Although the curtain has fallen on the Expo, for Sun Jiwei, chief of the Jiading district in Shanghai, it actually marks a new beginning for China's urban development with its legacies on sustainability.

The district, 30 km from downtown Shanghai, is ready to pilot China's low-carbon development in its urbanization drive by using green technologies and concepts showcased at the Expo, he said.

Thanks to the successful demonstration of more than 1,000 electric and hydrogen fuel-cell buses at the Expo, the streets of Shanghai are expected to see 20,000 new-energy vehicles by 2020 as the government steps up its support of the industry.

About 70 percent of that target will be met in Jiading, which has strong research and development in the sector, as well as manufacturing capacity, said Sun.

He said the district government will offer preferential policies, infrastructure and service support for the development of the industry, and that the government will be a major purchaser of new-energy cars to accelerate their use on the roads.

Jiading New Town, a suburban city currently under construction, will be a test zone for emerging low-carbon technologies which are likely to become norms for future cities, said the chief.

One technology likely to be replicated in the new town is the Air Tree, which was exhibited at the Madrid Case Pavilion at the Expo.

The tree, a steel decagon structure designed for better ventilation, can use natural air and wind to cool internal temperature by as much as 8 C.

Sun said the planning of the new town tries to retain as many old buildings as possible by adapting them to new functions, minimizing the environmental impact of large-scale demolition. Most of the old construction materials will be put into use again, he said.

Sun, who has a PhD in architecture, said China has a long way to go to make its construction sector green. Many of the so-called green buildings in China focus only on energy saving and heat preservation, while the concept of green entails a whole system of practices from the use of environmentally friendly construction materials to the low-carbon lifestyles of inhabitants.

"China has only very elementary standards for green buildings. The government should come up with compulsory and stricter regulations in the sector to help it really go green," he said.

"Meanwhile, people's habits and lifestyles will be the essence of a low-carbon city. We should educate people more on that."