Saturday, July 3, 2010
Asia's alarming cities How Asian cities are built will determine the prospects for global carbon emissions. Oh dear
IF YOU are the sort to worry at night about man-induced climate change, then book a stay at any of the new high-rise hotels going up on the edge of China’s big cities—start looking for them around the third ring road. When you stagger red-eyed out of bed to peer into the murky dawn, you will see rank upon serried rank of raw “superblock” developments, a mile apart, marching into the distance. You think of the emissions involved in their carbon-hungry construction, the traffic jams on the arteries tying them into the expanding city, and the new coal-fired power stations being built to light them up. And you wonder how Asia can change its habits—energy consumption grew by 70% in the ten years to 2008—before it is too late for all of us.
Yet the world’s hopes of putting carbon emissions on a manageable path depend upon on how developing Asia urbanises in the coming decades. The scale is staggering. According to the Asian Development Bank, 44m people join city populations each year. Every day sees the construction of 20,000 new dwellings and 250km (160 miles) of new roads.
In theory, urban living can be greener than other ways of life: people need to travel shorter distances, for instance. The practice is not so simple. Most poor people coming to the city aspire to higher standards of living and consumption. Ill-planned public transport reinforces car use. Most striking, putting up and using buildings accounts for a big part of developing Asia’s carbon emissions—perhaps 30% in the case of China, where nearly half the world’s new floor space is built each year. What’s more, the buildings do not age well. Many thrown up in the 1990s are already being pulled down and replaced.
Governments acknowledge the challenge. Green codes in China mandate energy-saving standards for heating, cooling and lighting new buildings. The aim is to cut new buildings’ energy use by 65%. But many new buildings are designed first and greened later—a cheaper but less effective approach.
As for the superblocks that exemplify China’s urbanisation, a dozen new ones are built every day. Yet their conceptual design is flawed, however many low-energy light bulbs they boast. They get built after the city government lays out a system of arterial roads. State utility companies put down power, water and sewage mains. Developers bid for the rights to build blocks with specified numbers of housing units, schools, offices, shops, green space and so on. The developer throws up the block and plugs it into the centralised utilities grid. Presto, people move in.
Yet such hyper-development has unwelcome consequences. Not least, as Harrison Fraker, an architect at the University of California at Berkeley, argues, superblocks in effect become gated communities of privilege.
The social consequences of such isolation (for those inside and out) may take time to make themselves felt: for almost all of China’s history, neighbourhood streets and alleys have enriched urban life. The environmental impact, however, is already apparent. Gated blocks with a single entrance force not just residents to abandon cycling or walking for the motor car whenever they need to go anywhere. Outsiders, too, face a vast, fenced obstacle in the way of where they want to go. Congestion, pollution and traffic accidents rise. Time to build a fourth ring road.
Mr Fraker and his team devised a different approach for Tianjin in north China, by thinking of the development as a whole system in which high-density neighbourhoods would generate nearly all their energy and water needs. First, “greenways” were marked out that gave pedestrians and cyclists a way to get to the nearest mass-transit station without being run down or choked. Meanwhile, good use of sunlight, shading and ventilation would cut heating and cooling loads. Photovoltaic panels and windmills would provide four-fifths of electricity needs. The rest, as well as gas for cooking and hot water, would come from biogas generated from sewage, waste food and plant clippings. Rainwater would flush lavatories. Storm-water run-off would be collected for irrigation, including for allotments and the trees that reduced the “heat-island” effect. Something of China’s traditional urban scale would be echoed by community blocks within the greater scheme, accommodating 100-300 families.
Yet in China the idea appears to have run into the sands because of the radical approach it requires. Developers are ill-versed in thinking about energy, water and sewage as a seamless whole. Utilities think like central planners. Government agencies struggle to operate beyond their traditional remits. What is more, the costs are up to a fifth higher for such developments, though they more than pay for themselves in the long run.
In the short run, dim prospects
Enlightened developers say that their kind should be putting up greener buildings without waiting for Asian governments to set the tone. Christine Loh of Civic Exchange, a Hong Kong think-tank, argues that large amounts of energy can be saved with little effort, dramatically improving efficiency. In the newish hotel by the Kunming ring road in which this column is being written, the bulbs that provide the light are not only electricity-guzzling incandescent ones, but dim and frosted at that.
But Yvo de Boer, the United Nations’s outgoing senior climate-change official, argues that limits to what can be done are set by the perverse economic incentives that apply in most parts of Asia. Developers, a big part of the solution, will struggle to make a profitable fist of turning green when energy and the costs of pollution are grossly mispriced, favouring old-fashioned utilities. Putting an end to these subsidies would do wonders for bringing about a better night’s sleep, and a crisper, more pleasing view in the morning. Banyan for The Economist
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