PWC has the distinction of being the only municipal utility company in North Carolina to own and operate a power plant. The Butler-Warner Generation Plant is designed to keep customers’ rates competitive because it provides power during peak consumption hours, when purchasing electricity from outside sources is more expensive. The plant was named in honor of Robert H. Butler and James R. Warner, former chairmen of the Commission.
Between 1976 and 1980, PWC installed eight peak-shaving gas turbine generators capable of producing a maximum of 192 megawatts (MW) of electricity. In 1988, six of these units were converted to a combined-cycle steam mode which increased generating capacity of the plant by approximately 65 MW, to a total maximum of 265 MW of generating capacity.
In 1993, a thermal energy storage (ice storage) system was added to the plant for cooling the gas turbines in the summer peak season. When in operation, this system offsets the reduction in capacity that comes with the higher summer temperatures and enables the plant to generate at its maximum capacity even during the hottest summer period. This is one of the largest thermal energy storage plants in the world with 4.6 million gallons of ice storage capacity and has attracted worldwide attention because it can cost-effectively increase the plant’s summer capacity by almost 20%.
In all, the plant’s generating capacity is approximately 265 MW.
Location: Custer Road, northeast Cumberland County
Built: Initial Installation: 1976
Major Upgrade: 1988, 1992
Generation Capacity: 265,000 kW
Features: 8 G.E. Turbines (25,000 kW) each; 65,000 kW Steam Turbine; One of the world's Largest Thermal Energy Storage projects. Makes 2,560 tons of ice per day, is used to cool air entering the turbines that generate electricity.
Summer System Peak Demand: 476.6 MW (Aug. 9, 2007)
Winter System Peak Demand: 433.7 MW (Dec. 15, 2010)
Distinctions: Included on list of "Plants to See" by the World Energy Conference and American Public Power Association