The great biofuel delusion
News 24, 24 November 2010
Have you ever thought about what you are going to put in your car's tank when petrol becomes prohibitively expensive as the world’s oil supplies start to dry up? And have you ever worried about the fact that the greenhouse gasses emitted by the car you drive every day make a massive contribution to climate change?
"No worries," you say. "We'll just convert all of our cars to run on biofuels!"
Indeed, biodiesel and bioethanol are often portrayed as the green and sustainable answer to our transport woes in an oil-free future. But how viable and eco-friendly are such biofuels really?
A wide variety of plant materials, from maize and soyabeans to sugar cane and various grasses can be converted into biofuels. They can either be mixed with conventional diesel or petrol, or (with relatively minor modifications to the car) used in undiluted form to power a combustion engine. Their promise lies in the fact that the raw materials can be grown commercially like any other agricultural crop and that they should, in theory, be carbon neutral, absorbing as much CO2 during growth as they emit when burned as fuel.
Biofuels under scrutiny
Many countries have started to promote the use of biofuels as part of their commitment to reducing greenhouses gas (GHG) emissions and combating climate change. Member states of the EU, for instance, are legally required to derive 10% of their transport fuels from renewable sources that cut GHG emissions compared to fossil fuels by 2020. South Africa’s draft biofuel strategy calls for a mandatory 4.5% biofuel component in road transport fuel by 2013.
In recent years, however, biofuels have come under increasing scrutiny and overall prospects are not looking good. Since most biofuels are currently made from food crops including maize and vegetable oils, it is now widely acknowledged that they have contributed significantly to worldwide increases in food prices.
In countries like Indonesia and Malaysia, huge new palm oil plantations established specifically for biodiesel production have led to deforestation and the draining of peatlands, destroying valuable ecosystems and biodiversity and releasing large amounts of GHGs. Experiments with Jatropha, a promising non-food tree crop have experienced low-yields and crop failures in various countries.
Studies have shown that there simply isn't enough arable land to quench our fuel-thirst on biofuels. If current US and EU biofuel targets were to be met domestically, almost all of the soy and maize grown in North America would have to be used and Europe would be left with only about a third of its farmland to grow food on.
Proponents argue that compared to fossil fuels, biofuels reduce GHG emission by as much as 50%, but these numbers don't stand up to scrutiny. A 2007 study suggests that because of their extensive use of fertilisers that emit nitrous oxide, a potent greenhouse gas, European farmers who grow rapeseed for biodiesel production would do better if they planted trees and let regular diesel be used instead.
In the USA, maize-based bioethanol has been shown to require as much or more energy to produce than it releases when burnt and may actually cause GHG emissions to almost double instead of reducing them. Recent research suggests that the same is true for algae, another promising biofuel feedstock.
A dead end
Earlier this month, a study commissioned by the Institute for European Environmental Policy estimated that in order to meet the EU’s 2020 biofuel targets, an additional 4.1 to 6.9 million hectares of land will have to be cultivated much of it in developing countries resulting in 80 to 167% more GHG emissions than if the demand was met through fossil fuels.
The verdict? Biofuels are a dead end.
While they can provide a limited amount of truly green and sustainable transport fuel, biofuels will never be able to satisfy our current fossil fuel addiction. Electric vehicles powered by renewable solar and wind energy, once they are widely available, are a much better bet. But ultimately, I suspect, we’re asking the wrong question.
We shouldn't be obsessed about how to replace our profligate consumption of one resource with that of another, but with how we can drastically reduce the use of such resources altogether and live more sustainably.
- Andreas has a PhD in geochemistry and manages Lobby Books, the independent book shop at Idasa’s Cape Town Democracy Centre. Follow him on Twitter: @Andreas_Spath