Biofuels: in search of green gold
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CTA. 2006. Biofuels: in search of green gold. Spore 123. CTA, Wageningen, The Netherlands.
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Soaring oil prices have rekindled an interest in plant-based biofuels. Sugarcane, cassava, sorghum or jatropha: in ACP countries, testing is forging full speed ahead to find the best source...
Soaring oil prices have rekindled an interest in plant-based biofuels. Sugarcane, cassava, sorghum or jatropha: in ACP countries, testing is forging full speed ahead to find the best source. Green petroleum? It sounds like a contradiction in terms. Yet biofuels are bona fide energy sources fuel made from biomass, vegetable or animal residues, as well as from plants grown expressly for the purpose. Biofuels have similar properties to petroleum and can be used in either diesel or petrol powered engines. In theory therefore, they could substitute petroleum altogether, solving the dual problems of high costs and pollution. The idea has been floated ever since the two oil crises of the 1970s. A number of countries did not wait for the most recent price hike to explore other energy sources. In Brazil, all vehicles run on a mixture using at least 25% ethanol derived from sugarcane. One of the earliest consumers of green fuels, Brazil now produces more than 12 bn l of biofuels per year, close to one-third of the world output, which is estimated at over 35 bn l. Brazilian bioethanol costs US$25 a barrel, less than half the price of black petroleum. In South Africa, industrial processes for producing innovative fuels based on coal, natural gas and especially biomass were developed under apartheid, in response to the oil embargo. Ethanol is currently the main biofuel produced by the Energy Development Corporation, which buys surplus maize from farmers for processing. Three million tonnes of maize produce 1.26 bn l of fuel, the equivalent of 12% of South Africa s energy needs. The country also uses sugarcane and sorghum to make biofuel. Green or black gold At the other end of the spectrum, a number of African countries have seen their fuel bills soar. Among them are several oil producing nations that export crude oil but need to import refined petroleum. A case in point is Nigeria (producing around 2 million barrels of crude oil per day) which relies on sales of hydrocarbons for 90% of its foreign earnings. The green fuel option seems all the more appealing given the limited quantities of fossil fuels left on the planet. Reserves are estimated at between 140 Gt (giga tonnes or billion tonnes, the equivalent of 1,050 Gb or gigabarrels) according to the Oil and Gas Journal and 160 Gt (1,200 Gb) according to the US Geological Survey. If current production and consumption rates continue, global oil reserves will be exhausted in less than 65 years, predicts the United Nations Conference on Trade and Development (UNCTAD). Bioethanol and biodiesel Bioethanol is a fuel mainly obtained by fermenting sugars contained in certain plants and by distilling the starch contained in their roots. It can be mixed with petrol in proportions of between 5 and 85%. Biodiesel or diester is made from vegetable oil or animal fat (from animal residues) transformed using a chemical process called transesterification. It can be used on its own to power engines, or mixed with petroleum diesel. Since 1997, most countries under the terms of the Kyoto Protocol have, in any case, committed to reducing their emissions of greenhouse gases by at least 5% below 1990 levels with a deadline set at between 2008 and 2012. Unlike fossil fuels, which release carbons previously stored underground into the atmosphere, biofuels release carbons derived from the atmosphere, which, once burned, simply return to their place of origin. One major drawback is that the raw materials used to make biofuels are still very expensive to grow, collect and transform for countries new to the process. Researchers at the French Agricultural Research Centre for International Development (CIRAD) calculate that green petroleum will only be a viable alternative to classic petroleum if prices for the latter remain very high (at least US$70-80/barrel). Another slight snag based on 2004 consumption levels, you would need to cultivate six times the Earth s surface in order to have enough biofuel to replace fossil fuels! An energy opportunity? The EC has pledged to ensure that measures for ACP Sugar Protocol countries affected by the EU sugar reform can be used to support the development of bioethanol production . The EU has announced it will cut by 36% over 4 years the price paid for sugar from ACP countries, previously protected by the Sugar Protocol (see Spore 122). Aware that change is inevitable, some major sugar-producing ACP countries have already begun diversifying from their time-honoured crop. Mauritius has started converting its sugar industry and moved into ethanol production. The island also has 10 mixed power plants which produce sufficient energy to meet 40% of the electricity requirements using bagasse, a by-product of sugarcane (see Spore 116). In Fiji, joint studies carried out by the University of the South Pacific and experts from Mauritius have concluded that this other small ACP island state has