Misplaced Pages

#524475

76-569: The dam is also part of the “world’s largest clean energy corridor”, where it joins other mega hydropower projects like the Three Gorges Dam , Wudongde Dam , Xiluodu Dam , and Xiangjiaba Dam , all located on the same river system, to produce and transmit renewable energy from the resource-rich western region to the cities in the east. In addition to power generation, the hydropower project also provides flood control , improved navigation, and sand blocking. In June 1959, an on-site survey

152-492: A light bulb with a power rating of 100 W is turned on for one hour, the energy used is 100 watt hours (W·h), 0.1 kilowatt hour, or 360  kJ . This same amount of energy would light a 40-watt bulb for 2.5 hours, or a 50-watt bulb for 2 hours. Power stations are rated using units of power, typically megawatts or gigawatts (for example, the Three Gorges Dam in China is rated at approximately 22 gigawatts). This reflects

228-634: A capacity of 700 MW, and two plant power generators, each with capacity of 50 MW, for a total of 22,500 MW. Among the 32 main generators, 14 are installed on the dam's north side, 12 on the south side, and the remaining six in the underground power plant in the mountain south of the dam. Annual electricity generation in 2018 was 101.6 TWh, which is 20 times more than the Hoover Dam . The main generators each weigh approximately 6,000 tonnes and are designed to produce more than 700 MW of power each. The designed hydraulic head of

304-492: A constant opposing force of one newton , the rate at which work is done is one watt. 1   W = 1   J / s = 1   N ⋅ m / s = 1   k g ⋅ m 2 ⋅ s − 3 . {\displaystyle \mathrm {1~W=1~J{/}s=1~N{\cdot }m{/}s=1~kg{\cdot }m^{2}{\cdot }s^{-3}} .} In terms of electromagnetism , one watt

380-448: A dam proposal for a "Yangtze River Project". Some 54 Chinese engineers went to the US for training. The original plans called for the dam to employ a unique method for moving ships: the ships would enter locks at the dam's lower and upper ends and then cranes would move them from each lock to the next. Groups of craft would be lifted together for efficiency. It is not known whether this solution

456-495: A flat rate of ¥250 per MWh (US$ 35.7) until July 2, 2008. Since then, the price has varied by province, from ¥228.7 to ¥401.8 per MWh. Higher-paying customers, such as Shanghai , receive priority. Nine provinces and two cities consume power from the dam. Power distribution and transmission infrastructure cost about 34.387 billion yuan. Construction was completed in December 2007, one year ahead of schedule. Power

532-427: A flood in the same area caused billions of dollars worth of damage, when 2,039 km (787 sq mi) of farmland were flooded. The flood affected more than 2.3 million people, killing 1,526. In early August 2009, the largest flood in five years passed through the dam site. During this flood, the dam limited the water flow to less than 40,000 m /s (1.4 million cu ft/s) per second, raising

608-428: A generating capacity of 1.0 GW , taking the generating capacity to 16,000 MW . In terms of generating capacity, it is the second largest hydroelectric power plant in the world, after the Three Gorges Dam . It is estimated to generate 62.44 billion kilowatt-hour (kWh) annually and will save about 90.45 million tons of coal per year and consequently reduce annual carbon emissions by 248.4 million tonnes. Surveying of

684-431: A kind of elevator for vessels. The ship lift can lift ships of up to 3,000 tons. The vertical distance traveled is 113 m (371 ft), and the size of the ship lift's basin is 120 m × 18 m × 3.5 m (394 ft × 59 ft × 11 ft). The ship lift takes 30 to 40 minutes to transit, as opposed to the three to four hours for stepping through the locks. One complicating factor

760-557: A move toward limiting greenhouse gas emissions . However, the dam has led to some ecological changes, including an increased risk of landslides, which have made it controversial domestically and abroad. Sun Yat-sen envisioned a large dam across the Yangtze River in The International Development of China (1919). He wrote that a dam capable of generating 30 million horsepower (22 GW)

836-477: A total of 198 million tonnes of freight passed through the locks. The freight capacity of the river increased six times and the cost of shipping was reduced by 25%. Originally, the total capacity of the ship locks was expected to reach 100 million tonnes per year. In 2022, their cargo turnover reached 159.65 million tons, with an annual increase of 6% over the past few years. These locks are staircase locks , whereby inner lock gate pairs serve as both

