Limerick to digitalise safety system in US 'first'

21 October 2021

A USD50 million cost-shared award from the US Department of Energy (DOE) will see Exelon Generation's Limerick plant in Pennsylvania become the first nuclear power station in the USA to upgrade to a fully digital safety system. Control room digitalisation will enable automation, decrease system interruptions, and improve performance, ultimately improving operations and significantly reducing costs.

Inside Limerick's control room (Image: @GovNuclear)

The partnership between DOE and Exelon will pave the way for modernisation of control room systems across the US nuclear fleet, Acting Assistant Secretary for Nuclear Energy Kathryn Huff said. "These upgrades will strengthen the case for extending the operation of US nuclear plants into the future, ensuring we maintain access to our nation's largest source of emissions-free electricity," she added.

Exelon will contribute USD42 million to the cost-share and has contracted Westinghouse Electric Company to replace the analogue-based reactor protection system - the plant's primary safety system - and several other systems with a single plant protection system. The main control room will be enhanced with digital displays and annunciators similar those found in Westinghouse's Generation III+ AP1000 plant.

The effort will be the first fully digital safety system modernisation using the new ISG-06 Alternate Review Process protocol, which optimises the process of licensing digital safety system upgrades, DOE said. The results will be directly applicable to other US boiling water reactors (BWRs), which make up about one-third of the country's existing nuclear fleet, and will also inform digitalisation efforts at pressurised water reactors. Advanced reactor developers will be able to apply the lessons learned to future reactor demonstrations, DOE added.

Limerick's two 1134 MWe (net) BWRs entered commercial operation in 1986 and 1990, respectively.

“While Limerick Generating Station continues to demonstrate its strong record of operational excellence, we continue to invest in upgrading the plant to ensure long-term reliability," the plant's Site Vice President Frank Sturniolo said. "Limerick is essential to providing carbon-free energy to Southeastern Pennsylvania, and these upgrades will help that effort continue for decades to come."

Researched and written by World Nuclear News