SGHWR

Steam Generating Heavy Water Reactor (SGHWR) is a pressure tube type, heavy water moderated, light water cooled nuclear reactor. The steam generating heavy water reactor is in principle the same as a BWR but relies on a special heavy water material as the moderator whilst using conventional water as the primary coolant. They are similar in design to the CANDU, which uses pressure tubes and separates the coolant and moderator - the Gentilly-1 CANDU-BWR prototype was in fact a reactor of this type.
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