An architect’s sustainable dreams

London’s carbon-neutral BedZED project made Bill Dunster’s name. Now, the UK’s premier eco-architect is fine-tuning his microgeneration schemes in China – and Europe, too, will benefit. Maryann Bird reports.

Helios, to the ancient Greeks, was the personification of the sun. According to mythology, he guided his horse-drawn chariot across the sky each day. In one tale associated with Helios, his son Phaeton once prevailed upon his father to let him make the daily crossing. But the boy lost control of the chariot, veering too high and freezing the earth, then too low, drying and scorching the planet. The madness ended only when an angry Zeus – the supreme god, the god of the sky – hurled a lightning bolt that sent Phaeton plummeting from the heavens. Order was restored to the earth.

In the 21st century, radical changes in climate are again wreaking havoc for we mortals. Ice caps and glaciers are melting, deserts are expanding and drought is increasingly common. The world is getting warmer, a phenomenon largely attributed to rising levels of greenhouse gases (primarily carbon dioxide) in the atmosphere. This time, humans alone control the reins; they alone must find solutions to address the challenges ahead.

Out along Helios Road, in London’s outer-southwest borough of Sutton, sits one example of the way forward: BedZED, Britain’s first and largest carbon-neutral eco-community. Completed in 2002, BedZED (the Beddington Zero Energy Development) has numerous lessons in sustainable living — about holding the environmental line without reducing the quality of life — to impart. They are lessons learned from what BedZED did right, and what went wrong.

“We don’t claim it’s a perfect project,” says architect Bill Dunster. “There’s no doubt it can be done better.” Dunster is now applying the lessons of BedZED — built for the U.K.’s Peabody Trust housing association and the BioRegional Development Group – both at home and in China, where he has two projects under way. “China is the frontline against climate change,” he says. “We see it as the most important thing to get right.”

BedZED, built on a brownfield (wasteland) site 20 minutes by train from central London, today features 99 homes – a mixture of flats and townhouses — and 1,405 square meters of workspace occupied by over 200 residents and 60 workers. The development is highly energy-efficient and built with sustainable construction materials: natural, recycled or reclaimed, and sourced within a 35-mile radius of the site wherever possible. Close to public transportation, BedZED also hosts London’s oldest car-sharing club as well as solar-driven power points for recharging electric vehicles.

Its buildings are topped with colourful, wind-driven ventilation cowls that swivel in the breeze, ushering in fresh air while funnelling out the stale. Birds perch atop them, occasionally descending to find insects in the rooftop greenery. Solar photovoltaic panels absorb the sun’s rays (even on cloudy days), contributing to the overall power mix.

BedZED is topped with colourful, wind-driven ventilation cowls

All BedZED’s flats face south to maximize the sun’s heat and light, and are heavily insulated to retain warmth in winter and coolness in summer. Residents have small conservatories and private gardens, and their homes’ interiors are fitted with low-energy lighting and appliances, along with water-saving devices in the kitchens and bathrooms. BedZED statistics show that water-efficient appliances have cut the development’s mains water use (the public supply) to 91 liters per person per day, compared with a UK average of 150 liters.

While BedZED was designed so that all its energy is generated renewably from wind, sun and biomass, there have been persistent problems with the biomass aspect. The development’s combined heat and power (CHP) plant has proved to be technologically troublesome. Fed by wood chips from tree-trimming waste, the CHP plant was meant to produce electricity for BedZED while harnessing the heat by-product – which is lost in conventional electricity generation – for such uses as providing hot water through super-insulated pipes. (Wood is a carbon-neutral fuel, because the carbon dioxide released through burning it is equal to that absorbed by the tree as it grew.) The persistent technical problems, however, have meant greater reliance on domestic hot-water tanks, which double as radiators.

As a result, BedZED’s renewable energy supply has fluctuated between meeting 80% of the site’s needs in 2003 and 11% more recently. Like other homes in London, BedZED then relies on the national power grid. The same holds true for water: in periods of scant rainfall – like the past summer – there was little for BedZED to store and reuse for toilet flushing, so the site had to fall back on additional mains water, the public supply.

Another key technology, the “living machine”, has also been out of action. The ambitious sewage water treatment plant involved employing reed beds to filter domestic waste water for reuse in toilet flushing and gardening. It has proved to be uneconomical, with high operating and maintenance costs. In better days, though, the treatment plant and the rainwater harvesting saved another 15 liters of mains water per person per day.

“The combined heat and power plant has been very problematic,” Dunster acknowledges. “And that’s a big lesson learned. The higher the technology, the quicker it breaks and the quicker it becomes useless. The higher the maintenance, the more uneconomic it is to run. So, luckily — seven years later — there is a replacement coming for that, which will be reliable and need less maintenance. Technology does move on.”

“The ‘living machine’ has worked but not been maintained,” he adds, “and has been difficult to be adopted by the water authorities, who have been reluctant to engage in micro-treatment of water on site — as the electric utilities have been reluctant to engage in electric and heat generation on site.”

“But the [energy] load-reduction exercises have basically worked,” says Dunster. “The buildings don’t need much heat. The workspaces are now very popular. In fact there’s a shortage of space.” While BedZED actively encourages telecommuting and such other “green lifestyle” behaviour as recycling, car-pooling and using a local organic-food delivery service, residents are not compelled to join in.


Some representatives of BioRegional — WWF’s partner in promoting “one planet living”, or the sustainable and globally equitable use of the planet’s resources — are disappointed that residents’ take-up of green opportunities is not greater. But Dunster says he is not worried. “You can set up these options, but you can’t make people use them. All of these things can suddenly ramp up overnight, and you haven’t got to change anything here at all. It’s all there waiting for you.”

