energy technologies are good at achieving all those aims. Nor are all those aims worth spending scarce public money on. And those that are will often be amenable to more efficient support than is provided by broad, market-distorting subsidies. Moving to an ever-lower-carbon economy at a deliberate pace is a good idea. The best way to do it is to set a carbon tax and let the market decide the cheapest, cleanest answer while researching future alternatives. Some renewable technologies would play a big role in that. But those who pursue renewable energy as an end in itself fail to see the wood for the trees.