SECTION 10

#1732766144525

912-541: A turbine, which generates 648 MW e (i.e. electricity). Other SI prefixes are sometimes used, for example gigawatt electrical (GW e ). The International Bureau of Weights and Measures , which maintains the SI-standard, states that further information about a quantity should not be attached to the unit symbol but instead to the quantity symbol (e.g., P th = 270 W rather than P = 270 W th ) and so these unit symbols are non-SI. In compliance with SI,

988-495: A unit of time, namely 1 J/s. In this new definition, 1 absolute watt = 1.00019 international watts. Texts written before 1948 are likely to be using the international watt, which implies caution when comparing numerical values from this period with the post-1948 watt. In 1960, the 11th General Conference on Weights and Measures adopted the absolute watt into the International System of Units (SI) as

1064-470: Is 181 m (594 ft) high above the rock basis. When the water level is at its maximum of 175 m (574 ft) above sea level, 110 m (361 ft) higher than the river level downstream, the dam reservoir is on average about 660 km (410 mi) in length and 1.12 km (3,675 ft) in width. It contains 39.3 km (31,900,000  acre⋅ft ) of water and has a total surface area of 1,045 km (403 sq mi). On completion,

1140-657: Is a hydroelectric gravity dam that spans the Yangtze River near Sandouping in Yiling District , Yichang , Hubei province, central China, downstream of the Three Gorges . The world's largest power station in terms of installed capacity (22,500  MW ), the Three Gorges Dam generates 95±20  TWh of electricity per year on average, depending on the amount of precipitation in

1216-544: Is distributed over multiple 500 kV transmission lines. Three direct current (DC) lines to the East China Grid carry 7,200 MW: Three Gorges – Shanghai (3,000 MW), HVDC Three Gorges – Changzhou (3,000 MW), and HVDC Gezhouba – Shanghai (1,200 MW). The alternating current (AC) lines to the Central China Grid have a total capacity of 12,000 MW. The DC transmission line HVDC Three Gorges – Guangdong to

1292-448: Is enough flow, power output is limited by plant generating capacity. The maximum power-output curves were calculated based on the average flow rate at the dam site, assuming the water level is 175 m and the plant gross efficiency is 90.15%. The actual power output in 2008 was obtained based on the monthly electricity sent to the grid. The Three Gorges Dam reached its design-maximum reservoir water level of 175 m (574 ft) for

1368-537: Is home to 6,388 plant species, which belong to 238 families and 1,508 genera. Of these species, 57 are endangered. These rare species are also used as ingredients in traditional Chinese medicines. The proportion of forested area in the region surrounding the Three Gorges Dam dropped from 20% in 1950 to less than 10% as of 2002, adversely affecting all plant species there. The region also provides habitats to hundreds of freshwater and terrestrial animal species. Freshwater fish are especially affected by dams due to changes in

1444-572: Is made up of five stages, with transit time at around four hours. Maximum vessel size is 10,000 tons. The locks are 280 m long, 35 m wide, and 5 m deep (918 × 114 × 16.4 ft). That is 30 m (98 ft) longer than those on the St Lawrence Seaway , but half as deep. Before the dam was constructed, the maximum freight capacity at the Three Gorges site was 18.0 million tonnes per year. From 2004 to 2007,

1520-733: Is named after the Scottish inventor James Watt . The unit name was proposed by C. William Siemens in August 1882 in his President's Address to the Fifty-Second Congress of the British Association for the Advancement of Science . Noting that units in the practical system of units were named after leading physicists, Siemens proposed that watt might be an appropriate name for a unit of power. Siemens defined

1596-469: Is that the water level can vary dramatically. The ship lift must work even if water levels vary by 12 m (39 ft) on the lower side, and 30 m (98 ft) on the upper side. The ship lift's design uses a helical gear system, to climb or descend a toothed rack. Megawatt The watt (symbol: W ) is the unit of power or radiant flux in the International System of Units (SI), equal to 1 joule per second or 1 kg⋅m ⋅s . It

