By Bao Quan

Great pressures are imposed to China's electricity supply, though the broiling summer has not come yet. In the first quarter of this year, there were 24 power grids shutting off the switches to limit the uses of electricity, which increased by 8 than the figure of the same period last year. Electricity and energy saving, though undoubtedly are ways to solve the shortage of power supply, is difficult to take effect in a short term since industrial structure needs to be adjusted correspondingly. China's electricity generation per capita accounts only one-thirteenth of the US, and one-eighth of Japan's. It is imperative for China to make great efforts on the development of energy supply. Then which road should China take, the conventional road of generating through coal and natural gas or the road of generating through renewable energy like wind and solar energy?

He Zuoxiu, the academician of the Institute of Theoretic Physics of Chinese Academy of Sciences, and Dr. Wang Yinan of Institute of Electrical Engineering of Chinese Academy of Sciences point out that efficiency, cleanness and diversification are the trends of energy development in the contemporary world. The European Union plans to increase the proportion of electricity generated by new energy from 13 percent to 22 percent by 2010. The UK expects to increase its proportion of electricity generated by renewable energy to 20 percent by 2020. However, in China's plan of electricity development by 2010, coal power, hydropower, gas power and nuclear power account for 80 percent, 15 percent, 4.8 percent, and 3.9 percent respectively, while renewable energy power like wind power accounts for only 0.4 percent, which deviates greatly from the mainstream of world energy consumption.

Can the utilization of conventional energy solve China's scarcity of energy and electricity? He Zuoxiu and Wang Yinan analyze that if China takes the road of developing coal power, there would be 1.4 to 1.9 billion tons of carbon dioxide emission by 2020, mounting to the world's number one in the light of pollution. China has 823 billion tons of coal reserves, but only 139 billion tons of recoverable reserves. Even counted by the coal consumption volume of last year, the mining could last for only 83 years. If the coal consumption volume is quadrupled, the mining could last scarcely for 20 years. Experts calculate that China's water energy that is available for exploitation is 390 million kilowatts. Even the complete exploitation and utilization can only double China's installed volume and annual electricity generation. It is not realistic to depend on hydropower to tackle the problem of power shortage. Therefore, He Zuoxiu and Wang Yinan indicate that combining the factors of resources, technologies, economy, and environment protection, wind power generation is the important strategic choice to settle China¡¯s scarcity of electricity and energy.

According to statistics, electricity generated by renewable energy like wind power is developing at the highest speed in world¡¯s energy and electricity market in recent 10 years. The increase rate of solar power generation is as high as 30.9 percent, followed by 30.7 percent of wind power generation. The price of electricity generated by solar power is higher than that generated by wind power and fuel coal, because of the high cost of solar cell technology, which restricts the development of solar power. Wind Force 12: A Blueprint to Achieve 12% of the World's Electricity from Wind Power by 2020 is signed recently by European Wind Energy Association and Greenpeace. It states that by 2020, the installed volume of global wind power generation will reach 1.2 billion kilowatts, 38 times that of 2002; wind power generation will account for 12 percent of the world¡¯s total, and becomes the most important alternative energy in the future.

The maturity of wind power technology contributes to the rapid growth of wind power generation. At present, the production of wind turbine generating sets with individual capacities of 500, 600, and 750 kilowatts has reached the level of commercial production. This kind of wind turbine generating sets have become the main model of the world¡¯s wind power generation. The sets with larger and better capacities have also been developed and operated experimentally. For example, some wind farms newly established in Denmark have individual capacities of over 2 megawatts. The design and manufacture of vanes of new wind turbine generating sets use new technologies and new materials, as well as new electronic and calculating technologies, which has effectively improved and advanced the overall designing capability and level of wind power generation.

Because of the application of new technologies, the price of wind power that draws most of concerns is decreasing rapidly, and approaching the cost of coal-generated electricity gradually. For example, in the US, the cost of wind turbine generating set has dropped from US$ 1,333 in 1990 to US$ 790 in 2000. The cost of electricity generation has also decreased from 8 US cents per kilowatt-hour to 4 US cents, and is expected to reach about 3 US cents per kilowatt-hour in 2005 and almost equal the cost level of conventional electricity generation equipment. The life span of wind power generation equipment is 20 to 25 years. The operational expenses of this equipment is equal to only 4 percent of the cost of the equipment set. Experts anticipate that the cost would reduce by 15 percent as the capacity of world¡¯s wind power generation doubles.

Then where do wind power resources come from? As per the present technological level, wind power generation would be economic as long as the wind is 10 meters above the land and at the speed of over 5 meters per minute. It is estimated that the world¡¯s wind power resources show tremendous potentials, with 53 trillion kilowatts per year. China also possesses large-scale wind power resources available for exploitation and utilization. It is studied that available wind power resources on land are 253 million kilowatts. In addition with offshore wind power resources, there are more than 1 billion kilowatts wind power resources, exceeding hydro-energy resources by over a double.

Dr. Wang Yinan once inspected the Huitengle wind farm in Inner Mongolia. The wind farm has 72 equipment sets, most of which are imported. However, its tariff on wind power connected with grid, including taxes, has decreased to about RMB 0.5 per kilowatt-hour. The cost can be recovered in less than 7 years. In case the equipment is China-made, the price will be more competitive.

The academician He Zuoxiu and Dr. Wang Yinan believe that wind power generation is of incredible significance in the respect of mitigating electricity shortage. Wind power generation can be launched quickly and its construction cycle can be counted by week or month. In addition, wind power generation is able to effectively contain greenhouse effect and sand storms. An equipment set of one megawatt contributes to the reduction of emission of 2000 tons carbon dioxide, 10 tons sulfur dioxide, and 6 tons nitrogen dioxide. In addition, foreign experts hold the opinion that the wind farm, since it absorbs wind power, can protect valuable surface soil and effectively suppress the sand storm. Wind power is characterized by dispersion, which is more suitable for western areas and vast rural areas. It is more simple and applicable than the model with large equipment sets, large power grids and high voltage.