WattCost

Data through April 2026

Running cost · Water Heaters (Electric) · ENERGY STAR certified

A. O. Smith HPACO-45C 1**+AXST-50SC 1

Heating a typical household's hot water, the A. O. Smith HPACO-45C 1**+AXST-50SC 1 is certified at 923 kWh a year — about $174 at the U.S. average electricity rate, or $14.48 a month. Efficiency-wise it's unremarkable in a good way: within 15% of the median certified electric water heater (rank 214 of 566). Where you live moves the bill from $114 a year in North Dakota to $430 in Hawaii.

Estimated annual running cost · U.S. average rate 18.8¢/kWh

$174/yr

$121 · cheapest certified water heaters (electric)$328 · priciest
Per month
$14.48
Per day
48¢
Certified use
923 kWh/yr
Type
Hybrid/Electric Heat Pump
Heat pump type
Split System HPWH
Storage volume
46 gal
First-hour rating
70 gal
UEF
3.52
643 kWh1,741 kWh
Where the A. O. Smith HPACO-45C 1**+AXST-50SC 1 (▮) sits among all 566 certified water heaters (electric), by annual kWh

What it costs in every state

A. O. Smith HPACO-45C 1**+AXST-50SC 1: 923 kWh/yr × each state's average residential rate (EIA)
StateRate ¢/kWhThis model $/yrRelative cost
Alabama17.4¢$161
Alaska27.4¢$252
Arizona15.5¢$143
Arkansas14.2¢$131
California35.3¢$325
Colorado16.5¢$153
Connecticut32.2¢$298
Delaware18.8¢$173
District of Columbia25.4¢$235
Florida15.4¢$142
Georgia15.4¢$142
Hawaiipriciest46.6¢$430
Idaho12.7¢$117
Illinois20.5¢$189
Indiana17.9¢$165
Iowa13.9¢$128
Kansas15.8¢$146
Kentucky15.0¢$139
Louisiana14.4¢$133
Maine28.4¢$262
Maryland22.1¢$204
Massachusetts29.4¢$272
Michigan21.4¢$197
Minnesota16.4¢$151
Mississippi16.8¢$155
Missouri14.0¢$129
Montana13.9¢$128
Nebraska13.3¢$123
Nevada14.3¢$132
New Hampshire27.2¢$251
New Jersey23.5¢$217
New Mexico15.2¢$140
New York29.4¢$272
North Carolina16.3¢$150
North Dakotacheapest12.3¢$114
Ohio19.5¢$180
Oklahoma13.3¢$123
Oregon15.8¢$146
Pennsylvania21.5¢$198
Rhode Island28.3¢$261
South Carolina17.1¢$157
South Dakota14.5¢$134
Tennessee14.9¢$138
Texas17.0¢$157
Utah13.3¢$123
Vermont24.6¢$227
Virginia17.4¢$160
Washington14.4¢$133
West Virginia16.1¢$148
Wisconsin19.2¢$177
Wyoming14.7¢$135

Certified models closest in efficiency

electric water heaters within reach of 923 kWh/yr
ModelkWh/yr$/yr (US avg)
A. O. Smith HPACO-45 1**+AXST-50S 1923$174
A. O. Smith HPACO-45 1**+AXST-50STTP 1923$174
A. O. Smith HPACO-45 1**+AXST-50T 1923$174
A. O. Smith HPACO-45 1**+AXST-50TTTP 1923$174
A. O. Smith HPACO-45C 1**+AXST-50SCTTP 1923$174
A. O. Smith HPACO-45C 1**+AXST-50TC 1923$174

Run your own numbers

Your rate, your numbers

Per day
48¢
Per month
$14.48
Per year
$174

923 kWh/yr × 18.8¢/kWh = $174/yr

Prefilled with this model's certified 923 kWh/yr — adjust if your usage differs from the DOE test basis. The certified annual kWh comes from the DOE Uniform Energy Factor test, which simulates a typical household's daily hot-water draw pattern. Only electric models (including heat-pump units) are listed — gas models burn gas, not kWh.

Questions, answered with the data

How much electricity does the A. O. Smith HPACO-45C 1**+AXST-50SC 1 use?
ENERGY STAR certifies the A. O. Smith HPACO-45C 1**+AXST-50SC 1 at 923 kWh per year. The certified annual kWh comes from the DOE Uniform Energy Factor test, which simulates a typical household's daily hot-water draw pattern. Only electric models (including heat-pump units) are listed — gas models burn gas, not kWh.
How much does the A. O. Smith HPACO-45C 1**+AXST-50SC 1 cost to run per month?
About $14.48 a month at the U.S. average residential rate (18.8¢/kWh) — 48¢ a day, or $174 a year. Your state's rate moves this up or down; see the table above.
Is the A. O. Smith HPACO-45C 1**+AXST-50SC 1 energy efficient?
It uses 15% less electricity than the median certified electric water heater.
What does the A. O. Smith HPACO-45C 1**+AXST-50SC 1 cost to run in the cheapest vs. priciest state?
At current residential rates it costs about $114 a year in North Dakota (12.3¢/kWh) and $430 in Hawaii (46.6¢/kWh).

Keep digging