RE:MOF technology will make deuterium cheaperThe big advantage of using heavy water is that you do not need to enrich the Uranium fuel used in the reactor. There are only two reactor designs that can operate on natural (ie non-enriched) uranium and those are the UK designed Magnox gas-cooled reactors (I used to operate one of those plants) and the Canadian designed CANDU reactor which stands for CANada Dueterium Uranium. It is the latter design that uses Heavy Water. Because Canada does not have an enrichment plant and is a signatory to the non-proliferation treaty there is no capability to make fuel for PWR or BWR reactors that must have enriched fuel to operate -usually in the range 3 to 5%. The USA and Russia favoured the PWR design since they already had a weapons program and the enrichment plants that are required for that - so it made perfect sense for them. It ALSO means from a political standpoint that if you are a nation with NO enrichment facilities then you are 100% dependent upon the supplying countries for your enrichment services and by default your electricity supply....not a very good position to be in I would say.
So in short the only reactor that operates using heavy water is the CANDU reactor.
and that will be the case for many years as there are no new designs in the offing.
Malcolm