Yahoo News 10 Sep 09;
CHICAGO (AFP) – China could meet all of its future electricity needs with wind power if the government continues to subsidize the development of wind farms with price guarantees, a study published Thursday has found.
Already the world's largest emitter of carbon dioxide, China's electricity needs are expected to double in the next two decades and it is currently adding several new coal-fired power plants to its grid every week.
"The real question for the globe is: What alternatives does China have?" said lead author Michael McElroy of Harvard's School of Engineering and Applied Sciences.
McElroy's team used meteorological and geographical data to calculate China's total wind capacity and then estimated how much power could be delivered profitably at different floor prices.
They found that wind energy providers could profitably supply all of China's projected electricity demand by 2030 if they receive at least 0.516 yuan (7.6 US cents) per kilowatt hour for the first 10 years.
That's in line with the price guarantees China has awarded in recent concessions to wind farm operators which ranged from 0.382 to 0.551 yuan per kilowatt hour.
"This suggests that it would be possible to eliminate much if not all of the carbon dioxide expected to be emitted by the power sector over the foreseeable future," the study published in the journal Science concluded.
A contract price as low as 0.4 yuan per year would be sufficient to displace 23 percent of energy generated by coal, the study found.
"This would require a major investment of resources and could be accomplished only on the basis of a carefully designed long-range plan for the Chinese power sector," the authors wrote.
"Benefits in terms of improvements in Chinese air quality would be substantial, however, and there could be important benefits also for the Chinese economy."
By contrast, meeting future needs with coal could increase carbon emissions by 3.5 gigatons a year from the current annual level of 6.6 gigatons.
Health problems caused by air pollution are currently estimated to cost 0.7 to 4.3 percent of China's GDP, the authors note.
And while the authors estimate it would cost about six trillion yuan (900 billion dollars) to introduce 640 gigawatts of wind power over the next 20 years, they note that is just a fraction of China's current annual GDP of about 26 trillion yuan and major investments in generating capacity must be made regardless.
China's future energy needs could also be met without radically altering its landscape or displacing farmers, the authors found.
A network of wind turbines operating at as little as 20 percent of their capacity would be able to produce as much as 24.7 petawatt hours of electricity annually, which is seven times the country's current consumption.
"Wind farms would only need to take up land areas of 0.5 million square kilometers, or regions about three quarters of the size of Texas," said co-author Xi Lu, a graduate student in McElroy's group at Harvard.
"The physical footprints of wind turbines would be even smaller, allowing the areas to remain agricultural."
Wind energy currently accounts for 0.4 percent of China's total electricity supply, but China is the world's fastest growing market for wind power and ranks number four in the world for installed capacity.
Current government policy calls for capacity to grow from the current level of 12.2 gigawatts to 100 gigawatts by 2020.
The Answer to China's Future Energy Demands May Be Blowing in the Wind
Wind power is growing by leaps and bounds in China and might one day supply a significant portion of the country's electricity needs--but not until it surmounts a host of challenges
Sarah Wang, Scientific American 10 Sep 09;
After just four years of rapid development, China has the world's fourth largest wind power capacity: more than 12 gigawatts. However, the power of the breeze has become available so fast that the nation is struggling to make use of it.
For instance, the Jiuquan wind power base in Gansu Province—better known as "Three Gorges on Land"—is expected to supply 10 gigawatts of electricity when it reaches peak capacity in 2020. The wind farm, under construction in the Gansu Corridor—a narrow natural passage cutting through the Gobi Desert, Qilian Mountains and the Alashan Plateau—is just one of seven such giant complexes approved by the Chinese government.
In conjunction with other wind farms in China, Jiuquan might be able to meet the country's entire electricity demand by 2030, according to a September 11 study in Science. In fact, a $900-billion network of wind power plants built over the next 20 years and covering 500,000 square kilometers could provide nearly 25 petawatt-hours of electricity, seven times greater than the nation's current consumption, the researchers estimate.
China seems determined to arrive at that future, installing 6.25 gigawatts of turbines in 2008 alone and aiming for 100 gigawatts by 2020. "The wind has just taken off here," says Li Junfeng, deputy director of the Energy Research Institute under the National Development and Reform Commission (NDRC), the government ministry charged with economic development. But "new wind projects only accounted for 7 percent of the entire new power-producing capacity added in China last year, compared to 42 percent in the U.S. and 43 percent in Europe." And wind power currently accounts for just 0.4 percent of China's generating capacity as a whole.
