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| Sunday, 19 June 2005 |
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Features |  |
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Save the earth Powered by plants The diesel fuel in your car could one day come from plants rather than oil wells, according to chemists who have converted plant chemicals into useful hydrocarbons.
The easiest way to extract energy from plants is simply to burn them, and convert the heat to electricity. Although this is good for stationary power plants, it isn't ideal for cars. Electric cars have to be recharged frequently, which may make them unsuitable for long journeys. A better idea is to convert plant material into fuel that vehicles can use directly. This has been done with the fatty acids in vegetable oils, which make up a small part of plant material. But now researchers have found a way to create fuel from the carbohydrates that make up about 75 per cent of a plant's dried weight. The result is a much more efficient use of plant material, report James Dumesic, a chemist from University of Wisconsin, Madison, and his colleagues in Science. The plant-derived hydrocarbons are just like conventional diesel, notes Jens Rostrup-Nielsen of Haldor Topsoe, a chemical technology company based in Lyngby, Denmark, so they can be distributed through existing infrastructure. This makes the fuel easier to use than hydrogen, for example, which requires a different kind of pumping station and storage system. If all goes according to plan, Dumesic estimates that one could grow enough plants in the United States to power a significant percentage of the country's vehicles. Chain of fuels Carbohydrates have proven an expensive source of fuel in the past. Glucose, for example, can be fermented into ethanol and then added to gasoline. But this process is very inefficient, largely because of the energy it takes to boil ethanol away from water at the end of the fermentation. Dumesic's team reasoned that this energy-intensive process could be avoided if plant carbohydrates were converted directly to the long-chain hydrocarbons that make up diesel fuel. Because oil and water do not mix, these hydrocarbons float to the top of the reaction mixture, where they are easily siphoned off. The chemists first used a platinum catalyst to make carbohydrates containing five or six carbon atoms react with hydrogen gas: plant material provides both the carbs and the gas2. A magnesium-based catalyst then knits these molecules together to create the longer carbon chains required for diesel fuel. Adding more pressurised hydrogen, and removing any remaining oxygen atoms with a platinum catalyst, delivers the finished fuel. An escape valve for greenhouse gas
Out on the gusty plains of Saskatchewan, miles of new clean-energy wind turbines will eventually be joined by a familiar old ghost of electricity generation: a new coal-fired power plant. Such coal facilities are generally bad news for those worried about climate change. Fossil-fuel power plants produce about a third of all the heat-trapping man-made carbon dioxide released into the atmosphere. And the 1,300 new coal-fired plants expected to be built over the next quarter-century will pump an extra 145 billion tons out by 2030 - and much more over their 40 to 50-year life spans. But at least the Saskatchewan plant, slated to go on-line in 2013 about 110 miles south of Regina, will sport a newfangled escape valve. By designing in a few million dollars of extras - everything from extra ductwork and bigger boilers to extra open space right next to key areas of the plant - utility officials are creating one of the world's first 'capture ready' plants. The idea: If and when government regulation forces it, the plant will be ready to accommodate any future technology needed to capture CO2 from its exhaust and pump it permanently underground. "We're building a plant that will last for a number of decades, so it seems prudent to recognise that at some point during that time, carbon will have to be managed," says Rick Patrick, SaskPower's vice president of planning, environment, and regulatory affairs. "We think a capture-ready design will give us maximum flexibility for whatever comes at us." Saskatchewan's 'capture ready' idea seems most likely to appeal to Canada, the European nations, and other countries required to slash CO2 emissions under the Kyoto accord by 2012. But the idea has less traction in critical areas such as China, India, and the United States, where most new coal-fired power plants will be built, and where there is no immediate demand to reduce CO2. Critics on the left Even environmentalists are wary. Some see the capture-ready idea as another excuse for power companies to drag their heels on a far more advanced clean-coal technology called integrated gasification combined cycle or IGCC. "Building new coal-fired plants and betting on vague claims and future promises of technology at least a decade behind IGCC is a bad bet," says David Hawkins, director of the Natural Resources Defense Council's climate center. "We've got gasification plants capturing CO2 today." Still, he would not oppose capture-ready technology for any conventional coal power plant that's about to be built, calling it 'a reasonable backup.' For a 'negligible cost,' China could direct its power-plant developers to at least design their coal-fired plants so they could be cheaply retrofitted, says Jon Gibbins, an energy expert and senior lecturer at the Imperial College of London. "Certainly China is today facing a power shortage, so anything that distracts them even in a small degree from building plants is not seriously considered," Dr. Gibbins says. "Still, I think there are several reasons China might just decide to do it. The Chinese government might order its plants to be built capture ready. And the other possible driver is that there's a strong likelihood money will be coming into China to pay for it." Beside potential World Bank or other international funding, he says, Kyoto nations that want to earn carbon credits might fund carbon reduction in China to help them meet the treaty's requirements. Chinese plants that were already capture ready would be far cheaper to convert to carbon capture and be most likely to attract such funding. Leaked memo? There are also signs the British government likes the idea and could champion it at diplomatic levels, Gibbins says. Support for that notion came on Friday in the form of an apparently leaked diplomatic document that lays out British proposals - including a new 'capture ready' plan - for the G-8 summit in Gleneagles, Scotland, in July. British authorities refused to comment on the document or to confirm or deny its authenticity, according to The Scotsman newspaper's website. A big question is cost. Although making a plant capture ready represents only a small fraction of a power plant's construction budget, the equipment to capture CO2 would almost certainly run into serious money, experts say. Even if a