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Data through July 2026

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

Rheem PROPH40 T2 RH375-15

Heating a typical household's hot water, the Rheem PROPH40 T2 RH375-15 is certified at 643 kWh a year — about $118 at the U.S. average electricity rate, or $9.81 a month. That puts it in the most efficient tenth of every certified electric water heater — 42% less electricity than the median, ranked 2 of 605. Where you live moves the bill from $82 a year in Louisiana to $309 in Hawaii.

Dimensions 62.3" H × 20.3" W

Estimated annual running cost · U.S. average rate 18.3¢/kWh

$118/yr

$118 · cheapest certified water heaters (electric)$319 · priciest
Per month
$9.81
Per day
32¢
Certified use
643 kWh/yr
Type
Hybrid/Electric Heat Pump
Heat pump type
240 Volt Integrated HPWH
Storage volume
36 gal
First-hour rating
46 gal
UEF
3.45
643 kWh1,741 kWh
Where the Rheem PROPH40 T2 RH375-15 (▮) sits among all 605 certified water heaters (electric), by annual kWh

What it costs in every state

Rheem PROPH40 T2 RH375-15: 643 kWh/yr × each state's average residential rate (EIA)
StateRate ¢/kWhThis model $/yrRelative cost
Alabama16.4¢$105
Alaska28.8¢$185
Arizona15.4¢$99
Arkansas14.3¢$92
California33.6¢$216
Colorado17.0¢$109
Connecticut24.2¢$155
Delaware18.5¢$119
District of Columbia25.2¢$162
Florida15.0¢$97
Georgia16.3¢$105
Hawaiipriciest48.0¢$309
Idaho13.7¢$88
Illinois19.2¢$124
Indiana16.7¢$108
Iowa16.0¢$103
Kansas15.3¢$98
Kentucky13.8¢$89
Louisianacheapest12.7¢$82
Maine32.4¢$208
Maryland21.4¢$138
Massachusetts30.5¢$196
Michigan23.1¢$148
Minnesota17.4¢$112
Mississippi14.5¢$93
Missouri16.1¢$103
Montana15.0¢$96
Nebraska13.8¢$89
Nevada12.8¢$82
New Hampshire26.6¢$171
New Jersey25.2¢$162
New Mexico16.1¢$103
New York29.9¢$192
North Carolina15.2¢$97
North Dakota13.4¢$86
Ohio19.4¢$125
Oklahoma14.3¢$92
Oregon16.0¢$103
Pennsylvania21.7¢$140
Rhode Island28.3¢$182
South Carolina15.5¢$99
South Dakota15.4¢$99
Tennessee13.7¢$88
Texas15.9¢$102
Utah13.1¢$84
Vermont23.8¢$153
Virginia17.6¢$113
Washington14.7¢$95
West Virginia15.8¢$101
Wisconsin19.1¢$123
Wyoming14.4¢$92

Certified models closest in efficiency

electric water heaters within reach of 643 kWh/yr
ModelkWh/yr$/yr (US avg)
Friedrich PROH40 T2 FD400-15643$118
Rheem PROPH40 T2 RH400-15643$118
Rheem XE40T10H22U0643$118
Rheem XE40T10H22U1643$118
Richmond 10E40-HP5U15643$118
Ruud PROUH40 T2 RU375-15643$118

Run your own numbers

Your rate, your numbers

Per day
32¢
Per month
$9.81
Per year
$118

643 kWh/yr × 18.3¢/kWh = $118/yr

Prefilled with this model's certified 643 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 PROPH40 T2 RH375-15 use?
ENERGY STAR certifies the Rheem PROPH40 T2 RH375-15 at 643 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 PROPH40 T2 RH375-15 cost to run per month?
About $9.81 a month at the U.S. average residential rate (18.3¢/kWh) — 32¢ a day, or $118 a year. Your state's rate moves this up or down; see the table above.
Is the Rheem PROPH40 T2 RH375-15 energy efficient?
It uses 42% less electricity than the median certified electric water heater, placing it in the top 10% of certified models.
What does the Rheem PROPH40 T2 RH375-15 cost to run in the cheapest vs. priciest state?
At current residential rates it costs about $82 a year in Louisiana (12.7¢/kWh) and $309 in Hawaii (48.0¢/kWh).

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