Contributor to www.afsl.org.uk
An alternative to fossil fuel
We all know that driving is a major contributor to global warming - for the average UK citizen 19% of their carbon footprint comes from car use. But what if we could power our vehicles with something other than fossil fuels? This is the tempting prospect of ‘biofuels’ - fuels derived from organic matter.
Bioethanol, used as a substitute for petrol, is usually made from sugar beat or corn, whilst bio-diesel is produced from various plant oils. Brazil has long used ethanol extensively, with half of its sugar cane crop going into transport fuel. Most cars can burn petrol blended with up to 10% bioethanol without any modifications to the engine, and some new cars can burn pure bioethanol. Biodiesel can be used in place of normal diesel without modification to the engine.
The hope is that both offer the potential of cutting greenhouse gas emissions quickly with minimal modification to existing vehicles and fuel infrastructure. A recent study conducted by Sheffield Hallam University suggested CO2 savings in the region of 70% for biodiesel compared to petroleum diesel.[1] In the hope of capitalising on reduced emissions European Union law has set a target that by 2010 all vehicle fuels must be blended with 5.75% biofuels. According to a recent report by the Worldwatch Institute biofuels can significantly reduce global dependence on oil - and biofuel production has doubled since 2001.
So why has well-known environmental campaigner George Monbiot called biofuels “the most destructive crop on earth”?[2]
Do the numbers add up?
In the US, with federal subsidies for ethanol production, at least 39 new ethanol plants will be completed over the next year, adding 30% to current production and pushing the US passed Brazil as the world’s largest ethanol producer.[3] But with world biofuel production at 670,000 barrels per day, that is only equivalent to about 1 % of the global transport fuel market.[4]
Brazil produces 10% of its entire fuel consumption from just 3% of its agricultural land – an attractive prospect. But Brazilians drive far less than Europeans and Americans, their crop yields are higher due to climate and soil fertility, and their population density is lower than in the West.[5] The Worldwatch study estimates that for the US to achieve that 10% target would require that 30% of its agricultural land be dedicated to biofuels - and for Europe a wholly unrealistic 72% would be needed.
Ethanol Gold Rush
The reality is that 15% of the US’s corn crop is allocated toward ethanol production, and this has already caused corn prices to rise 30%, causing an across-the-board increase in food prices[6]. Using crops normally grown for the food for fuel instead creates massive increases in demand and hence large price increases. For the US to replace the oil it imports from the Persian Gulf with corn-based ethanol would take at least half the nation’s farmland.[7] Some experts in the US are arguing that at the current pace of development, ethanol production could strain food supplies and force the use of marginal farmland set aside for conservation. It takes four to five gallons of water to produce one gallon of ethanol and ethanol production threatens to deplete groundwater aquifers in the US Midwest, which also supply agriculture.
Despite these many problems it is not even clear that ethanol will actually reduce carbon emissions. Fossil fuels are used at every stage of the process from growing corn with petroleum-based fertilizers, herbicides and pesticides, to oil to run tractors, to natural gas used in the distillation process to turn corn into ethanol through to transporting the ethanol to blending facilities by truck and rail. Several studies show that obtaining ethanol from corn actually consumes more energy than ethanol provides!
Lester Brown has described the boom in bioethanol as a competition between the 800 million people in the world who own cars with the 3 billion people who struggle to feed themselves on less than $2 a day. The corn required to fill an SUV tank with bioethanol just once could feed one person for an entire year[8].
Palm Oil Controversy
In Europe there is no way to meet the modest 2010 target for blending fossil fuels with biofuel utilising crops from European land, so the target will be met with massive imports of vegetable oils.
Importing vegetable oils might sound benign compared to drilling more oil wells – but the reality is far from it, involving the destruction of virgin rainforests and the potential extinction of the orang-utans that live in them. Palm oil produces significantly better yields of biofuel per hectare than other crops and so is the crop of choice for an international biodiesel market. It is grown mainly in rainforest areas in South East Asia and development of new plantations has resulted in the destruction of large areas of virgin forests with high conservation value and rich biodiversity. Moreover the destruction is occurring at a time when it is essential that the world preserves rainforest or face climate chaos.
