The city and Shell International Gas International Ltd will cooperate to develop clean energy and reduce air pollution by 2010 for the World Expo.

　　Officials yesterday signed a cooperation agreement with Shell International Gas, forming a partnership to get rid of emission-caused air pollution.

　　The agreement, which does not include concrete investments from both parties, cites areas of cooperation such as joint studies on clean alternative fuels and cost-effective ways to reduce emissions, particularly for the city's 40,000-plus cabs and 18,000 buses.

　　Currently, the Shanghai Science and Technology Commission and Shell are collaborating with local Tongji University and Jiao Tong University on trials of clean Gas to Liquids technology.

　　"Shanghai is one of the most progressive cities and is setting an example in clean energy development," Jack Jacometti, Shell's vice president of Global GTL Development, said.

　　GTL is considered as a promising fuel since it is convenient for transport and safe.

　　Normally, natural gas fuel must be compressed into special bottles under very high pressure, causing potential risks during transport.

　　It is also much more environmentally friendly than normal natural gas because it is purified.

　　Air pollution is mainly caused by emissions from the coal-dominated energy structure.

　　Chinese and international energy experts will discuss sustainable development of local public transport through 2030.