IPHWR-700


The IPHWR-700 is an Indian pressurized heavy-water reactor designed by Bhabha Atomic Research Centre. It is a Generation III+ reactor developed from earlier 220 MW and 540 MW designs and can generate 700 MW of electricity. Currently there are 6 units under construction and 10 more units planned at a cost of INR 1.05 trillion

Development

The PHWR technology was introduced in India in the late 1960s with the construction of RAPS-1 CANDU reactor in Rajasthan. All the main components for first unit were supplied by Canada while India did the construction, installation and commissioning job. In 1974 after India conducted Smiling Buddha, its first nuclear weapons test Canada stopped their support of the project, delaying the commissioning of RAPS-2 until 1981.
After Canadian withdrawal from project, research, design and development work in Bhabha Atomic Research Centre and Nuclear Power Corporation of India along with some industry partners who did the manufacturing and construction work enabled India in establishing this technology in totality. Over four decades, 15 220 MW reactors of indigenous design were built. Improvements were made in the original CANDU design to reduce construction time and cost, new safety systems were incorporated and thus reliability was enhanced leading to better capacity factors. Realising the economics of scale, a 540 MW design was developed by NPCIL. 2 units of this design were constructed at the Tarapur Atomic Power Station. Further optimisations were carried out to utilise the excess thermal margins and the 540 MW PHWR design was modified to that of 700 MW capacity without much design changes. Almost 100% of the components of these indigenously designed reactors are manufactured by the Indian industry.

Design

Like other pressurized heavy-water reactors, IPHWR-700 uses heavy water as its coolant and neutron moderator. The design retains the features of standardized Indian PHWR units, which include:
It also includes some new features as well. These include:
The reactor has very less excess reactivity because of which it does not need neutron poison inside the fuel or moderator. These provisions are made in design to handle the case of a loss of coolant accident which caused Fukushima Daiichi nuclear disaster.

Operation

The reactor uses 0.7% enriched uranium with Zircaloy-4 cladding as fuel. The core produces 2166 MW of heat which is converted into 700 MW of electricity at an efficiency of 32%. Because of lack of excess reactivity inside the reactor, it needs to be refuelled continuously during operation. The reactor is designed for an estimated life of 60 years.

Reactor fleet

Power stationOperatorStateUnitsTotal capacity
Mahi BanswaraNPCILRajasthan700 x 42,800
KaigaNPCILKarnataka700 x 21,400
ChutkaNPCILMadhya Pradesh700 x 21,400
GorakhpurNPCILHaryana700 x 21,400