Because of nuclear regulation, nuclear plants can only use established, demonstrated technologies. This resulted in nuclear plants being designed with analog instrumentation and control (I&C) systems. These systems are now obsolete and need to be upgraded. There is a small niche market for replacing older analog instrumentation with "new" analog instrumentation. However, the control systems are being replaced with digital. There is a "fly in the ointment" to nuclear plant I&C upgrades and that is the time it takes from the original design to the licensing approval process to the actual installation. The time frame can be 10 years or more depending on the scope of the upgrade. I am aware of a nuclear plant that is replacing its obsolete I&C system with a "modern" digital system. However, because of the extensive delay from the time the system upgrade was awarded to the time the system is being installed, the DCS that was state-of-the art at the time of award is now obsolete and is not even being supported by the control system supplier; the HMI software is either no longer supported or has limited support left; the laptop computers used to maintain the new systems are already obsolete; ...
Nuclear plants face a dilemma - as technology rapidly moves forward, the licensing process continues to wallow. This creates a major vendor support and cyber security problem. If the nuclear plant licensing process makes new technology obsolete, should commercial off-the-shelf software that changes rapidly and has a limited vendor support window be allowed to be used in an environment that almost guarantees obsolescence. If not, what are the alternatives? The answer is even more important when there are safety systems involved.
Joe Weiss
