Technology Hydroelectricity China's Three Gorges

Technology Hydroelectricity China's Three Gorges DAM Hydroelectricity is a widely used form of energy, accounting for approximately 10% of the energy production in the United States alone and even more worldwide. Thus, hydroelectricity accounts for up to 80% of the renewable energy used in the United States, making it by far the most widely used means of alternative energy production. Its current acceptance and use make it a promising energy source, as it has already become an entrenched idea in the minds of many (Urbauer, 2010).

Hydroelectricity will not drain its resources from being used. Though its location may change, the amount of water stays constant. The water cycle has never been seen to actually stop operating and this is surely an important factor in an energy source's viability for large scale use. Hydroelectricity is considered to be a clean source of electricity for several reasons. Most dams that collect this energy are located in areas that are very low in population. This makes noise pollution a non-issue.

Also, unlike other energy sources, there is no discharge of steam or chemicals, which often affect the environment by causing weather pattern changes. There are also no chemicals at all used in the production of hydroelectricity, making it one of the few truly all natural energy sources (Urbauer, 2010). Hydroelectricity is an economically wise investment most of the time. This is significant because naturally, companies will not chase energy sources they see as being financially demanding.

Such sources are almost impossible to implement on a large scale, where they may be more cost efficient, for specifically this reason. On the other hand, hydroelectricity in right in line with fossil fuels in production cost and may even cost less over the long haul. This makes it a good economic choice, a wonderful selling point. Benefits of hydroelectricity are extensive. They affect everyone from the producers of such energy to those living in the construction area to the end users of the energy.

By generating a positive environment for all parties, hydroelectricity shows promise as a viable source of alternative energy. Its simplicity of implementation, production and usage merge to make it the most used, most recognized and most culturally accepted form of alternative energy, giving it a clear edge over other potentials (Urbauer, 2010). Hydroelectricity is also very clean compared to other forms such as coal and nuclear. Both of these other alternatives emit toxic substances that are neither good for people nor the environment.

China is one of the countries with the most plentiful hydroenergy resources in the world (Jiang, 2005). The Three Gorges Dam Project which is the leading hydropower project in the world is situated in one of the three gorges of the Yangtze River, Xilingxia gorge in Hubei province, China. The gorge controls about 1 million km2 of drainage area and averages a runoff of 451 billion m3 annually. China Three Gorges Corporation (CTGPC) acts as the legal entity for TGP. They are accountable for constructing, operating, and paying for the dam.

Construction on the Three Gorges Dam was finished in 2008. The dam stands 185m high and 2,309m wide making it the world's largest hydro plant in the world (Bristow, 2007). The construction of the dam has not been without controversy though. There are many people who are in favor of the dam because of the many benefits that it has. But on the other had there are many critics that say the benefits do not outweigh the detriments, especially environmental ones, that it brings forth.

A total of 26,700MW power generators were installed with 12 sets on the right bank and 14 sets on the left. They were operational in October 2008 and generated a total of 18,200MW. Since then another six generators have been installed underground. This brings the total of 32 sets of power generators. The last six are thought to become fully operational by 2011. In September 2009, the project proved its power generation benefits by generating 348.4TWh of electricity which is about one third of the project cost.

It is expected to generate 150,000GWh excess power than the initially planned 224,400GWh for a total of 370,000GWh by the end of 2009 (Bristow, 2007) The Three Gorges Dam project involves harnessing the Yangtze River, Asia's longest, to generate prodigious amounts of electricity. Output should be 85 TWh/y, close to one tenth of current Chinese requirements. Another purpose of the dam is to end catastrophic floods downstream, which over the year have claimed many lives.

Improved navigability on the river should also allow much larger ships to sail from Shanghai as far as Chongqing, upstream from the dam and 2,000km from the sea, to aid China's burgeoning domestic and export trade. The dam is positioned 44km from the city of Yichang in the province of Hubei. This point is at the end of a series of steep canyons which will form a 630km reservoir, with an average width of 1.3km. The plant is the center of a much bigger plan for central China's electricity business.

Associated transmission and distribution systems are linked to the three regional grids that make up Three Gorges power. This forms a single system from the coast to the border of Tibet. The grids and their planned shares of offtake are: Central China Power Network (55%); East China Power Network (39%); Sichuan Provincial Grid (6%) (Bristow, 2007) The TGP power distribution and transmission infrastructure was completed in December 2007. Power that comes from the dam is transferred to two cities and nine provinces from three different directions.

