Super capacitor buses, green vehicles with zero emission which were invented and produced in the city, are expected to be used on bus routes in Hong Kong, local bus operator said yesterday.

The buses are undergoing a series of tests in Kowloon, Hong Kong, officials said.

He Fang, a spokesman with the operator Shanghai Bashi Public Transportation Group, said yesterday that the technology "had received wide praise in earlier tests in the middle of August."

He said the ongoing tests would last for several months and will take place under all possible weather conditions.

Based on the current test results, it's very likely the buses, now servicing across the World Expo site and some other routes in Shanghai, will become part of the transit system in Hong Kong, said He.

The 61 super capacitor buses serving inside the Expo site have handled nearly 20 million passengers and run over 640,000 kilometers.

That's when Hong Kong traffic officials, who visited the Expo, showed interest in the technology and decided to run a pilot operation in the densely populated city.

Shanghai started research on the super capacitor bus in 2002. A breakthrough was made in 2006 when 10 such buses went on commercial operation on one downtown route, officials said.