Resumen de Comparative Exergy Analysis of Heat Pumps for Heat Recovery Applications
Heat pumps have a multitude of applications and therefore there are many types of heat pumps. In one peculiar application heat pumps proved to be very effective, for low grade waste heat recovery. Several criteria can be considered for choosing a heat pump, such as application scope, coefficient of performance, etc. Sometimes these criteria are not enough, and some more must be found. The paper suggests the use of comparative exergy analysis in order to choose the heat pump that best suits the application for which is intended. Exergy analysis is a powerful tool that allows us to analyze in detail the processes that are taking place in a heat pump, enabling us to choose knowingly between different types of heat pumps the one that best suits our application. Two new criteria for choosing a heat pump are suggested: cycle compression work and environmental impact of the refrigerant. Exergy analysis shows that the choice of the vapour compression heat pump, purely from COP point of view is legitimate, but the choice of the gas pump can be rightful due to smaller cycle compression work and refrigerant used, which in case of gas compression heat pump is air, neutral in terms of environmental impact.
