High purity heavy water is used in PHWRs for serving as the moderator and the primary coolant. 

• The first heavy water plant was set up in India at Nangal in 1962. 
• Other Heavy water plants are at Baroda, Tuticorin, Kota, Thal, Hazira Thalchar and Manuguru. 
• The hydrogen sulphide - water process used at Kota and Manuguru plants is based on the expertise developed through indigenous R&D. 
• The technology for upgrading heavy water was developed at BARC. 
• The current research is directed towards the development of alternative, more cost-effective, technologies for heavy water production, such as hydrogen-water exchange process.

In addition to producing Heavy Water, Heavy Water Board is also engaged in following New Activities:

Production

• Production of Tri-Butyl Phosphate and D2EHPA solvents required for Solvent Extraction in Front End and Back end of Nuclear Fuel Cycle.
• Production of B¹⁰ Enriched Elemental Boron through different processes engineered by HWB, required for Prototype Fast Breeder Reactors (PFBRs) .

Developmental Work

• Based on lab technology from BARC & IGCAR, processes for commercial production of new solvents are being developed.
• Engineering & Construction of a facility to convert Uranyl Nitrate Solution to Uranium Oxide powder.
• Development of Cryogenic Process System.
• Development of process & technology for production of O18 isotope (D2O18) for PET Scanning & Metabolic Studies.
• Setting up of a R&D centre for developing NMR Solvents, Deuterium-labelled compounds and suitable catalysts for Hydrogen – Water Exchange process.
• Development of closed cell technology for Sodium Production to meet the requirement of FBRs.
• Setting up of Rare Material Recovery Plant.
• Development of technology for direct conversion of boric acid to boron carbide.