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50kW system downsized E


NER-G has shrunk its 50kW combined heat and power (CHP) unit by 30 per cent – making it the smallest and lightest unit in its fleet. The new E50 gas fired CHP packs the same power, 90 per cent efficiency and reliability of its predecessor, while matching previous ease of service and maintenance, and quietness of operation.


E50 is designed to meet the demands of sustainable cities, where space is at a premium and noise control is an issue. This is fuelling a growth market for smaller footprint, acoustically insulated packaged CHP systems that can meet BREEAM targets, achieve compliance with sustainable building codes and gain acceptance with planning authorities. Typical applications for the E50 are small


hotels, mixed use developments and small district heating schemes. “In creating the new compact unit,


we were mindful of retaining sufficient space for ease of maintenance, which is a


feature of all our CHP systems”, said Chris Marsland, Technical Director for ENER-G Combined Power Ltd. “Our service team were fully involved in the new product development process and we were able to design in, simulate and test our service and maintenance requirements. In this way we ensured that space was fully optimised and that this important feature wasn’t compromised. “When you consider that an average


CHP system could be serviced five or six times a year, it is critical to consider ease and economy of aftercare, which on a


system of this size could add up to the original capital cost over the 15 year plus lifetime of the asset.” The new technology was


developed at ENER-G’s global R&D and manufacturing centre in Salford, Greater Manchester. As such, its technical, engineering and production teams were able to work alongside its new product development experts and servicing division to design, develop, test, validate and


introduce to market the new E50 system. ENER-G has reduced the environmental


impact of manufacture through using fewer raw materials in production of the E50, while also saving energy and cost in the production process. Due to its smaller size and lower weight, the E50 is easier and less costly to transport, which has major advantages as a product for the export market. ●


For more information, visit www.energ.co.uk/chp


Large hydro-electric dams unviable and seriously damaging to emerging economies


T


he evidence is conclusive: large dams in a vast majority of cases are not economically viable. Instead of obtaining hoped-for riches, emerging economies risk drowning their fragile economies in debt owing to ill-advised construction of large dams. After a decade-long lull, the


construction of large dams has accelerated. Emerging economies of Brazil, China, Ethiopia, Indonesia, and Pakistan among others are rushing to build mega-dams on an unprecedented scale. Yet since 2000, when the World Commission on Dams published its findings, no systematic, global, and independent research has been carried out on the outcomes of large dams. New research from Said Business School, Oxford has now produced an authoritative investigation of whether large dams work or not, based on the most extensive dataset of its kind.


The study is based on data from 245


large dams in 65 different countries. The findings show the construction costs of large dams are on average +90 per cent higher than their budgets at the time of approval, in real terms. This result is before accounting for


negative impacts on human society and environment, and without including the effects of inflation and debt servicing; including these items, costs and cost overruns are much higher. The study also found that the


magnitude of cost overruns has not declined over time. Dam budgets today are as wrong as at any time during the 70 years for which data exist. Costs aside, mega-dams also take an


inordinately long time to build – 8.2 years on average and often more than 10 years. The Oxford study shows that these long time horizons leave dam projects


particularly ineffective in resolving urgent energy crises and especially vulnerable to currency volatility, hyperinflation, political tensions, swings in water availability and electricity prices, a combination of which constitute the typical dam disaster, which is your typical dam project. Professor Bent Flyvbjerg said: “Experts


making forecasts about megaprojects can be usefully grouped into ‘fools’ or “liars’. Fools are the reckless optimists who see the future with rose-tinted glasses. These forecasting fools ignore hard facts and uncertainty, betting the family silver on gambles with very low probability of success. Liars deliberately mislead the public for private gain, fiscal or political, by painting overly-positive prospects of an investment, just to get it going." ●


For more information, visit www.sbs.ox.ac.uk


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