Building a zero-carbon world
2010-01-15 from:guardian author:Terry Slavin
As world-famous architectural practices go, Bill Dunster's premises are like no other. To find him you have to travel to a remote commuter station in an insalubrious outpost of suburban Surrey. Then it's a 10-minute hike past a builder's yard, down-at-heel convenience shops and a Tudor-style estate before you spot the jaunty, brightly coloured ventilation cowls and sleek wooden exteriors of BedZed, the zero-carbon eco-village that has made Dunster's name as Britain's foremost green architect.
BedZed was built not for trendy loft-living urbanites but for housing association the Peabody Trust and, four years on, Dunster remains true to its spirit: that environmental design should be aimed at the suburban masses rather than the right-on elite.
These days, however, the masses are more likely to be found in Beijing than in Bolton. Like Arup, the UK engineering consultancy that is planning an eco-city three-quarters the size of Manhattan outside Shanghai, Dunster sees fast-expanding China as the new frontier for environment-conscious urban design. State planners have suddenly 'got' the environment in a big way, and this year China announced a major investment programme in renewable technologies. By the end of 2010, all Chinese buildings will need to reduce energy use by a headspinning 50 per cent.
A development of 140 Dunster-designed homes based on BedZed's model of high-density, low-carbon suburban living will be built on the outskirts of Beijing this year. And earlier this year Dunster unveiled proposals for a suburban extension of Changsha, the capital city of Hunan province. As a trial project, Dunster has already designed the concept building for the community of 4,500, which incorporates show flats, leisure facilities, restaurants and a small hotel under an undulating grass roof.
Energy used to heat and cool buildings in China produces vast amounts of CO2 emissions, Dunster says, and Changsha, in landlocked central China, is a particularly harsh environment. In the summer, daytime temperatures are in the high 30s and staggering humidity levels make air- conditioning 'almost a human right'.
For the Chinese market, Dunster has adapted his trademark ventilation system, the wind cowls that draw fresh air into his super-insulated buildings, by injecting a saline solution to take the humidity out of the air, and small amounts of solar-powered electricity to cool it. He is in the process of commercialising the technology with a large Chinese company and wants to show the Chinese that clever design to harness the power of wind and sun, combined with small amounts of renewable energy, can reduce CO2 emissions to nearly zero.
'The biggest strategy is to reduce the electricity they need,' he says. 'We can give them high-performance architecture that designs out the need to invest in coal-fired power stations to sort out their cooling loads.'