Is a city without traffic jams, road accidents, exhaust fumes and gasoline really possible?

To commuters in Shanghai and dozens of other major cities around the world, it might seem like a fantasy, but two major exhibitions at the World Expo 2010 depict such a world only be 20 years in the future.

The SAIC-GM Pavilion depicts a future in which urban commuters drive zero-emissions cars powered by renewable energy, such as solar, wind and hydrogen power.

"We are trying to travel through the time and lead people to urban transport in 2030," says Jin Qi, curator of the SAIC-GM Pavilion, which has the theme "Drive to 2030."

The pavilion was jointly built by General Motors Company (GM) and Shanghai Automotive Industry Cooperation Group (SAIC), one of China' s biggest vehicle manufacturers.

"Future transportation should have no greenhouse gas emissions, no traffic accidents, no oil consumption and no traffic jams," says Jin.

"In 20 years, driving should be fashionable and fun with new energy vehicles in a multi-layer transportation system, including subways, roads and airlines."

The "fun" part, according to GM, comes from "autonomous driving," which means vehicles will be able to communicate with each other and with the roads that carry them.

The multi-layer transport theme takes off in the China Aviation Pavilion, where visitors can see 3D displays of future urban transport, with images of future aircraft and vehicles traveling on water, below ground and in the air. The whole city becomes a multi-layered transportation space.

Trackless vehicles will take visitors on an experience of flight in the future with a display called "Aviation Dream Comes True," which combines three-dimensional video and special effects, including sound, light, water and fog.

Modern urban transport faces severe challenges, says Jin Qi. Globally, a traffic accident occurs every 30 seconds, while urban commuters lose significant amounts of income and waste a lot of fuel in traffic jams.