China's green building boom

With China’s economy on the up and up, developers are willing to back futuristic eco-projects that strive to reduce their energy footprint. Alex Frew McMillan reports.

Hampered by a smog of bad press over pollution issues, China may not have the best record when it comes to the environment. But the People’s Republic is, somewhat surprisingly, one of the frontrunners in the quest for sustainable real-estate development. Certain projects are even being built with an eye to a building generating its own energy instead of just absorbing it.

Take Dongtan Eco-City, Shanghai. The aim is to create a whole city that will be as energy efficient as possible. The Shanghai Industrial Investment Co. is the developer, and engineering firm Arup, which says the project will be the world’s first city built specifically around sustainability, came up with the master design. The project will eventually cover 84 square kilometres. But the first phase will be a more manageable 6.3 square kilometres, designed to house a population of 80,000.

Arup intends to deliver a project that is quantifiably more energy efficient. Based on comparisons with existing city construction standards and planning, it calculates that the Dongtan Eco-City design reduces energy use by 64 percent, resulting in a reduction of 350,000 tonnes of carbon dioxide per year.

It also looks at social, economic and environmental considerations. For instance, the plan maximises open space per capita and also strives to allow people to live as close to work as possible.

“These factors are driving the design, not the other way around,” says Stanley Yip, the Hong Kong-based Director of Arup’s Planning and Development. “It is very difficult to compare two plans and say, ‘Which one is more sustainable?’ The design process has to change. It is not just a creative process. It is also a technical one, and it must be measurable.”

Arup has a second project in Beijing where the goal is to reduce energy consumption over a 400-hectare residential area by 20 percent. “The government is setting very specific performance standards and growing the amount of policies on that front, so the design needs very strong technical backup to measure energy reduction, renewable energy and so on,” says Yip.

In Asia, China is taking the lead among countries that have buildings designed in conformity with the LEED standard. While the Prosper Centre, right at the heart of Beijing’s Central Business District, was the first commercial project in the country to achieve LEED, other LEED-certified facilities now include Dow Chemical’s R&D centre and GE’s corporate campus (both in Shanghai) and Otis Elevator’s office in Tianjin.

The Pearl River Tower in Guangzhou, meanwhile, is an example of a building intended to be a zero net energy consumer. Designed by architectural firm Skidmore, Owings & Merrill (SOM) as the headquarters of the Guangzhou Tobacco Company (part of CNTC, the China National Tobacco Corporation), this 71-storey office tower will be completed in October 2009. It will have very low carbon emissions and in fact be a net producer of energy.

The London Borough of Merton was the first municipality to set specific standards for renewable energy. It created the “Merton rule”, that any commercial development would be required to have at least 10 percent on-site renewable energy.

Now the United Kingdom government has a plan to require all new houses to be carbon-neutral by 2016. China is also starting to look at such requirements - its current five-year plan looks to reduce emissions by 10 percent, for instance.

That kind of planning requires a new financing model for projects. The government, the developer, the builder and the end user must all buy into the concept of sustainable development.

“It is no longer just the developer or builder who shoulders the cost,” Yip says. “You need to get the government and the end user to help finance the development.”

But the commitment seems to be there in China, where the government is keen to support renewable energy. For instance, Yip says the total surface area of all the solar panels in China amounts to 76 percent of the world’s total and is growing at 20 percent to 30 percent per year.

Francis Cooke, the Design Director of the Shanghai office of Skidmore, Owings and Merrill, is impressed by the open attitude to environmentally friendly construction projects that he has seen in China.

“The commitment to renewable energy is definitely much greater in China than it is in the United States,” he says.

His company has been designing the Pearl River Tower in Guangzhou, which is incorporating many groundbreaking approaches to energy efficiency. The building should be the first zero-energy skyscraper in China when complete.

Cooke credits the developer with backing such a futuristic design. The government in Guangzhou is also commited to the project.

