Pressurised heavy water reactor
Also called: PHWR · Topic: Energy Resources of India: Conventional and Non-conventional · NCERT: Beyond NCERT
Meaning
A pressurised heavy water reactor (PHWR) is a nuclear reactor that burns natural uranium as its fuel. Natural uranium means uranium that has not been enriched. The reactor uses heavy water, a form of water with a heavier kind of hydrogen. The heavy water slows down the reaction so that it keeps going, and it also carries heat away from the core. That heat makes steam, and the steam turns turbines. PHWRs make up Stage 1 of India's three-stage nuclear power programme. India has little uranium and cannot easily enrich it, so a reactor that runs on natural uranium suits the country.
Example
India's first home-designed 700 MWe PHWR units started running at Kakrapar, Gujarat, in 2023. India's Bharat Small Reactors are being designed from its older 220 MWe PHWR.
Don't confuse with
- Boiling water reactor: uses ordinary water and enriched uranium. Tarapur, India's first nuclear station (1969), used US-built boiling water reactors.
- Fast breeder reactor: Stage 2 of the programme. It runs on plutonium and is cooled by sodium, like the Prototype Fast Breeder Reactor at Kalpakkam.
Related concepts
- Nuclear energy
- Uranium
- Thorium
- Bhabha Atomic Research Centre
- Tarapur Atomic Power Station
- Kudankulam Nuclear Power Plant
- Jaitapur nuclear project
- Three-stage nuclear power programme
- Prototype Fast Breeder Reactor
- Small modular reactor