Water-cooled reactors

More water-cooled reactors are being built than any other type in the world today. They include boiling-water and pressurised-water systems, moderated and cooled by ordinary water, and the Canadian CANDU reactor, in which heavy water is used as moderator and coolant. Now being commissioned, the British steam-generating heavy-water reactor combines features from many earlier types, and is expected to prove of worldwide interest.