Power Engineering magazine recognized the 2010 Projects of the Year Award finalists and announced the winners. The Tekeze hydro project in Ethiopia won the Project of the Year Award for the renewable/sustainable project category.
The winners were announced at the POWER-GEN International conference and exhibition in Orlando, Fla.
This year's Projects of the Year Award winners and honorable mentions produced facilities and/or technologies that ushered in breakthrough solutions in four categories: coal-fired, gas-fired, nuclear and renewable/sustainable.
The Tekeze hydropower project is located on the Tekeze River, a tributary of the Nile. The $350 million project, funded by the government of Ethiopia and owned by Ethiopian Electric Power Corp., adds 40 percent more energy to the country and was the largest public works project in Ethiopia's history at the time of construction. Due to the lack of natural resources and the cost of imported fuels, power generation in Ethiopia comes primarily from hydroelectric sources.
The Tekeze project includes the tallest arch dam in Africa at 188 meters. The dam is a double curvature concrete arch dam, a method of design that minimizes the amount of concrete used, creating a reservoir 70 kilometers in length. An underground powerhouse, containing four 75 MW Francis Turbines, is located approximately 500 meters downstream of the dam and fed by a 75-meter-high intake structure connected by a 500-meter-long concrete-lined power tunnel. A 230 kV double-circuit transmission line 105 kilometers long was constructed through mountainous terrain to connect to the Ethiopian national grid.
The project's beginnings date back to 1995 when the Ethiopian Ministry of Water Resources conducted a study identifying the site as one of two preferred dam sites for hydropower development. MWH joined the project in 1998 and made modifications to an existing design for the dam, powerhouse and tunnel system, resulting in cost savings.
A multi-stage impoundment approach was implemented during construction, which allowed the river diversion to be closed in May 2007, nearly two years prior to dam completion. This allowed for more than 3 Bm3 of water to be retained, advancing generation by more than one full year. The value of the water captured via early impoundment was worth approximately $40 million. In addition to power generation, the Tekeze dam enables regulation of river flow, allowing downstream communities year-round access to the water supply.
For more hydropower news and information, click here