Once-Through Cooling is a heat-rejection method that draws water from a source such as a river, lake or sea, passes it through heat exchangers once, and returns it warmer, without evaporative loss. It avoids the consumptive water use of cooling towers but requires abundant water, raises the return temperature of the source, and faces environmental permitting constraints. Some water-adjacent data centers use it for efficient, low-consumption cooling.
Category: Sustainability & Metrics · Subcategory: Water & Heat Reuse · Part of the AIDC Technical Terminology reference.