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Burning wood is the worst thing you can do for carbon dioxide emissions

I have an opinion article in The Times today:

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?

By Matt Ridley | Tagged:  rational-optimist  the-times