What you see coming out of the cooling tower is clean water vapor, not steam. The water vapor that is produced is not part of the radioactive process.

Callaway became operational in December 1984. The NRC granted a 40-year operating license, which is the customary license for nuclear power plants. In 2015, the NRC granted Callaway a 20 year license extension, allowing operation through 2044.

Callaway produces enough electricity to power over 800,000 average households each year. Electricity from nuclear power accounts for 9.7% of all electricity sources in Missouri - compared to 73% in Vermont and about 50% in New Jersey, South Carolina, Illinois and Connecticut. Overall, nuclear energy provides about 20% of the electricity in the U.S.

Every nuclear power plant in the U.S. currently stores its own spent fuel. Callaway safely stores its used fuel on site in the spent fuel pool, which is about the size of a tennis court and in an underground dry cask storage facility. The U.S. Government is exploring a national repository for used fuel underneath Yucca Mountain in Nevada.

Callaway Energy Center is the only nuclear energy center among the companies' 15 generating facilities. Callaway is the second largest power producer on the Ameren Missouri system producing 24% of the company's electricity.

Callaway employs nearly 1,000 people, including contractors, with an annual payroll of approximately $100 million. When the energy center is refueling, hundreds of additional contractors are on site adding nearly $20 million to the payroll. Most of Ameren Missouri's full-time employees working at the Callaway Energy Center live in Callaway, Cole and Boone counties. However, more than 100 employees reside in 24 other Missouri counties.

2019 - Celebrated 35 years of safe and reliable operation

2018/2019 - Callaway operated continuously for 467 days, achieving what is known in the industry as a “breaker-to-breaker” run — which means it operated from one refueling to the next without ever being out of service. This marked Callaway’s fifth breaker-to-breaker run since it began operating in 1984, the first coming in 2008 (520 days), second in 2012 (489 days), third in 2013 (500 days), and fourth in 2017 (514 days).

2015 - License extended to 2044 & first dry fuel storage campaign

2014 - Reactor vessel head replacement

2011 - Callaway operated continuously for 489 days, achieving what is known in the industry as a "breaker-to-breaker" run - which means it operated from one refueling to the next without ever being out of service. This marked Callaway's second breaker-to-breaker run since it began operating in 1984 - the first coming in 2008 (520 days). Callaway is one of only 26 of the nation's 104 nuclear plants to achieve a breaker-to-breaker run. 

Dec. 19, 2009 - Callaway celebrates 25 years of safe and reliable operation. 2009 also marks the most electricity generated by the station in a calendar year. 

2008/2009 - Callaway becomes an industry leader by replacing the carbon steel piping in the Essential Service Water (ESW) system with more durable plastic high-density polyethylene (HDPE) piping. The project marks the first time for HDPE use in an American Society of Mechanical Engineers (ASME) safety-related system in the United States. Callaway also received a Top Industry Practices (TIP) award for the project. 

Fall 2008 - Callaway completes first ever sub 30-day refueling outage by wrapping up Refuel 16 in 27.9 days. The facility must refuel every 18 months and continues to execute outages with greater efficiency. 

Oct. 20, 2008 - Callaway completes first ever "breaker to breaker" run. The facility remained online for all 520 days of cycle 16. Only a handful of the nation's 104 nuclear plants have accomplished this milestone. 

2006 - Callaway receives the prestigious Edison Electric Institute Safety Achievement Award for outstanding worker safety. 
  

Summer/Fall 2005 - Callaway replaces all four steam generators. Each steam generator is about 70 feet long and 17 feet in diameter at its widest point and weighs 360 tons.  

May 2, 1996 - Callaway's lifetime power generation reaches 100 billion kilowatthours. At that time, only 28 nuclear energy centers in the U.S. had achieved that mark, and Callaway reached it more quickly than any other energy center. 

Summer 1993 - Callaway operates at full capacity throughout the "Flood of '93," helping to ensure an adequate power supply to Ameren customers, while high water interrupts fuel delivery to the company's coal-fired energy centers.  

Dec. 31, 1989 - Callaway completes its fifth year of service, having generated more electricity during that period than any other nuclear plant in the United States. Callaway is also the only U.S. nuclear plant to rank among the top ten nuclear plants in the world in total power production.  

Apr. 18, 1986 - Callaway completes its first refueling outage (refuelings occur every 18 months).

Dec.19, 1984 - Required testing completed - Callaway declared fully operational.  

Oct. 18, 1984 - “Full power” operating license issued by the Nuclear Regulatory Commission (NRC).

Oct. 2, 1984 - Callaway’s first nuclear chain reaction takes place.  

June 13, 1984 - Initial fuel load.  

June 11, 1984 - “Low power” operating license issued by the NRC.  

Nov. 16, 1982 - Initial fuel delivery.  

Oct. 19, 1979 - Application made to the NRC for Callaway's operating permit.  

Apr. 16, 1976 - Construction permit granted by the NRC.  

Aug. 14, 1975 - Limited Work Authorization granted by the U.S. Nuclear Regulatory Commission (NRC).

Apr. 1, 1975 - Certificate of Convenience and Need granted by the Missouri Public Service Commission.  

July 16, 1973 - Project announced and site selected.