310 likes | 510 Views
Three Gorges Dam Highlights. Important Dates. In 1918, Mr. Sun Yat-Sien suggested that “a dam should be built to let ships go downstream and use the water resource as power.”
E N D
Important Dates • In 1918, Mr. Sun Yat-Sien suggested that “a dam should be built to let ships go downstream and use the water resource as power.” • In May 1945, Dr. John Savage, invited by the Chinese Government, investigated the Three Gorges and put forward his Preliminary Report on Three Gorges Development Plan. • In 1971, construction of the Gezhouba Dam was initiated downstream of the Three Gorges; it started generating power in 1981 and was completed in 1988. • On 29 July 1993, the Report of the Design of the Three Gorges Project was approved by the National Congress. • On 14 Dec 1994, the Three Gorges project officially started and was completed in 2008.
Amount of Work • Rock-and-earth excavation of 103 million m3 • Concrete placement of 28 million m3 • Metal frame installation of 256,500 tons • Installation of twenty-six 700 MW turbine-generator units
Benefits of the Dam 1. Flood Control 2. Power Generation 3. Navigation
Power Generation: 84.7 Terawatt Hours (TWH)(each TWH=One Trillion Watthours)
Navigation • Backwater of the TG reservoir goes as far west as Chongqing, greatly improving 660 km of waterway, and enabling10,000 tonnage ships to navigate between Shanghai and Chongqing. • The annual one-way navigation capacity of the Three Gorges will be upgraded from ten million tons to fifty million tons, with the cost reduced by35%.
Why Was Dam Built in this Site? 1. Zhongbao Island 2. Wide river bed 3. Perfect river curve 4. Dam site on ideal granite belt 5. Complete rock body for the construction of the Dam 6. Good geological conditions to ensure Dam safety
Double Way five step Shiplocks • 5 stages & 2 channels • 280M X 34M (918Ft X 111Ft)/chamber • Total draft 113M (370Ft), 22.6M (74Ft)/stage • 4 hours to go through • 10,000 ton fleet
SHIP ELEVATOR • 3,000 ton ship • Total weight lifting 11,800 tons (container 2,800 tons, water & ship 9,000 tons) • Preliminary design using steel cables
Western Technology Joint Venture 1 (generators) • Alstom, France • ABB, Switzerland • Kvaerner, Norway Joint Venture 2 (generators) • Voith, Germany • GE, Canada • Siemens – Germany Other Equipment Caterpillar
Financing of the project 1. Chinese consumers were charged 0.4 cent for every KW/H from 1993 on 2. Profits from the older Gezhouba Dam 3. Earnings of the TGP which started generating power from 2003 on 4. Loans from the China Development Bank (CDB) 5. Three international bond issues of CDB 6. Private sector investments of industrialized countries with the sovereign guaranty of CDB
Adverse Effect of the TGD • Sedimentation • The TGP inundated 632 k㎡ of land, including 24,500hectares of farmland and citrus land • 19 cities and 326 towns partially or totally submerged • More than one million people have been relocated already, several more million will be relocated in the next 10-15 years • Many ancient relics & archeological sites submerged
Sediment • 530 million tons of sediment (e.g., gravel, sand and other coarse material) pass annually through the dam. • TGD has been flushing away higher sediment by releasing floodwater through gates at the bottom of the dam between June and September (peak period of floods). • High rate of sediment deposit will compromise the operation of the dam