Green pioneers: Ken Yeang

The Sunday Times
March 29, 2009
Architect’s designs reduce power consumption sharply
Andrew Stone

GREEN buildings are all the rage but they are old hat to architect Ken Yeang. As a PhD student at Cambridge he helped to develop a “self-sufficient” house in the 1970s. Today he is turning such ideas into reality.
His latest project, a £300m extension to Great Ormond Street Hospital in London, will generate 20% more power than it uses, through innovations such as a ventilation flue that does away with the need to heat or cool the building for much of the year.
Construction began last week and, once completed, the building should offset more than 20,000 tonnes of carbon dioxide a year — equivalent to the typical annual carbon footprint of 2,000 people, making it Britain’s greenest hospital building.
Yeang predicts that in the next decade such energy performance will become the norm as large new buildings will generate all their own power.
He credits his study of ecology for his approach to design. “I’m an ecologist first and an architect second,” he said. “Studying ecology changes your perception of life and makes you look again at your place on Earth. It encouraged me to look to ecological systems for inspiration.
“There is no such thing as waste in nature, merely food for other organisms. Waste is very much a human invention, so strive to re-use and recycle everything.”
Yeang and his fellow planners and architects have their work cut out transforming office blocks from energy guzzlers to power misers. The Building Research Establishment recommends that a large building should consume 100 kilowatt hours (kWh) of energy per square metre, said Yeang. The UK average is 250-300kWh.
One of the worst offenders, a bank building in Canary Wharf, consumes 1,400kWh per square metre. “It’s a totally unsustainable building covered in glass, with poor insulation,” he said.
By contrast Yeang’s designs are shaped round the idea of eco-mimesis, designs that are energy efficient because they mimic natural systems.
They work in harmony with their location, maximising energy efficiency through a building’s design, making the most of its aspect, natural light and ventilation. Green technologies such as ground-source heat pumps augment these design features.
The buildings are not just green in terms of energy use. In many cases they are festooned with plants. Yeang’s 24-storey Fusionopolis building in Singapore, for example, includes a 1.4km coil of vegetation.
Planting a grass roof on a tall building and introducing other plants helps to capture rainwater, provide shade and even reintroduces other plant and animal species to a city. Widespread planting of greenery can cool city temperatures in summer by between 1C and 2C.
The technology is constantly improving, said Yeang. “The next generation of solar panels will mimic photosynthesis, promising much greater efficiency, while micro wind turbines should offer a viable way to generate power from the wind,” he said.
However, will developers suffering in the downturn really heed the call to create greener buildings?
Yeang thinks so. At a cost of perhaps 20% of the original build cost they can make existing buildings sustainable, he said. “It’s true that a lot of this depends on the business models of the developers, but sustainable buildings are increasingly attracting subsidies, tax breaks and more generous planning approval.”
- Ken Yeang is director of the UK-based architectural practice Llewelyn Davies Yeang and director of Malaysia’s TR Hamzah Yeang