Green LEDs, artificial leaf, chameleon tiles...

Green lamps: Professor Colin Humphreys of the University of Cambridge is all for the new generation LED lamps. The next generation technology will eventually see today’s compact fluorescents going the same way as Thomas Edison’s incandescent bulbs. The LEDs offer three times the efficiency of compact fluorescent lamps and 12 times that of incandescents. They also switch on instantly, are dimmable, and last for 100,000 hours.

MIT’s ‘chameleon’ tiles
It’s simple physics. Dark surfaces absorb more heat while white ones are more effective in reflecting it. And a team of students from MIT came up with a colour-changing technology to tackle global warming. These MIT graduates reckon they may have worked out a way for buildings to enjoy white surfaces in the summer, before switching to darker surfaces in the winter when buildings typically need to maximise the sun’s heat. They have developed a new tile that changes colour as the temperature changes, producing a white surface when hot, and a black surface when it is cold. Dubbed the Thermeleon, the researchers claim that in their white state, the tiles reflect about 80 per cent of sunlight landing on them, while in their dark state, they reflect around 30 per cent of the sun’s energy.

Humble leaf to power the planet
Researchers at Imperial College London embarked on an ‘artificial leaf’ project to produce power by mimicking photosynthesis. The intricate chemistry involved in photosynthesis is the most effective solar energy conversion process on Earth. These researchers believe that mimicking parts of it could be the ticket to a limitless supply of clean power. The £1m project involves working out exactly how leaves use sunlight to make useful molecules and building artificial systems that can do the same to generate clean fuels such as hydrogen and methanol. These would then be used in fuel cells to make electricity or directly to power super-clean vehicles. According to James Barber, a biologist at Imperial College, London and leader of the artificial leaf project, if artificial photosynthesis systems could use around 10 per cent of the sunlight falling on them, they would only need to cover 0.16 per cent of the Earth’s surface to satisfy a global energy consumption rate of 20 terawatts, the amount it is predicted that the world will need in 2030.

Scarlet Knight for climate change
When a shiny, winged yellow tube touched land in Spain in December, it completed a transatlantic trip that scientists compare to Charles Lindbergh’s famous flight across the same ocean. This battery-powered underwater glider proved itself an effective weapon against climate change, according to scientists. Such gliders can collect data even in the inhospitable North Atlantic and near the melting polar ice caps. They can reach depths of 200 metres (650ft) and withstand seven-metre waves. New battery technologies should allow a glider to “fly” around the world within 10 years. The 60kg (132lb), 2.5-metre-long Scarlet Knight arrived at the exact spot the team was aiming for.

Forests in the desert?
Some talk of hoisting mirrors into space to reflect sunlight, while others want to cloud the high atmosphere with millions of tonnes of shiny sulphur dust. Scientists could have dreamed up the most ambitious geoengineering plan to deal with climate change yet: converting the parched Sahara desert into a lush forest. The scheme was thought up by Leonard Ornstein, a cell biologist at the Mount Sinai School of Medicine in New York, together with Igor Aleinov and David Rind, climate modellers at Nasa. Under the scheme, planted fields of fast growing trees such as eucalyptus would cover the deserts of the Sahara and Australian outback, watered by seawater treated by a string of coastal desalination plants and channelled through a vast irrigation network. The new blanket of tree cover would bring its own weather system and rainfall, while soaking up carbon dioxide from the atmosphere.
(Compiled from The Guardian)