28 October 2012

Biofuels – Not the Solution


It didn’t take long for biofuels to go from saint to sinner destroying early hopes that they offered a low carbon means of meeting our energy requirements. This idea was quickly replaced with the realisation that a full life cycle analysis showed few offered any real benefit over fossil fuels and many produced even greater carbon emissions once land use changes were accounted for.

Unfortunately the political process moves a lot more slowly than scientific knowledge. The analysis that biofuels offered no environmental benefit has not stopped the US government from subsidising the growth of refineries to turn corn into ethanol, or the EU from mandating that transport fuels should have a steadily increasing biofuel content.

Finally though the message seems to be getting through, and leaked documents have indicated that the EU is planning on reducing its 2020 target for the percentage of biofuel in transport fuels from 10% to 5%. Critically it appears to be the fact that these fuels use food crops which has driven the change of policy. In a world where global food production has been lower than consumption in six of the last eleven years and reserves have shrunk from 107 days of consumption 10 years ago to just 74 days now, politicians are finally acknowledging the absurdity of turning food into fuel.

In America too they are debating the logic of a policy which decreed that the ethanol content in gasoline should rise each year and which had led to around half the US corn crop being used to make fuel. In a year when the US maize crop has been devastated by a heatwave, highlighting the vulnerability of our food production to the increasing impacts of climate change, this policy has contributed to food prices reaching record highs with consequences for the number of people going hungry around the world.

But just as we are getting to grips with the absurdity of using grains to make fuel, so here in the UK we are seeing a surge in applications for biomass power stations to generate electricity; typically these will burn wood or palm oil. Drax, the country’s largest coal fired power station has long co-fired a limited amount of biomass mostly sourced locally. Now though it hopes to convert three of its six generating units to run on biomass. This would involve a major increase in the amount of biomass required implying either substantial imports or the conversion of much local land to produce the required volumes. Meanwhile in Tilbury RWE have applied for planning permission to use a former coal station to burn millions of tonnes of timber every year, most probably from the USA and Canada – you can help object to this here.
Elsewhere around the country there has been a surge of applications for power stations which are likely to run on imported palm oil, contributing to the rapid destruction of rainforests and peatlands in Indonesia and other Asian countries. To add insult to injury most of these biomass power stations will only generate electricity, and will dump the heat generated in the firing. This is a very inefficient use of the total potential energy available; it’s like paying for something which costs £4 with a £10 note and then throwing the change down a drain. We have to realise we have limited resources on this planet and we must use them all as efficiently as possible.

Why is this happening now? Because our government is subsidising biomass as a low carbon power source. The premise is that burning wood is carbon neutral because the CO2 was only recently locked up by the tree growth and replanting will recapture the CO2 again. Even the most cursory of thought processes though will tell you that there is still a significant time-lag involved of 40+ years before any new tree has locked away an equivalent amount to that being released in a few minutes of combustion. This is time we don’t have. Once again the thinking here is all wrong and an EU analysis has concluded that “the use of trees from forests for bioenergy purposes would cause an actual increase in greenhouse gas emissions compared to fossil fuels in the short term”. So not just not carbon neutral, but actually worse than fossil fuels.

We need to tackle the source of this problem – the subsidy - now before committing ourselves to building more infrastructure which will actually harm the environment rather than benefit it. Subsidising real renewables, such as wind, solar, tidal and wave power will help develop these industries and decarbonise our energy industry in the longer term. Subsidising biomass will do no such thing.

1 comment:

  1. Thanks for my mini environment update - this subject so confused me with the back and forth debate.

    ReplyDelete