SECTION 20

#1732766144525

1672-523: Is the rate at which electrical work is performed when a current of one ampere (A) flows across an electrical potential difference of one volt (V), meaning the watt is equivalent to the volt-ampere (the latter unit, however, is used for a different quantity from the real power of an electrical circuit). 1   W = 1   V ⋅ A . {\displaystyle \mathrm {1~W=1~V{\cdot }A} .} Two additional unit conversions for watt can be found using

1748-530: Is used to quantify the rate of energy transfer . The watt is named in honor of James Watt (1736–1819), an 18th-century Scottish inventor , mechanical engineer , and chemist who improved the Newcomen engine with his own steam engine in 1776. Watt's invention was fundamental for the Industrial Revolution . When an object's velocity is held constant at one meter per second against

1824-748: The Great Leap Forward and the Cultural Revolution slowed progress. After the 1954 Yangtze River Floods , in 1956, Mao wrote " Swimming ", a poem about his fascination with a dam on the Yangtze River. In 1958, after the Hundred Flowers Campaign , some engineers who spoke out against the project were imprisoned. During China's emphasis on the Four Modernizations during its early period of Reform and Opening Up , The Communist Party revived plans for

1900-554: The Jingguang Railway was out of service for more than 100 days. The 1954 flood carried 50 cubic kilometres (12 cu mi) of water. The dam could only divert the water above Chenglingji, leaving 30 to 40 km (7.2 to 9.6 cu mi) to be diverted. The dam cannot protect against some of the large tributaries downstream, including the Xiang , Zishui , Yuanshui , Lishui , Hanshui , and Gan . In 1998,

1976-473: The Ministry of Environmental Protection , as of April 2007, more than 50 new plants could treat 1.84 million tonnes per day, 65% of the total need. About 32 landfills were added, which could handle 7,664.5 tonnes of solid waste every day. Over one billion tons of wastewater are released annually into the river, which was more likely to be swept away before the reservoir was created. This has left

2052-478: The National Development and Reform Commission , 366 grams of coal would produce 1 kWh of electricity during 2006. From 2003 to 2007, power production equaled that of 84 million tonnes of standard coal. Two hazards are uniquely identified with the dam: that sedimentation projections are not agreed upon, and that the dam sits on a seismic fault . At current levels, 80% of the land in

2128-543: The 1990s. This is largely due to China's large reforestation effort . This accelerated after the 1998 Yangtze River floods convinced the government that it should restore tree cover, especially in the Yangtze's basin upstream of the Three Gorges Dam. Concerns about the dam's impact on wildlife predate the National People's Congress's approval in 1992. This region has long been known for its rich biodiversity. It

2204-670: The Baihetan Hydro-generator units was completed in Harbin, where it both passed inspection and was awarded approval on October 27, 2018. The first 1,000 MW turbine runner was completed at Dongfang Electric's Baihetan Runner Processing Plant on January 12, 2019. The reservoir first started storing water on 7 April 2021, and by 24 April, the water storage elevation of the power station had risen over 720 metres. The hydropower station started partial electricity generation in July of

2280-521: The South China Grid has a capacity of 3,000 MW. The dam was expected to provide 10% of China's power. However, electricity demand has increased more quickly than previously projected. Even fully operational and despite its size, on average, it supported only about 1.7% of electricity demand in China in the year of 2011, when the Chinese electricity demand reached 4,692.8 TWh. According to

2356-625: The Three Gorges Dam Construction Fund, profits from the Gezhouba Dam , loans from the China Development Bank , loans from domestic and foreign commercial banks, corporate bonds , and revenue from both before and after the dam had become fully operational. Additional charges were assessed as follows: every province receiving power from the Three Gorges Dam had to pay an extra ¥7.00 per MWh, and

Baihetan Dam - Misplaced Pages Continue

2432-560: The Three Gorges Dam directly caused the extinction of the baiji. Of the 3,000 to 4,000 remaining critically endangered Siberian crane , many spend the winter in wetlands that the Three Gorges Dam will destroy. Populations of the Yangtze sturgeon are guaranteed to be "negatively affected" by the dam. In 2022 the Chinese paddlefish was declared extinct, with the last confirmed sighting in 2003. In 2005, NASA scientists calculated that

