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The cooling of equipment and products is an integral part of many manufacturing processes. This paper describes typical process cooling systems used in manufacturing and the approximate cost of cooling for each system. The paper then describes the inside out approach to energy efficiency, which recommends sequential evaluation of end use, distribution and primary energy conversion systems, as it relates to process cooling. General methods for improving the energy efficiency of cooling processes, organized according to the inside-out approach, are described. These methods include adding insulation and heat exchangers, improving process control, avoiding mixing, employing variable-speed and low friction pumping systems, and using cooling towers in place of chillers. The fundamental equations for estimating savings, and examples, are presented for these methods.

Open tanks and exterior surfaces of process heating equipment lose heat to the surroundings via convection, radiation, and/or evaporation. A practical way of reducing heat loss is by insulating or covering the surfaces. This paper presents methods to quantify heat loss and energy savings from insulating hot surfaces and open tanks. The methods include radiation and evaporation losses, which are ignored by simplified methods. In addition, thermal mass, such as refractory, conveyor and racking equipment, acts as a heat sink and increases heating energy use in process heating applications. This paper presents lumped capacitance and finite-difference methods for estimating heat loss to thermal mass, and savings from reducing this loss. The methods described above have been incorporated in free software, and are demonstrated using case study examples. The examples demonstrate the magnitude of the potential error from using simplified methods.