Duke Energy Florida applied on Aug. 1 at the Florida Department of Environmental Protection for an air permit on the 1,640-MW Citrus County combined-cycle project, to be built next to the existing Crystal River power plant.
The utility, a unit of Duke Energy (NYSE: DUK), is also currently seeking a Florida Public Service Commission approval for this project, which would more than replace the coal-fired Units 1 and 2 at Crystal River (965 MW in total), which are due to be retired. The permit for Citrus County is technically considered an amendment to the Crystal River air permit. The project is called the “Citrus Combined Cycle” (CCC) in the application.
The application shows that the project will include four combustion turbine generators (CTGs), each being a Mitsubishi 501GAC model. Each would produce a nominal 270 MW. The plant would be arranged in two power blocks, with each block consisting of two CTGs, two heat recovery steam generators (HRSGs) equipped with duct burners, and one steam turbine arranged in a two-on-one configuration.
An inlet chiller system for the plant is being considered, and is covered by the application, but the decision is not final to install it. One auxiliary steam boiler rated at 216.2 MMBtu/hr and one diesel-fired emergency firewater pump rated at 575 horsepower (hp) will service both power blocks.
“Construction of the CCC Project is anticipated to start in early 2016, with commercial operation planned for May 2018 for the first power block and December 2018 for second power block,” said the application.
Dry low-NOx combustion and selective catalytic reduction (SCR) will be used to control NOx emissions from the CTG/HRSG. Good combustion practices will be used to control CO and VOC emissions.
The project will fire natural gas exclusively in the CTGs and HRSG duct burners, as well as the auxiliary boiler and the fuel gas dew point heaters. The project will fire ultra-low-sulfur diesel (ULSD) fuel oil exclusively in the new emergency generator diesel engine and the new emergency firewater pump engine.