2508-470: The above equation and Ohm's law . 1   W = 1   V 2 / Ω = 1   A 2 ⋅ Ω , {\displaystyle \mathrm {1~W=1~V^{2}/\Omega =1~A^{2}{\cdot }\Omega } ,} where ohm ( Ω {\displaystyle \Omega } ) is the SI derived unit of electrical resistance . The watt

2584-433: The area is eroding, depositing about 40 million tons of sediment into the Yangtze annually. Because the flow is slower above the dam, much of this sediment settles there instead of flowing downstream, and there is less sediment downstream. The absence of silt downstream has three effects: Erosion in the reservoir, induced by rising water, causes frequent major landslides that have led to noticeable disturbance in

2660-519: The course of the dry season. During the South China floods in July 2010 , inflows at the Three Gorges Dam reached a peak of 70,000 m /s (2.5 million cu ft/s), exceeding the peak inflow during the 1998 Yangtze River floods . The dam's reservoir rose nearly 3 m (9.8 ft) in 24 hours and reduced the outflow to 40,000 m /s (1.4 million cu ft/s) in discharges downstream, preventing any significant impact on

2736-466: The dam and proposed to start construction in 1986. It emphasized the need to develop hydroelectric power. The Chinese People's Political Consultative Conference became a center of opposition to the proposed dam. It convened panels of experts who recommended delaying the project. The National People's Congress approved the dam in 1992: of 2,633 delegates, 1,767 voted in favour, 177 voted against, 664 abstained, and 25 members did not vote, giving

2812-422: The dam generated an average of 97.22 TWh of electricity per year, higher than Itaipu dam's average of 89.22 TWh of electricity per year during the same period. Due to the extensive 2020 monsoon season rainfall, the annual production reached ~112 TWh that year, which broke the previous world record of annual production by Itaipu Dam equal to ~103 TWh. The State Grid Corporation and China Southern Power Grid paid

2888-484: The dam is to control flooding, which is a major problem for the seasonal river of the Yangtze. Millions of people live downstream of the dam, with many large, important cities like Wuhan , Nanjing , and Shanghai located adjacent to the river. Large areas of farmland and China's most important industrial area are situated beside the river. The reservoir's flood storage capacity is 22 km (5.3  cu mi ; 18 million  acre⋅ft ). This capacity will reduce

2964-541: The dam site was done in 1992. In 2008, the original plan for the construction of Baihetan Hydropower Station, was formally started. In December 2008, the Baihetan site began construction. The dam was originally scheduled to be constructed between 2009 and 2018. The Jinsha River became officially closed in November 2014. Actual construction started on August 3, 2017. The manufacturing of the first water guiding mechanism in

3040-496: The dam was designed to increase the Yangtze River's shipping capacity. By providing flood storage space, the dam reduces the potential for flooding downstream, which historically plagued the Yangtze Plain . In 1931, floods on the river caused the deaths of up to 4 million people. As a result, China regards the project as a monumental social and economical success, with the design of state-of-the-art large turbines and

3116-512: The designed maximum level of 175 m (574 ft) by 2010. Made of concrete and steel, the dam is 2,335 m (2,554 yd; 1.451 mi) long and 185 m (607 ft) above sea level at its top. The project used 27.2 million m (35.6 million cu yd) of concrete (mainly for the dam wall), used 463,000 tonnes of steel (enough to build 63 Eiffel Towers ), and moved about 102.6 million m (134.2 million cu yd) of earth. The concrete dam wall

Baihetan Dam - Misplaced Pages Continue

3192-515: The energy company Ørsted A/S uses the unit megawatt for produced electrical power and the equivalent unit megajoule per second for delivered heating power in a combined heat and power station such as Avedøre Power Station . When describing alternating current (AC) electricity, another distinction is made between the watt and the volt-ampere . While these units are equivalent for simple resistive circuits , they differ when loads exhibit electrical reactance . Radio stations usually report

3268-445: The first time on October 26, 2010, in which the intended annual power-generation capacity of 84.7 TWh was realized. It has a combined generating capacity of 22.5 gigawatts and a designed annual generation capacity of 88.2 TWh. In 2012, the dam's 32 generating units generated a record 98.1 TWh of electricity, which accounts for 14% of China's total hydro generation. Between 2012 (first year with all 32 generating units operating) and 2021,

