Beijing air pollution
The Chinese capital has for many years suffered from serious air pollution. Primary sources of pollutants include exhaust emission from Beijing's more than five million motor vehicles, coal burning in neighbouring regions, dust storms from the north and local construction dust. A particularly severe smog engulfed the city for weeks in early 2013, elevating public awareness to unprecedented levels and prompting the government to roll out emergency measures.
China to build new hi-tech power network to help fight pollution
China will build the world's largest high-power electricity transmission network as part of the country's efforts to battle smog and pollution.
The State Grid Corporation of China - the world's largest state-owned utilities company - said on its website that the central government would soon approve plans for the construction of 12 power lines connecting the energy-rich interior with heavily industrialised coastal areas. The initial investment is estimated to be at least 210 billion yuan (HK$264 billion).
The 12 projects include eight ultra-high-voltage (UHV) lines, which offer distinct advantages over conventional power lines by transmitting electricity over significantly longer distances with far greater efficiency. Energy losses from UHV power lines are five to six times lower than the conventional ones, studies show.
Despite some concerns about the project - especially the vulnerability of such a broad network to system-wide failures - the emerging technology is being hailed as an ultimately far cleaner, more efficient way to deliver electricity across the country.
State Grid claims UHV power lines can reduce the density of PM2.5 smog particles, which are considered most dangerous to human health, by 4-5 per cent in central and eastern regions and cut coal consumption by 200 million tonnes a year.
Video: A view of Beijing's smog from atop the Forbidden City
Once completed, the grid will allow China to relocate many power plants from populated areas near Beijing, Shanghai and Guangzhou to remote inland areas, as UHV lines can transmit power over distances two to three times greater than conventional power lines.
In theory, this will greatly help China fight smog and pollution, both rapidly growing sources of public discontent. More than 75 per cent of China's coal reserves are in the northwestern region, while 80 per cent of hydropower is concentrated in the southwest. Yet 70 per cent of electricity is consumed by the populous eastern provinces.
While UHV technology is not new, China is putting it to use most aggressively. Similar grids - but on much smaller scales - are being tried in Russia and Japan.
The central government decided to approve the hugely expensive projects after they were endorsed in the National Action Plan for Air Pollution Prevention and Control released last year amid a series of smog crises, according to the State Grid report.
The UHV lines will stretch from Inner Mongolia, Shanxi, Shaanxi and Yunnan to Beijing, Tianjin, Hebei and the Yangtze and Pearl River deltas. When completed, the UHV grid will allow many coal-fired power plants, regarded as a major contributor to China's air pollution, to be retired.
The State Grid report cited the company's president, Liu Zhenya, as saying that UHV technology was the "ultimate cure" for smog.
Not everyone is convinced the benefits outweigh potential risks. One concern is that the new power network will be more vulnerable to blackouts as local problems could quickly develop into a system-wide crisis.
However, Professor Chen Shuiming, a researcher at Tsinghua University's department of electrical engineering who was involved in drawing up proposals for the new UHV lines, was confident Chinese engineers had solved "nearly all difficult issues" of the technology.
But whether the new lines should be built was a political decision, he said.
"State Grid will enjoy the biggest benefits. They are using the public's fear of smog to push through these projects. It is a smart [political card], but I have my reservations as to what extent it can effectively reduce air pollution," Chen said.