Fig. 1. All reactors. The median DER net capacity factor of the 96 reactors included in this survey for the three-year period 2018–2020 is 91.33 percent. For the five three-year periods between 1997 and 2011 shown above, 104 reactors were in operation. The 2012–2014 capacity factor includes 100 reactors, and 2015–2017 includes 99 reactors.
Capacity factor is a measure of reliability, and reliability delivers results. The U.S. nuclear power fleet produced about 789.9 TWh of clean electricity in 2020 and ended the year with 94 operating reactors. According to Energy Information Administration data, that’s about 37 percent more electricity than the 576.9 TWh produced in 1990 by a much larger fleet of 112 reactors.
Nuclear News has tracked and analyzed the capacity factors of the U.S. fleet since the early 1980s, before concerted industry efforts yielded unforeseen performance improvements. High nuclear capacity factors are now less an achievement than an expectation. So much so, in fact, that advanced reactors in development today are assumed to be capable of achieving capacity factors above 90 or even 95 percent.
The U.S. fleet has maintained a median capacity factor near 90 percent for 20 years (see Fig. 1), and the median design electrical rating (DER) net capacity factor for 2018–2020, at 91.33, does not disappoint—unless by showing virtually no change relative to the median of 91.34 recorded in 2015–2017. However, this lack of meaningful difference only underscores the consistent reliability of the U.S. fleet.
TerraPower and GE Hitachi Nuclear Energy jointly developed the sodium-cooled Natrium reactor with the turbine hall, nitrate heat storage tanks, and cooling towers separated from the reactor at the back of the site.
The viability of nuclear power ultimately depends on economics. Safety is a requirement, but it does not determine whether a reactor will be deployed. The most economical reactor maximizes revenue while minimizing costs. The lowest-cost reactor is not necessarily the most economical reactor. Different markets impose different requirements on reactors. If the capital cost of Reactor A is 50 percent more than Reactor B but has characteristics that double the revenue, the most economical reactor is Reactor A.
The most important factor is an efficient supply chain, including on-site construction practices. This is the basis for the low capital cost of light water reactors from China and South Korea. The design of the reactor can significantly affect capital cost through its impact on the supply chain. The question is, how can advanced reactors boost revenue and reduce costs?
Unit 3 of the Vogtle plant under construction (Photo: Georgia Power)
To reach President Biden’s goal of cutting U.S. carbon emissions in half by 2030 and to have a net-zero carbon economy by 2050, some environmentalists are reconsidering their opposition to nuclear energy’s role as a climate crisis solution. According to the article, The controversial future of nuclear power in the U.S., from National Geographic, nuclear power has a lot going for it. Its carbon footprint is equivalent to wind, less than solar, and orders of magnitude less than coal. Nuclear power plants take up far less space on the landscape than solar or wind farms, and they produce power even at night or on calm days.
Two of the state’s six nuclear plants nearly closed in 2016, but legislative action saved them. Now two more are at risk.
If there is one U.S. state you might think would be on top of the nuclear-plant-retirement problem, it’s Illinois: With 11 power reactors, more than any other state, it is number one in nuclear generating capacity. In 2019, 54 percent of its in-state generation came from nuclear power. So why, at this writing in mid-April, does Illinois still face the possibility of losing two of its nuclear plants later this year?
Salem Nuclear Power Plant as photographed from Delaware Bay.
When a nuclear power plant closes, here is what happens:
Thousands of people lose their jobs. The local economy nosedives. Air pollution increases. Reliance on natural gas, often bought from out-of-state, goes up. Electricity on the grid becomes less reliable with the loss of the most reliable source of power. And electric prices can even rise.
A screenshot from the Kurzgesagt YouTube video
The German animation studio Kurzgesagt released a new video to its English YouTube channel last week to answer the question, “Do we need nuclear energy to stop climate change?” The studio’s channel on YouTube is self-described as a small team working to make science look beautiful. Its videos discuss a variety of scientific, technological, philosophical, and psychological questions, and it has more than 14 million subscribers. The channel recently discussed the question of deaths caused by radiation—spoiler alert, nuclear is among the safest of all energy production.
Statement from American Nuclear Society President Mary Lou Dunzik-Gougar and CEO Craig Piercy
On behalf of America’s nuclear engineers and scientists, the American Nuclear Society welcomes the release of President Biden’s American Jobs Plan. We are thrilled to see the inclusion of America’s largest carbon-free energy technology, nuclear energy, in Biden’s infrastructure plan to reenergize and decarbonize our economy.