The 10-year power purchase agreement that Tri-State’s board of directors authorized in August 2012 is expected to come to fruition this spring when the Tri-County Water Hydropower Project begins producing power on June 1 for the G&T from its newly constructed hydroelectric generation plant at the Ridgway Dam and Reservoir in Ouray County, Colo.
The new hydroplant features two generating units – a 7.2-megawatt generator and a smaller 800-kilowatt unit – that will produce up to 8 megawatts of capacity and approximately 24 gigawatt-hours of energy during an average water year.
Under the terms of the agreement with Tri-County Water Conservancy District, Tri-State will purchase power from the Ridgway facility during the months of June, July, August and September and the City of Aspen will buy the power produced at this facility during the other eight months of the year. Despite the shorter seasonal duration for Tri-State, these are typically the year’s higher output months and the association estimates that it will receive about 60 percent of the plant’s annual generation output.
The Tri-County Water Hydropower Project is within the service territory of Tri-State member, San Miguel Power Association (Nucla, Colo.) and is receiving station electric service from the co-op.
To interconnect the new generating facility to the power grid, Tri-State completed the 115-kV Cow Creek Switching Station and added an approximately 1-mile 115-kV transmission line to the dam site in the fall of 2013.
According to a recent article in the Telluride Watch, work on the plant’s power house was nearly complete at the end of February and generator testing was underway on the small 800-kilowatt unit. “The big generator should be ready for testing by April,” said Mike Berry of Tri-County Water Conservancy District.
Ridgway Dam and Reservoir are part of the Dallas Creek Project that was authorized in 1968 under the Colorado River Storage Project Act of 1956. Ridgway Dam was built in 1987 and Ridgway Reservoir was filled in 1990. The reservoir, which was designed to provide flood control, supplemental irrigation water and water for municipal and industrial uses, is fed by the Uncompahgre River.