Using Carbon Dioxide (R-744) refrigerant results in what kind of efficiency?

Using Carbon Dioxide (R-744) as a refrigerant generally results in much lower efficiency compared to conventional refrigerants like HFCs or HCFCs, particularly in typical HVAC applications. R-744 operates at high pressures and has distinct thermodynamic properties compared to more common refrigerants.

While R-744 has some advantages, such as being environmentally friendly and having a low global warming potential, it often cannot achieve the same level of energy efficiency as other refrigerants. In many cases, systems utilizing R-744 require more energy to operate effectively due to its operating characteristics, such as lower heat transfer capabilities in certain conditions. Therefore, its overall efficiency is typically deemed to be lower in practical applications relative to other refrigerants.