similar potential. Mauritius revs up on ethanol At a time when oil prices are rocketing and sugar prices are plummeting, Mauritius is developing an interesting middle ground. Having launched the production of crude ethanol from sugarcane 3 years ago, Alcodis, the island s premier manufacturer, has begun making dehydrated ethanol. The initiative, worth a total of 10.5 million, has been developed through a partnership between two local companies, Roland Maurel and Mauvilac Ltd, and the Spanish group Tradhol Internacional, a world leader in the distribution of ethanol, and especially active in Africa and the Caribbean. Dehydrated ethanol is used as a biofuel, as well as in pharmacology, and in the cosmetics and chemical industries. Alcodis is planning to start exporting to the EU by the end of 2006. In the Caribbean, St Kitts, which closed down its sugar industry in July 2005, is studying proposals from several Norwegian and US companies to process part of its sugarcane output. The initiative should prove viable for areas under sugarcane cultivation of 2,500 ha upwards. Guyana is showing similar interest and signed a partnership deal with Brazil in October 2005. Jamaica is planning to follow the same route. A variety of other initiatives aim to produce extra income for small-scale farmers and diversify energy supplies in the public transport and electricity sectors. Nigeria has chosen to produce ethanol from cassava (see Spore 120). A law introduced this year allows 10% of biofuel to be mixed with petrol, thus reducing the fuel bill and pollution levels in a single stroke. In the first instance, this green oil will be imported by Brazil. Another promising alternative energy source is sorghum, which needs little fertiliser and is resistant to drought. The Dominican Republic will shortly be unveiling a unit for producing sorghum-based ethanol, linked to a 20 MW electrical plant. Growing interest is also being shown in using vegetable oils to power diesel engines for agriculture, produce electricity and fuel transport vehicles. In Malawi, farmers are being encouraged to leave tobacco cultivation and turn to growing Jatropha, also known as the physic nut (Jatropha curcas), a member of the Euphorbiaceae family. It is drought resistant, easy to maintain and shunned by animals due to its unpleasant odour. More than a million of these plants are currently believed to grow in the country. In Mali, PNVEP, a national programme aimed at exploiting the energy potential of Jatropha, is planning to use the plant to power rural electrification and transport vehicles. The goal: to provide electricity for 350 villages in the regions of Kayes, Koulikoro, Ségou and Sikasso, between now and 2008. All over the world, trials are being carried out on a range of oleaginous plants jojoba, coconut (see Spore 105), oil palm, cotton, sunflower, groundnut, soya, rape, flax which hold out hope as low-cost suppliers of biofuels. However, not everyone agrees on the merits of large-scale biofuel production. Critics argue that it could bring more pressure to bear on ecologically sensitive areas, have adverse effects on soil fertility, lead to a drop in the availability and quality of water supplies and a rise in the use of fertilisers and pesticides. And while the combustion of these so-called biofuels generally produces less carbon monoxide, sulphur dioxide and particulates, it also releases greater quantities of other toxic compounds. Assessments of the global energy used to produce these biofuels are equally controversial. A study published in July 2005 by researchers at the University of Berkeley (USA) claimed that producing soya-based biodiesel consumed 27% more energy than producing petroleum. Competition in ACP countries between energy crops and food crops is also the subject of lively debate. The International Energy Agency (IEA) observes that if production of alternative fuels were to increase significantly, the demand on land would be considerable. Growing consumption levels of green petroleum could modify the way land is used and lead to a dramatic rise in food prices in the South. Towards clean development There is a risk of an imbalance developing between countries where biofuels can be produced at low cost and those where the demand is rising the fastest. In any event, it should soon be possible to lower the cost price of biofuels thanks to biorefining (where every part of the plant is used) and by using so-called second generation biofuels based on lignocellulosic material such as straw and timber residue. In June 2005, UNCTAD launched its Biofuels Initiative. A group of international experts was formed to help developing countries benefit from increased production, use and trade in biofuels. The initiative aims to generate new investments through the Clean Development Mechanism. The Doha declaration, adopted by the World Trade Organization (WTO) in 2001, takes a similar approach. It encourages negotiations on the reduction or elimination of tariff and non-tariff barriers to environmental goods and services . Biofuels derived from sustainable agricultural practices could therefore enable low and medium-income ACP countries to create substantial export markets. It remains to be seen if biofuels will really fuel a fairer distribution of wealth on the planet.
- CTA Spore (English)