China is booming, and its hunger for energy is insatiable.

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China’sburningambition

The economic miracle that istransforming the world's mostpopulous nation is threatenedby energy shortages and risingpollution. It also risks plungingthe planet’s climate into chaos.Peter Aldhousreports.

hina is booming, and its hunger forenergy is insatiable. For its people,thedismal air quality across much of thecountry is a constant reminder of its

reliance on coal and other dirty fuels. WhenNaturevisited Beijing to meet the technocratsresponsible for China’s energy policy, the city was blanketed in acrid smog. After just afew days of stagnant weather, visibility in somedistricts had dropped to tens of metres. Flightswere delayed and the Beijing EnvironmentalProtection Agency advised people to stayindoors. You could almost taste the sulphur in the air.

Energy and its consequences for health andthe environment are high on the Chinesepolitical agenda. But the hard-headed approachof the country’s leaders should give us all pausefor thought. China’s energy policy will con-tinue to be based around coal, they say, so thequestion of whether this notoriously filthy fuel can ever be made ‘clean’ is central to thecountry’s development — and to the long-term stability of the global climate.

The most immediate problem for China isthat its economic growth is already outstrip-ping its energy supplies. In boomtowns fromShenzhen to Chengdu, electricity is now anunstable commodity. Last year, 24 of China’s31 provinces, municipalities and autonomousregions admitted that they lacked sufficientpower. In the summer, when drought curtails

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hydropower and air conditioners surge intolife, blackouts have become commonplace.The nation’s coal mines are straining to meetthe demand, at a terrible human cost. Accord-ing to conservative official estimates, morethan 6,000 workers were killed in China’smines last year — making them the world’smost dangerous — and the death rate wasundiminished in the first half of 2005.

Most coal-related fatalities never make theheadlines, however. Many Chinese cities fail tomeet international — or even their own —standards for air quality, causing hundreds ofthousands of premature deaths each year.China’s increasing use of coal is also sendingCO2emissions skyrocketing, threatening aglobal climate disaster. “We understand thatcoal means not only energy, but also social andenvironmental impacts in the long term,” saysZhou Dadi, director-general of the EnergyResearch Institute in Beijing and a leadingadviser on energy strategy to China’s leaders.While Dadi and other senior energy plan-ners recognize these problems, their enthusi-asm for coal remains strong. The country’sleaders are determined that its economy willquadruple in size by 2020, which will requireat least a doubling of the energy supply. Coalwill bear most of the burden. “We have toincrease coal consumption,” says Guo Yuan, anenergy systems analyst at Dadi’s institute. “It’snot a good picture, but we have to do it.”

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Global climate change doesn’t yet loomlarge in the thinking of China’s leaders, butinternational experts note with alarm that coalis the worst offender in terms of CO2emissions.“The global problem is climate. But for China,conventional pollution is the main problem,”says Li Zheng, who directs the Tsinghua-BPClean Energy Research and Education Centre,a collaboration between Beijing’s leading sci-entific university and the British energy firm.

Efficiency drive

China’s energy planners have realized thatimproving energy efficiency is the easiest way to promote economic growth whilecontrolling pollution. “China should work first on this,” says Dadi. Predictions thatassume ‘business-as-usual’ suggest that totalenergy demands will rise to the equivalent of 3.5 billion tonnes of coal per year by 2020. Butintroducing a suite of measures to improveefficiency could keep that below 3 billiontonnes, says Dadi. “Technically, it’s do-able.”

