Rolling Hills Generating LLC applied June 1 at the Ohio Power Siting Board for an amendment to a Certificate of Environmental Compatibility and Public Need, which would allow the conversion of the existing Rolling Hills Generating Station from a simple-cycle combustion turbine facility to a combined-cycle combustion turbine facility.
For the conversion, four of the existing five simple-cycle turbines will be converted into two, 2×1 combined-cycle power blocks, leaving one unit in simple-cycle operation. This will require installing four new Heat Recovery Steam Generators (HRSGs) each equipped with 550 Million British Thermal Unit per hour (MMBtu/hr) duct burners, two new steam turbines, two new cooling towers, and associated equipment. The existing high-performance combustion turbine-generators will be unmodified and continue to be fueled with natural gas only.
The converted facility will be constructed within the existing site, which is owned by Rolling Hills. The site consists of three parcels of land totaling approximately 182 acres, located near the intersection of State Routes 160 and 689, north of Wilkesville, Ohio, in Vinton County.
This facility currently operates as a peaking power plant, primarily on warm summer days. After the conversion, the combined-cycle power blocks will serve intermediate loads or baseload power demands, with the remaining simple-cycle unit used to provide electric peaking power to the wholesale power market in Ohio and the surrounding region.
The converted facility will be constructed, owned and operated by Rolling Hills, a special purpose subsidiary of TPF II LP. Headquartered in Omaha, Neb., TPF II LP is a private equity firm focused on investments in the power and energy sectors in North America. TPF II LP is managed by Tenaska Capital Management LLC.
Under the current configuration, this plant is an approximately 860-MW (net) facility consisting of five Siemens 501FD2 natural gas-fired combustion turbine generators, operating in simple-cycle mode. Upon completion of the conversion, two 2×1 combined-cycle power blocks will be capable of each producing an average nominal net output of 621 MW, for a total of 1,242 MW of combined-cycle capacity. The single combustion turbine that remains in simple-cycle mode will still be capable of producing an average nominal net output of 172 MW. The total nominal output after conversion will be about 1,414 MW (net).
Pending board approval of this revised siting certificate, construction is anticipated to begin in the first quarter of 2014, with commercial operation of the converted facility expected in the summer of 2016.
The board first approved this project in 2001, when Rolling Hills was an affiliate of Dynegy (NYSE: DYN). Dynegy then sold the facility in 2008 to Tenaska. It was approved as a simple-cycle plant, with initial commercial operation in 2003.