In the black: China has abundant supplies of coal to fuel future growth. Credit: LI JIANGSONG/IMAGINECHINA

China is booming, and its hunger for energy is insatiable. For its people, the dismal air quality across much of the country is a constant reminder of its reliance on coal and other dirty fuels. When Nature visited Beijing to meet the technocrats responsible for China's energy policy, the city was blanketed in acrid smog. After just a few days of stagnant weather, visibility in some districts had dropped to tens of metres. Flights were delayed and the Beijing Environmental Protection Agency advised people to stay indoors. You could almost taste the sulphur in the air.

Energy and its consequences for health and the environment are high on the Chinese political agenda. But the hard-headed approach of the country's leaders should give us all pause for thought. China's energy policy will continue to be based around coal, they say, so the question of whether this notoriously filthy fuel can ever be made ‘clean’ is central to the country's development — and to the long-term stability of the global climate.

The most immediate problem for China is that its economic growth is already outstripping its energy supplies. In boomtowns from Shenzhen to Chengdu, electricity is now an unstable commodity. Last year, 24 of China's 31 provinces, municipalities and autonomous regions admitted that they lacked sufficient power. In the summer, when drought curtails hydropower and air conditioners surge into life, blackouts have become commonplace.

The nation's coal mines are straining to meet the demand, at a terrible human cost. According to conservative official estimates, more than 6,000 workers were killed in China's mines last year — making them the world's most dangerous — and the death rate was undiminished in the first half of 2005.

Most coal-related fatalities never make the headlines, however. Many Chinese cities fail to meet international — or even their own — standards for air quality, causing hundreds of thousands of premature deaths each year. China's increasing use of coal is also sending CO2 emissions skyrocketing, threatening a global climate disaster. “We understand that coal means not only energy, but also social and environmental impacts in the long term,” says Zhou Dadi, director-general of the Energy Research Institute in Beijing and a leading adviser on energy strategy to China's leaders.

While Dadi and other senior energy planners recognize these problems, their enthusiasm for coal remains strong. The country's leaders are determined that its economy will quadruple in size by 2020, which will require at least a doubling of the energy supply. Coal will bear most of the burden. “We have to increase coal consumption,” says Guo Yuan, an energy systems analyst at Dadi's institute. “It's not a good picture, but we have to do it.”

Electricity generation is by far the biggest consumer of energy, although the demands of the transport sector are growing fast. Between 75% and 80% of China's electricity is generated by burning coal. Another 20% comes from large-scale hydropower projects, with most of the rest coming from nuclear stations. As yet, oil, natural gas and renewables such as wind barely feature in the electricity mix. But by 2020, according to official projections, gas-fired stations could be meeting 15% of China's electricity needs, while nuclear power may have expanded to around 5%. And thanks to a law passed in February this year designed to promote renewable energy, wind and other renewables could account for 10%. However, with power demands poised to double over the same period, it's clear that a massive increase in coal consumption is unavoidable.

Sustaining economic growth is the leadership's priority, say seasoned China watchers, but it wants to achieve this without compromising energy security. China lacks substantial reserves of oil and natural gas, and is determined not to become heavily dependent on imports. But the country has coal in abundance. So it will use the fuel in ever-larger quantities, mainly to avoid a reliance on Russian oil and gas that could eventually bring the two powers to the brink of war.

But can China meet its energy needs without poisoning its environment and filling the lungs of millions of people with particulates and oxides of sulphur and nitrogen? The effects of acid rain are spreading, and there are suggestions that soot is already disrupting the regional climate (see ‘Brown clouds cast a dark shadow’).