Nuclear power plants approaching license expiration are faced with three options: obtain initial license renewal to continue operations (nine U.S. units have not yet received an extension of their initial license), obtain subsequent license renewal, or discontinue operations. Nuclear plant equipment suppliers hang in the balance, as investments in new technology hinge on the industry’s long-term prospects.

By 2040, more than half of the U.S.’s 95 operating reactors will have reached the end of their current license period. Over the past year, four nuclear reactors have received subsequent license renewal (SLR) approval. Seven reactors have pending applications currently under review or scheduled for submission by the end of 2021, and eight additional reactors have announced plans to submit SLR applications. This recent SLR activity, however, accounts for only 20% of the country’s operating nuclear reactors.

As current reactor licenses move closer to expiration, the industry can expect to see significant changes as the U.S. nuclear fleet modifies operations to satisfy regulatory requirements and prepares for a substantial extension of plant life. Nuclear suppliers also face an imminent challenge: adapt to changing market dynamics in support of nuclear plant SLR needs.

Nuclear Power Plant Licenses

The U.S. Nuclear Regulatory Commission (NRC), the country’s regulating body for nuclear power operations, dictates that all nuclear reactors require a license to operate. These reactor licenses hold an initial term of 40 years, and the majority of operating U.S. commercial nuclear power plants have obtained an initial license renewal to extend reactor lifetime from 40 to 60 years. These plants will reach the end of their respective licensing periods as early as 2026 (Indian Point 3’s initial license renewal expires in 2025 but it will close early in 2021). As license expiration dates draw nearer (Figure 1), plants have begun preparations for a second renewal of their licenses, also known as an SLR. These subsequent renewals extend a reactor’s operations from 60 to 80 years, effectively doubling the original licensed lifespan.

1. This chart shows the status of U.S. nuclear power plant licenses and announced long-term operational plans. Source: Curtiss-Wright

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.”

SLRs Create Opportunities

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. ■

Rob Gormley is vice president of Business Development, Jenn Sinkiewicz is communications specialist, and Brenna Wolfe is technical writer with Curtiss-Wright’s Nuclear Division.