The Tennessee Valley Authority has removed from service, mothballed and/or idled an additional 14 coal-fired units with a summer net capability of 2,170 MW, the federal utility reported in its Aug. 5 Form 10-Q quarterly report.
The decision to idle or retire coal-fired units from the Tennessee Valley Authority’s generation fleet is being influenced by several factors including two environmental agreements reached in April 2011, the cost of adding emission control equipment and other environmental improvements, fuel prices, condition of plants, and demand for energy. Under the environmental agreements, TVA committed, among other things, to retire, on a phased schedule, 18 coal-fired units.
“As of June 30, 2014, per the requirements of the Environmental Agreements, TVA has retired four coal-fired units with a summer net capability of 574 megawatts (‘MW’),” the Form 10-Q said. “TVA continues to assess its power generating facilities, including its aging coal-fired fleet. Notwithstanding the Environmental Agreements, TVA has removed from service, mothballed and/or idled an additional 14 coal-fired units with a summer net capability of 2,170 MW. As of June 30, 2014, TVA has notified the respective states of the retirement of seven of these 14 units — Widows Creek Fossil Plant Units 1, 2, 4 and 6, John Sevier Fossil Plant Units 3 and 4, and Shawnee Fossil Plant Unit 10 — from the Environmental Protection Agency’s (‘EPA’s’) emission allowance and reporting system, rendering these units inoperable.”
At a November 2013 meeting, the TVA Board approved the completion of a natural gas-fired facility at the Paradise Fossil Plant in western Kentucky and the subsequent retirement of the coal-fired Units 1 and 2 at the plant. Paradise Unit 3, a coal-fired unit, would continue to be operated. A lawsuit has been filed by the Kentucky Coal Association in the U.S. District Court for the Western District of Kentucky seeking to at least temporarily block TVA from taking any further action towards retiring and replacing Paradise Units 1 and 2. Any injunction or court order that delays TVA’s plans could increase the project’s costs, TVA noted.
In July 2014, the Kentucky Coal Association and a group of individuals and businesses filed this lawsuit against TVA. They allege, among other things, that TVA violated the National Environmental Policy Act (NEPA) in various ways, including not preparing an Environmental Impact Statement (EIS) for the retirement of two of the three units at Paradise and the construction of a natural gas power plant, and violated the TVA Act by not choosing the least-cost alternative. The plaintiffs seek, among other things, an injunction barring TVA from taking any action with regard to retiring and replacing the two Paradise units until TVA complies with NEPA.
The TVA Board has also approved the retirement of the coal-fired Colbert Units 1-5 no later than June 30, 2016, as well as the retirement of Widows Creek Unit 8 in the future. TVA has evaluated options for idling, controlling, or replacing its Allen Fossil Plant and plans to present a recommendation to replace the coal-fired Allen plant with a natural gas-fired facility to the TVA Board for approval in August 2014.
Utility makes progress on expensive CCR fixes
Another coal-related area of activity for TVA has to do with coal combustion residual (CCR) facilities. As a result of a December 2008 ash spill at the Kingston plant in Tennessee, TVA retained an independent third-party engineering firm to perform a multi-phased evaluation of the overall stability and safety of all existing embankments associated with TVA’s wet CCR facilities.
The study showed that none of TVA’s other coal-fired plants presented risks similar to the conditions that existed at Kingston at the time of the ash spill, and that the ongoing remediation work being done at the plants should bring all of them within industry standards in terms of stability upon completion. Implementation of recommended actions is ongoing, including risk mitigation steps such as performance monitoring, designing and completing repairs, developing planning documents, obtaining permits, and generally implementing the lessons learned from the Kingston ash spill at TVA’s other CCR facilities.
TVA said it is planning to convert its wet ash and gypsum facilities to dry storage collection facilities. The expected cost of the CCR work is between $1.5bn and $2bn, and the work is expected to be completed by December 2022. As of June 30, $575m of costs had been incurred since the start of the work.
TVA is also studying the adequacy of CCR storage capacity at its coal-fired plants that currently have dry storage collection facilities. If it is decided that the remaining capacity is not adequate, additional storage facilities will need to be permitted and built, or off-site disposal will need to be arranged.