Energy performance analysis of a cascade heat pump system for heating in a semiconductor fabrication plant

Abstract

To reduce carbon emissions, active research is being conducted on replacing the heating equipment using fossil fuels with heat pumps. While heat pumps still utilize electricity and have associated carbon emissions, they possess the potential to consistently decrease carbon emissions owing to the growing availability of renewable energy sources.In this study, the applicability of a heat pump system capable of supplying 86 °C hot water for heating a semiconductor fabrication plant was verified. In addition, there are a few results considering the energy saving effect that can be obtained from the heat source. Therefore, reflecting the characteristics of a semiconductor fabrication plant, which requires a huge cooling load to remove heat from equipment even in winters, a cascade heat pump system using a chiller as a low-cycle heat pump was proposed. Compared to a boiler, the heat pump system has the advantage of reducing the load on the typical chiller system as it can supply cold and hot water.On comparison, the cascade heat pump system, which incorporates the energy-saving effect derived from the heat source, demonstrated 66 % of primary energy and 56 % carbon emissions than the boiler. Consequently, the cascade heat pump outperformed the boiler system.

Keywords

• Semiconductor fabrication plant
• Cascade cycle
• Centrifugal heat pump
• Outdoor air-conditioner
• Heating equipment