What the A. O. Smith CAHP-40 2** costs to run
At 902 kWh/yr, the A. O. Smith CAHP-40 2**'s ENERGY STAR certification puts it cheaper than most models in its category to run against every other certified electric water heater.
The $170 figure above uses the simple average of all 51 published state rates. Pick your state for the real number.
A. O. Smith CAHP-40 2** against the category
That's 18.4% below the electric water heater category average of 1,105 kWh/yr, and ranks 154 of 596 certified electric water heaters for annual running cost, 1 being cheapest. The category average comes from every electric water heater ENERGY STAR currently certifies (596 models), not an outside benchmark, about $38/year below that average at the national rate. See the methodology page.
What sits beside it in the ranking
A. O. Smith HP1050H45DV 1** ($170/yr, 902 kWh/yr) costs a little more to run than the A. O. Smith CAHP-40 2**. Ruud PROUH65 T2 RU350UM ($169/yr, 900 kWh/yr) costs a little less.
Same brand, different models
A. O. Smith makes 61 ENERGY STAR certified electric water heaters; this one ranks 7 of 61 for running cost, between the brand's cheapest, the HPS10-50H45DV 2** at $156/yr, and its priciest, the HPV10-80H01DV 2** at $311/yr.
A. O. Smith CAHP-40 2** over 11 years
11 years is NAHB's typical service life for this category; at $170/year, the A. O. Smith CAHP-40 2** adds up to about $1,865 in electricity over that span.
Is it worth replacing?
The A. O. Smith CAHP-40 2** is already efficient for its category at $170/year. If you're shopping and comparing options, this is roughly what a well-chosen new electric water heater costs to run.
Compare current ENERGY STAR certified electric water heaters before buying.
Protecting what you have
The A. O. Smith CAHP-40 2** already costs $170/year to run; a repair bill on top of that is the kind of expense a protection plan exists to smooth out.
Sourcing
Ranked 154 of 596, the A. O. Smith CAHP-40 2** sits in the middle of the electric water heater category, see the guide to why your state changes this number for the other half of the math. The 902 kWh/yr figure is ENERGY STAR's own certification, not a wattage estimate; exact dataset IDs are on the data sources page.