What does HWR stand for?

Heavy Water Reactor

A pressurized heavy-water reactor is a nuclear power reactor, commonly using unenriched natural uranium as its fuel, that uses heavy water (deuterium oxide D2O) as its coolant and moderator. The heavy water coolant is kept under pressure, allowing it to be heated to higher temperatures without boiling, much as in a Pressurized water reactor. While heavy water is significantly more expensive than ordinary light water, it creates greatly enhanced neutron economy, allowing the reactor to operate without fuel-enrichment facilities (lowering the additional expense of the heavy water) and enhancing the ability of the reactor to make use of alternate fuel cycles.

Healthy weight range

Heavy Water Reactors