Bieudron power station

Bieudron power station-The world's highest water head hydroelectric Plant

today, let me introduce the world's highest water head hydropower station to every one. it's name is "Bieudron power station".

The Bieudron Hydroelectric Power Station is a hydroelectric power plant located in the Swiss Alps in the Canton of Valais in Switzerland. The power plant is fed with water from the Grande Dixence Dam's reservoir, Lac des Dix and is part of the Cleuson-Dixence Complex. The 1269 MW power plant is operated by Grande Dixence SA.

The Bieudron power station alone holds three world records, for the height of its head (1883 m), the output of each Pelton turbine (3 x 423 MW) and the output per pole of the generators (35.7 MVA).

Bieudron hydropower station unit parameter
item	unit	value
Max. Water head	m	1883
Each capacity	MW	420
Water turbine type		Pelton
speed	r/min	428.6
Rated flow	m3/s	75
Turbine runner diameter	m	4.65
Turbine weight	t	120
nozzles exit flow velocity	km/h	690
generator rated capacity	MVA	465
Rated voltage	kV	21(±10%)
Rated frequency	Hz	50
Generator stator weight	t	281
Generator rotor weight	t	454
Installation capacity of power plant		3×420MW
total investment	billion dollar	0.8
《ABB Review》1994，No.10。

This facility houses three Pelton turbines, with each turbine rated at 423 MW (~567,000 HP); note that the turbine acceptance testing process reported a maximum turbine output power of 449 MW each (~602,000 HP) due to better than expected efficiency and ideal test conditions.[1]

At the rated power of 423 MW each turbine operates at a head of ~1869 meters (6130 feet) and a flow rate of 25 cubic meters per second, with an efficiency in excess of 92% (~92.37%). The turbine assembly is a five-jet configuration; the stream of each jet is 193 mm (7.6 inches) in diameter with an exit velocity of 192 meters/second (630 ft/s). The kinetic energy of each of the 5 streams (i.e. 1 from each jet) is approximately 92.16 MW (Q = 5 cubic meters per second, v = 192 m/s, H = 1869 m). The assembly rated pressure is 203.2 bars (2944 psi).

The combined flow rate for the three turbines is 75 cubic meters per second. The facility peak power production is ~1269 MW. The turbines and associated valves were designed and developed by VA Tech of Switzerland.

On December 12, 2000, at approximately 20:10, the Cleuson-Dixence penstock, feeding the Pelton turbines at Bieudron, ruptured at ~1234 meters AMSL (under more than 1000 meters of head). The failure appears to have been due to several factors including the poor strength of rock surrounding the penstock at the rupture location. The rupture was approximately 9 m long by 60 cm wide. The flow rate through the rupture was likely well in excess of 150 m3/s (5,300 cu ft/s). The ensuing rapid release of a very large quantity of high pressure water destroyed approximately 100 hectares (1 km²) of pastures, orchards, forest, as well as washing away several chalets and barns around Nendaz and Fey. Three people were killed.[2]

The Bieudron facility was inoperative after the accident; however, it became partially operational in December 2009, and fully operational in January 2010. Much investigation went into the accident resulting in the almost complete redesign of the penstock. Legal action is still in process and the root cause of the rupture is unknown.

However details regarding the redesign are available. The redesign calls for improvements in the pipe's lining as well as the addition of grouting around the penstock to reduce water flow between the penstock and the surrounding rock due to dynamic variation of the pipe diameter during operation (it expands due to water loading during operation then contracts when the load is removed, leaving a gap). The damaged section of the penstock was rerouted around the previous location to where new (undamaged) more stable rock is available. Construction on the redesigned penstock was completed in 2009. Redesign considerations include operational control of maximum agreed design limits under all conditions of assembly, design and service conditions (including water hammer pressure spikes).

https://en.wikipedia.org/wiki/Bieudron_Hydroelectric_Power_Station

XIANGJIABA hydropower station

Xiangjiaba hydropower station

China's third largest hydropower station

-XIANGJIABA  hydropower station

Project total investment:43.4 Billion Yuan

 Engineering period: 2008-2015

Xiangjiaba hydropower station located in downstream of Jinsha river, Yuannan Fushui county (right bank) and Sichuan Yibin County (Left Bank) . Where is the junction of the two provinces. 157km away from Xiluodu hydropower station. Static investment 43.4 billion Yuan.

Xiangjiaba hydropower station installation capacity 6000 megawatt,( total 8 unit, each one 750 megawatt), reservoir normal storage water level 380m,guarantee output power 2.009 million KW, average annual generating capacity of 30.747 billion KWH. reservoir area 95.6 sq.km, the reservoir is gorge type, total reservoir volume 5.163billion cubic meter. Backwater length 156.6 km. control drainage area 458.8 thousand sq.km. 97% of Jinsha river drainage area.

The project closure on 2008, and the first unit put into operation on 2012, complete project finished on July.2014.

The project use gravity dam, crest elevation 383m, crest length 909.3m, max. Dam height 161m.

Xiangjiaba hydropower station also use vertical Francis hydro turbine, installed 8 unit 800MW turbine generator set. it has the world largest unit installed capacity Francis turbine generator, also the first 800MW Francis turbine generator in the world.

