A Severe Accident is a Site-wide Event
Everyone who works in the nuclear power industry knows what happened at Fukushima in 2011. The earthquake. The tsunami. The meltdown. It was the worst nuclear disaster since Chernobyl, but it was also a wake-up call and a chance for all of us to get smarter about how we think about severe accidents and training.
A key lesson of the Fukushima incident is that severe accidents may affect more than one reactor. In fact, it may affect EVERY reactor at the site. These are complex, dangerous, and evolving multi-unit events.
Despite this, most nuclear power plant simulators are unable to simulate severe accident scenarios on more than one unit at a time. Are you basing training and analysis on a limited understanding of the true nature of catastrophic failure?
It’s time we trained for Beyond Design Basis Accidents (BDBA).
Simulating severe accidents that affect multiple units provides two advantages. First, a plant can train operators on what happens to the entire site under extreme conditions. Second, is the ability to conduct multi-unit Probabilistic Safety (PSA) and Probabilistic Risk Assessments (PRA).
Using this detailed analysis to understand an event and probable plant response, plant personnel can establish, study, and test successful mitigation strategies for any number of given scenarios.
Enhanced simulation software can help
The industry standard for severe accident analysis is EPRI’s MAAP code. The MAAP code, however, was not designed to simulate severe accident phenomena and mitigation measures for more than a single unit at a time.
Coupling multiple instances of the MAAP code with an enhanced simulation user interface can provide a real-time, interactive platform enabling unparalleled insight into severe accident progression for operators, engineers, emergency planning, and PRA/PSA teams.
Using this method, plants can perform multi-unit simulations by simultaneously running several instances of the MAAP code in an integrated and synchronized fashion, and addressing the true nature of extraordinary events, such as Fukushima.