He adds: “I think our job — as people who are paid to think about these problems and to almost plot a power-down route as the world copes with peak oil and peak nuclear — is coming up with a way of ameliorating the ‘cold turkey’ that you get after addiction to fossil fuel, and getting down to a society, or planning a society, that could work if people want it to.

“So you can then argue: ‘Is it the wrong scale?’ Have we got all these technologies on too small a scale? Should it be a huge development — 2,000 homes? That’s one argument. The other argument, which I personally favour, is that it should go down a scale. We are now embracing certain domestic and building-scale microgeneration solutions.”

Microgeneration is, in Dunster’s thinking, revolutionary – and where increasingly urban China enters the picture. “The key is reducing the cost — and that can only be achieved by collaborating with people like the Chinese and helping them get the economies of scale in their industries so that the costs come down, so that we can adopt these concepts in Europe as well. … So it’s a double carbon-save, a double carbon-win.”

“We’re trying very hard to get our supply chain, all our components made, in China now,” he says. “The Chinese can’t afford to import any [energy microgeneration] products at all. … The Chinese market is very cost-conscious. All these ideas rely on keeping things simple and reducing the costs. So we’ve got to be, all the time, designing with economies of manufacturing in mind.”

“In our company now, we’re no longer [only] architects,” he adds. “We design our own low-energy components, and we try to help all the way through the process, rather than just saying, ‘I’ve designed this — go and make it.’ ” Dunster’s office, which now conducts about a third of its work in China, is currently working on solar-powered air conditioning and dehumidification specifically for the Chinese market. 

“But the barriers in both Europe and China are always the same,” he finds. “You can’t afford to do something different because nobody else is doing it. So, all the time, you’re building prototypes which are too expensive. It’s a vicious circle.” 

To tackle the problem, Dunster says, he found “very good suppliers” in China for the two projects he’s currently planning: a BedZED-sized low-rise development on the outskirts of Beijing and a high-density project in Changsha, in south-central China’s subtropical Hunan province. He has one building under way in the Changsha project, in the suburban district of Kaifu, encompassing show flats, retail outlets, a hotel, a swimming pool and other sports facilities.

It is, Dunster says, “a prototype for a new kind of urban block, replacing tower blocks and Wal-Marts, which is what they do now” in China. Covered with undulating parkland, the site is “all mixed up – work, retail and community spaces mixed with houses.” He adds: “What’s important is that air blows through the east- and west-facing [rather than south-facing] homes. They have a cooling problem, not a heating one.” Because the Changsha site calls for ventilation, fresh air and dehumidification, passive, horizontal wind cowls are incorporated in the design.

Dunster’s other Chinese project is a Zero (fossil) Energy Farm (ZEF), about 30 miles from Beijing, a new community beyond the Chinese capital’s last ring road and surrounded by fields. In the early planning stages, it is designed for microgeneration, with solar electricity, a wind turbine and a reed bed for water-filtering on top of a community building. The development is to include varying sizes of homes, a fishing lake, a farm shop supported by local agriculture, a café, work space and underground parking in the high-density part of the site. A show house is nearly complete. “We think this is significantly more advanced than the stuff that’s being built in the UK,” he says. 

“All of the microgeneration technology is allowing decentralised energy production and reimpowering ordinary people,” Dunster points out. “We think this is the future, because there is a direct relationship between having your own set of solar panels, your own micro-wind turbine, and actually being aware of your carbon footprint and energy use. The feedback is very direct.” 

With large-scale public projects, such as nuclear power plants (which he opposes) or wind farms, “it’s too remote. We believe it’s ultimately self-defeating. There is a place for what we call ‘green grid’. But there is — in no way, shape or form — enough renewable generating opportunity to ever meet current energy demand from renewables – ever, ever, ever. You have to get a 70% to 80% load-reduction first — through energy efficiency and microgeneration — and then the green grid can work.”

Through his network in China, Dunster will be bringing back to the UK solar thermal collector panels and combination solar thermal and wood pellet boilers, which he says will be on the British market for about £5,000. “That gives you zero-carbon heating.” He aims, too, to battle the notion that green construction is prohibitively expensive (and that shipping equipment from China is any more carbon-intensive than, say, moving parts by large truck from Spain). With the economies of scale he is pursuing, and a “minimal” mark-up for administration and shipping, Dunster says, “ordinary people will be able to get most of this microgeneration technology”.

There is a large market for eco-friendly dwellings, he says, adding that some 2,000 people are waiting for one of his homes, but only about 20 are built each year. “Nuclear doesn’t work. We’re running out of fossil fuel,” Dunster argues. “Who has a better idea? We have the answers, but near 0% government support.” 

“Old excuses won’t work,” says Dunster. “It’s down to a professional, consistent, determined approach. We’d be sorted now if planning had been done.” In Britain, he adds, meeting a goal of 80% carbon-reduction by 2050 is possible, with no extractive technology (such as oil drilling) or nuclear power, so long as there is a concentration each year on increased energy efficiency. That means, annually, 60% more solar hot water, 50% more solar electricity, 25% more micro-wind turbine power and 100% more biomass heating.

“When we built BedZED,” Dunster reflects, “we didn’t see climate change coming so soon. If we had, we would have passive cooling, more shading, solar thermal collectors, micro-wind turbines. No CHP, but a wood-chip boiler instead. And we’d try and get people, the residents, to be fully engaged in the design process. That would sort out the hostility between the uber-greens and the people who just want to get on with it.”

Like Dunster, China, too, wants – and needs — to just get on with it.

Maryann Bird is a London-based freelance journalist with a special interest in environmental and human-rights issues. A writer and editor, she was previously a staff member at Time magazine (Europe), The Independent, the International Herald Tribune and The New York Times.