Investigations of life cycle climate performance and material life cycle assessment of packaged air conditioners for residential application

A comprehensive investigation for life cycle climate performance (LCCP) and material life cycle assessment (LCA) is performed under various influencing factors for the packaged conditioners. The whole carbon dioxide equivalent (CO2-eq.) emissions during an air conditioner's lifetime are evaluated from the LCCP aspect. Results indicate that the seasonal energy efficiency ratio (SEER) rating has a large influence on the emission variation, 13 SEER R410A has approximately a +3% CO2-eq. emission increase when compared with the 13 SEER R22 in the area of Richmond, which is mainly caused by the direct emission of annual leakage of high GWP R410A. The efficient 14 SEER R410A unit depicts a 9% reduction. In general, as the climate is varied from cold to hot, the emissions are increased. Among the emission contributors, the energy consumption accounts for more than 70% of the total emissions, followed by annual refrigerant leakage. Parameter analysis reveals that the refrigerant recovery rate has a larger effect on the LCCP results than the cycle degradation coefficient, especially in the cold areas. In addition, the two capacity air conditioner product has approximately a 13% emission reduction due to the better load matching. Material LCA investigation shows that, in general, most of the material phase environmental performance is decreased in 14 SEER air conditioners. This is because the addition of aluminum from employing of the micro-channel heat exchanger. For a sustainable future, minimizing material use and CO2-eq. emissions and maximizing energy efficiency should have been considered in its entirety.