22 July 2002 – The U.S. Department of the Interior’s Bureau of Reclamation has awarded GE Power Systems a $3.8 million contract for a generator refurbishment project at the Grand Coulee power plant in Washington State.
Located at Grand Coulee Dam on the Columbia River in central Washington, the Grand Coulee hydroelectric power plant is the largest power production facility in North America, generating an average of 21 billion kWh annually. It consists of three power plants – the Left, Right and Third – that supply electricity to the Pacific Northwest.
GE will supply two identical 125 MVA, 13.8 kV generator stator cores and windings for the refurbishment project. One stator core will be installed and commissioned by GE at the Left Powerhouse G7 unit. The second generator core is planned for future installation at another powerhouse unit.
This project represents the first use of a modern-design, single-turn bar winding at Grand Coulee Left Powerhouse and is expected to significantly improve generator reliability and maintainability. GE’s Twintone-insulated bar windings will replace the stator’s present coil windings. Used by GE for over 30 years, this system provides a better mechanical fit in the stator slots than multi-turn coil windings, thereby avoiding loose windings.
The GE Twintone bar windings use more copper, which improves efficiency and reduces operating temperatures for longer winding life. Bar winding repair is simpler and faster than for coil windings because in the event of failure, only a few bars at most need to be removed to access the failed bar. Multi-turn coil replacement requires more time-consuming removal of a large portion of the winding.
The equipment will be built at GE Hydro in Lachine, Quebec, Canada, and will begin shipping to site in January, 2003. Installation by GE Installation and Repair Service of Salt Lake City, Utah, is expected to be completed by the start of the third quarter 2003. The unit is scheduled to be returned to commercial operation in February, 2004.
In another, concurrent project at Grand Coulee for the Bureau of Reclamation, GE is also replacing 18 Francis turbine runners at the Left and Right powerhouses. This project is scheduled for completion in 2007.
The Grand Coulee Dam, the centerpiece of the Columbia Basin project begun in 1934, was completed in 1942. The Left and Right powerhouses, with nine generator units each, were put into service between 1941 and 1950. The hydropower plants are used as peaking facilities by the Bonneville Power Administration.
The Bureau of Reclamation is the second largest producer of hydroelectric power in the U.S., with 58 hydropower plants – all located in the western U.S. – and an installed capacity of more than 14.7 million kW. GE Hydro, a division of GE Power Systems, is a world leader in the supply of turbines, generators, and water systems for the hydropower and water control industries.
Capabilities include complete water to wire solutions for new plants, and refurbishment and service for existing plants.
About GE Power Systems
GE Power Systems (www.gepower.com) is a supplier of power generation technology, energy services and management systems, with 2001 revenues exceeding $20 billion. GE Power Systems provides equipment, services and management solutions across the power generation, oil and gas, distributed power and energy rental industries.