Nuclear power plants

Nuclear power plants (NPPs) generate electricity from nuclear power obtained through a nuclear fission chain reaction inside the vessel of a nuclear reactor that contains the nuclear fuel. This chain reaction is controlled by different systems to produce the desired amount of energy. Most of the nuclear power plants use Uranium (U-235) or Plutonium (Pu-239) as nuclear fuel. Nuclear power plants can produce electricity ranging from 100 Mega Watt to One Giga Watt.

There are different types of nuclear reactors in the world; Pressurized Water Reactor (PWR), Boiling Water Reactor (BWR), Pressurized Heavy water Reactor (PHWR), Advanced gas-cooled reactor (AGR), Light water Graphite-moderated Reactor (LWGR) etc. Most of the NPPs are designed to have lifetime of 40~60 years.

NPPs in Pakistan are owned and operated by PAEC. Currently, Pakistan has only two sites where NPPs are situated i.e. Chashma site and Karachi site. At Chashma site, there are four 2-loop PWRs of approx 300 MWe whereas Karachi site has one small 137 MWe Candu Pressurized Heavy water Reactor (PHWR) and two 3-loop PWRs of 1100 MWe each.

These NPPs submit different licensing and routine submissions to PNRA as per applicable regulations which provides technical information and data about activities related to nuclear safety, radiation safety and exposure of workers. PNRA performs review & assessment of these submissions to ensure safe operation of the plants and various authorizations are issued to licensees during different stages of nuclear installations.

PNRA has also established Regional Nuclear Safety Directorates at Kundian and Karachi for the conduct of regulatory inspections at site NPPs. Inspections are conducted during all phases of a nuclear installation’s life cycle, i.e. construction, installation, commissioning, operation, etc. PNRA continuously monitors the construction activities including manufacturing of safety class equipment of the plants. PNRA’s resident inspectors undertake different routine and planned inspections at NPPs according to their annual inspection plan. Unplanned and reactive inspections are carried out as and when required. Subsequently, PNRA issues inspection reports including directives to communicate the deficiencies observed during inspections to the licensees in the form of inspection reports along with necessary requirements for taking corrective actions. A follow-up process is in place to ensure satisfactory implementation of corrective actions. The departments at PNRA Headquarters also provide technical support during the regulatory inspections to the regional directorate(s), whenever needed.

 Chashma Nuclear Power Plant Unit-1 (C-1)

C-1 is a two loop Pressurized Water Reactor (PWR) having generation capacity of 325 MWe. The plant is in operation since year 2000. The first Operating License (OL) to C-1 was issued in October 2004. As per PNRA Regulations PAK/909, C-1 OL was revalidated after first Periodic Safety Review (PSR) in December 2010 with validity till December 2020. Subsequently, C-1 OL is revalidated for second time after second PSR in December 2020 which is valid till December 2030.

 Chashma Nuclear Power Plant Unit-2 (C-2)

C-2 is a two loop Pressurized Water Reactor (PWR) having generation capacity of 340 MWe and is in operation since 2011. C-2 is an improved version of C-1 with certain safety enhancements. The Operating License (OL) to C-2 was issued in February 2012 which is valid till December 2021.

 Chashma Nuclear Power Plant Unit-3 (C-3)

C-3 is a two-loop Pressurized Water Reactor (PWR) having generation capacity of 340 MWe and is in operation since 2016. C-3 is an improved version of C-2 and C-1 plants by incorporating experience feedback. The Operating License (OL) to C-3 was issued in May 2018 which is valid till December 2026.

 Chashma Nuclear Power Plant Unit-4 (C-4)

C-4 is a two-loop Pressurized Water Reactor (PWR) having generation capacity of 340MWe and is in operation since 2017. C-4 is an improved version of C-2 and C-1 plants by incorporating experience feedback. The Operating License (OL) to C-4 was issued in May 2018 which is valid till December 2027.

 Karachi Nuclear Power Plant Unit-1 (K-1)

Karachi Nuclear Power Plant Unit-1 (K-1) is a 137 MWe CANDU type pressurized heavy water reactor. The plant has completed its 30 years of design life in 2002 and is operating beyond its design life since 2003. As per PNRA Regulations and periodic safety review outcome, a lot of design changes/improvements have been made and hence K-1 Operating License was extended after satisfactory review of these changes alongwith other licensing submissions. K-1 will be the first nuclear power plant of Pakistan which will undergo decommissioning in 2021 (tentatively). Deferred dismantling strategy has been selected for decommissioning of K-1.

 Karachi Nuclear Power Plants Unit-2 and Unit-3 (K-2/K-3)

K-2 and K-3 are three loop pressurized light water reactors (Gen-III Plants) having generation capacity of 1100 MWe are under construction at Karachi. Construction licenses to K-2 and K-3 were issued in 2015 and all the construction activities at K-2 and K-3 are being performed safely under the regulatory oversight of PNRA. PNRA granted permission for commissioning to K-2/K-3 on September 17, 2019. Furthermore, permission to introduce nuclear material into the core of K-2 was granted by PNRA on November 28, 2020.