Raccoon Mountain Pumped-Storage Plant

Raccoon Mountain Pumped-Storage Plant
Tailrace (TN River) of RMPS (TVA photo)
Location of Raccoon Mountain Pumped-Storage Plant in Tennessee
Country	United States
Location	Marion County, Tennessee
Coordinates	35°2′54″N 85°23′48″W
Purpose	Power
Status	Operational
Construction began	July 1970 (1970-07)[1]
Opening date	1978 (1978)
Construction cost	$310 million (1978)[2][3]
Owner(s)	Tennessee Valley Authority
Operator(s)	Tennessee Valley Authority
Upper dam and spillways
Type of dam	Embankment dam
Height (foundation)	230 feet (70 m)[4]
Length	8,500 feet (2,600 m)[4]
Dam volume	10,000,000 cubic yards (7,600,000 m^3)[1]
Upper reservoir
Total capacity	107,000,000,000 US gallons (4.1×10^11 L; 8.9×10^10 imp gal)[4]
Surface area	528 acres (214 ha)[4]
Maximum water depth	222 feet (68 m)
Normal elevation	1,672 feet (510 m)
Lower dam and spillways
Type of dam	Gravity dam
Impounds	Tennessee River[5]
Height (foundation)	81 feet (25 m)[5]
Length	3,767 feet (1,148 m)[5]
Elevation at crest	635.0 feet (193.5 m)
Spillways	10
Spillway type	Radial gate
Lower reservoir
Creates	Nickajack Lake[5]
Total capacity	252,297 acre-feet (311,204,000 m^3)
Active capacity	32,132 acre-feet (39,634,000 m^3)
Catchment area	21,870 square miles (56,600 km^2)
Surface area	10,370 acres (4,200 ha)[5]
Maximum water depth	145 feet (44 m)
Normal elevation	633.5 feet (193.1 m)
Power Station
Operator(s)	Tennessee Valley Authority
Commission date	1978 (1978)
Type	Pumped-storage
Hydraulic head	1,040 feet (320 m)
Pump-generators	4 × 413 MW
Installed capacity	1652 MW
Capacity factor	20%[6]
Storage capacity	22 hours
2017 generation	-686 GW·h
Website Raccoon Mountain

Raccoon Mountain Pumped-Storage Plant is a pumped-storage hydroelectric underground power station in Marion County, just west of Chattanooga in the U.S. state of Tennessee. Owned and operated by the Tennessee Valley Authority (TVA), the plant can generate a maximum of 1,652 megawatts of electricity. The reservoir at the top of the mountain covers 528 acres (214 ha), with a dam that is 230 feet (70 m) high and 5,800 feet (1,800 m) long, the largest rock-fill dam ever built by TVA. The plant serves as an important element for peak power generation and grid balancing in the TVA system.

Construction was started in 1970 and was completed in 1978.^[7] The plant was idled in March 2012 due to cracks in the generators' rotors. The plant came entirely back on line in April 2014.^[8]

Diagram of the facility

The underground powerhouse

Operation

During periods of high electric demand, water flows from reservoir into a tunnel drilled through the center of the mountain, driving electric generators in the underground powerhouse.^[7] During periods of low demand and excess generation, the generators run in reverse and pump water from Nickajack Lake back up to the top of the mountain, where it is stored until needed later. This process repeats continuously, serving as peak power generation. The plant has a maximum power output of 1,652 megawatts (2,215,000 hp) and can generate power for up to 22 hours.^[9][10]

Recreation

The TVA operates a visitor center, open year-round, that offers exhibits on the history of the generating facility as well as the TVA’s operations. The center also offers views of the Tennessee River gorge and surrounding mountains.^[7]

Raccoon Mountain is used for hiking, walking, running, and road and mountain biking. It hosts a marathon, half marathon, double half marathon, relay, 5K and 10K race each year.^[11]

References

1. "TVA - The Mountaintop Marvel". www.tva.gov. Tennessee Valley Authority. Retrieved 3 April 2018.
2. "Repairs for Raccoon Mountain pumped-storage hydro facility pass $50 million". www.hydroworld.com. 30 November 2012. Retrieved 3 April 2018.
3. Poindexter, Gregory B. (26 May 2016). "TVA to begin geophysical testing at 1,652-MW Raccoon Mountain pumped-storage project". www.hydroworld.com. Retrieved 3 April 2018.
4. "TVA - Raccoon Mountain". www.tva.gov. Tennessee Valley Authority. Retrieved 3 April 2018.
5. "TVA - The Great Replacement". www.tva.com. Tennessee Valley Authority. Retrieved 3 April 2018.
6. "Integrated Resource Plan: 2015 Draft Supplemental Environmental Impact Statement" (PDF). Tennessee Valley Authority. March 2015. Retrieved 3 April 2018.
7. TVA: Raccoon Mountain Pumped-Storage Plant
8. Sohn, Pam (August 10, 2012). "TVA's pumped storage facility on Raccoon Mountain idle". Chattanooga Times Free Press. Archived from the original on August 12, 2012. Retrieved August 26, 2012.
9. Adkins, F.E., 1987, TVA Report "Raccoon Mountain pumped storage plant; Ten years operating experience," IEEE Transactions on Energy Conversion, Volume EC-2, Issue 3 (September 1987), pages 361 - 368. CODEN:ITCNE
10. The Mountaintop Marvel, TVA Heritage website, accessed September 8, 2010
11. "Raccoon Mountain Marathon, Half Marathon, and Relay | Run Chattanooga". runchattanooga.org. Archived from the original on 2014-11-14.

External links

• Media related to Raccoon Mountain Pumped-Storage Plant at Wikimedia Commons