Alternate Rod Worth Verification Delivers Short-Term Savings with Long-Term Opportunities

Startup program reduced schedule time and cost while enabling future operational flexibility.

The Challenge
A U.S. utility was in need of a solution to help them optimize their low power physics testing (LPPT). As LPPT is typically performed on outage critical path, it necessitates several secondary tasks, special test equipment and administrative controls. Improving schedule and resource costs associated with LPPT will help plants realize significant savings. The utility looked to Westinghouse to provide a robust, alternative core design validation method for reload cycles that minimized critical path time and risk associated with plant startup.

Our Solution
Westinghouse delivered its Alternate Rod Worth Verification (ARWV) methodology. Designed to be applied at most PWR units, pending review of the current licensing basis and startup test program requirements., ARWV offers multiple paths to eliminate rod worth that best suit the utility needs, reducing schedule time and cost. The ARWV program can also enable self-performance of nuclear design scope and supplemental data collection associated with the ARWV program requirements, which can result in additional cost savings.

For this project, Westinghouse implemented a conditional rod worth elimination approach at PWR units across the utility’s multiple stations that accommodated wide variations in future core loading pattern design. To meet both the customer’s short and long-term needs, Westinghouse strategically designed the ARWV applicability requirements to consider varying cycle lengths, types of fuel, burnable absorbers and rod cluster control assemblies.

The Impact
Beyond the cost and schedule benefits realized with the elimination of rod worth measurements, the ARWV program streamlined the activities between hot standby and power operation conditions by eliminating infrequently performed plant maneuvers and all ancillary aspects of traditional LPPT. The re-designed startup test program seamlessly blended with routine outage activities and greatly reduced the probability of a reactor trip, human performance event or reactivity management issue.