SWEPCO says controls to save Flint Creek would bolster the grid

Southwestern Electric Power filed promised new testimony Jan. 11 at the Arkansas Public Service Commission in support of new emissions controls at the coal-fired Flint Creek power plant, including evidence from the Southwest Power Pool that a shutdown of the plant would cause grid instability in that area.

Lanny Nickell, employed by Southwest Power Pool (SPP) as Vice President, Engineering, said that SPP staff performed voltage stability analysis for the Northwest Arkansas area or “load pocket” that examined both thermal and voltage performance during power transfer. The objective of the analysis was to determine whether NERC reliability standards and SPP Criteria can be met in the Northwest Arkansas and surrounding areas if Flint Creek were retired. The analysis generally assessed the impacts of replacing Flint Creek generation with existing energy sources that would be imported into the load pocket to support the energy demand of the load pocket.

SPP used a model that had been developed and approved for utilization in its Integrated Transmission Plan (ITP) Near-Term planning process. The model utilized for this analysis reflects 2014 summer peak conditions and expected transmission upgrades that will be in service by 2014 summer peak.

“The results of this analysis indicate that once Flint Creek is removed from service, severe thermal  overloads and voltage decreases occur due to transfers into the load area,” Nickell wrote. “These thermal overloads and voltage reductions increase the threat of cascading transmission outages within the area that would result in voltage collapse and customer power outages.”

Venita McCellon-Allen, employed by American Electric Power Service Corp. (AEPSC) as Southwestern Electric Power’s President and Chief Operating Officer, said in separate Jan. 11 testimony that the installation of environmental controls at the Flint Creek plant is in the best interest of the customers of SWEPCO and Arkansas Electric Cooperative (AECC), which co-owns the plant.

“The Flint Creek Plant provides 528 MW of baseload capacity in the 13 Northwest Arkansas area – and it provides the only baseload capacity in the area,” McClellon-Allen wrote. “As extensively discussed during the previous hearing, Northwest Arkansas is a load pocket in which the demand for electric capacity and energy significantly exceeds the output from existing generation in the area. If Flint Creek is retired, SWEPCO and AECC must replace the generating capacity each currently derives from the plant. In addition, as discussed in more detail hereafter, the ability to obtain transmission service through SPP becomes critical to the decision as to the most prudent replacement capacity resource SWEPCO and AECC choose to pursue. Indeed, additional reliability risk will be introduced to customers in Northwest Arkansas regardless of the replacement scenarios the parties choose.”

The Arkansas commission has agreed to a request from SWEPCO and reopened the record in a long-running case involving a proposed new SO2 scrubber and other emissions controls for the coal-fired Flint Creek power plant. On Oct. 9, 2012, the Arkansas commission concluded the evidentiary hearing in this proceeding and held the record open for the submission of post-hearing closing arguments. They were filed on Nov. 16, 2012.

On Dec. 14, 2012, SWEPCO, AECC and the Arkansas Attorney General (AG) filed a joint motion to reopen record “for the purpose of receiving additional evidence which the parties believe will more filly develop the record and assist the Commission in reaching a decision in this case….”

The companies said their senior management have had extensive discussions about the alternatives to providing the generation output of the Flint Creek plant if the commission denies the pending petition for a declaratory order finding that installation of environmental controls at the plant is in the public interest. PSC staff did not object to the petition to reopen, but the Sierra Club did, arguing that there had been ample evidence offered in this case. The Sierra Club, by the way, opposes the emissions projects and has claimed that other, cleaner options should be pursued.

SWEPCO and AECC said they have held discussions with business leaders in Northwest Arkansas and with SPP officials. SWEPCO and AECC anticipate that Northwest Arkansas business leaders will provide direct testimony in support of SWEPCO and AECC. In addition, SWEPCO and AECC have requested that a representative of SPP file direct testimony offering its independent view of the potential impact on the integrity of the SPP transmission system if Flint Creek is retired prior to replacement generating capacity or additional transmission lines in Northwest Arkansas being operational.

The commission in a Jan. 2 order said it finds that the public interest will be served by reopening the record of this proceeding. Additional direct testimony by SWEPCO and AECC has to be filed by Jan. 11. Reply testimony by staff, the AG and the Sierra Club now has to be filed by noon on Feb. 22. A public evidentiary hearing is set for March 5.

SWEPCO, a unit of American Electric Power (NYSE: AEP), filed the original application with the PSC in February 2012. It asked the commission for a declaratory order approving installation of $408.7m worth of new emissions controls on Flint Creek. The planned controls include: dry flue gas desulfurization (DFGD) equipment for SO2 control; activated carbon injection (ACI) for mercury; and Low NOx burners and over-fired air facilities for NOx control. The DFGD system selected by the project engineers will also include a pulse jet fabric filter, commonly called a baghouse.

Flint Creek is a single-unit, pulverized coal-fired plant with a net capacity of 528 MW and was placed in service in 1978. SWEPCO’s ownership portion of this unit is 264 MW net, and it is responsible for operating and maintaining the plant.

About Barry Cassell 20414 Articles
Barry Cassell is Chief Analyst for GenerationHub covering coal and emission controls issues, projects and policy. He has covered the coal and power generation industry for more than 24 years, beginning in November 2011 at GenerationHub and prior to that as editor of SNL Energy’s Coal Report. He was formerly with Coal Outlook for 15 years as the publication’s editor and contributing writer, and prior to that he was editor of Coal & Synfuels Technology and associate editor of The Energy Report. He has a bachelor’s degree from Central Michigan University.