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Fusion Science and Technology
Penfield and Enos: Outage planning in the COVID-19 era
Energy Harbor’s Beaver Valley plant, located about 34 miles northwest of Pittsburgh, Pa., was one of many nuclear sites preparing for a scheduled outage as the coronavirus pandemic intensified in March. The baseline objective of any planned outage—to complete refueling on time and get back to producing power—was complicated by the need to prevent the transmission of COVID-19.
While over 200 of the plant’s 850 staff members worked from home to support the outage, about 800 contractors were brought in for jobs that could only be done on-site. Nuclear News Staff Writer Susan Gallier talked with Beaver Valley Site Vice President Rod Penfield and General Plant Manager Matt Enos about the planning and communication required.
Beaver Valley can look forward to several more outages in the future, now that plans to shut down the two Westinghouse pressurized water reactors, each rated at about 960 MWe, were reversed in March. “The deactivation announcement happened in the middle of all our planning,” Enos said. “It’s a shame we haven’t had a chance to get together as a large group and celebrate that yet.”
While the focus remains on safe pandemic operations, the site now has two causes for celebration: an outage success and a long future ahead.
Tonio Pinna, Fabio Borgognoni
Fusion Science and Technology | Volume 67 | Number 3 | April 2015 | Pages 531-534
Proceedings of TRITIUM 2013 | dx.doi.org/10.13182/FST14-T72
Articles are hosted by Taylor and Francis Online.
Two of the key elements of the engineering development of the DEMO reactor are the definitions of reliability and availability requirements (or targets). The availability target for a hypothesized Fuel Cycle has been analysed as a test case. The analysis has been done on the basis of the experience gained in operating existing tokamak fusion reactors and developing the ITER design. Plant Breakdown Structure (PBS) and Functional Breakdown Structure (FBS) related to the DEMO Fuel Cycle and correlations between PBS and FBS have been identified. At first, a set of availability targets has been allocated to the various systems on the basis of their operating, protection and safety functions. 75% and 85% of availability has been allocated to the operating functions of fuelling system and tritium plant respectively. 99% of availability has been allocated to the overall systems in executing their safety functions. The chances of the systems to achieve the allocated targets have then been investigated through a Failure Mode and Effect Analysis and Reliability Block Diagram analysis. The following results have been obtained: i) the target of 75% for the operations of the fuelling system looks reasonable, while the target of 85% for the operations of the whole tritium plant should be reduced to 80%, even though all the tritium plant systems can individually reach quite high availability targets, over 90% - 95%; ii) all the DEMO Fuel Cycle systems can reach the target of 99% in accomplishing their safety functions.