Improvement of heat pump system for space heating on the basis of exergetic analysis

Heat pump technologies for space heating play a crucial role in fight against climate change. However, their performance is generally evaluated through energy-based methods. The distinguish feature of the exergy-based approaches is that unlike to the energy-based ones they are more powerful and convenient tools for investigation and improvement of energy conversion systems without the need of additional analysis and iterations. In this paper exergy-based methods (i.e. exergy, exergeconomic and exergoenvironmental analysis) have been applied to a R134a heat pump unit for space heating. According to the results obtained, the irreversibilities occurring in the evaporator and in the condenser had to be decreased to simultaneously enhance the thermodynamic, economic and environmental performance of the investigated solution. In addition, it was found that, to achieve such a target, reducing the temperature differences through both heat exchangers was a more suitable measure compared to the replacement of the existing emission heating system.