| Plant Vogtle | |
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Vogtle 1 & 2 containment buildings and cooling towers |
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| Official name | Alvin W. Vogtle Electric Generating Plant |
| Country | United States |
| Location | Burke County, Georgia, |
| Coordinates | |
| Status | Operational |
| Commission date | Unit 1: June 1, 1987 Unit 2: May 20, 1989 |
| Licence expiration | Unit 1: January 16, 2047 Unit 2: February 9, 2049 |
| Construction cost | $8.87 billion (Units 1 & 2) |
| Owner(s) | Georgia Power (45.7%) OPC (30%) MEAG (22.7%) City of Dalton (1.6%) |
| Operator(s) | Southern Nuclear |
| Architect(s) | Southern Services and Bechtel |
| Reactor information | |
| Reactors operational | 2 x 1215 MW |
| Reactors planned | 2 x 1117 MW |
| Reactor type(s) | 4-loop PWR (active), AP1000 (planned) |
| Reactor supplier(s) | Westinghouse |
| Power station information | |
| Generation units | General Electric (Units 1 & 2) |
| Power generation information | |
| Annual generation | 18,297 GW·h |
| Website Plant Vogtle — Southern Nuclear |
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The Alvin W. Vogtle Electric Generating Plant, also known as Plant Vogtle, is a 2-unit nuclear power plant located in Burke County, near Waynesboro, Georgia. It is named after the Alabama-born war hero and Alabama Power and Southern Company board chairman, Alvin Vogtle.
Each unit has a Westinghouse pressurized water reactor (PWR), with a General Electric turbine and electric generator. Units 1 and 2 were completed in 1987 and 1989, respectively. Each unit is capable of producing approximately 1,200 MW of electricity when online, for a combined capacity of 2,400 MW. Southern Nuclear lists the capacity as 1,215 MW each, for a combined output of 2,430 MW.[1] The twin cooling towers are 548 ft (167 m) tall.
During Vogtle's construction, costs skyrocketed from an estimated $660 million to $8.87 billion.[2][3] This was typical of the time due to increased regulations after the Three Mile Island accident.
In 2009, the NRC renewed the licenses for both units for an additional 20 years, to the 2040s.[4] Groundwork for two additional AP1000 reactors is underway.[5]
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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.[6]
The 2010 U.S. population within 10 miles (16 km) of Vogtle was 5,845, a decrease of 16.3 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 726,640, an increase of 8.8 percent since 2000. Cities within 50 miles include Augusta (26 miles to city center).[7]
The Nuclear Regulatory Commission's estimate of the risk each year of an earthquake intense enough to cause core damage to the reactor at Vogtle was 1 in 140,845, according to an NRC study published in August 2010.[8][9]
In 2008, both reactors were increased in power by 1.7% by an "Appendix K" uprate,[10] also called a Measurement Uncertainty Recapture uprate. "Measurement uncertainty recapture power uprates are less than 2 percent and are achieved by implementing enhanced techniques for calculating reactor power. This involves the use of state-of-the-art feedwater flow measurement devices to more precisely measure feedwater flow, which is used to calculate reactor power. More precise measurements reduce the degree of uncertainty in the power level, which is used by analysts to predict the ability of the reactor to be safely shutdown under postulated accident conditions."[11] Because the reactor power can be calculated with much greater accuracy now than with the old venturi type measurement, the plant can safely run within a tighter margin of error to their limit. The new flow meter works by comparing the time it takes ultrasonic sound pulses to travel upstream versus downstream inside the pipe, and uses that time difference to figure the flow rate of the water in the pipe.
The NRC approved Vogtle's License Amendment Request (LAR) in March 2008. "The NRC staff determined that Southern Nuclear could safely increase the reactor’s output primarily through more accurate means of measuring feedwater flow. NRC staff also reviewed Southern Nuclear’s evaluations showing the plant’s design can handle the increased power level."[12] Unit 1 was uprated during its spring 2008 defueling outage, and Unit 2 was uprated in the fall outage of the same year.
On March 20, 1990 at 9:20 a.m., a truck carrying fuel and lubricants in the plant's low voltage switchyard backed into a support column for the feeder line supplying power to the Unit 1-A reserve auxiliary transformer (RAT). This set off a complicated chain of events that was exacerbated both by planned maintenance, in which some back-up systems were off-line, and by equipment failures in some back-up systems. The resulting loss of electrical power in the plant's "vital circuits" shut down the residual heat removal (RHR) pump that was cooling Unit 1 (which was nearing the end of a refueling outage) and prevented the back-up RHR from activating. Even though Unit 1 was not operating at full-power, residual heat from the natural decay of the radioactive fuel needed to be removed to prevent a dangerous rise in core temperature.
At 9:40 a.m., the plant operators declared a site area emergency (SAE) per existing procedures which called for an SAE whenever "vital" power is lost for more than 15 minutes. At 9:56 a.m., plant operators performed a manual start of the A-train emergency diesel generator (EDG), which bypassed most of the EDG's protective trips which had prevented it from coming on-line. RHR-A was then started using power from EDG-A. With core cooling restored, the SAE was downgraded to an alert at 10:15 a.m.
The temperature of the Unit 1 core coolant increased from 90 °F to 136 °F during the 36 minutes required to re-energize the A-side bus. Ironically, throughout the event, non-vital power was continuously available to Unit 1 from off-site sources. However, the Vogtle electrical system was not designed to permit easy interconnection of the Unit 1 vital busses to non-vital power or to the Unit 2 electrical busses.[13] Since this incident, Plant Vogtle has implemented changes to the plant that allow power to be transferred from one side to the other from an off-site source.
On August 15, 2006, Southern Nuclear formally applied for an Early Site Permit (ESP) for two additional units. The ESP will determine whether the site is appropriate for additional reactors, and this process is separate from the Combined Construction and Operating License (COL) application process.[14] On March 31, 2008, Southern Nuclear announced that it had submitted an application for a COL, a process which will take at least 3 to 4 years.[15] On April 9, 2008, Georgia Power Company reached a contract agreement for two AP1000 reactors designed by Westinghouse (owned by Toshiba) and the Shaw Group (Baton Rouge, LA).[16] The contract represents the first agreement for new nuclear development in the United States since the Three Mile Island accident in 1979, and received approval from the Georgia Public Service Commission (PSC) on March 17, 2009.[17] As stated by a Georgia Power spokesperson Carol Boatright: "If the PSC approves, we are going forward with the new units."[16]
On August 26, 2009, the U.S. Nuclear Regulatory Commission (NRC) issued an Early Site Permit and a Limited Work Authorization. Limited construction at the new reactor sites has begun, with Unit 3 expected to be operational in 2016, followed by Unit 4 in 2017, pending final issuance of the Combined Construction and Operating License by the NRC.[18][19]
The Vogtle Electric Generating Plant consists of two operational reactors; two additional units are planned.
| Reactor unit[20] | Reactor type | Capacity | Construction started | Electricity grid connection | Commercial operation | Shutdown | |
|---|---|---|---|---|---|---|---|
| Net | Gross | ||||||
| Vogtle-1 | Westinghouse 4-loop | 1150 MW | 1203 MW | 01.08.1976 | 27.03.1987 | 01.06.1987 | |
| Vogtle-2 | Westinghouse 4-loop | 1152 MW | 1202 MW | 01.08.1976 | 10.04.1989 | 20.05.1989 | |
| Vogtle-3 (planned)[21] | AP1000 | 1117 MW | MW | ||||
| Vogtle-4 (planned)[22] | AP1000 | 1117 MW | MW | ||||
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