Direct Expansion Ground Source Heat Pump Using Carbon Dioxide As Refrigerant

Although the detrimental environmental impacts of conventional refrigerants have raised global concern, due to the worldwide growing energy demand, high energy efficiency of heat pumps still remains a great incentive for using this technology in residential and commercial buildings. Over the last decade, several studies have been conducted to replace synthetic refrigerants with natural ones. Among the candidates, CO₂ has been attracting more attention due to being environmentally benign and safe together with superior heat transfer characteristics. This seminar presents some field operation results, modeling advancements and system and GHE performance improvements of DX-GSHP using CO₂ as refrigerant.