What the Seasons ST12VB2 costs to run
The Seasons ST12VB2 is certified by ENERGY STAR at 647.5 kWh a year, about average for its category to run among room air conditioners currently certified.
That $122 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
The category average is 603 kWh/yr; this model runs 7.4% above it, ranking 340 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 Seasons ST12VB2: Seasons ST12VB1 ($122/yr, 647.5 kWh/yr), then Friedrich KCVM14B10B ($123/yr, 652.8 kWh/yr).
Same brand, different models
Ranked 7 of Seasons's 10 certified room air conditioners, this sits between the SW06VB1 ($62/yr, the brand's cheapest) and the SW24V2 ($245/yr, its priciest).
Seasons ST12VB2 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 Seasons ST12VB2 that long and it costs about $1,217 in electricity, on top of whatever it cost to buy.
Weighing a replacement
Efficient as certified room air conditioners go, $122/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
$122/year to run is the predictable cost of the Seasons ST12VB2; a protection plan covers the unpredictable one, a repair bill.
Where this number comes from
Nothing here is estimated from a nameplate wattage; the 647.5 kWh/yr is ENERGY STAR's own certified figure for this model. Ranked 340 of 447, the Seasons ST12VB2 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.