Winter Storm Elliot forced rolling blackouts across Tennessee in late December 2022. Sustained single-digit temperatures crippled some of the Tennessee Valley Authority (TVA)’s generating equipment as demand spiked. For the first time ever, the TVA instructed local power companies to curtail electricity demand, first by 5% on December ’23 and then by 10% for over 5 hours on Christmas Eve. The estimated financial impact totaled around $170 million.
The storm is just one example of the growing impact that extreme weather has on electricity systems across the nation. Utilities from Vermont to Florida, Texas, California, and beyond have all dealt with substantial and costly damage from climate-change related events over the past few years. A new paper from Vanderbilt Law School’s Caroline Cox and Jay Eischen explores how utilities – and the TVA in particular – prepare the electric grid for climate change.
“Winter Storm Elliott was a potent illustration of the need for electric-system resilience in the TVA region,” they write in Climate Resilience Planning and the TVA. A resilient system, as they describe it, can withstand and recover from extreme conditions. During Winter Storm Elliot, Chattanooga was able to fare slightly better than other cities in TVA territory due to its investment in resilience measures like battery storage.
The authors provide an overview of resilience and its place in the electric grid before delving into the regulatory environment, best practices, and case studies from other electric utilities. It then shifts focus to the TVA, benchmarking its resilience planning processes against those best practices.
The TVA’s Resilience Planning Has Substantial Limitations
By reviewing the TVA’s recent Climate Change Adaptation and Resiliency Plans and a 2022 report from the Government Accountability Office, the authors found significant shortcomings in the TVA’s efforts around resiliency planning. The TVA has not developed comprehensive vulnerability assessments, which would, among other things, involve a cataloging of assets and threats faced by each. Local Power Companies (LPCs) under the purview of the TVA have hard caps on their ability to improve resilience through distributed generation. TVA’s plans do not allow for adequate evaluation of alternative measures (such as battery storage or undergrounding transmission lines) that could help TVA identify effect solutions.
“The shortcomings of TVA’s resilience planning processes may be a result, in part, of the company’s governance,” the authors explain. TVA’s status as a federal agency, with jurisdictional limits Imposed through the Federal Power Act, leaves few mechanisms for imposing a climate resilience framework on the authority. Executive Orders, which are easily rescindable and generally do not provide a cause of action for private citizens, have been the primary drivers of resilience planning for TVA. There are economic realities to contend with as well. Distributed generation resources may improve resilience while reducing the amount of power purchased from TVA, threatening revenues for the Authority, which does not receive taxpayer funding.
Recommendations
Structural Issues aside, “utilities that fail to plan for resilience adequately and transparently not only risk imposing unnecessary outages on their customers but may also face potential legal liability,” the authors note. The paper ends with several recommendations for the TVA:
- Complete a comprehensive vulnerability assessment, starting with a catalogue of assets and threats for each, and then act on it.
- Facilitate LPC participation. The TVA should consider opening its planning process up to least-cost resource proposals from LPCs and maybe others, Including customers and project developers.
- Integrate transmission planning and resilience concerns into the IRP process, providing more transparency in its transmission planning process.
- Encourage LPCs to conduct their own resilience planning, potentially integrating these plans into TVA’s broader resilience planning framework.
- Encourage LPCs to develop flexible generation resources. This could include eliminating the 5% cap on distributed generation, working around the cap, or granting exceptions on a case-by-case basis.
“As climate change continues, climate scientists project more extreme weather events, not less,” the authors write. “And with these increasing storm impacts come an increasing need for a resilient electric grid.”
Climate Resilience Planning and the TVA is a publication of the Energy, Environment & Land Use (EELU) Program at Vanderbilt Law School. Caroline Cox is the Program Director of the EELU Program. Jay Eischen ’25 is a student at Vanderbilt Law School and was a fall 2023 EELU Research Fellow.
