By Julio Adame and Brenna Wolfe | Published in and Valve Magazine

Nuclear power once seemed an unlikely partner to the idea of clean energy; nuclear doesn't appear to be a factor in providing cleaner energy and reduced air pollution. However, this source of energy has been a safe, reliable source of carbonfree electricity for decades. Even when the sun isn't shining or the wind isn't blowing, nuclear power keeps producing carbon-free power, using technologies that focus on safety, reliability and economical operation. To better understand why it's a necessary resource in meeting our clean energy needs, we must understand the origins of the industry.

A Reliable Old Friend

With 94 commercial operating reactors at a combined capacity of 97,154 MWe, the United States has the largest nuclear fleet in the world, producing more electricity from nuclear power than any other single country and contributing more than 30% of the world’s nuclear electricity generation capacity. As of 2019, the next closest country is France with 56 reactors generating 61,370 MWe of power – in total, nuclear currently accounts for more than 70% of their electricity generation needs. Other countries, such as China and India, continue to build and push for nuclear power, hoping to take advantage of the most reliable clean energy source.

The idea of nuclear power seems an unlikely partner to the idea of clean energy – on the surface it may seem that nuclear power isn’t a factor in providing cleaner energy and reducing air pollution, but it has been a safe and reliable source of carbon-free electricity for decades. Even when the sun isn’t shining or the wind isn’t blowing, nuclear power is there to keep producing carbon-free power, using technologies that focus on safety, reliability, and economic operation. To better understand why it’s is a necessary resource in meeting our clean energy needs, we must understand the origins of the nuclear power industry.

The story of America’s nuclear power industry includes a young Polish immigrant named Hyman G. Rickover – or as he is better known, Admiral Rickover – whose actions fathered the United States Nuclear Navy. Admiral Rickover served in the U.S. Navy from his graduation from the United States Naval Academy in 1922 until his retirement in 1982, and spent most of his career advocating for nuclear technology and power. It is because of Admiral Rickover that commercial nuclear power plants and the U.S. Naval Submarine program have their beginnings intertwined with each other; during a visit to Oak Ridge National Laboratory in 1946, Admiral Rickover observed their work on a nuclear electric generating plant, which inspired his vision for a fleet of submarines and ships powered with nuclear energy. As he began to share his vision with others in the U.S. Navy, he garnered support needed to begin development on nuclear power for submarine propulsion and for commercial electricity operation. Admiral Rickover was responsible for overseeing the development of both the nuclear-powered submarine and the first full scale commercial nuclear power plant. In 1949, he continued his focus in nuclear by serving in two government roles simultaneously as both the Director of the Nuclear Power Division, Bureau of Ships and the Chief of the Naval Reactor Branch, Reactor Development Division, in the Atomic Energy Commission, which was the predecessor to today’s Nuclear Regulatory Commission.

Safety and discipline were of the utmost importance to Admiral Rickover; in the development of the nuclear submarine, he created a culture of accountability and procedure that ultimately led to the success of the naval and civilian nuclear power programs. His maniacal focus on safety and reliability for nuclear machinery led to him demanding that even completely built equipment and prototypes be discarded if they were considered flawed or had poor workmanship. Engineers working for Admiral Rickover adopted this attitude, using careful and precise engineering in the development of the first full scale nuclear power plant. Because of this, Admiral Rickover can be credited as the force behind creating a safety culture that has led to the lack of any major U.S. Navy reactor accidents. His intense focus on safety and reliability carried over as the naval nuclear program gave birth to the civilian nuclear power program; the first full scale nuclear power plant for civilian use, the Shippingport Nuclear Power Plant, started up in 1957 and operated until 1982. The success of the Shippingport Nuclear Power Plant led to the building of larger, more economical nuclear power plants that could produce more electricity to power more homes and businesses.

