Due to the global warming and resulting problems, attention has been paid to greenhouse gases released into the atmosphere since the 1980s and 1990s. For this reason, the Montreal Protocol and the Kyoto Protocol have tightened regulations on the use of gaseous refrigerants in both HVAC systems and industrial refrigeration. Gradually, new generations of gaseous refrigerants, that theoretically have much less negative environmental impact than their predecessors, are introduced into the market. The key parameter describing environmental impact is the GWP index, which is most often defined on a time horizon of 100 years. The long-term use of new generations of gaseous refrigerants in HVAC systems reduces CO2 emissions into the atmosphere; however, given that new generation gases often have a short lifetime, it seems that the adopted assessment may not be applicable. The aim of the article was to show how emissions of CO2 equivalent to the atmosphere differs in the short and long time horizon. The article presents the results of calculations of equivalent CO2 emissions to the atmosphere caused by the operation of compressor cooling devices used in HVAC systems, where cooling is done with the use of water or a water-glycol solution. The analysis was carried out for 28 commonly used devices on the world market. The analyzed devices work with refrigerants: R513A, R454B, R290, R1234ze, R32, R134a, R410A. The equivalent emissions values for GWP 100 and GWP 20 were analyzed in relation to the unit power of the devices depends on refrigerant mass and number of fans. The study showed that in the case of new generation refrigerants with a very short lifetime, the use of GWP 100 indicators is misleading and does not fully reflect the effects of environmental impact, especially in the area of refrigeration equipment application. The article shows that the unit value of the cooling load related to the number of fans or the unit would be helpful in assessing the environmental impact of a cooling device.

The article summarizes the results of the 25-year time horizon performance analysis of the ground source heat pump that serves as a heat source in a detached house in the climatic conditions that prevail in Wrocław, Poland. The main aim is to assess the potential of ground regeneration and reduction of CO2 emission by passive cooling application. The study adds value to similar research conducted worldwide for various conditions. The behavior of the lower source of the heat pump was simulated using EED software. The ground and borehole properties, heat pump characteristics, heating and cooling load, as well as the energy demand for domestic hot water preparation have been used as input data. Based on the brine temperatures for all analyzed cases including the ground with lower and higher values of conductivity and heat capacity, the borehole filler of inferior and superior thermal properties, and the passive cooling option turned on and off, the seasonal efficiencies of the heat pump have been calculated. The energy and emission savings calculations are based on the values obtained. The application of passive cooling reduces the brine temperature drop by 0.5 K to over 1.0 K in consecutive years in the analyzed cases and the thermal imbalance by 65.0% to 65.9%. Electric energy savings for heating and domestic hot water preparation reach 4.5%, but the greatest advantage of the system is the possibility of almost emission-free colling the living spaces which allows reducing around 33.7 GWh of electric energy and 1186–1830 kg of CO2 emission for cooling.