Charging stations for electric vehicles are to be placed throughout Shanghai to make it easier to run more green buses on its streets.

The city will have 400 more roadside charging points and seven to 10 large stations by the end of this year, said Zhou Minhao, deputy director of its economics and information committee, on Friday.

The stations will be essential to meet the needs of the "dozens" of electric buses that will be running on a daily basis, he said.

The move will follow the construction of China's first electric vehicle charging station last October in Xuhui district as part of a program to promote renewable energy.

Only a handful of electric buses are on the road in the city today, apart from those serving visitors to the 2010 Expo. About 1,000 vehicles using clean energy have been put into use to help achieve "zero emissions" at the event, said Zhou.

"The electric buses running at the Expo site have been functioning well. That has paved the way for broader application outside the site and after the Expo," he said.

The new charging stations, like the existing one, would be just for electric buses, as there is still some time to go before private electric vehicles will be available to the public sector.

Technical problems in the development of electric vehicles, as well as a lack of sufficient infrastructure facilities, pose major obstacles to a wider application of the technology, said Zhou.

Shanghai is one of the first Chinese cities to promote the use of electric vehicles under a national campaign launched in 2008. The central government's "Ten Cities, One Thousand Vehicles" plan aims to demonstrate the operation of 1,000 vehicles in at least 10 cities each year to encourage people to buy them.

Organizers hope that the 2010 Expo sets the model for a greener future. As such, it has the largest application of solar power generation in the history of the World Expo, aside from the large-scale use of electric vehicles.

The gross capacity of solar power produced in the Expo Garden could hit about 4.7 billion kilowatts, leading to a reduction of 4,000 tons of carbon dioxide.