I ran a rather terrifying experiment this month. I, along with my wife, live in a fairly new (~eight-year-old) building. My LDK and office are on my second floor (first is ground floor to me) with some sliding doors to separate them (which are open unless I’m in a meeting). My LDK and office both have an aircon unit. I rarely use the one in my office. My LDK aircon has been on “dry” with the occasional stint on ~22 degrees when it’s really hot for a bit. I use the one in my office only when I’m super hot and only for as little as possible.

We also have an aircon on our first (ground) floor in the bedroom. I start it at ~21 most nights and switch to “dry” after an hour. I was dreading our electric bill, but it just came today. From 6/18 to 7/17, we (2 people in 40-amp type A service) used 504 kWh and had a bill of just over 1万4千円.

I was honestly dreading the bill because some aircon units are really bad on a dry setting, but ours were good. I hope you all are staying cool enough in this weather. I thought I’d share in case the data point helps people.

EDIT: 2LDK + Loft, ~54m^2 plus whatever the loft is