WattCost

Data through April 2026

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

Rheem XE40T10HM00U0

For a standard household draw pattern, the Rheem XE40T10HM00U0 uses a certified 780 kWh per year: roughly $147 annually at the national average rate. Only a handful of certified electric water heaters do better: it ranks 18 of 566 and undercuts the median by 28%. The same unit costs $96 a year in North Dakota but $364 in Hawaii — electricity rates, not the appliance, make the difference.

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

$147/yr

$121 · cheapest certified water heaters (electric)$328 · priciest
Per month
$12.24
Per day
40¢
Certified use
780 kWh/yr
Type
Hybrid/Electric Heat Pump
Heat pump type
120 Volt Integrated HPWH
Storage volume
36 gal
First-hour rating
45 gal
UEF
2.8
643 kWh1,741 kWh
Where the Rheem XE40T10HM00U0 (▮) sits among all 566 certified water heaters (electric), by annual kWh

What it costs in every state

Rheem XE40T10HM00U0: 780 kWh/yr × each state's average residential rate (EIA)
StateRate ¢/kWhThis model $/yrRelative cost
Alabama17.4¢$136
Alaska27.4¢$213
Arizona15.5¢$121
Arkansas14.2¢$110
California35.3¢$275
Colorado16.5¢$129
Connecticut32.2¢$251
Delaware18.8¢$147
District of Columbia25.4¢$198
Florida15.4¢$120
Georgia15.4¢$120
Hawaiipriciest46.6¢$364
Idaho12.7¢$99
Illinois20.5¢$160
Indiana17.9¢$140
Iowa13.9¢$108
Kansas15.8¢$123
Kentucky15.0¢$117
Louisiana14.4¢$113
Maine28.4¢$222
Maryland22.1¢$172
Massachusetts29.4¢$230
Michigan21.4¢$167
Minnesota16.4¢$128
Mississippi16.8¢$131
Missouri14.0¢$109
Montana13.9¢$108
Nebraska13.3¢$104
Nevada14.3¢$111
New Hampshire27.2¢$212
New Jersey23.5¢$184
New Mexico15.2¢$118
New York29.4¢$230
North Carolina16.3¢$127
North Dakotacheapest12.3¢$96
Ohio19.5¢$152
Oklahoma13.3¢$104
Oregon15.8¢$123
Pennsylvania21.5¢$167
Rhode Island28.3¢$221
South Carolina17.1¢$133
South Dakota14.5¢$113
Tennessee14.9¢$117
Texas17.0¢$133
Utah13.3¢$104
Vermont24.6¢$192
Virginia17.4¢$136
Washington14.4¢$112
West Virginia16.1¢$125
Wisconsin19.2¢$150
Wyoming14.7¢$115

Certified models closest in efficiency

electric water heaters within reach of 780 kWh/yr
ModelkWh/yr$/yr (US avg)
Friedrich PROH40 T0 FD120-M780$147
Friedrich PROH40 T0 FD120-MSO780$147
Rheem PROPH40 T0 RH120-M780$147
Rheem PROPH40 T0 RH120-MSO780$147
Rheem XE40T10HMS00U0780$147
Richmond 10E40-HP120M780$147

Run your own numbers

Your rate, your numbers

Per day
40¢
Per month
$12.24
Per year
$147

780 kWh/yr × 18.8¢/kWh = $147/yr

Prefilled with this model's certified 780 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 Rheem XE40T10HM00U0 use?
ENERGY STAR certifies the Rheem XE40T10HM00U0 at 780 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 Rheem XE40T10HM00U0 cost to run per month?
About $12.24 a month at the U.S. average residential rate (18.8¢/kWh) — 40¢ a day, or $147 a year. Your state's rate moves this up or down; see the table above.
Is the Rheem XE40T10HM00U0 energy efficient?
It uses 28% less electricity than the median certified electric water heater, placing it in the top 10% of certified models.
What does the Rheem XE40T10HM00U0 cost to run in the cheapest vs. priciest state?
At current residential rates it costs about $96 a year in North Dakota (12.3¢/kWh) and $364 in Hawaii (46.6¢/kWh).

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