The RSPB, Friends of the Earth and Greenpeace have said that the Government’s own data suggests using trees would produce nearly 50 per cent more greenhouse gas emissions than coal – undermining the very problem they are expected to help solve.
Their report, called Dirtier than coal?, follows moves by coal power stations including Drax and Eggborough to switch from burning coal to wood.
Councillors in Hull last week approved plans for a £130m “green electricity” biomass plant, which will burn 250,000 tonnes of wood shipped from abroad. Developers Real Ventures say they will use pelleted virgin wood from the residues of sustainable commercial forestry operations and insist they have to satisfy “very strict” sustainability requirements.
And Drax, which is switching three of its six boilers to biomass, said it was “absurd” to suggest that using sustainable biomass was dirtier than fossil fuels.
But Harry Huyton, the RSPB’s head of climate policy, said subsidies do not distinguish between whole trees and debris left after trees were felled.
He said: “You can say you have imported a load of wood from South Africa as wood pellets and that would be enough to claim the subsidy. The certification doesn’t pay any attention to whether the wood is from a tree trunk or branch. If [the industry] is so certain that they are never going to burn a whole tree why won’t they agree to that as a requirement? They are all objecting because they say that will put too much cost on them.
“I regret but we can’t take these schemes on trust. We need really tight and independently accredited standards.”
Environmentalists, who are calling for the Government to exclude the burning of whole trees from subsidies, are also concerned that the rush for timber to burn will make what Mr Huyton described as “a pretty desperate situation for the world’s forests” worse. Up to 30m tonnes of wood could be burned – six times the total UK harvest. It would also impact negatively on carbon emissions as it takes so long for trees to grow back.
He said: “When trees are burnt in power stations, CO2 comes out of the chimney, just like it does when you burn coal. The difference is that the wood is less energy dense and is wetter than coal, so it takes a lot more energy to harvest, transport, process, and finally burn it. The Government has justified burning trees in power stations by claiming the chimney emissions are offset by the carbon that the forest takes in when it re-grows after being harvested, but this is misleading. It can take decades, if not centuries for the trees to recapture that carbon.”
Drax said forest cover had been increasing in the US, Russia and Europe between 1990 and 2010 – areas where most of the biomass used in the UK comes from.
A spokesman added: “This report misses the key points that most of the biomass used in electricity generation comes from the wood left over once other industries, for example furniture and paper, have taken their share, that managed forests absorb far more carbon than under-managed forests and that, provided bioenergy comes from sustainably managed forests where growth is in excess of harvest, there is no ‘carbon debt’, not even in the short term.”
Gaynor Hartnell, of the Renewable Energy Association, said there was plenty of spare capacity in North America with the decline in newsprint. She said: “A lot of these woodlands are crying out for a new market, they use a lot less newsprint now we have computers and Kindles.”
Speaking last week John Gallimore, from Real Ventures, said: “The Government have issued very strict sustainability requirements for biomass fuel. If we don’t comply then we won’t be able to claim our renewable obligation certificates and that would have a serious impact on the project.”