This new drive for efficiency stems in part

from a quietly influential initiative run by the San Francisco-based Energy Foundation.Bankrolled for a total of US$40 million since1999 by the Hewlett and Packard foundations,the China Sustainable Energy Program isworking with Chinese energy researchers toSasol about the possibility of building twoimprove efficiency and cut pollution. Prioritieslarge indirect liquefaction plants.

include new efficiency standards for buildings,appliances and vehicles, and promotingCrude substitute

renewable energy sources. Fuqiang Yang, whoNeither process is a model of efficiency, how-heads the Energy Foundation’s Beijing office,ever. Direct liquefaction is about 60% energy-points to recent successes such as the renew-efficient, indirect techniques around 45%. Butable energy law, plus fuel-efficiency standardsChina’s desire to seek alternative liquid fuels isand energy-efficient building codes adoptedso great that Minghua estimates that liquefac-by central and local governments.

tion technologies could be providing it withEnergy efficiency is an admirable goal, butmore than 50 million tonnes of fuel per year byChina’s appetite for growth and the leader-2020. “This is a personal estimate,” he stressesship’s desire to limit imports of foreign oil— but one that will be music to the ears ofmean it won’t be enough. So China is embra-China’s leaders. If Minghua is correct, coalcing technologies that, in the West, remain liquefaction could reduce China’s demand foron the fringes. Du Minghua, director of thecrude by 100 million tonnes per year, or aboutBeijing Research Institute of Coal Chemistry,one-third of its anticipated imports by 2020.sees coal as an energy panacea, able to meetCoal is also central to the thinking ofChina’s demands for electricity, liquid fuelsresearchers at the Tsinghua-BP centre. Zhengand gas. “Coal is the solution for all three,” heis focusing on a strategy called polygenerationexclaims, before launching into a presentationin which a single plant would convert coal intoon his institute’s work on coal gasification

syngas, then use it in gas turbines to generateand liquefaction. electricity and also convert it into liquid fuels2.Finding ways to reduce dependence on oil,Sulphur is removed as an integral part of gasi-critical for the transport sector, is the top pri-fication, cutting pollution. To demonstrate theority for Minghua’s institute. Young coals suchtechnology’s potential, Zheng and his col-as lignite can be converted straight to liquidleagues have conducted a ‘syngas city’ simula-fuels by heating them to 450 ?C with hydrogention for Zaozhuang in the eastern Shandongand a suitable catalyst, Minghua explains.

Province. Like many industrial centres in

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NEWS FEATURE

NATURE|Vol 435|30 June 2005

China’s flood season officiallystarted this month withdestructive floods in manyparts of the country. In the past20 years it has seen increasingsummer floods in the south anddrought in the north. The likelyculprit is air pollution and, asthis escalates with China’s rapidindustrial growth, it could alterweather across the region.The key player in China’sclimate woes is the blanket ofaerosol particles that hoverover Asia. China isn’t alone increating this pollution hazard.India is a major contributor tothe brown clouds of smog —mostly black carbon, organiccarbon and other aerosols suchas sulphates and nitrates —formed by wildfires and by

burning fossil fuels and biofuels. Black carbon, a sooty by-product of coal-burning,absorbs sunlight, resulting in a hotter atmosphere andcooler ground. Sooty particlesalso affect rainfall by seedingsmaller droplets andpreventing the formation oflarger droplets. This aids cloudformation, but reduces theamount of rain produced.To simulate the observedchanges in China’s rainfallpatterns in recent decades, ateam led by Surabi Menon ofthe NASA Goddard Institutefor Space Studies in New Yorkused a global climate modelthat factored in black-carbonemissions4. But althoughclimatologists generally agreethat aerosol pollution hasaltered China’s rainfall, theyremain cautious about itspotential regional impact.“We are dealing with

imperfect measurements andimperfect models,” says GeorgeCarmichael of the University ofIowa. Reliable measurements ofaerosol emissions are lacking,particularly for black carbon.And climate models are riddledwith uncertainties, for examplehow aerosols modify clouds.Even so, studies reveal asimilar picture elsewhere.

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Simulations by VeerabhadranRamanathan from the ScrippsInstitution of Oceanography in La Jolla, California, andcolleagues show that aerosolpollution caused changes overthe north Indian Ocean thatresulted in decreased monsoonrainfall and increased droughtin India5. Similarly, China’spollution could affect

surrounding oceans, alteringmonsoon rainfall across theregion, says Ramanathan.The next step is to reducesome of the uncertainties.Project Atmospheric BrownClouds, run by the UnitedNations Environment

Programme, began monitoringAsia’s smog earlier this year.And improvements in satellitemeasurements of aerosols,together with China’s plans toincrease emission monitoring,will help determine the extentand impact of the country’s airpollution.Carina Dennis

China, Zaozhuang faces a majorproblem: how

to continue growing when the only readilyavailable fuel is high-sulphur coal.

