Dominion Energy Pursues Sites for Pumped Storage Facility in SW Virginia

Dominion Energy Virginia is moving forward with its plan to study the feasibility of a pumped hydroelectric storage facility in the coalfield region of Southwest Virginia by conducting studies of two potential sites. The company currently is considering two possible locations for the power station, a 4,100-acre site in Tazewell County and an abandoned mine in Wise County.

Dominion Energy filed a preliminary permit with the Federal Energy Regulatory Commission
(FERC) for the Tazewell location on Wednesday. The company has contracted with Virginia
Tech to conduct the study of the former Bullitt Mine near Appalachia, VA. “We are on parallel paths with performing studies on these two sites,” said Mark D. Mitchell,
Dominion Energy’s vice president-Generation Construction.

“The FERC application for the Tazewell site will allow us to proceed with the rigorous
environmental, geological, archeological and technical studies, while further assessing the
economics of the project. In addition, the detailed study on the mine site allows us to explore the feasibility of abandoned mine cavities for pumped hydroelectric storage. We expect to make a decision on which site to advance by mid-2018.”

The preliminary estimate for a single facility could be in the range of $2 billion and provide
millions in tax revenue to counties in the coalfield region. The project would also create
hundreds of jobs during construction and up to 50 permanent jobs when complete.

Hydroelectric storage, also known as pumped storage, works by storing water in an upper
reservoir. When electricity is needed, water is released to a lower body of water, spinning
turbines to produce electricity. When power demand is low, the water is pumped back to the upper reservoir. The station is best described as a large-scale rechargeable battery, where power is stored and then released when needed. The “on-demand” nature of pumped storage makes it an appealing resource, adding diversity to Dominion Energy’s generating fleet.

While the Tazewell and Bullitt mine sites appear to be the most promising at this time, Dominion Energy may pursue other potential sites as the process continues.

Dominion Energy owns about 2,600 acres of the Tazewell site near East River Mountain, which it purchased in 2009 when the company was pursuing another electric generation project. The Dominion Energy Virginia FERC application allows the company to perform detailed “on-the-ground” studies of the property and additional parcels needed for the project, with landowner permission. These studies will determine if the site is viable to proceed with a FERC license application later in2018.

The Tazewell site could support multiple configurations, including different-sized pumped storage facilities. The site’s flexibility enables the company to determine the best environmental, technical and economic solution.

Michael Karmis, an internationally recognized expert on coal and energy research, will lead the Virginia Tech study of the Bullitt Mine. The study will provide a conclusive report on the site’s feasibility.

The Virginia Department of Mines, Minerals and Energy conducted earlier research on the
feasibility of using abandoned mines for pumped storage and looked at numerous sites in the coalfield region. The study pinpointed the former Bullitt Mine as one of its top candidates. Closed in 1997, the abandoned site is currently flooded. Theoretically, a pumped storage facility could use the mine cavity as a lower reservoir.

Dominion Energy chose to delay filing a preliminary permit application with FERC for the Bullitt Mine site pending the results of the study by Karmis and the Virginia Tech team. If the mine is selected for a pumped storage facility, Dominion Energy would file with FERC next year.

The 2017 Virginia General Assembly passed legislation that encourages one or more pumped storage stations and includes a requirement that all or a portion of it be powered by renewable energy produced in the coalfield region.

Dominion Energy has experience in building and operating pumped storage power stations. Its Bath County Pumped Storage Station generates more than 3,000 megawatts and is the largest facility of its kind in the United States. Dominion Energy owns the station jointly with First Energy Corp.

Dominion Energy also owns and operates the Virginia City Hybrid Energy Center near St. Paul in Wise County. The 610-megawatt power station uses a combination of coal, waste coal and biomass for fuel. Since it opened in 2012, the station has used more than 2.5 million tons of waste coal to generate electricity and help clean one of the largest environmental problems in the coal region.