What digital instrumentation upgrades are essential for extending the life of aging nuclear reactors?

Digital instrumentation and control (I&C) upgrades have become a key enabler for nuclear power plants seeking to extend their operational lifespans. As global fleets of pressurized water reactors (PWRs) and boiling water reactors (BWRs) approach or exceed 40 years of service, replacing aging analog neutron flux monitoring systems and reactor safety controls with digital platforms is proving critical to safety, efficiency, and regulatory compliance.

Mirion Technologies Inc. and Westinghouse Electric Company recently announced a strategic partnership to deploy digital ex-core Nuclear Instrumentation Systems (NIS) powered by Mirion’s proTK platform. Similarly, Framatome’s TELEPERM XS and other vendor platforms are reshaping how legacy plants approach life extension beyond their original design lifespans. These systems are being adopted not just for performance benefits, but also to meet new regulatory expectations, rising ESG standards, and the challenges of component obsolescence.

What digital safety and control upgrades are being prioritized to replace aging nuclear monitoring systems?

Among the most widely adopted solutions are digital neutron flux monitoring systems, digital reactor protection systems (RPS), and turbine and safeguards control units. Framatome’s TELEPERM XS platform offers a fully digital, modular solution for core protection, engineered safeguards, and balance-of-plant controls. Built on programmable logic controllers (PLCs) and field-programmable gate arrays (FPGAs), the system is designed for long-term maintainability and compatibility with evolving regulatory standards.

Mirion Technologies’ proTK system, selected by Westinghouse for global deployment in both Westinghouse- and Combustion Engineering-designed reactors, represents a digital replacement for analog neutron flux monitoring drawers. These legacy systems, some dating back to the 1960s, are increasingly expensive to maintain and difficult to integrate with modern control rooms. The proTK platform is positioned as a drop-in solution that minimizes operational disruption and retraining requirements, making it attractive for utilities pursuing license renewal or lifetime extension.

Digital systems also offer advantages in terms of real-time diagnostics, automated fail-safes, and predictive maintenance—enhancements that were not feasible with legacy analog infrastructure.

How are global regulatory frameworks encouraging the transition to digital I&C modernization in nuclear facilities?

Regulators are playing a central role in accelerating the shift from analog to digital systems. In the United States, the Nuclear Regulatory Commission (NRC) has implemented a modernization roadmap that enables digital I&C systems to be licensed more efficiently while maintaining safety margins. The NRC’s Digital I&C Regulatory Infrastructure Program provides a structured path for incorporating digital components into existing plants, with emphasis on risk-informed decision-making and cybersecurity assurance.

Internationally, agencies such as the International Atomic Energy Agency (IAEA) and national nuclear safety authorities in Canada, France, and South Korea are adopting similar guidance. These frameworks recognize the challenges of component obsolescence and recommend proactive digital migration strategies to ensure uninterrupted reactor operation.

For utilities pursuing 60- or 80-year license extensions, digital upgrades are often not just recommended but required—especially for critical systems tied to core protection, power regulation, and emergency shutdown.

What operational and economic benefits are being realized through digital instrumentation replacements?

Replacing legacy analog systems with digital platforms provides several measurable benefits. These include improved system reliability, lower lifecycle costs, reduced calibration needs, and easier access to spare parts. Unlike analog systems, which often require manual signal checks and paper-based documentation, digital systems log all data in real time, allowing operators to monitor reactor status with greater precision and respond proactively to anomalies.

Mirion’s proTK system, for example, allows operators to integrate digital signal processing into existing infrastructure. The system is engineered to fit within the same racks and cabling used by older neutron flux drawers, minimizing downtime during installation. Framatome’s TELEPERM XS has been successfully deployed in over 90 nuclear plants globally and is praised for its modularity, cybersecurity features, and ability to integrate with plant-wide diagnostic systems.

Digital platforms also simplify regulatory reporting and performance benchmarking, offering traceability and auditability that analog systems inherently lack.

How do digital instrumentation upgrades contribute to plant life extension and long-term nuclear asset optimization?

Digital I&C modernization is no longer viewed as optional—it’s now a fundamental pillar of asset management and economic optimization for nuclear utilities. Many aging plants are extending operations past 60 years, and without digital upgrades, continued operation becomes both technically challenging and economically inefficient.

Analog instrumentation is not only prone to signal drift and failure, but also often unsupported by OEMs. Replacement parts are increasingly hard to find, and expertise in maintaining these systems is dwindling due to workforce attrition.

Digital upgrades, on the other hand, enable long-term service agreements, software upgradability, and compatibility with other modernization efforts such as digital control rooms and AI-based predictive analytics. These enhancements contribute to increased plant capacity factors, lower unscheduled outage rates, and improved staff productivity.

From an ESG perspective, modernized nuclear plants are better positioned to serve as clean baseload energy sources, aligning with national and international decarbonization targets.

What implementation risks and integration challenges must nuclear operators manage during digital upgrades?

Despite their advantages, digital I&C upgrades present several integration challenges. These include ensuring compatibility with legacy plant systems, validating safety-critical software, and meeting cybersecurity requirements. Utilities must coordinate with OEMs, regulators, system integrators, and third-party cybersecurity auditors to build a comprehensive modernization plan.

Project risk also stems from timing: many upgrades are scheduled during planned outages, leaving narrow implementation windows. Failure to execute within these windows can delay reactor restart and incur significant costs.

To mitigate these risks, utilities are increasingly adopting phased deployment strategies, starting with non-safety systems and expanding into safety-class components once regulatory confidence is established. Vendor support, simulation tools, and plant-specific modeling are critical for derisking implementation and achieving schedule certainty.

What are institutional investors and analysts saying about digital I&C upgrades in the context of nuclear modernization?

Institutional sentiment toward digital instrumentation modernization is strongly positive, especially in the context of life-extension and decarbonization investments. Analysts note that utilities investing in digital upgrades demonstrate better operational resilience, compliance posture, and long-term cost control—factors that improve their standing with credit rating agencies and attract ESG-conscious capital.

The recent surge in partnerships—such as the Mirion–Westinghouse alliance and Framatome’s TELEPERM XS global deployment—signals growing market momentum. Investors see these projects not just as technical improvements, but as structural catalysts for extending nuclear viability into the 2070s.

From a valuation perspective, companies providing modular, drop-in solutions with proven deployment records are seen as outperformers in the evolving nuclear supply chain.

How might deployment timelines and early results shape the pace of digital modernization in the global nuclear industry?

Looking ahead, the success of initial deployments will determine how quickly digital upgrades scale across the industry. Early installations of systems like proTK and TELEPERM XS will be closely monitored for performance reliability, training efficiency, and regulator feedback.

Utilities that demonstrate smooth digital transitions may accelerate upgrades across other reactor units, while OEMs could expand into adjacent markets such as research reactors, medical isotope production facilities, and emerging SMR platforms.

By 2026, analysts expect digital instrumentation to become a standard requirement in most plant license extension applications. Utilities that delay modernization may face rising maintenance costs, insurance premiums, and compliance hurdles, putting them at a disadvantage both operationally and financially.