In the ‘syngas city’ model, the Zaozhuangauthorities would provide incentives to pro-mote polygeneration, which not only gener-ates electricity but also produces methanol forvehicle fuel and dimethyl ether for domesticcooking and heating. The simulation suggeststhat polygeneration could meet more than aquarter of Zaozhuang’s electricity needs by2020. It would also achieve drastic cuts insulphur dioxide emissions while reducing theneed to invest in expensive flue-gas desul-phurization technology at conventional powerplants3. Further reductions in air pollutants,such as ozone-forming compounds, wouldcome from the wider use of methanol anddimethyl ether.

Such simulations are the stock-in-trade ofenergy researchers worldwide. But in Chinathere may be a greater chance of their beingimplemented, given the authorities’ power toenforce their will. Preparations for the 2008Beijing Olympics are a case in point. Realizingthat the city’s appalling air quality coulddamage athletes’ health — and present a poorimage of China to the world — the city is nowengaged in a frantic clean-up, closing some200 heavily polluting factories, piping innatural gas, and introducing a clean ‘bus rapidtransit’ system. “The Olympics are a very big

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opportunity,” says Li Hao, who heads Earth-View, a Beijing-based environmental group.Zheng and his colleagues hope that growingofficial concerns about environmental healthwill also boost their proposal to build a poly-generation demonstration plant, costing some5 billion yuan (US$600 million), which wouldgenerate up to 400 megawatts of electricity andproduce as much as 400,000 tonnes of liquidfuel per year. “We got a very good responsefrom the government,” says Zheng.

Greenhouse city

But while polygeneration and other clean-coaltechnologies may help to scrub China’s filthyair, they won’t do much in the short term tolimit the nation’s growing greenhouse-gasemissions. According to Zheng’s simulation,total CO2emissions from power plants wouldbe higher for the syngas city than if Zaozhuangcontinues using conventional technologies3. In the long run, however, polygenerationcould provide a route to a more sustainablefuture, in which hydrogen is extracted fromsyngas and used to power fuel cells, while CO2is captured and sequestered. “But to get there,the investment will be huge,” warns Zheng. Given the costs involved, experts say thatChina’s interest in carbon sequestration willdepend largely on the willingness of Europe,North America and Japan to pay for it. Thosewho work in the energy industry are blunt

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about China’s determination to strike a hardbargain. If the necessary cash isn’t forth-coming, they say, all deals are off.

China’s potential to single-handedly emitenough CO2to negate all other nations’ effortsto control their greenhouse-gas emissions couldplace its leaders in a strong negotiating posi-tion. “If it’s business as usual, then the planet isdead,” says David Moskowitz, director of theRegulatory Assistance Project, based in Gar-diner, Maine, who is advising Chinese officialson reforming the electricity-generation sector. That should provide food for thought forthe leaders of the G8 wealthy nations, whomeet in Scotland in July with global warmingon their agenda. China is a signatory to theKyoto Protocol on climate change, but as adeveloping country it doesn’t yet have an emis-sions reduction target. Whatever strategyworld leaders contrive to save the planet,China will sooner or later have to be broughton board. And that won’t come cheap.■

Peter Aldhous is Nature’s chief news andfeatures editor.

1. Williams, R. H. et al. Energy Sustain. Dev.7,103–129 (2003).2. Zheng, L. et al.Energy Sustain. Dev.7,57–62 (2003).3. Hongtao, Z. et al.Energy Sustain. Dev.7,63–78 (2003).4. Menon, S. et al.Science297,2250–2253 (2002).5. Ramanathan, V. et al. Proc. Natl Acad. Sci. USA102,5326–5333 (2005).

For more on China’s environmental problemssee page 1179.

CHINA PHOTOS/GETTY IMAGES

Brown clouds cast a dark shadow