SHANGHAI, April 30 (Xinhua) -- China tried to hold a low-carbon opening ceremony for the Shanghai World Expo Friday evening, a fair featuring ideas for sustainable urban life.

From energy-efficient stereo system and LED screens to clean and smoke-free fireworks, green ideas were in full swing at the ceremony.

Program menus, brochures, gift handbags and props for the ceremony were made of recyclable paper, and used milk boxes had been turned into 2,000 VIP seats.

The Expo site boasts a 4.7-megawatt solar power system, China's largest, with solar panels installed on Expo buildings, according to Expo organizers.

Most of the materials used to make the pavilions will be recycled, and zero-emission vehicles are used for transport within the Expo grounds, said the organizers.

In addition, a wide range of "urban best practices" will be on show in many local and corporate pavilions, showing sustainable urban technologies.