Today, nuclear power prevents 573 million tons of carbon dioxide emissions each year. It employs over 475,000 full time direct and secondary jobs, and has a stellar OSHA safety record, with significantly lower recordable incidents than other industrial workplaces. Over 28 states utilize nuclear power plants to help reduce carbon emissions; In fact, nuclear generates 55% of the power in Illinois, 50% of the power in South Carolina, and 40% of the power in Connecticut. Since the 1990s, nuclear power has been operating at over an 80% capacity factor, a measure which indicates how fully a unit’s capacity is used, and in 2019 achieved 93% capacity factor, making it significantly more reliable than other forms of power generation. The capacity factor reliability helps ensure critical operation of infrastructure such as hospitals, airports, schools, and water/sewage plants. Comparatively, renewables such as solar and wind had a capacity factor of 24% and 34% respectively in 2019. This gap is why nuclear is so important in complementing renewables like solar and wind.

A Brighter Future

Admiral Rickover wasn’t the only one looking towards the future in the 1940s; starting with the invention of the transistor in 1947, the digital revolution developed alongside the nuclear industry and continues to rapidly accelerate. In the 70 years since the launch of the USS Nautilus (the first nuclear powered submarine), we have moved from transistors to pagers, pagers to smart phones, and smart phones to virtual reality technology. As we become more reliant on technology and our populations continue to grow, it is highly likely that power generation will have to rise to meet our increasing demands. On top of the increased demand, more and more countries are committing to be carbon free or carbon neutral within the next 30 years. With mandates like California’s goal to ban sales of gas-powered cars by 2035 applying pressure to the power industry for cleaner, more efficient systems, it has become more and more apparent that achieving carbon reduction goals is going to need the reliability of nuclear.

As the largest carbon free energy source in America, nuclear is a giant among other clean energy sources. In 2020, nuclear produced 55% of America’s clean energy, and 20% of all American energy. This does not mean that nuclear needs to be the singular answer to America’s carbon woes – in fact, the reliable nature of nuclear pairs perfectly with renewables which often rely on certain conditions to produce power. This reliability increases the flexibility of our power grid, allowing for large shifts like the potential virtual power grid proposed in California and smaller scale operations like microgrids and vehicle grids.

The nuclear industry also continues to rise to meet the challenge of increased safety, reliability, and cost effectiveness, developing technology to meet growing demands and surpass future expectations. Every stage and phase of the nuclear process is constantly being examined for potential advancements and improvements, ranging from process innovations like using 3D scanning for plant inspections, utilizing augmented / virtual reality products for training and troubleshooting, and producing hydrogen from nuclear processes, to product innovations like new fuel types, fail-proof reactor designs, and small modular / advanced reactors.

Small modular reactors (SMRs) and Advanced Reactors (ARs) represent both the future of the nuclear industry and the opportunity for reliable, sustainable power, even in areas that may not otherwise have access to other renewable sources. Enabled by government programs, these reactors have a lower capital investment, a smaller physical footprint, and a larger variety of site options, all of which have been long term issues of the conventional nuclear power industry. This flexibility means they can also be used in conjunction with other renewables, maximizing potential space and output power, even when conditions are less than ideal for other power sources like wind and solar. There are several designs currently circulating in the market, each of which has their own unique features and advantages, though all of them possess the same obsessive eye for safety that Admiral Rickover fostered in the commercial and naval nuclear power industry.

Companies like NuScale, TerraPower, GE-Hitachi, X-energy, Oklo, Kairos, the Ultra Safe Nuclear Corporation (USNC), and others, all have reactors that can be deployed by the late 2020s or the early 2030s. These reactors live up to the imperative that we have a clean, safe and reliable source of carbon-free electricity. NuScale’s Power Module is the first NRC-approved SMR design, and has received a cost-share award from the Department of Energy under the Carbon Free Power Project. Other SMR and AR designs are further away but still viable in the next 10 years. Fast Neutron Reactors (FNRs) have better fuel efficiency and longer refueling cycles, with some even being able to run off recycled fuel from traditional power plants. Other options, like high temperature gas-cooled reactors (HTRs) and modified light water reactors (LWRs), use more traditional methods, but still push the industry mindset of innovation forward.

There is no one solution to meeting America’s carbon goals or to an entirely clean energy grid. But the demand for safe, clean, and reliable energy will only increase with the population and technological advancements, meaning that we need to take steps now to preserve our future. Renewables alone are not enough to meet the needs of our grid while also hitting carbon emission goals, as they lack the reliability that nuclear offers to the industry at large. By supporting initiatives like small modular and advanced reactors with renewables, a more sustainable future is within our grasp.