Malaysia and Indonesia, which together dominate the world market for palm oil, announced a joint plan in July to set aside 40% of their palm oil output for biodiesel production.[9]
Palm oil is also a common ingredient in processed food and cosmetic products and in the UK Friends of the Earth and Co-operative Insurance have worked hard to persuade all the biggest UK food retailers to join the Roundtable for Sustainable Palm Oil, which is seeking to establish standards for the sustainable production of the oil. The use of palm oil as a replacement for crude oil is unsustainable and will cause more problems than it solves. This is also the case for soy oil coming from farms in Brazil - where the Amazon rainforest is being cleared to make way for the expansion of huge fields growing soy.
Technology to the rescue?
Researchers are discovering ways to produce bioethanol without using food crops, and instead focusing on converting cellulose-rich organic matter into ethanol. Cellulose is the main structural component of all green plants and developing an efficient process to convert cellulose into ethanol could enable the use of non-food materials such as straw, crop residues like stalks, hardwood chips, even paper, cardboard and food waste. Switchgrass, a wild grass the grows in the US on land unsuitable for food crops has also been suggested as a feedstock and some suggest cellulosic ethanol could provide twice the yield of current corn ethanol[10].
As for biodiesel there are potential substitutes for environmentally damaging palm oil that look promising, such as Jatropha and microalgae, but more development of these is still needed.
One emerging technology even utilises algae to convert the CO2 produced by power plants into biofuel, creating a cycle that takes the carbon from the smokestack to the petrol tank before it enters the atmosphere[11].
Exciting though these technologies are they still cannot provide the immediate cuts in green house gas emissions needed if we are to tackle climate change - we simply cannot afford to wait in hope for a technological fix.
Sustainable Biofuels
This is not to say all biofuels is unsustainable - but we cannot simply replace an international market in oil with one in biofuels. Biofuels are not a panacea which enable ‘business as usual’ – the profligate use of energy and the careless waste of resources.
For example, Green Gold Biodiesel in Manchester, the first dedicated biodiesel garage in the UK, follows best practice in producing biodiesel using renewable feedstocks, and wherever possible used cooking oil. Utilising a resource that would otherwise be waste allows a far greater reduction in carbon dioxide emissions than for virgin oil The British Association for Biofuels and Oils estimates the volume of waste cooking oil in the UK at 100,000 tonnes a year[12] - but that is enough to meet only one 380th of our demand for road transport fuel[13].
Ultimately, it is not just the fuel that needs to change; it is the lifestyle that makes use of it.
[3] ALEXEI BARRIONUEVO “Boom in Ethanol Reshapes Economy of Heartland” New York Times June 25, 2006
[4] Biofuels for Transportation: Global Potential and Implications for Sustainable Agriculture and Energy in the 21st Century
[5] Fred Pearce “Fuels gold: Big risks of the biofuel revolution” New Scientist 25 September 2006
[6] “Ethanol production comes at a high price” Rutland Herald, September 10, 2006
[7] ALEXEI BARRIONUEVO “Boom in Ethanol Reshapes Economy of Heartland” New York Times June 25, 2006
[8] George Monbiot “Biodiesel enthusiasts have accidentally invented the most carbon-intensive fuel on earth” The Guardian 6th December 2005
[9] Fred Pearce “Fuels gold: Big risks of the biofuel revolution” New Scientist, 25 September 2006
[10] Fred Pearce “Fuels gold: Big risks of the biofuel revolution” New Scientist, 25 September 2006
[11] Phil Mckenna “Biofuel made from power plant CO2 “ New Scientist, 6 October 2006
[13] George Monbiot. “Biodiesel enthusiasts have accidentally invented the most carbon-intensive fuel on earth” The Guardian 6th December 2005
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