The larger, looming challenges currently facing China's wind farms include serious problems in connecting grids with larger networks, low-quality turbines, and wind farms that have been poorly sited. And another consequence of all these factors is that the current boom has yet to bring a profit to many wind farms.
Profit problems
Chinese wind power generation capacity, it is estimated, could reach 20 gigawatts by the end of 2009, according to the Chinese Wind Energy Association (CWEA), up from 12.15 gigawatts at the end of 2008. By comparison, globally, there were 120.6 gigawatts of operating wind power capacity at the end of 2008; Europe accounted for 66 gigawatts and the U.S. accounted for 25 gigawatts of the total, according to the Global Wind Energy Council (GWEC) in Brussels.
Chinese wind farms, however, "in general have difficulties in operation or even lose money," according to a government State Electricity Regulatory Commission report, which came out in July. For starters, so far, there is less wind power actually being generated than previously estimated by CWEA. The report notes that China's wind power generation capacity in 2008 should actually have been calculated as 8.94 instead of 12.15 gigawatts because some turbines were installed but not used, thanks to government mandates that set as a target the quantity of turbines rather than the amount of electricity they can generate.
In any case, China's wind farms currently struggle to connect with grids, creating power delivery problems. For instance, many of the farms are located in less developed northern and western provinces, such as Gansu, where patchy grids cannot manage the fluctuations in electricity production inherent in wind power.
Also, the power produced would have to be transmitted thousands of miles to high-energy demand areas on the densely populated coast in order to make a profit, a feat that is impossible today because of the lack of long-distance transmission technology or the funding to install it. One solution would be international assistance. "The U.S. also has to transmit wind power over long distances. The two countries can have technological cooperation," says engineer He Dexin, president of CWEA, who has been promoting wind energy since 1980.
The U.S. has infrastructure issues, too, such as aging and regionally constrained electrical grids, and Europe sometimes sees delays in connecting turbines to its grid. But getting intermittent wind turbines to work properly with the existing grid is "indeed a problem in China, much more so than in Europe and the U.S.," says Angelika Pullen, GWEC's communications director.
In the longer run, grid reconciliation is "not a real obstacle," NDRC's Li says. Half of China's grids were built in the past four years (70 percent in this century). They can be upgraded with better technologies. "We will improve our grids and build new ones to catch up with the wind power boom. We can work it out," he says.
Turbine troubles
One advantage in China—the cost of producing a turbine there is 70 percent of the international cost, Li says. China-made wind power devices accounted for 75 percent of the technology installed at Chinese wind farms in 2008, up from 57 percent in 2007, according to CWEA, thanks in part to central and local government mandates that require an ever-growing percentage of equipment at a wind farm in China be made domestically. For example, the NDRC stipulates in a 2005 regulation that wind farms cannot be built when the percentage is lower than 70.
But the quality of homegrown wind turbines is a serious problem. Many of the roughly 70 turbine manufacturing companies in China were set up in just the past four years. "Turbine producers need to test-use their products, especially their first ones, but some give no time to the step," He says. Some turbines cannot be used when they are installed, and some develop broken blades or cracked axes just a few weeks after they begin to operate.
And some wind farms have been built where there is not enough wind to ensure consistent generation of power, He adds. "The wind power sector is growing too fast. It needs to be stable for a period so that there can be a sustainable development in the long term," he says.
Despite these issues, government continues to chase the wind, setting the price for renewable power as high as 0.61 yuan per kilowatt-hour in July, about 10 percent higher than current prices for electricity from such installations. Wind farms also sell carbon credits at between 6 and 12 U.S. cents per kilowatt-hour. "They are major players in China's carbon trading," Li says.
And the links between alternative energy, economic development and climate change pertain no less in China than elsewhere in the world. Harvesting wind power may be key to reining in China's emissions of greenhouse gases. "Our study shows that it is financially feasible to have wind as an important alternative to coal as a source of energy for electricity generation in China," says Wang Yuxuan, associate professor of environmental science and engineering at Tsinghua University in Beijing, who co-authored the September 11 Science paper. "It is possible for China to use wind power on a large scale and to eliminate much, if not all of the CO2 expected to be emitted by the power sector over the foreseeable future."