reasonable technology were found, installing it in a capture-ready coal plant would raise construction costs some 50 per cent (75 percent for plants not capture ready), Gibbins estimates. And running such a plant would raise the cost of producing electricity at least 40 per cent due to heat loss involved in the carbon-capture process, he adds. Nevertheless, some in the US think the idea could catch on. Environmental engineers with Alstom Power, a Paris-based supplier of power-plant equipment with operations throughout the US has been studying the capture-ready concept. "It's definitely an idea we think has a lot of merit," says Sean Black, marketing manager for Alstom's environmental control systems division in Knoxville. "I would not say any US plants being designed today are doing it. It's something though that we're going to see in the near future." But Hawkins demurs, saying a far better approach would be for the US to lead by example and implement IGCC widely in the US. Since China pays close attention to power-generation trends, especially in the US, it could follow suit if IGCC were demonstrated in America. Meanwhile, back in Regina, Patrick says he's gotten a warm reception from a power consortium in North Dakota with which he shared the capture-ready idea. "Even though the US government hasn't specifically pushed Kyoto, the writing is on the wall," Patrick says. "At least I sure hope it catches on. Because if it doesn't, the little bit of CO2 we'll capture up here in Saskatchewan will be swept aside by China and India." By Mark Clayton, Staff writer of The Christian Science Monitor Climate change threat to gardens Fields of sunflowers could replace the traditional English landscape. The English country garden is unlikely to survive in the South East beyond the next 100 years, scientists say. Climate change means the rolling lawns and herbaceous borders of Surrey, Kent, Hampshire and Sussex may be replaced by olive groves and grape vines. Global warming is being discussed at a Royal Horticultural Society conference at Guildford's University of Surrey. Experts say summer temperatures in the South East are expected to be up to 3C warmer by 2050 with 35 per cent less rainfall. If the current rate of warming continues, summers could be as much as 6C warmer by the 2080s, the scientists say. "Lawns and herbaceous borders are going to be difficult to maintain, especially in areas of water shortages," said Guy Barter, from the Royal Horticultural Society. "For the average gardener there may be more opportunities but it's going to be very difficult for the National Trust, for example, to maintain the character of its historic gardens." Parts of England could resemble the Mediterranean scenes painted by Vincent Van Gogh, with fields of sunflowers becoming common features along with palms, shrubs and eucalyptus. "It's already happening - you can already see fields of sunflowers," said Professor Jeff Burley, from Oxford University. Levels of sunlight are lower in England than in the Med, but many plant and tree species found in southern France are expected to become more common further north. They include walnut, poplar, sweet chestnut, plums, kiwi fruits and vines, the scientists say. Native woodlands of oak, beech, ash and Scots pine are expected to survive, but beech woodlands are likely to be hit hard in counties such as Kent and Sussex. - BBC News Walk for the Wetlands The Parent-Teacher Association of the Overseas School of Colombo organised a 'Walk for the Wetlands' last month to raise funds for their ongoing conservation projects as well as the tsunami-affected village Kalametiya, which is surrounded by an important wildlife marshland and bird sanctuary. The walk which took place for the 10th consecutive year, has in the past helped and sponsored various projects, while the proceeds from last year's walk have been channelled into producing the 'Student's Wetland Pictorial Resource Book' which has been published by the Field Ornithology Group of Sri Lanka (FOGSL) under the supervision of the President of the FOGSL Professor Sarath Kotagama. This year the OSC's PTA has been extremely successful and had managed to generate nearly US $ 5,000 by way of contributions of corporate sponsors and individuals. President of the PTA Sue Northcott, said there is an ongoing student elective who supervise the conservation and monitoring of the Talangama Tank. "We have used the monies raised from last year's walk to erect information boards and produce this book which will be on sale to the public," she said adding that with the assistance of Professor Kotagama they hope to attract tourists as well as the general public to visit these areas. "The Glossy Ibis is found in the vicinity of the Tank and it is our wish to make people realise that the Wetlands are not Wastelands," said Ms. Northcott. Sunil Sarath honoured
A former Director General of the Rupavahini Corporation, he has introduced a number of new and significant trends to local television and has made communication scholars re-think communication in the light of his practical experiences. Also the Senior Assistant Secretary and one of the Additional Secretaries in the Ministry of Environment and Natural Resources, he has been a member of the delegation that attended the historic Rio Summit on Environment and Development in 1992, organised by the United Nations. He has participated in a number of international conferences on Biodiversity and traditional knowledge ,and some of the ideas such as a model for effective communication and a laboratory for preserving dying languages have been highly appreciated. He edited 'Soba' an outstanding journal in the field of environment and his book Udarata Manike, the journey into the environment, explored the concepts of biodiversity revealing scientific facts in a creative manner. He also co-authored a book on Self, Environment and Communication with the internationally recognised scholar, Professor Wimal Disanayake and contributed further by writing books in Sinhalese on Environment and Communication, sustainable Development - From Rio to Johannesburg, which have been highly recognised by those in the field of environment. To honour perera's contribution towards communication and environment the Association of Environmental Journalists presented him the Green award. The studies he carried out on the program of cleaning rivers in India - (Pavithra Ganga), had been instrumental in initiating the concept of Pavithra Ganga in Sri Lanka. |
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| Produced by Lake House |
Biomass fuels are often touted as a green alternative to oil. Although
the carbon dioxide they produce when burnt is a greenhouse gas that
contributes to global warming, in theory it should be sucked up by the
following year's crop as it grows. 
Sunil Sarath Perera, the two most important Lyricists in Sri Lanka, the
other being Arisen Ahubudu and a noted environmental communi cator, is one
of the recipients of the Sarvodaya National Awards this year. 
