CR December / January 2010

Massive Caruachi Hydro Power Plant a Boost to Venezuelan Economy

The colossal multi-million power plant now saves Venezuela the equivalent of 750,000 barrels of oil per day, allowing the oil industry to considerably raise valuable export sales

The massive Caruachi hydroelectric power facility is located on the Caroní River, in Bolivar state, Venezuela. The facility is located about 59 kilometers downstream from the Lake of the "Central Hidroeléctrica Simón Bolívar" in Guri and about 35 kilometres from where the Caroni and Orinoco Rivers meet at Ciudad Guayana.

Introduction

The first of the 180 MW Kaplan turbine-generators General Electric supplied for the project began commercial operation in April of 2003. The 12th and final unit entered service on February 28, 2006, and entered into formal/fully commercial operation on March 31, 2006; when the project was officially inaugurated.

The total installed capacity is 2,160 MW and the power plant will produce about 12,000GWh annually. This project form jointly with the Central Hidroeléctrica Simón Bolívar in Guri, Antonio José de Sucre in Macagua and Manuel Piar in Tocoma (under construction), the development of Lower Caroní hydroelectric resources, one of the world's largest hydro projects now in construction. Design and Construction

The contract for the design, supply and installation of the main electro-mechanical equipment was awarded to a consortium of Kvaerner of Norway (Kvaerner's hydro interests since acquired by GE), GE Energy of America and Elin Transormatoren GmbH of Austria. Major work began on the project in 1998. ABB won three contracts to provide the power transmission system for the project. A 400kV substation and four related 400kV transmission lines connect the plant with the country's transmission network.

Project Features

A main concrete 360-metre gravity dam has a maximum height of 55 metres from its foundations, with an integrated intake structure and powerhouse. A 900-metre right-abutment rockfill closure dam has a concrete slab face and a maximum height of 50 metres, and a 4,200-metre left-abutment earth and rockfill closure dam has a maximum height of 45 metres.

A spillway with nine spans and radial surface gates has an aggregate 30,000 cubic metres per second flow capacity. A 470-metre powerhouse is integrated with the main dam with space for 12 generating units (360 metres) and an assembly bay (110 metres). Two transition dams have a 50-metre intermediate buttress between the powerhouse and spillway. The 238 sq. km reservoir has a 91-metre normal operating head.

The first two turbine-generators entered commercial service at the Caruachi hydroelectric plant in August 2003. Unit one was on schedule and unit two came on line a month ahead of the contract completion date. Today, the power plant produces about 12,000GWh annually, boosting Venezuela's total generating capacity by around 11 per cent. The plant site is 500km from Caracas on the lower reaches of the Caroní River in Bolivar state, where Electrificación del Caroní CA (EDELCA) has concentrated its investments... Overall investment for the Caruachi project is estimated at $2.1 billion.

Project Sponsor

The project sponsor was EDELCA, that is part of state metals group Corporación Venezolana de Guayana (CVG). The investment provides an important addition to the significant capacity that EDELCA runs along the Caroní river in southeastern Venezuela. The Caruachi project is the third hydroelectric complex undertaken by EDELCA. No doubt, one of the world's latest largest hydro projects recently constructed, the project has been a major economic boost to Venuzuela’s economy which heavily relies on oil.

The Caroni River is already the country's main power source - plants along it, including the massive 10,000MW Guri plant completed in the 1980s, cover almost three quarters of demand. With the completion of the Caruachi Project, EDELCA now claims that harnessing the Caroní saves Venezuela the equivalent of 750,000 barrels of oil per day, compared to 300,000 previously. This allows the oil industry to considerably raise valuable export sales. GE Supplied Turbine Generators

The US$500 million contract for design, supply and installation of the main electro-mechanical plant went to a consortium of Kvaerner of Norway, GE Canada and Elin Transormatoren GmbH of Austria. Following GE's acquisition of Kvaerner's hydro business in 1999, over 90 per cent of the Caruachi contract was carried out by GE Hydro, including all aspects of the design, supply and installation of the turbines, generators, governors, exciters and cranes. The 180MW Kaplan turbine-generators are among 12 GE Hydro units for the Caruachi project. Consortium partners supplied power transformers and ancillary equipment.

"The Caruachi project is one of the world's largest hydro projects to be brought online over the past few years, and is an excellent example of GE's total project capability," said Mike Conway, general manager of GE Energy's hydro business. "The design and supply of the equipment involved GE facilities in Canada, Norway, Sweden, Finland and the U.K. GE also provided project management and installation, and supported the project by helping to arrange the financing through European and Canadian export credit agencies. GE Energy's hydro team is proud to have been selected by C.V.G. EDLECA to support this important project, and looks forward to continuing the relationship we have developed over the past eight years."

Substation and Transmission Lines

ABB won three contracts worth US$41 million to provide the power transmission system for the project. A 400kV substation and four related 400kV transmission lines connect the plant with the country's transmission network. The project also included all high-voltage equipment, associated switchyard equipment and computerised protection and control equipment. ABB was also responsible for all electrical and mechanical design for the substation and civil work, erection and commissioning for both contracts.