Features

The facts, once known, were uncomplicated. At Taishan-1 in China—the first Framatome EPR to be commissioned—operators detected an increase of fission product gases within the primary coolant circuit sometime after the reactor’s first refueling outage in October 2020. The cladding on a handful of the more than 60,000 fuel rods in the reactor had been breached, posing an operational issue—but not a public safety issue—for the plant.

One of the biggest challenges in training for incidents and emergencies that involve high-radiation-dose hazards is balancing between realism and safety. To be truly prepared for the realities of real-world nuclear and radiological emergencies, responder personnel need experience against those hazards but without introducing additional and very personal risks associated with unnecessary radiation exposure. The difficulty is in figuring out how we can achieve a level of realism that encompasses the entire process, from the initial detection of a hazard or threat, through its characterization, to recommending actions and leadership decision-making.

Molten salt reactor technology first gained popularity in the 1960s, through the Molten Salt Reactor Experiment program at Oak Ridge National Laboratory. Now, decades later, a technology known as the molten salt nuclear battery (MsNB) is being developed to support the growing need for carbon-free, reliable, independent, and compact sources of small-scale heat and electrical power.

Online monitoring (OLM) technology can be used in nuclear power plants as an analytical tool to measure sensor drift during plant operation and thereby identify the sensors whose calibration must be checked physically during an outage. The technology involves a procedure to (1) retrieve redundant sensor measurements from the process computer or through a separate data acquisition system, (2) calculate the average of these measurements and the deviation of each sensor from the average, and (3) identify any sensor that has deviated beyond its predetermined monitoring limit.

Public discourse on energy and climate increasingly includes nuclear energy, but how has that affected public opinion? The answer: a lot. A national public opinion survey conducted in May found that support for nuclear energy has rebounded, and politics, in part, may offer a window into why. For example, now Biden and Trump voters support nuclear energy about equally. Trump voters care more about affordable and reliable electricity. Biden voters care more about climate change, and their support is driven by perception of need. Perception of need is boosted by climate change, recent energy supply problems, and Democratic leadership endorsements. The importance of Democratic leadership endorsements is shown in the Obama bump in 2010 and the Biden bump in 2021. In both cases, the increase in overall support for nuclear is largely attributable to increased support among Democrats.

The survey, with 1,000 nationally representative U.S. adults, has a margin of error of plus or minus 3 percentage points and was conducted by Bisconti Research Inc. with Quest Global Research Mindshare Online Panel. The report includes trend data going back 38 years.

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.

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?

At present, more than 20 commercial nuclear power plants in the United States have entered the decommissioning process, and many indicators point to a coming wave of additional plant closures. Indeed, with increasing numbers of plants terminating operations due to unfavorable market conditions, some voices have deemed this the “age of decommissioning.”

Regardless of whether a plant shuts its doors earlier than antici­pated or seeks a life extension through relicensing, all plants eventually close. When they do, the closure sets off a wave of economic impacts ranging from minor disruptions to severe and long-lasting harm.

When on May 7, 2013, the Kewaunee nuclear power plant in rural Wisconsin was shut down, it took with it more than 600 full-time jobs and more than $70 million in lost wages, not including temporary employment from refueling and maintenance outages. Taking into account indirect business-to-business activity, the total economic impact of the closure of the single-unit pressurized water reactor was estimated to be more than $630 million to the surrounding three-county area.

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?

The health and safety of the public and protecting people from the consequences of a significant release of radioactive material has been a top priority since the early days of the civilian nuclear energy program. After World War II, it was realized that the core inventory of radionuclides is a potential hazard. From this knowledge, emergency planning zones (EPZs) for nuclear power plants were established.

To build a next-generation nuclear reactor, you can teach it how to build itself

The nuclear reactors currently in operation in the United States are beginning to gray around the temples. Built decades ago using technology developed during the middle of the 20th century, these reactors have safely and reliably powered homes and businesses, but they produce waste that must be disposed of properly.

Nuclear power plants not only provide the nation’s largest source of carbon-­free electricity, they also can operate 24 hours a day, 365 days a year to augment intermittent renewables such as wind and solar. Further, studies show that nuclear energy is among the safest forms of energy production, especially when considering factors such as industrial accidents and disease associated with fossil fuel emissions. All said, nuclear has the potential to play a key role in the world’s energy future. Before nuclear can realize that potential, however, researchers and industry must overcome one big challenge: cost.

A team at Idaho National Laboratory is collaborating with experts around the nation to tackle a major piece of the infrastructure equation: earthquake resilience. INL’s Facility Risk Group is taking a multipronged approach to reduce the amount of concrete, rebar, and other infrastructure needed to improve the seismic safety of advanced reactors while also substantially reducing capital costs. The effort is part of a collaboration between INL, industry, the Department of Energy’s Advanced Research Projects Agency–Energy (ARPA-­E), and the State University of New York–Buffalo (SUNY Buffalo).

Sooner or later, any discussion of the future of the role of nuclear power leads to the question, “What are you going to do with the waste?” Nuclear technology professionals recognize that there are good solutions available for the management and disposal of nuclear waste, but implementing them requires overcoming societal and political barriers that have proven daunting in this country. Currently, the United States has a nuclear waste policy, but the federal government lacks the will to implement it or change it. The past decade has been extremely frustrating to those dedicated to addressing waste issues here and now, rather than kicking them down the road. Prospects for the next decade are uncertain, at best.

The Fukushima Daiichi site before the accident. All images are provided courtesy of TEPCO unless noted otherwise.

It was a rather normal day back on March 11, 2011, at the Fukushima Daiichi nuclear plant before 2:45 p.m. That was the time when the Great Tohoku Earthquake struck, followed by a massive tsunami that caused three reactor meltdowns and forever changed the nuclear power industry in Japan and worldwide. Now, 10 years later, much has been learned and done to improve nuclear safety, and despite many challenges, significant progress is being made to decontaminate and defuel the extensively damaged Fukushima Daiichi reactor site. This is a summary of what happened, progress to date, current situation, and the outlook for the future there.

In 2015, we wrote an article for Nuclear News analyzing the history of commissioners appointed to the Nuclear Regulatory Commission and assessing their backgrounds, experience, and qualifications at the time of their appointment. At the time, ANS had not established a formal position statement on NRC commissioner appointees. Our article provided an objective assessment of historical patterns and was used to develop ANS position statement #77, The Nuclear Regulatory Commission (2016). This article draws upon the 2015 article and provides updated data and analysis. Also, the recommendations of the position statement are applied to the current vacancy on the commission.

Students display items they received at a STEM workshop sponsored by Exelon. Photo: Exelon.

The landscape of Exelon Generation’s nuclear business has continued to evolve—even before the complications of a pandemic—but people will always remain the core focus. Our employees and our future employee pipelines are changing almost as fast as technology, which is why the development of the workforce, both present and future, along with the transfer of knowledge across all departments and levels of the organization, must remain adaptable and advance as well.

Fusion devices have yet to sustain a burning plasma and produce usable energy, so it should come as no surprise that there is not yet a framework for regulating commercial fusion energy.

Fusion and fission are two very different ways to release nuclear energy. But how different could their regulation be? There are many possible answers to two central questions: Who will regulate commercial fusion (in the United States, that authority could reside with the Nuclear Regulatory Commission or an Agreement State operating under NRC oversight), and what aspects of a fusion plant will they regulate?