https://www.cnet.com/news/carriers-smart-air-conditioner-keeps-you-cool-at-ces-2018/ >Carrier is back at CES, but this year it's all about air conditioners -- specifically its new 9,000 BTUh single zone ductless system. Yes, I know it's winter in many parts of the world right now, but this snazzy system is making some pretty big claims about its cooling capabilities.  >First up? Its energy rating. Carrier says its latest cooling appliance is the "most efficient" you can get in North America because of its "42 SEER" rating. A search on the U.S. Department of Energy site directed me to this piece of information: "Central air conditioners are rated according to their seasonal energy efficiency ratio (SEER). SEER indicates the relative amount of energy needed to provide a specific cooling output. Many older systems have SEER ratings of 6 or less."