Which strategy describes how PWRs manage their fuel over time?

Pressurized Water Reactors (PWRs) utilize a three-batch cycle system for fuel management, which is an effective strategy to maintain optimal reactor performance while allowing for the gradual replacement of fuel. In this system, the reactor core is divided into three distinct sections or "batches." Each batch is loaded with fresh fuel and remains in the reactor for a different duration.

This approach enables PWRs to achieve a steady state of fuel consumption and allows for careful monitoring of the reactor's performance over time. By using a staggered refueling schedule, the reactor continuously operates with fuel at various stages of its life cycle—fresh, partially burned, and spent—thus ensuring efficient energy production and extending the overall life of the reactor.

The benefits of this strategy include more steady power output, improved safety profiles, and enhanced economic efficiency since not all fuel is replaced at once. Additionally, it simplifies the handling and scheduling of refueling outages, reducing downtime.

In summary, the three-batch cycle system is crucial for managing fuel effectively in PWRs, balancing the need for fresh fuel with the realities of reactor operation and maintenance.