3344-420: The frequency of major downstream flooding from once every 10 years to once every 100 years. The dam is expected to minimize the effect of even a "super" flood. The river flooded in 1954 over an area of 193,000 km (74,500 sq mi), killing 33,169 people and forcing almost 18.9 million people to move. The flood waters covered Wuhan, a city of eight million people, for over three months, and

3420-402: The generator rotors have 80 poles. Rated power is 778 MVA , with a maximum of 840 MVA and a power factor of 0.9. The generator produces electrical power at 20  kV . The electricity generated is then stepped up to 500 kV for transmission at 50 Hz. The generator's stator , the biggest of its kind, is 3.1/3 m in height; the outer diameter of the stator is 21.4/20.9 m,

3496-454: The generators is 80.6 metres (264 ft). The flow rate varies between 600–950 cubic metres per second (21,000–34,000 cu ft/s) depending on the head available; the greater the head, the less water needed to reach full power. Three Gorges uses Francis turbines with a diameter of 9.7/10.4 m (VGS design/Alstom's design) and a rotation speed of 75 revolutions per minute. This means that in order to generate power at 50  Hz ,

3572-477: The inner diameter is 18.5/18.8 m, and the bearing load is 5,050/5,500 tonnes. Average efficiency is over 94%, with a maximum efficiency of 96.5% reached. The generators were manufactured by two joint ventures: Alstom , ABB , Kvaerner , and the Chinese company Harbin Motor; and Voith , General Electric , Siemens (abbreviated as VGS), and the Chinese company Oriental Motor. The technology transfer agreement

3648-472: The last main generator (No. 27) finished its final test on May 23, 2012, the six underground main generators were all operational, raising the capacity to 22.5 GW. After nine years of construction, installation and testing, the power plant was fully operational by July 2012. By August 16, 2011, the plant had generated 500 TWh of electricity. In July 2008 it generated 10.3 TWh of electricity, its first month over 10 TWh. On June 30, 2009, after

3724-435: The legislation an unusually low 67.75% approval rate. Construction started on December 14, 1994. The dam was expected to be fully operational in 2009, but additional projects, such as the underground power plant with six additional generators, delayed full operation until 2012. The ship lift was completed in 2015. The dam raised the water level in the reservoir to 172.5 m (566 ft) above sea level by 2008 and to

3800-501: The main dam was officially started. An opening ceremony took place on February 5, 2021, and storage of water behind the dam commenced on April 7 of the same year, and by April 24, the water storage elevation of the hydro plant had risen over 720 meters. On 20 December 2022, the formal completion of Baihetan Hydropower Station was achieved when the final hydro-generating unit was connected to the grid and began producing power. The facility generates power by utilizing 16 turbines , each with

3876-405: The main water turbines has a capacity of 700 MW. Combining the capacity of the dam's 32 main turbines with the two smaller generators (50 MW each) that provide power to the plant itself, the total electric generating capacity of the Three Gorges Dam is 22,500 MW. The last major component of the project, the ship lift, was completed in 2015. In addition to generating electricity,

SECTION 50

#1732766144525

3952-460: The maximum power output it can achieve at any point in time. A power station's annual energy output, however, would be recorded using units of energy (not power), typically gigawatt hours. Major energy production or consumption is often expressed as terawatt hours for a given period; often a calendar year or financial year. One terawatt hour of energy is equal to a sustained power delivery of one terawatt for one hour, or approximately 114 megawatts for

4028-503: The middle and lower river. The installation of ship locks is intended to increase river shipping from ten million to 100 million tonnes annually; as a result transportation costs will be cut between 30 and 37%. Shipping will become safer, since the gorges are notoriously dangerous to navigate. There are two series of ship locks installed near the dam ( 30°50′12″N 111°1′10″E  /  30.83667°N 111.01944°E  / 30.83667; 111.01944 ). Each of them