“You’ve got to give credit to the client, who said let’s go for it,” Cooke says. “There is an upfront cost. We went back to the government and said, ‘We’ve got a very forward-looking design,’ and the government put up money for it.”

Construction started in 2006 and the building should be complete in 2009. It will have 71 floors and 2.3 million square feet of office space. Much of the space will be taken up by the Guangdong arm of the China National Tobacco Corp.

To make the building as energy efficient as possible, it has been necessary to reconsider almost every aspect of the building’s construction and structure.

“There is no one magic bullet,” Cooke explains. “There is no one strategy that will take care of everything.”

The designers say the building can reduce its overall energy use over a conventional building by around 58 percent.

The outside of the building features photovoltaic cells that absorb solar energy. That is then used to heat the building’s hot water supply and to create electricity.

The photovoltaic cells are particularly useful on the sides of the building that face south and north, since these get the most sun. Since the sun also heats the building, the design includes a double wall designed to trap the heat, feeding the heat up the building into a turbine. It also channels cool air down into the building, cutting down on air conditioning.

“I was shocked that even in winter, these buildings need cooling,” Cooke says. The floor-fed ventilation system aims to suck up the heat generated by the people working in the building, while the ceiling has a radiant cooling system with chilled water flowing through beams.

Cooke points out that green technology does not necessarily have to be more expensive. For instance, the heating, ventilation and cooling system designed for the Pearl River Tower is narrower and more efficient than a conventional HVAC system. That allows the building to incorporate an extra five floors, resulting in 100,000 square feet of extra space that would otherwise have been wasted.

Perhaps the most innovative feature of the design incorporates wind power. The force of the wind is a particular problem for tall buildings, with wind sheer making the building sway and shake.

The Pearl River Tower has pairs of large apertures on each of its mechanical floors, allowing air to flow through the building. This reduces the building’s shaking, and wind turbines turn the wind whistling through the building into electricity.

Cooke points out that forward-thinking building design also tries to use natural gas and methane as a power source where possible, since these are renewable resources and more environmentally friendly than coal-powered electricity. Attempts are being made to harvest the natural gases produced by trash dumps, for instance.

Methane or natural gas can then be used to power micro-turbines, virtually mini-jet engines that can sit in the base of the building and be used to generate its electricity.

The designers of the Pearl River Tower hope that it will eventually even generate more power than it uses. Because smart buildings can generate some of their own power, Cooke said the United States is starting to employ a system of ‘net metering’, where buildings pay for the electricity they use off the conventional grid system but can actually reduce their bill if they produce energy themselves.

“You pay for the energy off the meter, but if you are generating energy, you can run the meter backwards,” Cooke says, adding that a net metering system was starting to be implemented in Guangzhou. “During the day an office building uses a lot of energy. But at night, it can feed energy back into the system.”

Cooke said Pearl River Tower should pay back the extra cost of its design in the form of energy savings within four to eight years. Yip said Dongtan Eco-City should have a payback period of eight years for energy savings and five years for water and waste management.

Energy-efficient construction may have been brought to the forefront by Al Gore’s movie, An Inconvenient Truth, but market watchers agree the trend is here to stay.

Peter Young, the Head of Technical Services and Sustainability at Hongkong Land, notes that green issues are becoming more and more important for landlords and developers. Hongkong Land estimates that a good eco-profile can result in a 6 percent boost in occupancy and a 3 percent to 5 percent premium in rentals.

“It would be very imprudent if you are building a Grade-A office building not to incorporate green elements,” Young said.

Given time, futurists are hoping energy efficiency will no longer be considered a groundbreaking feature in the real-estate industry. The technology will eventually graduate from the ‘world of tomorrow’ to the present day.

“Eventually it is going to become standard, just like elevators are necessary for a 20-storey building,” Cooke says. “It won’t be viewed as a novelty and will eventually become normal practice.”

Return to the green living homepage for more articles on eco-friendly construction, renovation, landscaping and decorating. Search too for the latest on green celebrities, fashion and travel destinations.