BOB HOLMES reports that Daniel Stinger and Farouk Mian have set up a company in Sugar Land, Texas, to market a way of harvesting energy from waste heat using a 鈥渃ascading closed-loop cycle鈥� (快猫短视频, 29 May, p 21). Accompanying the article was a picture of chimneys belching steam and smoke, with the caption: 鈥淭hey might soon be belching electricity.鈥� It stirred me to ask energy minister Stephen Timms if his department was following the Texan technology.
Timms said his officials were in contact with the Environment Agency, the Health and Safety Executive and a manufacturer of large generating sets. From the information gleaned, they suggest things may not be that simple. Although the article implies that the inventors are close to gaining a patent, this does not necessarily mean a practical design can be developed. And the proposed cycle uses flammable propane instead of steam, thus raising safety concerns over any leakage.
Also, the improved thermal efficiency cited in the piece could be matched by conventional technology. For example, waste heat from a gas turbine generator could be used to raise steam in a steam turbine generator, or waste heat from electricity generation could be used in industrial processes or for domestic heating. London鈥檚 Battersea power station was a prime example, the minister said, providing heating and hot water for Dolphin Square in Pimlico.
Advertisement
Timms added that the Texan scientists claim the lower flue temperature would increase the opportunity to capture more mercury and cadmium oxides in waste gases. Current systems comply with the most stringent environmental rules and run at similar flue temperatures, he said. They already capture 90 per cent of the mercury in the flue gas, so it is not immediately obvious where the pollution gains are to be made. But I still think that some research on this technology may be worthwhile.
ANDY COGHLAN recently warned about the spread of infections at the Olympic Games (快猫短视频, 27 March, p 9). I asked the UK sports and tourism minister, Richard Caborn, about steps to prevent the transmission of diseases such as hepatitis B or HIV in contact sports like boxing.
Caborn鈥檚 response was relaxed. He considered the risk of infection during a bout to be minimal. Any infected blood would have to be in prolonged contact with an open wound on an opponent. Current procedures do not include routine blood testing, and anyway, blood tests would not guarantee that a competitor is clear as it can take several months after infection for most diseases to show up in tests.
Stringent procedures are already in place, Caborn said. Referees are instructed to stop matches when bleeding occurs. Failure to stem the flow of blood invariably leads to the end of the bout.
Let鈥檚 keep our fingers crossed that all goes well.