4104-509: The other provinces had to pay an additional charge of ¥4.00 per MWh. No surcharge was imposed on the Tibet Autonomous Region . Power generation is managed by China Yangtze Power , a listed subsidiary of China Three Gorges Corporation (CTGC), a Central Enterprise administered by SASAC . The Three Gorges Dam is the world's largest capacity hydroelectric power station, with 34 generators: 32 main generators, each with

4180-488: The power of their transmitters in units of watts, referring to the effective radiated power . This refers to the power that a half-wave dipole antenna would need to radiate to match the intensity of the transmitter's main lobe . The terms power and energy are closely related but distinct physical quantities. Power is the rate at which energy is generated or consumed and hence is measured in units (e.g. watts) that represent energy per unit time . For example, when

4256-585: The reservoir flooded a total area of 632 km (156,000 acres) of land, compared to the 1,350 km (330,000 acres) of reservoir created by the Itaipu Dam . The Chinese government estimated that the Three Gorges Dam project would cost 180 billion yuan (US$ 22.5 billion). By the end of 2008, spending had reached 148.365 billion yuan, of which 64.613 billion yuan was spent on construction, 68.557 billion yuan on relocating affected residents, and 15.195 billion yuan on financing. It

4332-511: The reservoir surface, including two incidents in May 2009 when somewhere between 20,000 and 50,000 cubic metres (26,000 and 65,000 cu yd) of material plunged into the flooded Wuxia Gorge of the Wu River . In the first four months of 2010, there were 97 significant landslides. The dam catalyzed improved upstream wastewater treatment around Chongqing and its suburban areas. According to

4408-401: The river basin. After the extensive monsoon rainfalls of 2020, the dam's annual production reached nearly 112 TWh, breaking the previous world record of ~103 TWh set by Itaipu Dam in 2016. The dam's body was completed in 2006; the power plant was completed and fully operational by 2012, when the last of the main water turbines in the underground plant began production. Each of

4484-458: The river downstream, providing fresh water for agricultural and industrial usage, and improving shipping conditions. The water level upstream drops from 175 to 145 m (574 to 476 ft), in preparation for the rainy season. The water also powers the Gezhouba Dam downstream. Since the filling of the reservoir in 2003, the Three Gorges Dam has supplied an extra 11 km (2.6 cu mi) of fresh water to downstream cities and farms over

4560-419: The river flow rate increased to over 24,000 m /s, all 28 generators were switched on, producing only 16,100 MW because the head available during flood season is insufficient. During an August 2009 flood, the plant first reached its maximum output for a short period. During the November to May dry season, power output is limited by the river's flow rate, as seen in the diagrams on the right. When there

4636-469: The same year. The dam was expected to be fully operational by July 2022. Experts have noted the 4-year construction period as being exceptionally fast for a project of its type. On June 28, 2021, the Baihetan Dam began generating electricity, when the project's first two turbines started operating. The third turbine followed in July and the fourth in November of the same year. The final generating unit

SECTION 60

#1732766144525

4712-535: The shift of water mass stored by the dams would increase the total length of the Earth 's day by 0.06 microseconds and make the Earth slightly more round in the middle and flat on the poles . A study published in 2022 in the journal Open Geosciences suggests that the change of reservoir water level affects the gravity field in western Sichuan, which in turn affects the seismicity in that area. An important function of

4788-569: The unit of power. In the electric power industry , megawatt electrical ( MWe or MW e ) refers by convention to the electric power produced by a generator, while megawatt thermal or thermal megawatt (MWt, MW t , or MWth, MW th ) refers to thermal power produced by the plant. For example, the Embalse nuclear power plant in Argentina uses a fission reactor to generate 2,109 MW t (i.e. heat), which creates steam to drive

4864-570: The unit within the existing system of practical units as "the power conveyed by a current of an Ampère through the difference of potential of a Volt". In October 1908, at the International Conference on Electric Units and Standards in London, so-called international definitions were established for practical electrical units. Siemens' definition was adopted as the international watt. (Also used: 1 A × 1 Ω.) The watt

4940-399: The upper gate of the chamber below and the lower gate of the chamber above. The gates are the vulnerable hinged type, which, if damaged, could temporarily render the entire flight unusable. As there are separate sets of locks for upstream and downstream traffic, this system is more water efficient than bi-directional staircase locks. In addition to the canal locks, there is a ship lift ,

