Developers in China have come up with a paradoxical, environmentally-sound solution to speed up traffic: add more buses.

According to Engadget, the Shenzhen Huashi Future Parking Equipment company is developing a 3D Express Coach that will allow smaller cars to drive underneath it.

Dubbed the 'straddling bus,' the light-rail trains will stand 4-4.5 metres high with two levels. Passengers will board the upper level while smaller vehicles lover than 2 metres can drive right through.

Powered by electricity and solar energy, the bus can reach speeds of up to 60 km/h and carry 1200-1400 passengers at a time without standing in other vehicles' way. Each bus will cost $500 million yuan (approximately $73 million).

Construction of the first 115 miles of track will begin in Beijing's Mentougou district at the end of 2010.