China’s drive to clean up its coal power, one plant at a time
China, the world’s top greenhouse gas emitter, is often chided for its carbon-belching, Dickensian-looking coal plants.
But it is working to clean up its coal power. While this will reduce overall emissions, critics say it chiefly serves to prolong the use of coal power.
Now, a Chinese engineer has re-engineered a Shanghai coal plant to make it one of the world’s most efficient – and a potential model for the country’s coal-burning future.
China has limited oil and gas reserves, so high-efficiency coal is “the only way” for the country to meet its energy needs while also reducing its emissions, says Feng Weizhong, general manager of the state-run Shanghai-Waigaoqiao No. 3 Power Plant.
The plant supplies about 8 per cent of the megacity’s power and is in one of the country’s largest power-generating complexes.
China has shut many coal plants over the last decade, and pledged to increase the share of renewables in its energy mix from 13 per cent in 2010 to 20 per cent by 2030, when it plans to peak its emissions.
The government’s renewable-energy targets will leave “little room” for building new coal plants, and it should do more to incentivise the purchase of untapped wind and solar power, says Ranping Song at the Washington-based World Resources Institute. “The problem now is how to allocate the right to generate electricity,” Ranping says.
Yet coal still accounts for about two-thirds of China’s energy provision, and more than 200 new coal plants have been given the go-ahead. Globally, too, coal demand and production are forecast to grow until at least 2040.
Technology that improves coal-burning efficiency could be useful for retrofitting older power plants, and cut down their emissions.
The mechanical improvements Feng has implemented in Shanghai since 2008 have enabled the plant to mill coal, generate electricity and remove sulphur compounds from its gas stream more efficiently, says Andrew Minchener of the IEA Clean Coal Centre, a London-based non-profit organisation.
Feng’s supporters say that he achieved his efficiency gains in Shanghai by designing site-specific, cost-effective solutions for each component of the plant, and that his attention to detail and insatiable work ethnic are unmatched.
“He worked until midnight — no holidays, no weekends — for 40 years,” says Mao Jianxiong, an energy expert at Beijing’s Tsinghua University who has consulted at the plant.
The plant burns 276 grams of coal per kilowatt-hour, compared with China’s national average of 315 grams per kilowatt-hour, according to Mao.
Feng’s latest project is designing a coal plant that he says will set a national benchmark for fuel efficiency in the sector. Its signature feature, Minchener says, will be a system that more efficiently transfers steam between the boiler and turbine and reduces the need for expensive steel piping.
Mao says the new plant, in the eastern province of Anhui, will burn 251 grams per kilowatt-hour. If all China’s coal-fired plants were that efficient, the country would reduce its annual carbon dioxide emissions by some 7 per cent, he says.
This is similar to the total annual emissions from all aircraft worldwide. Yet many climate scientists and environmental groups are sceptical of efforts to promote “high efficiency” coal.
Building even relatively efficient coal plants will make it harder to meet a global commitment made in Paris last year to keep any global temperature increase under 2 °C, says Bert Metz at the European Climate Foundation. “Phasing out coal use is what is needed,” Metz says.
But an “inconvenient truth” is that carbon-based fuels will continue to power growth across much of Africa and Asia, even as China tightens pollution standards and coal use eventually declines globally, says Minchener.
Feng’s example shows there is scope to improve the technology significantly, Minchener says. “It’s not just limping along to its death.”
By Mike Ives