5016-415: The upstream water level from 145.13 m (476.1 ft) on August 1, to 152.88 m (501.6 ft) on August 8. A full 4.27 km (1.02 cu mi) of flood water was captured and the river flow was cut by as much as 15,000 m (530,000 cu ft) per second. The dam discharges its reservoir during the dry season every year, between December and March. This increases the flow rate of

5092-549: The water stagnant, polluted and murky. In 1997, the Three Gorges area had 10% forestation, down from 20% in the 1950s. Research by the United Nations Food and Agriculture Organization suggested that the Asia-Pacific region would gain about 6,000 km (2,300 sq mi) of forest by 2008. That is a significant change from the 13,000 km (5,000 sq mi) net loss of forest each year in

5168-483: The water temperature and flow regime. Many other fish are injured in the hydroelectric plants' turbine blades. This is particularly detrimental to the region's ecosystem because the Yangtze River basin is home to 361 different fish species and accounts for 27% of China's endangered freshwater fish species. Other aquatic species have been endangered by the dam, particularly the baiji, or Chinese river dolphin , now extinct. In fact, Chinese Government scholars even claim that

5244-589: Was conducted at Qiaojia by a domestic expert group and a Czechoslovakian expert group and, consequently, the future site for the Baihetan Power Station was selected. However, the breaking down of relations during the Sino-Soviet split in 1962, resulted in the survey team being withdrawn. The beginning of China's “Cultural Revolution" also saw the construction plans becoming shelved for many years. It wasn't until August 3, 2017, when construction of

5320-523: Was connected to the grid on 20 December 2022. The dam and reservoir have particularly affected upstream Qiaojia County , providing thousands of jobs to local residents, while also requiring resettlement of 32 villages totaling 50,178 residents. Coinciding with the dam construction, the road network was also improved. Three Gorges Dam This is an accepted version of this page The Three Gorges Dam ( simplified Chinese : 三峡大坝 ; traditional Chinese : 三峽大壩 ; pinyin : Sānxiá Dàbà )

5396-584: Was considered for its water-saving performance or because the engineers thought the difference in height between the river above and below the dam too great for alternative methods. No construction work was performed because of the Nationalists' worsening situation in the Chinese Civil War. After the 1949 Communist Revolution , Mao Zedong supported the project, but began the Gezhouba Dam project nearby first, and economic problems including

5472-420: Was defined as equal to 10 units of power in the practical system of units. The "international units" were dominant from 1909 until 1948. After the 9th General Conference on Weights and Measures in 1948, the international watt was redefined from practical units to absolute units (i.e., using only length, mass, and time). Concretely, this meant that 1 watt was defined as the quantity of energy transferred in

5548-407: Was estimated in 2009 that the cost of construction would be fully recouped when the dam had generated 1,000 terawatt-hours (3,600 PJ) of electricity, yielding 250 billion yuan; total cost recovery was thus expected to be completed ten years after the dam became fully operational. In fact, the entire cost of the Three Gorges Dam was recovered by December 20, 2013. Funding sources include

5624-438: Was eventually achieved on October 18, 2006, after the water level reached 156 meters. On the south side, main generator No. 22 started up on June 11, 2007, and No. 15 became operational on October 30, 2008. The sixth (No. 17) began operation on December 18, 2007, raising capacity to 14.1 GW, exceeding that of Itaipu dam (14.0 GW) to become the world's largest hydro power plant by capacity. When

5700-611: Was possible downstream of the Three Gorges . In 1932, the Nationalist government , led by Chiang Kai-shek , began preliminary work on plans in the Three Gorges. In 1939, during the Second Sino-Japanese War , Japanese military forces occupied Yichang and surveyed the area. In 1944, the United States Bureau of Reclamation 's head design engineer, John L. Savage , surveyed the area and drew up

5776-412: Was signed together with the contract. Most of the generators are water-cooled. Some of the newer ones are air-cooled, making them simpler in design and easier to manufacture and maintain. The first north-side main generator (No. 2) started up on July 10, 2003. The north side became completely operational on September 7, 2005, with the implementation of generator No. 9. Full power (9,800 MW)

#524475