Hybrid, electric and fuel-cell vehicles could ease the burden, but they will not solve the problem because at the moment more than 70% of China's electricity is powered by coal,the dirtiest of all fossil fuels. Even if there is a large-scale take-up of the new technologies,which could cut emissions by 19%.McKinsey estimates that the combined emissions from road transport would still increase more than fourfold within the next two decades.Faced by this nightmare, the Chinese authorities recently announced plans for 50, 000-yuan rebates for electric and hybrid cars,encouraged city taxi fleets to buy vehicles with the new technology, and prompted state and regional grids to set up charging stations.BYD is likely to be a major beneficiary. The initials stand for Build Your Dreams, which prompted snickers when the company debuted in US car shows last year,as did the soaring ambitions of the founder Wang Chuanfu, who has stated that BYD will be the biggest carmaker in China by 2015 and the biggest in the world by 2025.