The Florida Public Service Commission on Oct. 24 approved Gulf Power’s share of the costs to install new bromine and activated carbon injection (ACI) systems on the coal-fired Daniel plant, which Gulf Power owns 50-50 with fellow Southern Co. (NYSE: SO) subsidiary Mississippi Power.
On April 1, Gulf Power filed a petition requesting that the commission approve Gulf’s inclusion of the Daniel bromine and ACI project as costs to be recovered through the Environmental Cost Recovery Clause (ECRC).
In February 2012, the U.S. Environmental Protection Agency issued the Mercury and Air Toxics Standards (MATS). The MATS rule imposes emissions limits for mercury, acid gases and particulate matter on coal and oil-fired electric utility generating units. Gulf’s Plant Daniel units 1 and 2 are subject to MATS requirements. The MATS mercury emission limit that Plant Daniel will have to meet is 1.2 lbs/TBtu (pounds/trillion Btu).
Compliance for existing sources is required by April 16, 2015, with provisions for one- and two-year extensions under limited circumstances.
Based on Daniel emissions data, as well as data from similar units, mercury emissions at the plant are estimated at 6-8 lbs/TBtu. During 2010, the company determined that, at a minimum, Plant Daniel units 1 and 2 would require the installation of SO2 scrubbers in order to comply with certain environmental regulations. The Daniel scrubbers were approved by the Florida commission for cost recovery through the ECRC in 2010. The scrubbers are scheduled for completion in 2015.
Gulf said the scrubbers will allow Daniel to achieve compliance with the particulate matter limit in MATS. However, other controls are necessary to meet the mercury limits. Gulf concluded that bromine and ACI, in conjunction with the scrubbers, rather than more capital intensive controls such as baghouses with ACI, will allow complinace with MATS. The capital cost of the bromine and ACI project is projected to be about $135m less than the baghouse installation cost.
Bromine would be added to the coal supply, which would cause mercury to be oxidized after combustion, which would then be collected in the scrubbers. The ACI system would inject powdered activated carbon into the duct work where it mixes with flue gas to absorb elemental mercury that is then captured in the precipitator. Both of these injection systems will be placed in-service with the scrubbers in the fourth quarter of 2015.
Gulf Power’s ownership interest at Daniel is associated with two coal units that have a nameplate rating of 548.25 MW each. The plant is operated by Mississippi Power. U.S. Energy Information Administration data shows that Daniel (known by its full name as Victor J. Daniel Jr.) took coal earlier this year from Peabody Energy‘s (NYSE: BTU) Foidel Creek deep mine in Colorado.