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Biofuels: Benefits and risks for developing countries

18 December 2007

BANGLADESH - Global production of biofuels is growing steadily and will continue to do so. Biofuels offer greater energy security, reduced emissions of greenhouse gases and particulates, rural development, better vehicle performance, and reduced demand for petroleum.

But they also raise pressing issues that need addressing before biofuels become widespread around the world, and in Africa in particular. These relate to land requirements and availability, policies, knowledge, standards, awareness, participation and investment.

Africa has relatively little biofuel development, except in South Africa, and more information on the few activities that are underway is urgently needed.

Across the world, but particularly in Africa, policymakers and researchers need to:

  • better understand how biomass production affects food production; and

  • identify suitable feedstock for biofuels, and research the most appropriate production and processing procedures, environmental impacts and the potential for domestic, regional and international trade in biofuels.

This article focuses on liquid biofuels - bioethanol and biodiesel. Of the two, bioethanol is currently the bigger industry. Of the estimated 130 million barrels of biofuels produced worldwide in 2004, 95 million barrels came from bioethanol.

Commercial bioethanol is mostly produced from sugarcane, sugar beet and corn. Other sources are sweet stem sorghum and cassava, and cellulosic material such as grasses, trees and various waste products from crops, wood processing and municipal solid wastes.

Bioethanol can be blended with conventional fuels to at least 10 per cent (10 per cent ethanol: 90 per cent gasoline). Kenya used blends of 20 per cent alcohol in the 1990s without significant affecting engine performance. And if engines are modified, a much higher percentage of bioethanol can be used.

In 2003, global production was double the level of a decade earlier, and from 2000 to 2005, production increased from 4.6 billion to 12.2 billion gallons. Brazil and the United States are world leaders in using ethanol.

Biodiesel, a light to dark yellow liquid, is biodegradable, non-toxic and has significantly fewer emissions than petroleum-based diesel. It is practically immiscible with water, has a high boiling point and low vapour pressure. Biodiesel is produced from a wide range of feedstock, including fresh soybean oil, mustard seed oil, waste vegetable oil, palm oil, rapeseed, sunflower, soybean and jatropha, copra, palm, groundnut and cotton seed.

With a viscosity similar to petro-diesel, it can be used in diesel engines (cars, trucks, buses, construction equipment), jet engines, and heating and electricity generating systems. It blends easily with petro-diesel and can be used as an additive to ultra-low sulphur diesel to increase lubricity.

Nearly all diesel-powered equipment can use blends of up to 20 per cent biodiesel, and many engines can use higher-level blends or even pure biodiesel with little or no modification. Most storage and distribution equipment take lower-level blends, but need special handling for higher-level blends.

Biodiesel use and production has been growing fast in the face of rising petroleum costs, and because of government tax subsidies. From a small base of 251 million gallons in 2000, production climbed to an estimated 790 million gallons in 2005.

Biofuels offer many benefits. By reducing demand for petroleum, biofuels could make energy supply more secure. Their use would also reduce import bills for energy-deficient countries and offer improved balance of trade and balance of payments. All these developments would unfreeze scarce resources for other pressing needs.

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Source: The New nation


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