Watts Bar Nuclear Generating Station

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Watts Bar Nuclear Plant
Watts Bar-6.jpg
Watts Bar Nuclear Power Plant Units 1 & 2 cooling towers and containment buildings.
Watts Bar Nuclear Generating Station is located in Tennessee
Watts Bar Nuclear Generating Station
Location of Watts Bar Nuclear Plant in USA Tennessee
Country United States
Location Rhea County, near Spring City, Tennessee
Coordinates 35°36′10″N 84°47′22″W / 35.60278°N 84.78944°W / 35.60278; -84.78944Coordinates: 35°36′10″N 84°47′22″W / 35.60278°N 84.78944°W / 35.60278; -84.78944
Status Operational
Construction began 1973
Commission date Unit 1: May 27, 1996
Operator(s) Tennessee Valley Authority
Nuclear power station
Reactor type pressurized water reactor
Reactor supplier Westinghouse
Power generation
Units operational 1 x 1,121 MW
Units under const. 1 x 1,180 MW
Capacity factor 102.3%
Annual generation 10,050 GWh

The Watts Bar Nuclear Power Plant is a Tennessee Valley Authority (TVA) nuclear reactor used for electric power generation. It is located on a 1,770-acre (7.2 km²) site in Rhea County, Tennessee, near Spring City, between the cities of Chattanooga and Knoxville. Watts Bar Unit 1 is the most recent civilian reactor to come on-line in the United States. Watts Bar supplies enough electricity for about 650,000 households in the Tennessee Valley.

This plant has one Westinghouse pressurized water reactor, one of two reactor units whose construction commenced in 1973. Unit 1 was completed in 1996, and has a winter net dependable generating capacity of 1,167 megawatts.

Unit 2 construction project[edit]

TVA is currently working to finish the partially completed Unit 2. Unit 2 was about 80% complete when its construction was stopped in 1988. The official reason given for halting construction was "a reduction in the predicted growth of power demand." Unit 2 remains partly completed (several of its parts being used on other TVA units), but on August 1, 2007 the TVA Board approved completion of the unit. Construction resumed on October 15, 2007, with the reactor expected to begin operation in 2015.[1] The project was expected to cost $2.5 billion, and employ around 2,300 contractor workers. Once finished, it is estimated to produce 1,180 megawatts and create around 250 permanent jobs.[2] Unit 2 is expected to be the first new nuclear reactor to come online in the USA in nearly two decades[3] and likely the last Generation II reactor.[4]

In February 2012, TVA said the Watts Bar 2 project was running over budget and behind schedule.[5] On April 5, 2012, TVA released a revised construction schedule and cost estimate for the Unit 2 project, stating that the new target start date for Unit 2 would be by December 2015.[6] As of December 2012, the plant's cost estimate was US$4–4.5 billion.[7]

As of October, 2014 the reactor is nearing completion and open vessel testing has begun as well as testing on plant systems. Initial fuel load could come as early as spring 2015. The plant could come online as early as December 2015 or early 2016. This could be affected by delays in issuance of the unit's operating license from the NRC. Because Watts Bar Unit 2 was constructed under the NRC's original licensing regime, its current license applies only for construction. The operating license is issued after construction. NRC's new licensing scheme grants a combined construction and operation license at the beginning of construction.[8]

In May 2015 TVA cleared a major point in the licensing process when the NRC Commissioners voted to authorize the NRC staff to issue the operating license when construction is declared complete and all required inspections and regulatory requirements are met. In August, 2015 TVA declared construction substantially complete and requested that the NRC staff proceed with the final licensing review. A licensing decision by the NRC staff is expected in October, 2015. Once the license is issued, TVA will be able to proceed with loading fuel into the reactor vessel and begin final pre-startup testing.

Tritium production[edit]

The Nuclear Regulatory Commission operating license for Watts Bar was modified in September 2002 to allow TVA to irradiate tritium-producing burnable absorber rods at Watts Bar to produce tritium for the U.S. Department of Energy's (DOE's) National Nuclear Security Administration. The Watts Bar license amendment currently permits TVA to install up to 240 tritium-producing rods in Watts Bar Unit 1. Planned future license amendments would allow TVA to irradiate up to approximately 2,000 tritium-producing rods in the Watts Bar reactor.

TVA began irradiating tritium-producing rods at Watts Bar Unit 1 in the fall of 2003. TVA removed these rods from the reactor in the spring of 2005. DOE successfully shipped them to its tritium-extraction facility at Savannah River Site in South Carolina. DOE reimburses TVA for the cost of providing the irradiation services, and also pays TVA a fee for each tritium-producing rod that is irradiated.

Surrounding population[edit]

Watts Bar's cooling towers, with the Tennessee River in the foreground

The Nuclear Regulatory Commission defines two emergency planning zones around nuclear power plants: a plume exposure pathway zone with a radius of 10 miles (16 km), concerned primarily with exposure to, and inhalation of, airborne radioactive contamination, and an ingestion pathway zone of about 50 miles (80 km), concerned primarily with ingestion of food and liquid contaminated by radioactivity.[9]

The 2010 U.S. population within 10 miles (16 km) of Watts Bar was 18,452, an increase of 4.1 percent in a decade, according to an analysis of U.S. Census data for msnbc.com. The 2010 U.S. population within 50 miles (80 km) was 1,186,648, an increase of 12.8 percent since 2000. Cities within 50 miles include Oak Ridge (37 miles to city center).[10]

Seismic risk[edit]

The Nuclear Regulatory Commission's estimate of the risk each year of an earthquake intense enough to cause core damage to the reactor at Watts Bar was 1 in 27,778, according to an NRC study published in August 2010.[11][12]

See also[edit]


  1. ^ "WATTS BAR-2". PRIS. International Atomic Energy Agency. June 29, 2013. Retrieved June 29, 2013. 
  2. ^ "TVA: Watts Bar Nuclear Plant". Tennessee Valley Authority. February 10, 2008. Archived from the original on February 12, 2012. Retrieved March 14, 2012. 
  3. ^ "TVA moves toward 2012 startup of Watts Bar II". timesfreepress.com. Chattanooga Times Free Press. July 20, 2009. Retrieved March 14, 2012. 
  4. ^ Testa, Bridget (2012). "Three Generations of Nuclear Power Plants in the U.S.". Retrieved 2015-04-08. 
  5. ^ DiSavino, Scott (March 16, 2012). "TVA cuts contractors at Alabama Bellefonte nuclear site". Reuters. 
  6. ^ "TVA Releases Cost, Schedule Estimates for Watts Bar Nuclear Unit 2" (Press release). Spring City, TN, USA: Tennessee Valley Authority. April 5, 2012. 
  7. ^ "Watts Bar Unit 2 Performance On Track" (Press release). Spring City, TN, USA: Tennessee Valley Authority. December 20, 2012. Retrieved June 30, 2013. 
  8. ^ Watts Bar More than 90% complete. |url=http://www.wbir.com/story/news/local/2014/08/12/tva-watts-bar-unit-2-more-than-90-percent-complete/13982879/
  9. ^ "NRC: Backgrounder on Emergency Preparedness at Nuclear Power Plants". Fact Sheets. Nuclear Regulatory Commission. January 2009. Retrieved March 14, 2012. 
  10. ^ Dedman, Bill (April 14, 2011). "Nuclear neighbors: Population rises near US reactors". NBCNews.com. Retrieved May 1, 2011. 
  11. ^ Dedman, Bill (March 17, 2011). "What are the odds? US nuke plants ranked by quake risk". NBCNews.com. Retrieved April 19, 2011. 
  12. ^ "MSNBC Media" (PDF). 

External links[edit]