WattCost

Data through June 2026

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

Rinnai REHP50CW

Heating a typical household's hot water, the Rinnai REHP50CW is certified at 861 kWh a year — about $158 at the U.S. average electricity rate, or $13.16 a month. That's 29% less than the median certified electric water heater, placing it comfortably in the efficient third of the field (72 of 510). Where you live moves the bill from $113 a year in Nevada to $454 in Hawaii.

Dimensions 46.6" H × 18.3" W

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

$158/yr

$125 · cheapest certified water heaters (electric)$319 · priciest
Per month
$13.16
Per day
43¢
Certified use
861 kWh/yr
Type
Hybrid/Electric Heat Pump
Heat pump type
240 Volt Integrated HPWH
Storage volume
46 gal
First-hour rating
71 gal
UEF
3.75
681 kWh1,741 kWh
Where the Rinnai REHP50CW (▮) sits among all 510 certified water heaters (electric), by annual kWh

What it costs in every state

Rinnai REHP50CW: 861 kWh/yr × each state's average residential rate (EIA)
StateRate ¢/kWhThis model $/yrRelative cost
Alabama16.4¢$141
Alaska28.2¢$243
Arizona15.2¢$131
Arkansas14.1¢$122
California34.7¢$299
Colorado17.1¢$147
Connecticut24.3¢$209
Delaware19.3¢$166
District of Columbia24.4¢$210
Florida15.1¢$130
Georgia16.4¢$141
Hawaiipriciest52.7¢$454
Idaho14.4¢$124
Illinois19.9¢$171
Indiana17.5¢$151
Iowa15.9¢$137
Kansas15.7¢$135
Kentucky14.3¢$123
Louisiana13.5¢$116
Maine29.6¢$255
Maryland21.8¢$188
Massachusetts29.6¢$255
Michigan23.0¢$198
Minnesota17.5¢$151
Mississippi14.9¢$128
Missouri16.2¢$140
Montana15.1¢$130
Nebraska13.3¢$114
Nevadacheapest13.1¢$113
New Hampshire27.0¢$233
New Jersey24.9¢$215
New Mexico15.1¢$130
New York29.5¢$254
North Carolina14.7¢$127
North Dakota14.1¢$122
Ohio19.2¢$165
Oklahoma14.3¢$123
Oregon16.3¢$141
Pennsylvania21.7¢$187
Rhode Island29.2¢$252
South Carolina15.6¢$134
South Dakota15.4¢$132
Tennessee14.1¢$121
Texas15.9¢$137
Utah13.4¢$115
Vermont24.4¢$210
Virginia17.2¢$148
Washington14.9¢$128
West Virginia15.4¢$133
Wisconsin19.6¢$168
Wyoming15.2¢$131

Certified models closest in efficiency

electric water heaters within reach of 861 kWh/yr
ModelkWh/yr$/yr (US avg)
Midea CAN3-RSJ-15/190RDVN3-L4861$158
Midea MAHW-50VN3B861$158
Midea MCHW-50VN3B861$158
Midea US3-RSJ-15/190RDVN3-L4861$158
Rinnai REHP50W861$158
LG R5TT20F-SA0 (208V)866$159

Run your own numbers

Your rate, your numbers

Per day
43¢
Per month
$13.16
Per year
$158

861 kWh/yr × 18.3¢/kWh = $158/yr

Prefilled with this model's certified 861 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 Rinnai REHP50CW use?
ENERGY STAR certifies the Rinnai REHP50CW at 861 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 Rinnai REHP50CW cost to run per month?
About $13.16 a month at the U.S. average residential rate (18.3¢/kWh) — 43¢ a day, or $158 a year. Your state's rate moves this up or down; see the table above.
Is the Rinnai REHP50CW energy efficient?
It uses 29% less electricity than the median certified electric water heater, placing it in the efficient third of certified models.
What does the Rinnai REHP50CW cost to run in the cheapest vs. priciest state?
At current residential rates it costs about $113 a year in Nevada (13.1¢/kWh) and $454 in Hawaii (52.7¢/kWh).

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