To the rest of the world China looks like an environmental car crash, a superpower superpolluter that along with the USA has become the most obdurate barrier to action on climate change. Every self-respecting green knows that it is building a new coal-fired power station every day, has 16 of the world's 20 most polluted cities and uses an extraordinary 40 per cent of the world's cement to pepper China's landscape with crane-topped half-built skyscrapers. Many believe that China's leaders have trapped themselves on a growth juggernaut, terrified of the unrest that would follow if the growth rate fell much below 9 per cent.

But what if this was soon to change? A discreet meeting of opinion-formers in southern China a few days ago hinted that it might. Qian Zhengying, who opened the proceedings, was an unlikely bearer of the news. This stooped 84-year-old with twinkling eyes was China's first woman engineer, and later became its longest-serving communist minister. She cut her teeth managing the Red Army's water supplies during the civil war and then, as Minister for Power and Water, implemented Mao's commitment to conquer nature, building a vast network of roads and power stations. Her most famous, or notorious, legacy is the Three Gorges Dam, the enormous project to tame the Yangtse that has displaced a million people to provide power for the booming cities of central China.

The dam has become a symbol of industrialising excess. Yet Madam Qian's theme was the need to return to China's great traditions of harmony with nature. China needed to adapt to a new model of development, with more respect for wildlife and landscapes, clean air and water. What's even more surprising is that her words are not heresy but rather the new party line. At the recent 17th party congress, President Hu Jintao spoke of the need for China to be an “ecological civilisation”, with a “circular economy” where waste is reused. Ambitious targets have been set for renewable energy and efficiency, and Beijing already has car regulations more stringent than America.

The occasion for Madam Qian's speech was the second Shantou Dialogue, supported by Li Ka-shing, another extraordinary octogenarian. If Madam Qian was one of the queens of China's planned economy, Li Ka-shing is king of its markets, a master of everything from telecoms to shipping and a retailer with more outlets than Wal-Mart. That he and other business leaders are engaging with environmental issues is another sign of just how quickly the tide is turning.

There are conflicting explanations as to why Chinese ministers and business leaders are suddenly so interested in a low-carbon future. Economics is one factor: official estimates suggest environmental damage is already costing the economy 10 per cent of GDP. More surprisingly, China is now receiving billions from the market for clean development mechanisms, the device created by the Kyoto treaty to trade carbon emissions: a global deal on climate change could multiply that many times over.

Then there's public opinion. Hundreds of millions of Chinese want to own a car. But they also want to escape from the pollution that makes living in Beijing equivalent to smoking 40 cigarettes a day, and they've emboldened

China's embryonic civil society by launching aggressive campaigns to clean up rivers and shut down the worst-offending factories.

Over the past few years George Bush provided cover for China to resist Kyoto or any successors. But with President Bush now the lamest of lame ducks, China knows that it can't afford to be caught on the wrong side of history. Nor do the Chinese like the way they've become the place where the US effectively outsources so much of its pollution. It's an irony for the Americans that on some days a quarter of Los Angeles smog now comes all the way from China — literally — much of it from the factories supplying Wal-Mart.

Nowhere symbolises China's green aspirations better than the new city of Dongtan, which is being built on the mouth of the Yangtse. It has already achieved an iconic status among architects and planners even before a single resident has moved in. Combining state-of-the-art renewable energy with a layout based on public transport and bicycle lanes, and wetlands for migrating birds, it inspired Ken Livingstone to announce that the Thames Gateway should be built on similar principles.

Shanghai's Expo in 2010 — which expects 70 million visitors — will go even farther, showcasing a distinctly Chinese utopian vision of renovated industrial factories, high-density but not high-rise living, reconstituted wetlands, renewable energy and zero waste. It's one of many signs that the next generation of Chinese planners, architects and designers are rejecting Los Angeles as the model for 21st-century urban living.

For many years to come this emerging green China will sit uneasily with the China of concrete towers and multilane motorways. Local officials are still rewarded for how quickly they expand GDP, and Beiing's environmental protection agency has to make do with a mere 250 people — barely a hundredth the numbers at its counterpart in Washington. But the huge machine is turning, and China is already making the other new superpower, India, look complacent on environmental issues.

The rhetorical promise of an ecological civilisation is still far ahead of the reality. But the one advantage of a one-party state, and a still substantially planned economy, is that when it moves, it will move fast, compressing into years an evolution that in the West took decades and centuries.

Geoff Mulgan is director of the Young Foundation and a former Downing Street adviser

Times Recommends

• Farwell to the stiff upper lip
• It’s about who runs the US, not health
• The Iron Lady and her blue felt-tip sympathy