This article originally appeared in the Winter 2021 issue of VALVE Magazine (www.valvemagazine.com), published by the Valve Manufacturers Association (www.vma.org).

A chart showing the status o US nuclear power plant licenses and announced long-term operational plans.

In December 2019, Turkey Point Units 3 and 4 were granted SLR approval, establishing the two reactors as the first to be licensed for 80 years in the U.S. A few months later, in March of 2020, Peach Bottom Units 2 and 3 also received SLR approval.

Surry Units 1 and 2 SLR applications are currently under review, while North Anna’s two units and Oconee nuclear station’s three units have future submittals scheduled in late 2020 and 2021, respectively. Duke Energy has announced plans to seek license renewal for its remaining eight nuclear reactors following the Oconee SLR application submittal.

Addressing Aging Effects

The NRC’s Generic Aging Lessons Learned for Subsequent License Renewal (GALL-SLR) Report and Standard Review Plan for Review of Subsequent License Renewal for Nuclear Power Plants (SRP-SLR) documents provide detailed guidance on the SLR review process and license renewal requirements. As part of the application for a second renewal, a plant must demonstrate that it can operate safely and efficiently in compliance with NRC requirements for the extended period of operations.

Nuclear plants that have passed their original 40-year lifetime and are now operating in an initial license renewal period have established aging management programs (AMPs) to address the impacts of operating beyond the initial 40-year mark, as well as past the new 60-year mark. These programs analyze all aspects of a plant for projected aging components, identify any potential incidents that may arise, and include research and development (R&D) efforts into aging solutions. Two fundamental AMP objectives are to ensure plant safety and implement efficiency improvements—both of which align with the “Delivering the Nuclear Promise” (DNP) industry initiative.

Changing Market Dynamics for Nuclear Suppliers

DNP has been one of the most impactful U.S. nuclear milestones in recent years, transforming plant operations across the fleet and reshaping the domestic nuclear landscape. Led by the Nuclear Energy Institute (NEI), a nuclear trade association, DNP is an industry-wide strategy that aims to promote operational efficiency while increasing safety and reliability.

A key tenet of DNP is reducing the generating expenses of the U.S. nuclear industry to combat economic pressure created by low natural gas prices and low growth in electricity demand. Its target was an aggressive 30% cost reduction from 2012 through 2020, and plants are on track to achieve that goal. Despite gains in plant profitability and a positive uptick in the U.S. nuclear outlook, DNP has caused negative effects on the supply chain—the industry’s sustained focus on achieving cost-savings and efficiencies has had a substantial impact on plant maintenance strategies and overall spending.

Most U.S. nuclear plants elect to maintain their base of originally installed equipment whenever possible. If replacement becomes essential (such as due to obsolescence), common practice is to source similar fit-form-function alternatives that minimize the impact of the change, rather than implementing modifications that are typically more expensive due to component procurement as well as engineering and installation costs. With license expirations and permanent closure not far off, plants have been less inclined to invest in costly, transformational modifications requiring longer timelines to realize full value.

Consequently, the supply chain has focused its efforts on aligning portfolios with plant needs, maintaining legacy component offerings and products that offer only incremental improvements to reliability. These market conditions have created a challenging supply chain environment that has driven some nuclear suppliers to curtail R&D on nuclear products, scale back focus on nuclear customers, or drop nuclear quality assurance programs.

Despite higher upfront costs, modernization of plant equipment and systems holds tremendous potential to elevate progress toward DNP’s efficiency and profitability goals, and with the rise of SLRs fast approaching, plants will be afforded the long-term investment horizon needed to justify major modernization programs. The supply chain must be prepared to fulfill the need for large quantities of the latest technology that satisfy all nuclear safety-related quality, environmental, and reliability requirements.

Plant Modernization

The most impactful upgrade to nuclear plants will likely be the transition from analog control systems to digital. Paul Phelps, director of Nuclear Projects Technical Support (SLR) License Renewal for Dominion Energy’s SLR project at North Anna and Surry stations, commented, “We are upgrading our plants around the next generation of operators, engineers, and maintenance personnel. A modernized control room will put significantly more information in their hands to assess the plant’s condition.”

