Trends in best-in-class energy-efficient technologies for room air conditioners

Trends in best-in-class energy-efficient technologies for room air conditioners

TitleTrends in best-in-class energy-efficient technologies for room air conditioners
Publication TypeJournal Article
Year of Publication2021
AuthorsNihar Shah, Won Young Park, Chao Ding
JournalEnergy Reports
Volume7
Pagination3162 - 3170
Date PublishedJan-11-2021
ISSN23524847
KeywordsAir-conditioner energy efficiency, best available technology, Low global warming potential (GWP) refrigerant, Market Transformation
Abstract

Improving the efficiency of room air conditioners (RACs) could provide significant energy and associated emissions savings, particularly in emerging economies with hot climates where the cooling demand is expected to increase dramatically. To help accelerate efficiency improvements, this study identifies “best-in-class” high-efficiency RAC components and products. The findings show that manufacturers tend to minimize manufacturing costs by using RAC designs that are readily available or standardized to their production, and they share components across various models. High-efficiency RAC models use advanced compressor technologies optimized at a low frequency, large heat exchangers with thermodynamically effective materials and designs, highly efficient direct current fan motors, advanced metering devices, and smart sensors for temperature and humidity control. Recently RAC manufacturers have been improving seasonal efficiency – better reflecting part-load operation – especially via variable-speed (inverter) drives for compressor motors. Recent highest-efficiency RAC models use low global warming potential (GWP) refrigerants, having transitioned from conventional high-GWP refrigerants, in regions where RACs that use these low-GWP refrigerants are commercially available. Recently demonstrated innovative technologies show trends toward smart hybrid designs, evaporative cooling, and solid-state materials beyond the conventional vapor-compression technology. This information could help policymakers improve their RAC market-transformation programs to align with the most-efficient global technology.

DOI10.1016/j.egyr.2021.05.016
Short TitleEnergy Reports