TCL T12WV4S: running cost
The TCL T12WV4S is certified by ENERGY STAR at 562.5 kWh a year, about average for its category to run among room air conditioners currently certified.
That $106 is priced at 18.8¢/kWh, the average of all 51 state rates this site tracks. Your own state's rate is one click away.
Efficient, or not, for a room air conditioner
Against the category average of 603 kWh/yr, this model uses 6.7% less, ranking 241 of 447 room air conditioners tracked here for running cost. That average is drawn from all 447 room air conditioners ENERGY STAR currently certifies, not an outside number, a $8/year gap from this model at the national rate. Full sourcing is in the sourcing notes.
Right next to it on the list
A rank or two either side of the TCL T12WV4S: Midea MWFUWA-12CRFN8-BCP0 ($106/yr, 562.5 kWh/yr), then TCL T12WV9S ($106/yr, 562.5 kWh/yr).
Same brand, different models
Ranked 35 of TCL's 59 certified room air conditioners, this sits between the T05WV9M ($51/yr, the brand's cheapest) and the T24WQ2S ($266/yr, its priciest).
TCL T12WV4S over 10 years
NAHB's Study of Life Expectancy of Home Components puts a typical room air conditioner's service life at 10 years; run the TCL T12WV4S that long and it costs about $1,058 in electricity, on top of whatever it cost to buy.
Weighing a replacement
Efficient as certified room air conditioners go, $106/year is a reasonable baseline if you're comparing what else is on the market.
Worth comparing a few current certified models before deciding.
If you're keeping it
Whether or not the TCL T12WV4S ever needs replacing, a repair is the more common failure for a room air conditioner, one a protection plan budgets for ahead of time.
Where this number comes from
Two sourced numbers, nothing modeled: ENERGY STAR's certified kWh/yr for this exact model, and EIA's published state electricity rate. Ranked 241 of 447, the TCL T12WV4S sits in the middle of the room air conditioner category, see the guide to why your state changes this number for the other half of the math.