Describes a case where low-temperature phase-change materials (PCMs) were mixed with water to enhance the performance of heat transfer fluids. Adding PCM to water increases the thermal capacity of the heat transfer fluid and therefore decreases the volume that needs to be pumped. It also increases the heat transfer rate, resulting in smaller heat exchangers. Presents some results and discusses them. Notes that research is continuing in this field to determine their behaviour in large-size district cooling loops and to arrive at optimum formulations.

KEYWORDS: District cooling, heat flow, changing physical state, materials, research, laboratory testing, additives