The Florida Department of Environmental Protection on Dec. 16 issued a draft approval for a minor source air construction (AC) permit that in part covers Duke Energy Florida‘s plans to retire the coal-fired Units 1 and 2 at the Crystal River power plant.
Also, said a DEP permit document: “This permitting action is intended to confirm attainment of the 1‐hour SO2 National Ambient Air Quality Standard (NAAQS) for future years based on modeled emissions of the Crystal River Plant’s potential emission rates in response to the U.S. Environmental Protection Agency’s (U.S. EPA’s) Data Requirements Rule (DRR).”
This application, filed by the utility on Nov. 18, lowers the SO2 emission limit for the surviving, coal-fired Crystal River Units 4 and 5 from 0.27 pounds per million British thermal units (lb/MMBtu) of heat input based on a 30‐day rolling average to 0.25 lb/MMBtu based on a 30‐day rolling average. Compliance with the revised SO2 emission limit is to occur on or before Dec. 31, 2017.
“DEF is submitting this construction permit application to address the upcoming retirement of Units 1 and 2 and for incorporation of a new SO2 emission limit for Units 4 and 5,” said this Duke Energy (NYSE: DUK) subsidiary in the Nov. 18 application. “This permitting action is intended to allow DEP to confirm attainment for the 1‐hour SO2 National Ambient Air Quality Standard (NAAQS) for future years based on modeled emissions of the Crystal River Plant’s potential emission rates in response to the U.S. Environmental Protection Agency (EPA) Data Requirements Rule (DRR).”
The plant operates primarily on coal but is permitted to use No. 2 fuel oil or natural gas for startup. The nuclear Unit 3 was retired earlier this decade.
Units 4 and 5 each consists of a pulverized coal, dry bottom, wall‐fired boiler rated at 760 MW. Units 4 and 5 share a common 550-foot-tall chimney with separate internal stack liners with continuous emissions monitoring systems (CEMS) on each stack liner. Unit 4 began commercial operation in 1982 and Unit 5 began commercial operation in 1984. Air pollution control equipment on Units 4 and 5, each, include: low‐NOX burners; SCR systems; AMM systems; an ESP; and FGD systems.
Currently, under a Title V Operation Permit, Units 4 and 5 are limited to SO2 emissions of 0.27 lb/MMBtu of heat input based on a 30‐day rolling average for all periods of operation including startup, shutdown, and malfunction, as determined by CEMS data. Based on modeling as conducted by the DEP in response to EPA’s DRR, DEP is requesting that DEF voluntarily accept a modified SO2 emission limit of 0.25 lb/MMBtu of heat input based on a 30‐day rolling average. DEF said it will demonstrate compliance with the revised emission limit by the end of 2017. This revised SO2 emissions limit reflects a decrease in allowable emissions only, by reducing compliance margin. DEF will not undergo a physical change or change in the method of operation as a result of the revised emissions limit requested in this application.
Modeled attainment can be demonstrated for future years based on the updated potential SO2 emissions factor of 0.25 lb/MMBtu for Units 4 and 5 and the inclusion of four combined cycle gas turbines to be operating in 2019 (part of the adjacent Citrus Combined Cycle Project (CCCP)). Crystal River Units 1 and 2 will be retired in conjunction with the operation of the CCCP.
Unit 1 is a pulverized coal, dry bottom, tangentially‐fired boiler rated at 440.5 MW. Unit 2 is a pulverized coal, dry bottom, tangentially‐fired boiler rated at 523.8 MW. Emissions from Units 1 and 2 are each controlled with a high efficiency electrostatic precipitator (ESP). In addition, the use of hydrated lime injection and activated carbon injection may be used, as necessary. Unit 1 began commercial operation in 1966, while Unit 2 began operating in 1969.
Under an existing permit, Units 1 and 2 are committed to cease operation as coal‐fired units by Dec. 31, 2020. Furthermore, as part of the CCCP project’s air permit, Administrative Requirement 8 indicates that DEF shall not commence operation of both combined cycle blocks until both Units 1 and 2 have permanently shut down. DEF is including language in this permit application proposing a voluntary Dec. 31, 2018, shutdown date for Units 1 and 2, or prior if the CCCP commences operation by then.