This document summarizes a research paper that investigated the performance of a ducted air conditioning system using different mass fractions of CuO nanoparticles mixed in POE oil. The researchers prepared nanofluids with 0.25%, 0.5%, 0.75%, and 1% CuO nanoparticles by mass fraction in POE oil. They tested the system performance with each nanofluid and with pure POE oil. Their results showed that adding CuO nanoparticles improved the system's coefficient of performance (COP) and decreased the compressor work compared to using pure oil. Specifically, COP increased up to 6.06 with 1% nanoparticles while compressor work decreased up to 1.027 kW. They concluded that nanofluids have the potential to enhance