NRU Reactor Diagram

AECL’s NRU reactor at Chalk River is designed to operate with eight Main Heavy Water Pumps (MHWP). The MHWPs move heavy water through the reactor to cool the fuel.  Two of the MHWPs, P-104 and P-105, are designed specifically to operate in normal, abnormal and emergency conditions. The design also includes the capability to connect P-104 and P-105 to the Emergency Power Supply (EPS).  The EPS delivers emergency back-up power to the pumps to ensure that they can continue to force coolant into the reactor vessel in the event of an external incident or power interruption.