Matt Ridley: Cutting Down Trees Is A Fuelish Craze

  • Date: 17/11/12
  • Matt Ridley, The Times

Windpower gets everyone annoyed but when it comes to renewable energy, biomass is an even crazier idea. If you are worried about carbon dioxide, why not choose a technology that works rather than one that doesn’t?

Never has an undercover video sting delighted its victims more. A Greenpeace investigation has caught some Tory MPs scheming to save the countryside from wind farms and cut ordinary people’s energy bills while Lib Dems, Guardian writers and Greenpeace activists defend subsidies for fat-cat capitalists and rich landowners with their snouts in the wind-farm trough. Said Tories will be inundated with fan mail.

Yet, for all the furore wind power generates, the bald truth is that it is an irrelevance. Its contribution to cutting carbon dioxide emissions is at best a statistical asterisk. As Professor Gordon Hughes, of the University of Edinburgh, has shown, if wind ever does make a significant contribution to energy capacity its intermittent nature would require a wasteful “spinning” back-up of gas-fired power stations, so it would still make no difference to emissions or might make them worse.

And wind is not the worst of the renewables. By far the largest source of renewable energy is bio-energy (ie vegetable matter turned into solid, liquid or gaseous fuel), which is expanding fast and doing less than nothing to cut emissions. Even the big three green multinationals — Greenpeace, Friends of the Earth and WWF — have come out against biofuels.

Last year, despite a decade of subsidies and the desecration of quite a bit of countryside, 96.8 per cent of our total energy still came from fossil fuels and nuclear. The rest came from bio-energy (2.6 per cent), leaving a derisory 0.6 per cent from wind, hydro, solar, wave, tidal and geothermal put together. It is therefore a little-known fact that 77 per cent of Britain’s renewable energy involves burning something. (All these figures for 2011 are from the Department of Energy).

And there is nothing carbon-saving about bio-energy. Take wood, a more carbon-rich fuel even than coal. As the environmental scientist Jesse Ausubel, of Rockefeller University in New York, has shown, when you burn wood more carbon dioxide is emitted than from coal for the same amount of energy.

Yet Britain is dashing to replace coal with wood. Many coal plants are being subsidised to switch to biomass. Drax in North Yorkshire, the country’s largest power station, is switching partly from coal to biomass while Eggborough, in the same county, will convert fully to become Britain’s leading renewable power plant.

By 2030, according to current plans, the UK will be burning five times the maximum timber harvest that Britain could conceivably produce. So most of it will be — and already is being — imported in the form of pellets, lumber, olive pips and peanut husks. Some will come from tropical rain forests, or will raise prices enough to encourage the felling of more rain forests.(Remember, it is fossil fuels we have to thank for reversing the great deforestation of these islands in the Middle Ages — Britain now has three times as much forest as in the 1800s.) Although today’s dash back to biomass is driven by European carbon-emissions reduction targets, not an ounce of carbon will be saved. Its champions argue that because trees grow in place of those chopped down, wood is almost carbon-neutral, whereas fossil fuels are not. But, as Professor Helmut Haberl, of the University of Klagenfurt in Austria, has pointed out, this makes no sense. Carbon is carbon. Land grows plants whether it is used for biofuel or not. Chopping down a tree to burn its wood oxidises the tree’s carbon atoms decades before they would be released by decay. It could take 200 years to break even in carbon terms by planting new trees.So it is a ludicrous myth that biomass cuts carbon emissions.

Of course, the biomass dash is excellent news for woodland owners (such as me) who are now incentivised to thin and fell woodlands at a faster rate in the hope of making, or more likely losing less, money on the management of woods. It is less good news for the coal industry, in which I also have an indirect interest. But it’s the least fun for those of us who pay electricity bills, where the subsidy is artfully concealed.

The Renewable Heat Initiative, encouraging us to heat our homes at public expense with wood rather than gas, is even worse. Wood is much higher in carbon than gas, so if you switch from gas heating to wood you generate more CO2 emissions; not to mention depriving beetles of rotting logs and woodpeckers of beetles. Lorries will soon be delivering 25,000 tonnes of wood chips a year to Heathrow’s Terminal 2. Compared with gas, this is madness in economic, ecological and traffic terms.

Growing crops to be turned into biofuel makes even less sense. For a start, the diesel and fertiliser come from fossil fuels, so some of the world’s biofuel crops are not carbon neutral when harvested, let alone when burnt. Those that are, such as Brazilian sugar-cane ethanol, rely on cheap labour. But it’s worse than that. Biofuels are displacing food crops, which raises prices and in turn encourages forest clearance to grow more crops. A Leicester University study found that such “indirect land use changes” might take 423 years to pay back the up-front carbon debt.

Copying Germany, Britain’s farmers are now being enticed by subsidies to install anaerobic digesters. Contrary to popular myth these digest, not manure, but raw crops, mainly maize. Again this makes no sense.

Britain’s dash for renewable energy is already costing its hard-pressed economy tens of billions of pounds a year — and rising. Yet it will not make a dent in carbon dioxide emissions, let alone enough to affect climate.

Meanwhile, across the Atlantic, huge cuts in carbon dioxide emissions are happening. America is now producing less CO2 than it did in the early 1990s, and 30 per cent less per head than it did in in 1973. It has done this while cutting rather than raising energy bills and generating revenues rather than consuming subsidies. The reason? Cheap gas replacing coal, thanks to fracking. If you are worried about carbon dioxide, why not choose a technology that works rather than one that doesn’t?

Matt Ridley is the author of The Rational Optimist: How Prosperity Evolves. He is a member of the GWPF’s Academic Advisory Council 

The Times, 17 November 2012