High Penetration Wireless Networking for Nuclear Power Plant Sensing

Nuclear Power Plant (NPP) operators are facing unprecedented pressure to modernize their fleets for efficiency gains and to enable the safe extension of NPP life. Although digitalization projects which deploy numerous sensors for predictive maintenance are attractive; the extreme construction standards at NPP facilities make these efforts uniquely challenging. Data wiring has been found to be the largest cost barrier when implementing facility sensor upgrades. Naturally, wireless connectivity options are therefore of interest to the industry, but the same physical impediments to running wire also present a challenging radio frequency environment.Of currently available wireless protocol options, LoRaWAN is deemed to be the best fit; this is a low- power, low-bit-rate wireless protocol with excellent signal-to-noise and extremely long range.However, a significant drawback of today’s LoRaWAN is that it is a star-topology which only supports a single wireless hop and is incapable of reliably retrieving data from inside an NPP facility. This research addresses this hurdle with a novel and cost effective all-wireless LoRa multi-hop mesh in combination with LoRaWAN, forming a hybrid interconnection architecture for NPP sensors. The mesh optimizes wireless routing in the challenging NPP environment using the next generation networking technology, Named Data Networking (NDN). NDN presents significant advantages for this challenging sensor design and enables secure and resilient communications.In our Phase I project we demonstrated a proof-of-concept lab experiment to transmit commercial sensor data end-to-end through this hybrid connection of a first hop LoRaWAN and then multiple LoRa mesh hops. In parallel, we developed technical and economic models that strongly suggests that a modest number of inexpensive mesh gateways can meet today’s sensor density expectations with margin left for future expansion.In this Phase 2 project we will implement the software in a practical form to embed the hybrid communications functionality in inexpensive commercially available gateways. Utilizing our academic and industry research partners, we will further extend the capabilities of our NDN communications platform to address this specific nuclear sensor use case. We will then evaluate a system of reasonable scale and complexity for performance and throughput. Testing will be performed both in a national laboratory and at a commercial nuclear facility.Initial commercialization discussions with our partner organizations have been extremely encouraging, particularly given the potential cost savings. This commercialization work will be further extended in Phase 2. We will also investigate the potential of extending the use cases for wireless sensors to applications currently prevented by regulatory barriers; potentially expanding the total cost savings opportunities significantly. Additionally, our partners report that next generation reactor designs have thesame problems and opportunities as today’s legacy sites, so this proposed solution will have benefits for decades to come.