What the A. O. Smith HPACO-45C 1**+AXST-66CTTP 1** costs to run
At 1,341 kWh/yr, the A. O. Smith HPACO-45C 1**+AXST-66CTTP 1**'s ENERGY STAR certification puts it more expensive than most models in its category to run against every other certified electric water heater.
That $252 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 electric water heater
The category average is 1,105 kWh/yr; this model runs 21.4% above it, ranking 496 of 596 electric water heaters tracked here for running cost. That average is drawn from all 596 electric water heaters ENERGY STAR currently certifies, not an outside number, a $44/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 A. O. Smith HPACO-45C 1**+AXST-66CTTP 1**: A. O. Smith HPACO-45C 1**+AXST-66C 1** ($252/yr, 1,341 kWh/yr), then American MHPCO-45 1**+MXST-66 1** ($252/yr, 1,341 kWh/yr).
Within the A. O. Smith lineup
Ranked 45 of A. O. Smith's 61 certified electric water heaters, this sits between the HPS10-50H45DV 2** ($156/yr, the brand's cheapest) and the HPV10-80H01DV 2** ($311/yr, its priciest).
What this adds up to over time
NAHB's Study of Life Expectancy of Home Components puts a typical electric water heater's service life at 11 years; run the A. O. Smith HPACO-45C 1**+AXST-66CTTP 1** that long and it costs about $2,773 in electricity, on top of whatever it cost to buy.
Shopping for a new one
The A. O. Smith HPACO-45C 1**+AXST-66CTTP 1** runs above its category average. If the electric water heater you actually own is older still, likely well past ENERGY STAR's efficiency baseline when it was made, a current certified model could cost meaningfully less than this model's $252/year every year.
Worth comparing a few current certified models before deciding.
If you're keeping it
$252/year to run is the predictable cost of the A. O. Smith HPACO-45C 1**+AXST-66CTTP 1**; a protection plan covers the unpredictable one, a repair bill.
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. At rank 496 of 596 for running cost, see the electric water heater category page for the rest of the field, or the guide to how much your state matters.