February 20, 2008. Copyright 2008, Graphic News. All rights reserved

Can biofuels support our love affair with the motorcar?
By Mark Rutter

LONDON, February 20, Graphic News:  With transport emissions a significant and increasing source of greenhouse gases, governments around the world are looking to introduce policies to stem the flow from exhausts. One popular solution is to replace fossil fuels with biofuels -- fuels made from crops. As the carbon dioxide given off during the burning of biofuels is equivalent to that absorbed from the atmosphere during the growth of the crop, there is no net output. However, many scientists and environmentalists now fear that the widespread introduction of biofuels could throw up greater problems than those it was designed to solve.
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The two main biofuels available are biodiesel and bioethanol. Biodiesel is derived from oils in crops such as rapeseed and palm, while bioethanol is made from sugary or starchy plants, typically sugarcane, sugar beet, maize, and cereals like wheat and barley. As almost all of the biofuel produced worldwide comes from food crops, there are obvious concerns over the impacts on global food prices and availability.
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Potentially harmful effects on the environment are also becoming apparent. Replacing grassland and forests with large swathes of a single crop could undoubtedly damage biodiversity by decreasing the variety of plant and animal species present. More intensive agriculture would require extensive irrigation, putting pressure on water resources in many areas. A greater demand for fertiliser application might impact in many ways, including increasing emissions of nitrous oxide -- a potent greenhouse gas -- from soils. The energy-intensive fertiliser manufacturing process would itself give rise to additional emissions of greenhouse gases. Further emissions would arise through burning fossil fuels during the cultivation, transport and processing of the plant material used for biofuel production.
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Perhaps the biggest concern is the greenhouse gases given off when natural habitats, especially tropical forests, are destroyed to grow biofuel crops. Several recent studies published in the journal Science have shown that large volumes of carbon dioxide stored in plants and soils are released during burning or clearing land. This creates an initial Òcarbon debtÓ, which requires many years cultivating biofuel crops on that land to offset. In the worst case -- biodiesel produced from palm grown on former rainforest peatland -- this would take around 423 years.
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What seems obvious now did not stop governments from rushing into providing tax subsidies and setting production targets to encourage a market for biofuels. The EU originally set a target of five percent market share by 2010 for its member countries. However, plans for a 10 percent target by 2020 are now under review due to question marks over the environmental benefits of biofuels.
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So where next for biofuels? Environmental standards are slowly being developed. These would require manufacturers to report on the environmental credentials of their products. Second-generation sources of biofuels -- e.g. wheat straw and woody plants -- are promising. They allow the whole of the plant to be used, have lower input requirements and can be grown on land not suitable for conventional agriculture. However, it will be up to 10 years before the technologies required are ready for commercial production.
/ENDS