A worker of gas station refuels "B5" biodiesel for a farm vehicle in Chengmai County, south China's Hainan Province, Nov. 22, 2010. Biodiesel has been on a trial sale in 12 gas stations in Hainan recently. [Xinhua]

A worker of gas station refuels "B5" biodiesel for a vehicle in Chengmai County, south China's Hainan Province, Nov. 22, 2010. Biodiesel has been on a trial sale in 12 gas stations in Hainan recently. [Xinhua]