The turbine key parameter below:(world's largest hydro turbine)

Installed capacity:8x800MW,

Max. Water head: 114.2m,

Min.water head:86.1m,

Rated water head: 100m

Runner inlet diameter:10360mm

Runner outlet diameter: 9300mm

Runner max. Diameter:10527mm

Rated output power:812MW

Turbine rated speed:71.4r/min

XILUODU hydropower station

China's second largest hydropower station

-XILUODU hydropower station

Project total investment:79.2 Billion Yuan
Engineering period: 2005-2015

Xiluodu hydropower station is located in Qinghai-Tibet Plateau, Yunnan-Guizhou Plateau to the Sichuan Basin transition zone, located in Xiluodu Gorge, where bordering Leibo County, Sichuan Province and Yongshan County, Yunnan Province,  Xiluodu Hydropower Station is the largest of the four giant hydropower station on Jinsha River, Capacity quite with the Itaipu,the world's second largest hydropower station.total installed capacity is 12.6 million kilowatts, Annual generation capacity ranked third in the world,is 571.2 billion KWh, equal to Itaipu hydropower station, and three and a half of the Gezhou Dam, is the second largest hydropower station in China.

Xiluodu hydropower station is the closest key power of China “west to east power transmission project” on Jinsha river, also the largest hydropower station on Jinsha river.

Jinsha river is upper stream of Yangtze river,total length 3364 kilometer, drainage area 473.2 thousand sq.km. Jinsha river has abundant water resources, reserves energy reached 112.4 million kilowatts,  accounted for 1/6 of the total hydropower in China.

This project located in Xiluodu Gorge, where bordering Leibo County, Sichuan Province and Yongshan County, Yunnan Province, downstream of Jinsha river. The project use concrete double curvature arch dam,dam height 278m, normal storage water level 600m, total storage 11.57 billion cubic meters,

Regulation storage 6.46 billion cubic meters, installed capacity 12.6 million KW, average annual generating capacity of 57.12 billion KWH, the project static investment 45.928 billion Yuan, total 79.234 billion Yuan. Project feasibility design finished on Dec. 2001, start building on Dec.2005, on Jun.2013, the first set of generator put into operation, and whole project completed on 2015.

Xiluodu Hydropower station use vertical Francis hydro turbine, manufacturer Voith, rated water head 197m, max. Head 229.4m, min. Head 154.6m, weighted average of the head 223.48m, rated flow 430.5 cubic meter per second, rated output power 784 Megawatt, rated speed 125 r/min,suction head HS=-10.81m, installation elevation 359m. Francis runner diameter is 7.4m, max. Outer diameter 7.755m, height 3.462m, each runner weight 179 ton.

Material is stainless steel 0Cr13Ni4Mo.  

  

When Xiluodu hydropower plant was fully connected to the grid in June 2014, it started with a nominal capacity of 13.86 gigawatts. All in all, 18 machine units are in operation. This made it the world's third largest hydropower plant. The plant will help to reduce air pollution thanks to the renewable electricity production of Xiluodu: The annual consumption of coal will be cut down by 41 million tons. In addition to that, exhaust gas emissions will be reduced by nearly 150 million tons of CO2, 480,000 tons of nitrogen dioxide and 850,000 tons of sulfur dioxide per year.

Another advantage of Xiluodu is the ability to deliver base load in large quantity. Xiluodu can produce as much energy around the clock as 14 large thermal or nuclear power plants. As a matter of fact, hydropower technology can bridge the gap between the enormous demand of electricity, and, on the other hand, meet the emission targets our societies have committed themselves to.

panoramic photo of Construction site:

Closure photo of the Xiluodu Dam

Dam photo:

 Spiral case photo:

 spiral case welding:

 Draft tube tunnel construction

 spiral case installation

 Francis turbine runner

 generator rotor isntallation

 generator stator assembly

night scene of XILUODU

Three Gorges Hydropower Project

In 2012, the Three Gorges Dam in China took over the #1 spot of the largest hydroelectric dam (in electricity production), replacing the Itaipu hydroelectric power plant in Brazil and Paraguay. The Three Gorges Dam has a generating capacity of 22,500 megawatts (MW) compared to 14,000 MW for the Itaipu Dam. But, over a year-long period, both dams can generate about the same amount of electricity because seasonal variations in water availability on the Yangtze River in China limit power generation at Three Gorges for a number of months during the year.

The height of Three Gorges is about 594 feet (181 meters (m)) and the length is about 7,770 feet (2, 335 m). The dam creates the Three Gorges Reservoir, which has a surface area of about 400 square miles (1,045 square kilometers) and extends upstream from the dam about 370 miles (600 kilometers).

In the United States, the Grand Coulee Dam on the Columbia River, Washington, is the largest, with a generating capacity of about 6,800 MW (5th overall worldwide).

Three Gorges power station had installed 32 units of 700MW turbines,which is the largest capacity, largest size of Francis generator set. The Francis turbine runner diameter is 10.05m,height 5.99m, total weight 445 ton, 15 blades, each blades weight 17.6 ton. The runner use stainless steel 0Cr13Ni4Mo, weld structure. The turbine design water head 85m.