A 500kV DC transmission line on East China Grid which has a capacity of 7,200MW, a 500kV DC transmission line to the South China Grid having 3,000MW capacity and a 500kV AC transmission line to the Central China Grid having 12,000MW capacity support the distribution. The East China Grid is connected to three 500kV DC transmission lines which include HVDC Three Gorges-Changzhou with a capacity 3,000MW, HVDC Three Gorges-Shanghai with a capacity 3,000MW and HVDC Gezhouba-Shanghai with a capacity 1,200MW (Three Gorges Dam Hydroelectric Power Plant, China, 2010).

The long-term ecological effect that the dam has had has been described as potentially disastrous. The dam will upset profound silt flows in the river. It is believed that it may cause rapid silt build-up in the reservoir that would create an imbalance upstream, and depriving agricultural land and fish downstream of necessary nutrients. Since these troubles would also hit the plant's turbines and millions of farmers and fishermen, it is necessary to consider the ecology of the entire situation.

Opposition of both environmentalists and politicians to the Three Gorges Dam has been intense. The most controversial issue has been the forced relocation of 1.27 million people in September 2009. China has put in place many detailed plans to improve the lives of those who have been affected, but residents have complained of the resettlement funds and job retraining promises being denied.

The farmland, which will be flooded, is more fertile than higher ground, and some 1,600 factories will be submerged (Bristow, 2007) There are fears that China's Three Gorges Dam is causing serious environmental problems, despite official claims to the contrary. Local farmers, environmental campaigners and even officials themselves have all raised concern in regards to the environmental damage. That damage has included landslides that have brought on 50 meter-high waves on the reservoir behind the dam. Despite these widespread charges, the Chinese central government insists there are no geological irregularities.

Critics of the Three Gorges Dam have long disputed that the plan would lead to environmental harms in the area around the reservoir. Farmers living near the dam's reservoir, which is 660 km (410 miles) long and an average of 1.1 km wide have talked about landslides that are being caused by the huge weight of water behind the dam and fluctuations in the water level.

They talk of frightening tremors since the dam was completed last year that have left cracks in the walls of their homes (Bristow, 2007) China continues to insist that there have been no unforeseen environmental problems in this area. Although they have not discounted the possibility of natural disasters in the future, they have states that there will not be any major damage to life or property.

They have stated that there are less than half of the anticipated levels of silt behind the dam, and eruptions of algae in waterways supplying the reservoir have been controlled. Rare floral and fauna had been protected, and there was only a low risk of reservoir-induced earthquakes (Bristow, 2007) Not content with the Three Gorges Dam, at the 3rd Yangtze Forum in Shanghai it's come out that China plans 20 more dams on the headwater tributaries of the Yangtze River.

The tributaries to be dammed are the Yalong (Nyachu in Tibetan), Dadu (Gyarong Ngulchu), and Wujiang rivers (McDermott, 2005). There's no word on exact capacity of these dams, but Chinese officials have indicated that by 2020 about 50% of the Yangtze's hydropower resources will be tapped, up from about 36% today. By 2030, about 60% of China's longest river's electricity-producing potential will be harnessed. It is believed that by 2030, that more than 30% of the Yangtze's water resources would be used for agriculture or industry.

That's an increase from 17.8% today, in an area likely to see decreasing rainfall in the coming years do to the effects of climate change on precipitation patterns (McDermott, 2005) All of this rightly raises red flags among environmentalists, especially considering the problems with Three Gorges. A recent study by the Chinese Academy of Sciences found that water quality persists to decline in reservoir areas of Three Gorges, which is causing the fish stocks to decline.

Though it's certainly true that hydropower is a better option than profligate burning of coal for China, surely there are more eco-friendly ways to tap into China's world-leading hydropower resources than continued building of large-scale dams (McDermott, 2005) Arguments assembled by the Japanese to support their final decision do provide some answers to the project's critics. After concentrated reviews by the Japanese Ministry of International Trade and Industry, Japan has claimed that this project has presented many benefits.

Japan thinks that this project can achieve its objectives in this area, despite many thoughts that it could actually amplify the risk of floods, either through changes in silt flow or a dam collapse. This issue in particular has drawn a lot of popular sympathy for this project throughout Japan. Another benefit is that of emissions reduction. The plant's output will be equivalent to several large coal-fired plants (Three Gorges Dam Hydroelectric Power Plant, China, 2010).

Japan thinks that current plans are sufficient, although the do agree that the situation would need to be kept under review. China originally maintained that possible problems had been identified and dealt with. But there were further.