From The Economist, “Wood, The fuel of the future“:
WHICH source of renewable energy is most important to the European Union? Solar power, perhaps? (Europe has three-quarters of the world’s total installed capacity of solar photovoltaic energy.) Or wind? (Germany trebled its wind-power capacity in the past decade.) The answer is neither. By far the largest so-called renewable fuel used in Europe is wood.
In its various forms, from sticks to pellets to sawdust, wood (or to use its fashionable name, biomass) accounts for about half of Europe’s renewable-energy consumption. In some countries, such as Poland and Finland, wood meets more than 80% of renewable-energy demand. Even in Germany, home of the Energiewende (energy transformation) which has poured huge subsidies into wind and solar power, 38% of non-fossil fuel consumption comes from the stuff. After years in which European governments have boasted about their high-tech, low-carbon energy revolution, the main beneficiary seems to be the favoured fuel of pre-industrial societies.
Also note, “because wood can be used in coal-fired power stations that might otherwise have been shut down under new environmental standards, it is extremely popular with power companies.”
But if subsidising biomass energy were an efficient way to cut carbon emissions, perhaps this collateral damage might be written off as an unfortunate consequence of a policy that was beneficial overall. So is it efficient? No.
Wood produces carbon twice over: once in the power station, once in the supply chain. The process of making pellets out of wood involves grinding it up, turning it into a dough and putting it under pressure. That, plus the shipping, requires energy and produces carbon: 200kg of CO2 for the amount of wood needed to provide 1MWh of electricity.
This decreases the amount of carbon saved by switching to wood, thus increasing the price of the savings. Given the subsidy of £45 per MWh, says Mr Vetter, it costs £225 to save one tonne of CO2 by switching from gas to wood. And that assumes the rest of the process (in the power station) is carbon neutral. It probably isn’t.
And there’s more, so read the whole thing, but you get the idea. A real case study in unintended consequences.