The Indian regulator has given the go-ahead for the 700 MWe pressurised heavy water reactor to move to the next stage of commissioning and increase power to 50%. The unit reached first criticality in December.

The Kakrapar site is also home to two operating 202 MWe PWHR, seen here on the right (Image: DAE GODL-India)

"The Atomic Energy Regulatory Board (AERB) issued Permission for the Phase-C Commissioning stage of Kakrapar Atomic Power Project Unit-4 (KAPP-4) on February 09, 2024, after a satisfactory Safety Review," the Atomic Energy Regulatory Board said. The permit is valid until 30 June.

Phase-C commissioning will see the power of the reactor gradually increased in three stages as the reactor undergoes testing. The first stage - C-1 - allows the unit to increase power to 50%. Phase C-2 will allow the power to be increased to 90%. The final stage will allow the power to be increased to 100%. Regulatory permission will be required to move from one stage to the next.

KAPP 4 is an Indian-designed and built 700 MWe pressurised heavy water reactor and is the second in a series of sixteen units such units, the first of which - Kakrapar unit 3 - was declared in commercial operation in mid-2023.