Caliskan, OguzErsoy, H. Kursad2026-03-102026-03-1020252149-21232148-4171https://doi.org/10.17350/HJSE19030000365https://search.trdizin.gov.tr/en/yayin/detay/1383190/comparative-energetic-and-environmental-investigation-of-air-to-air-heat-pump-cycles-using-ultra-low-gwp-refrigerantshttps://hdl.handle.net/20.500.13091/13093Global warming has become a worldwide problem in recent years, and authorities are taking action to overcome this problem. Refrigerants with high global warming potential (GWP) are continuously prohibited, and as a result, ultra-low GWP refrigerants stand out in the heating, cooling, refrigeration, and air conditioning (HVAC-R) industry. This paper presents a theoretical analysis of air-to-air heat pump cycles using 2024 F-Gas regulation-compliant ultra-low GWP refrigerants, including hydrocarbons and transcritical CO2, with three different configurations. Annual energy consumption and total equivalent warming impact (TEWI) values were calculated for three provinces in Türkiye with different climates using bin-hour data. The results were compared in both cooling and heating modes with R410A and R32 cycles as well. Up to 11.7% and 14.5% improvement in annual energy consumption was achieved using parallel compression and booster cycle, respectively. Cycles with booster configuration using R290 and R600a refrigerants achieved the best performance.eninfo:eu-repo/semantics/openAccessMühendislikMakineYeşilSürdürülebilir Bilim ve TeknolojiEnerji ve YakıtlarArticle10.17350/HJSE19030000365