China might overtake the US to become the world's largest emitter of carbon dioxide as early as next year, according to the Energy Foundation, a US non-governmental organisation that works closely with Beijing on energy issues. Yang Fuqiang , vice-president of the foundation, said yesterday an earlier report by the US Energy Information Administration predicting China would become the world's biggest carbon polluter in 2009 should be revised forward. The main reason for the nation's growing carbon emissions is its addiction to coal. At 188 billion tonnes, China has the world's second-largest coal reserves, next to the US, but it is by far the world's largest producer, accounting for 45 per cent of global output. China's consumption of coal was as large as the world's second, third, fourth and fifth biggest consumers combined, Dr Yang said. Although analysts expect diversification of energy sources to see coal's share of China's energy mix drop from 70 per cent to 59 per cent by 2030, electricity demands will still see China burn twice as much coal as it does today. China's impact on global warming is also a huge challenge for the leadership, as the nation's severe water shortages risk being exacerbated by a melting of the Himalayan glaciers. 'Water is actually more serious than the energy issue,' said Dr Yang. 'The Himalayas provide water for a quarter of the Asian people, including Chinese.' China needs cheap energy and coal provides it. During the past 25 years economic growth has helped push annual energy consumption up by an average of 7 per cent a year. As China's cheapest and most secure energy resource, it is inconceivable that coal will not remain the nation's primary electricity-generating source for the foreseeable future. Reliance on coal has a serious impact on public health, with 500,000 Chinese a year dying prematurely because of dirty air.