I&C with Tighe Smith: The Nervous System of a Nuclear Reactor
RSS Feed Key Takeaways
- Instrumentation and control (I&C) functions as the critical nervous system of every nuclear reactor, yet it remains largely invisible to the public.
- Tighe Smith explains how Paragon Energy Solutions reverse-engineers obsolete circuit cards using 1970s components to keep existing plants running safely.
- Nuclear power plants often carry around $100 million in spare parts inventory to ensure reliable operations and rapid replacements.
- The PEAKS program successfully brokers approximately 3,000 spare parts a year between 94 nuclear reactors across the United States with same-day or next-day shipping.
- Digital upgrades in nuclear facilities only make economic and operational sense if a plant is planned to run for 20 or more additional years.
ABOUT THIS EPISODE
What keeps a nuclear power plant running safely after 50 years? Tighe Smith knows better than almost anyone. As Chief Nuclear Officer at Paragon Energy Solutions — now part of Mirion Technologies following a $585 million acquisition — Tighe has spent his career in nuclear instrumentation and control (I&C): the nervous system of every reactor.
In this episode, we get into what I&C actually does, why some of the control systems inside U.S. nuclear plants predate the transistor, how Paragon reverse-engineers obsolete circuit cards with 1970s components, and how they broker spare parts between 94* reactors across the country — 3,000 parts a year, same-day or next-day shipping. Plus: the workforce reality of digital upgrades, advanced reactor design, and a culture built on three P's and three C's.
WHAT YOU'LL LEARN
- What instrumentation and control (I&C) is and why it's the most invisible-but-critical system in any nuclear plant
- Why some U.S. reactor control systems still use technology from before the transistor was invented
- How Paragon reverse-engineers obsolete circuit cards — and why rotating a transistor 90 degrees can introduce failure modes
- The PEAKS program: how 3,000 parts move between 94 reactors every year
- Why nuclear plants carry $100 million in spare parts inventory (and why it's worth it)
- The analog vs. digital debate: why a digital upgrade only makes sense if you're planning to run a plant for 20+ more years
- How I&C changes for advanced reactors — simpler safety systems, new challenges
- Paragon's Three P's (Present, Persistent, Passionate) and Three C's (Competence, Commitment, Character)
CONNECT WITH PARAGON/MIRION
LinkedIn (Tighe Smith): Search "Tighe Smith Paragon Energy Solutions"
Paragon Energy Solutions (now Mirion Technologies): https://www.mirion.com/
Mirion Technologies LinkedIn: https://www.linkedin.com/company/mirion-technologies/
RESOURCES MENTIONED
- HIPS (Highly Integrated Protection System) — Paragon's FPGA-based digital safety platform
- Core Vision — Paragon's neutron monitoring product line
- PEAKS — Paragon's nuclear spare parts network program
- 10 CFR 50 — NRC domestic licensing requirements
- Three Mile Island accident and lessons for human-machine interface design
- NRC maintenance and testing requirements for nuclear facilities
JOIN THE NUCLEAR WORKFORCE
The nuclear industry is growing, and companies like Paragon/Mirion need engineers, technicians, and trades workers with the right skills and the right character.
Are you a skilled professional interested in nuclear? Nuclear Talent Scout connects candidates with nuclear employers.
Apply here: https://nucleartalentscout.com/apply/
ABOUT NAKED NUCLEAR
Naked Nuclear is the podcast that pulls back the curtain on the nuclear industry — no hype, no fear, just real conversations with the people doing the work. Hosted by Danielle Allen.
Website: www.nakednuclear.com
Frequently Asked Questions
What is nuclear instrumentation and control (I&C)?
Instrumentation and control (I&C) is the system of sensors, controllers, and circuitry within a nuclear power plant that monitors and regulates reactor operations, essentially acting as the plant's nervous system.
How does Paragon Energy Solutions handle obsolete nuclear parts?
Paragon reverse-engineers outdated circuit cards and components, carefully recreating 1970s-era technology while accounting for intricate failure modes like the orientation of a single transistor.
Why do nuclear power plants keep millions of dollars in spare parts inventory?
Plants carry up to $100 million in spare parts inventory to prevent costly downtime and ensure that critical replacement components are immediately available when needed.
When does a digital upgrade make sense for a nuclear reactor?
A digital upgrade is typically only pursued when plant operators have concrete plans to run the facility for at least 20 more years, given the high costs and rigorous regulatory requirements.