Adoption of digital control systems for non-safety related applications has already shown marked progress in the industry. The D.C. Cook plant recently finished upgrading its non-safety control systems to a digital system. In July 2019, Purdue University received licensing for its nuclear research reactor, PUR-1, an entirely digital instrumentation and control system.

Along with digital control systems, advanced condition monitoring systems will be used to optimize maintenance decisions and prevent component degradation. The NRC’s GALL-SLR and SRP-SLR identified condition monitoring and assessment as potential challenges in post 60-year operations, and the nuclear industry is poised to increase implementation of digital technologies designed to streamline these operations.

Quinn Reynolds, a nuclear power engineering manager for engineering firm Sargent & Lundy, acknowledged, “SLRs will lead to significant modernization programs for nuclear plants; the use of advanced diagnostics and sensors will optimize decision-making. Installing this technology will require vendors to support plants with qualification of equipment, configuration and programming of hardware and software, meeting cybersecurity requirements, and training.”

Resolving Supply Chain Gaps

In response to the industry’s changing market dynamics and nuclear plant needs, suppliers must adapt—quickly. Plant closures and the DNP initiative have created significant headwinds for U.S. nuclear suppliers. Fewer upgrade projects, lower spare parts volume, and shrinking profit margins have driven some suppliers to abandon their long-term nuclear strategies. This retraction of supply chain capacity and capability is at odds with what will be needed to support the expected wave of plant investment resultant from SLRs.

Despite these difficulties, some suppliers are taking proactive steps to bridge supply chain gaps by adapting business strategies and bringing innovative offerings to market.

Analysis and Measurement Services Corp. (AMS) is a nuclear engineering consulting firm headquartered in Knoxville, Tennessee. President and CEO H.M. “Hash” Hashemian described AMS’s strategy for supporting plants as they prepare for SLR: “AMS is supporting license extension activities with advanced testing services as well as leading-edge technology. Over the last 10 years, AMS has developed in-situ low-voltage cable condition monitoring technologies and have successfully applied them to nuclear power plants to identify if and when aged cables must be repaired or replaced. We can sit in the control room and send signals through cables and diagnose from the reflected signal if and where a cable insulation material may be faulty and what to do to fix it. Additionally, online monitoring to catch drift of pressure, level, and flow transmitters is at the forefront of the nuclear industry’s efforts today to save calibration costs. This will save plants over 90% of the efforts currently spent on manual transmitter calibrations.”

Curtiss-Wright, a power industry supplier, has expanded its portfolio with digital platforms that fulfill plant efficiency and maintenance objectives. “Despite nuclear industry challenges, SLRs present a unique opportunity for suppliers. Licensing extension has renewed the industry’s focus on R&D and innovation—particularly in the digital space,” commented Kurt Mitchell, vice president and general manager of Curtiss-Wright’s Nuclear Division. “In line with plant-wide automation and modernization goals, Curtiss-Wright has developed robust, flexible, and digitally diverse control system offerings for non-safety-related and safety-related applications. Our portfolio features a balance of innovative technologies—such as equipment anomaly detection and advanced pattern recognition—and proven solutions like our condition monitoring and thermal performance platforms.”

Comparing Real-World Values

The first plants to complete SLRs will pioneer the transition toward highly efficient, reliable, and competitive nuclear plants that provide green baseload energy. License expirations will force an inflection point for the industry as utilities decide to ride out their existing licensing terms until closure or pursue SLRs. These critical decisions will be motivated by the public’s demand for large-scale, reliable, green energy and the ability of nuclear to safely generate electricity at competitive rates.

If plants trend toward closure, the industry will see supplier abandonment and consolidation, with the remaining suppliers concentrated on supplying like-for-like product replacements at the lowest possible cost with just-in-time delivery. If the direction shifts toward extended operation and modernization via SLRs, it will drive increased innovation and collaboration between suppliers and utilities, modernization of equipment and systems, and streamlining of plant processes—all of which will set the stage for an unprecedented industry revival.