Powerful Ideas: Reducing China's Carbon Emissions a Breeze
Charles Q. Choi, livescience.com Yahoo News 11 Sep 09;
China is now the world's largest producer of carbon dioxide, the most important global warming pollutant. However, new findings suggest wind farms could potentially eliminate much if not all of China's carbon dioxide emissions from the power sector for the foreseeable future.
Demand for electricity in China is increasing at a rate of about 10 percent per year. At the same time, coal accounts for roughly 80 percent of total electricity production. This suggests that China's emissions of carbon dioxide could grow accordingly.
For example, the equivalent of 800 gigawatts of coal-fired power plants are needed to meet the rising Chinese demand for electricity anticipated by 2030. This could add as much as 3.5 billion tons of carbon dioxide emissions per year, compared to current annual Chinese emissions of 6.6 billion tons.
Wind is currently only a minor contributor to China's energy needs, with an installed capacity of 12.2 gigawatts at the end of 2008, or just 0.4 percent of its total electricity supply. However, China is now the world's fastest growing market for wind power, with an annual growth rate of more than 50 percent over the past decade.
"The world is struggling with the question of how do you make the switch from carbon-rich fuels to something carbon-free," said researcher Michael McElroy at Harvard University. "The real question for the globe is - what alternatives does China have?"
To see how much energy wind farms could generate for China, scientists at Harvard University and Tsinghua University analyzed wind data from a state-of-the-art NASA global weather and climate model that incorporated measurements worldwide from surface observations, aircraft, balloons, ships, buoys and satellites. They also looked at the Chinese government's energy bidding practices and financial restrictions to figure out regional costs for delivering wind power.
They found that onshore wind farms could profitably generate enough power to accommodate all of China's electricity demand projected for 2030, about twice its current consumption. The researchers assumed the wind energy would be produced from a set of land-based 1.5-megawatt turbines operating over non-forested, ice-free, rural areas with a slope no more than 20 percent. They also accounted for the fact that turbines often operate at as little as a fifth of their rated capacity in China, due to a combination of factors, such as lower quality of Chinese turbines, limitations of the power grid, and less-than-optimal placement of turbines to take advantage of wind resources.
"Wind farms would only need to take up land areas of 0.5 million square kilometers, or regions about three quarters of the size of Texas," said researcher Xi Lu at Harvard University. "The physical footprints of wind turbines would be even smaller, allowing the areas to remain agricultural."
A switch to wind power could prove invaluable to curbing any impact China would have on global climate, the researchers noted - as much as 1.1 billion tons of carbon dioxide could be saved per year if just 30 percent of the additional electricity China required by 2030 were produced from wind rather than coal.
"China is bringing on several coal fire power plants a week," McElroy said. "By publicizing the opportunity for a different way to go we will hope to have a positive influence."
This switch to wind power would demand a major financial investment up-front and require careful long-range planning on China's part. Still, the benefits for the Chinese economy could be substantial, as the value of damages linked with air pollution is estimated at up to $167.7 billion, or 4.3 percent of the nation's roughly $3.9 trillion gross domestic product.
"China has become a leader in the wind power industry, not just because of issues surrounding environmental protection and climate change mitigation, but potentially because of all the potential jobs it could create, the potential economic benefits it might have if China becomes a leader," said renewable energy industry researcher Joanna Lewis at Georgetown University, who did not participate in this study. "There are security benefits as well that they're thinking seriously and strategically about, from relying on renewable sources of energy and not requiring imports."
"This study really illustrates how wind can be an important part of China's climate change mitigation strategies, how it can play a much larger role in China than today," Lewis added. "But realistically, it can't be the only part, because it won't be feasible to replace all of coal power with wind power in the time scale we would need to address climate change."
In the coming months, the scientists plan to conduct a more intensive wind study in China, taking advantage of 25-year data with significantly more detailed information for north Asian regions to investigate the geographical year-to-year variations of wind. The model used for analyzing China could also be applied for assessing wind potential anywhere in the world, onshore and offshore, and could be extended to solar generated electricity, they noted.
They are also investigating how wind can be integrated into the power grid in Texas, for example, Lu told LiveScience.
Lewis added that more research needed to be done "on why wind farms have been producing less power than they should in China, and how the power structure currently supporting wind power can be modified to make sure it gets developed properly. If you're building all these farms, you want to get as much from them as you can."
McElroy, Lu and their colleagues detailed their findings in the Sept. 11 issue of the journal Science.
