Although nuclear plants are theoretically engineered to operate safely for 40 years, almost two dozen reactors were shut down long before their initial license/design life expired. Among plants built before 1973, fully HALF did not make it to 40 years, or much beyond that, before closing down.
Some nuclear plants were shut down for economic reasons, but most plants simply wore out, broke down, or never functioned properly in the first place. This record of failure can be viewed in the closure report below. You can also view this chart in its original printable PDF form.
Ages of US Nuclear Power Plants* at Closure
PLANT
SHUTDOWN DATE
AGE
REASON / NOTES
Connecticut Yankee
December 1996
29 yrs
Steam tube damage, ECCS undersized
Millstone I (CT)
July 1998
28 yrs
Improper operation, Cost of safety improvements
Maine Yankee
August 1997
25 yrs
Steam generator tube damage, Electrical power cable separation
Yankee Rowe (MA)
October 1991
28 yrs
Reactor vessel embrittlement, Steam generator tube damage
Three Mile Island II (PA)
March 1979
4 months
Partial meltdown!
Indian Point I (NY)
October 1974
12 yrs
Lack of an Emergency Cooling System
Shippingport (PA)
October 1982
35 yrs
1st commercial plant in US
Peach Bottom I (PA)
November 1974
7 yrs
Helium cooled graphite core
Dresden I (IL)
October 1978
18 yrs.
1st full scale private funded plant
Zion I (IL)
February 1997
22 yrs.
Steam generator tube cracking, poor operation
Zion II (IL)
November 1996
22 yrs.
Steam generator tube cracking
Big Rock Point (MI)
August 1997
35 yrs.
Economics
Fermi I
September 1972
2 yrs.
Partial meltdown, 1966! Restarted (?) 1970-72
La Crosse (WI)
April 1987
17 yrs.
Economics
Fort St. Vrain (CO)
August 1989
10 yrs.
Helium cooled graphite core, Control rod failure, never dependable
Trojan I (OR)
November 1992
16 yrs.
Steam generator cracking, economics
San Onofre I (CA)
November 1992
25 yrs.
Cost of seismic retrofit, Steam generator tube cracking
San Onofre II/III (CA)
January 2012
30/29 yrs.
Steam generator tube cracking
Humbold Bay (CA)
July 1976
17 yrs.
2nd oldest commercial plant
Rancho Seco (CA)
June 1989
15 yrs.
Poor operating history (39% capacity)
Only nuclear plant closed by referendum
Kewaunee (WI)
May 2013
39 yrs.
Economics
Crystal River 3 (FL)
September 2009
33 yrs.
Steam generator, containment cracking
* US commercial plants of significant size that shut down prior to their initial license expiration (40 years)
Oldest Operating U.S. Nuclear Plants
PLANT
START DATE
AGE
ISSUES
Oyster Creek
December 1969
47 yrs.
Oldest running in US (closure in 2019)
Thermal pollution to bay
GE mark I (Fukushima type)
Nine Mile Pt. I
December 1969
47 yrs.
Internal cracking (worst nationally)
Cooling system malfunctions
R.E. Ginna (NY)
June 1970
46 yrs.
Radiation release in 1982
Steam generators replaced
Dresden II (IL)
June 1970
46 yrs.
Cooling system failure, 1989
Point Beach I (WI)
1970
46 yrs.
2nd oldest in total hours run
Monticello (MN)
1971
45 yrs.
GE mark I (Fukushima type)
“Safety culture” issues
U.S. Commercial Plants Operating by/before 1973 = 38. Number of these still operating today (at 43+ yrs) = 19 (50%)
Oldest Reactors Around the World
PLANT
START DATE
AGE
ISSUES
Obninsk (Russia)
1954
48 at shutdown
5MW
Calder Hall (UK)
1953
47 at shutdown
military/commercial
Chapelcross (UK)
1959
45 at shutdown
military/commercial
Oldbury (UK)
1967
45 at shutdown
Shut down on 2/29/12
Beznau 1 (Swiss)
1969
47
Slated for shutdown
Tsuruga – 1 (Japan)
1970
41 at shutdown
Radiation leaks, Shut down on 3/2011
Permanent shutdown 3/2015
Sources:
US Energy Info Administration: http://www.eia.gov/cneaf/nuclear/page/nuc_reactors/shutdown.html
Wikipedia: http://en.wikipedia.org/wiki/List_of_nuclear_reactors – Power_station_reactors_19
Nuke plants list: http://www.animatedsoftware.com/environm/no_nukes/nukelist1.htm
Compiled by Doug Bogen
Seacoast Anti-Pollution League
PO Box 1136, Portsmouth, NH 03802
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