It’s been 25 years since the first of two units at Comanche Peak Nuclear Power Plant began supplying power to the state’s electric grid. That day – Aug. 13, 1990 – was the culmination of a long journey through construction and commissioning, and the beginning of a growing history of memories and milestones.
Now, more than 422 million megawatt-hours later as we mark 25 years of reliable operations, Comanche Peak has become much more than a source of dependable electricity. From colossal construction to dinosaur discoveries, massive megawatts to powerful pellets, here are just 25 things you might not know about Comanche Peak:
- On May 14, 1975, construction on the Unit 1 reactor containment building was stopped when about 20 Acrocanthosaurus dinosaur tracks were discovered. Additional tracks were found at Squaw Creek Reservoir. You can see one of them, along with other tracks and fossils found around the site, on display at the Comanche Peak Visitors Center.
The plant’s name was inspired by a nearby landmark mesa, Comanche Peak, whose summit reaches 1,230 feet above sea level.
- Comanche Peak Nuclear Power Plant sits on 10,000 acres between Glen Rose and Granbury, about 45 miles southwest of Fort Worth.
- During the height of construction in the mid-1980s, more than 10,000 employees worked at the plant. Today, about 1,300 people are needed to support units 1 and 2.
- More than 200 of the employees who were on hand for the first day of operation on Aug. 13, 1990, are still employed at Comanche Peak today.
- After the last bucket of concrete was poured in October 1979, crews placed an evergreen tree – a European tradition considered a symbol of good luck in the construction industry – atop the dome.
- Some 450,000 cubic yards of concrete was used in the construction – enough to pave a two-lane highway from the plant to Oklahoma City.
- At 25 and 22 years old, Comanche Peak’s two reactors are the youngest of the
four units in Texas. In the U.S., only Watts Bar 1 in Tennessee is younger.
- The two reactors have a capacity to generate 2,300 megawatts of energy. That’s enough to power 1.15 million homes in normal conditions and 460,000 homes in periods of peak demand.
- A single uranium fuel pellet the size of a fingertip contains as much energy as 17,000 cubic feet of natural gas, 1,780 pounds of coal or 157 gallons of gasoline – enough to fuel a car trip from Dallas to New York City and back.
- Comanche Peak holds the world-record of 55 days for the shortest duration steam generator and reactor vessel head replacements, which occurred during the Unit 1 Spring 2007 outage.
- The 3,275 acres of water in Squaw Creek Park Reservoir average 46 feet deep – with some areas reaching 125 feet deep – and serve as the cooling source for Comanche Peak’s two units.
When fishing in Squaw Creek Reservoir, watch out for alligators! Cooling Comanche Peak keeps the lake at a warm 93 degrees, making it an ideal habitat for the gators who love warm water.
- Eastern bluebirds and bobwhite quail love Squaw Creek Park where an ongoing partnership with Glen Rose High School environmental classes is helping the birds return to their natural habitat.
- It’s become a summer tradition for the plant’s North American Young Generation in Nuclear chapter members to take summer interns on a tour of the property to see the dinosaur tracks and the Ancient Tree of Knowledge, whose name was coined by a former intern to honor the massive tree that narrowly escaped being cleared during construction.
- Fish love the warm water of Squaw Creek Reservoir – and so do fishermen. Bassmaster ranked it 86th among the Best Bass Lakes in America in 2015.
- Each reactor operates 24 hours a day, 7 days a week, only taking a break once every 18 months for a nuclear refueling and maintenance outage, when the fuel is unloaded and half of it is replaced with fresh fuel. The other half will return to the reactor after passing a visual inspection to power Texas for one more cycle.
Comanche Peak Units 1 and 2 ranked No. 1 and 2 in the country for net capacity factor (three-year average) for 2009-2011 and 2010-2012.
- Laid end to end, the 200 miles of electrical conduit inside Comanche Peak would stretch from Dallas to Austin.
- An earthquake-proof earth-filled dam separates a second reservoir from Squaw Creek Reservoir. This 367 acre-foot impoundment provides a supply of cooling water for safety systems, including firefighting and safe reactor shutdown.
- The spent fuel cools for at least five years in a pool of water before it is transferred and stored in steel canisters, which are placed inside a steel and concrete dry cask weighing about 300,000 pounds.
- Comanche Peak makes electricity by spinning a turbine generator rotor at 1800 rpm using steam that is generated by heat produced by nuclear fission. Fission is the process of splitting the nucleus of an atom – in this case, the uranium atoms in the fuel rods.
- The reactor vessel – an 8.5 inch thick carbon steel tank that houses the fuel rods – is x-rayed and pressure tested to ensure sound construction.
- The reactor containment buildings – the rounded dome structures – are 265 feet tall, 135 feet in diameter with 4.5 feet thick reinforced concrete walls at the base and 2.5 feet thick reinforced concrete domes.
- In 2014, Comanche Peak’s two units provided 27 percent of the 68,330 gigawatt-hours generation production of Luminant’s fleet.