Meanwhile, the elderly and disabled still face major hurdles in urban travel and the world's oil is expected to be exhaused in the next 40 years.

"Future transportation development should be focusing on solving the problems," Jin says.

A concept vehicle called the YeZ (from the Chinese word for "leaf"), a green buggy-type car with a large leaf-shaped roof, is being displayed with four other concept vehicles, including three electric networked vehicles (EN-V), in the SAIC-GM Pavilion.

The roof of the YeZ absorbs solar energy and transforms it into electricity while spinning rotors on the four wheels generate power from the wind, says Ma Zhengkun, YeZ designer and director of design at SAIC.

The body of the YeZ can also absorb carbon dioxide and water, like a leaf, and transform them to electricity.

"Not only will the YeZ not pollute the air, it will actually help clean the air, which redefines the relationship between vehicle and nature," says Ma.

All five vehicles featured autonomous driving, which would release travelers from the steering wheel, according to Ma.

Autonomous driving technology combined with traffic network control systems are expected to sharply reduce road accidents.

Meanwhile, experts still hope public transport systems will be more popular in the future.

"Future transportation may explore space in the air. At the same time, people need to find more efficient substitutes for oil, as well as improving public transport to encourage people to take trains or buses," says Zhang Xin, director of Beijing Jiaotong University's power and engineering department.

The International Association of Public Transportation (UITP), which is also exhibiting at the Expo, is promoting the economic and environmental benefits of public transport and better urban planning.

"Public transport will play a more important role in the future," says Kay Yang, project specialist of the UITP's Asia-Pacific office.

The UITP has issued recommendations to its 300 members worldwide, including the Beijing Municipal government, and the public transport companies in Beijing and Shanghai, to double the percentage of people who travel on public transport by 2025, Yang says.

The UITP says this can be achieved by secure funding and investment, changes in services and business cultures, integrated transport polices and carrot-and-stick tactics.

"Public transport will always be an efficient way to protect the enviroment and reduce the burden of urban transportation, no matter how multilayer transport networks or new energy vehicles develop."

(Xinhua News Agency April 26, 2010)