WattCost

Data through June 2026

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

Navien NWP500S050AUMB

For a standard household draw pattern, the Navien NWP500S050AUMB uses a certified 840 kWh per year: roughly $154 annually at the national average rate. That puts it in the most efficient tenth of every certified electric water heater — 31% less electricity than the median, ranked 26 of 510. Where you live moves the bill from $110 a year in Nevada to $443 in Hawaii.

Dimensions 63" H × 21.8" W

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

$154/yr

$125 · cheapest certified water heaters (electric)$319 · priciest
Per month
$12.84
Per day
42¢
Certified use
840 kWh/yr
Type
Hybrid/Electric Heat Pump
Heat pump type
240 Volt Integrated HPWH
Storage volume
44 gal
First-hour rating
65 gal
UEF
3.85
681 kWh1,741 kWh
Where the Navien NWP500S050AUMB (▮) sits among all 510 certified water heaters (electric), by annual kWh

What it costs in every state

Navien NWP500S050AUMB: 840 kWh/yr × each state's average residential rate (EIA)
StateRate ¢/kWhThis model $/yrRelative cost
Alabama16.4¢$138
Alaska28.2¢$237
Arizona15.2¢$128
Arkansas14.1¢$119
California34.7¢$292
Colorado17.1¢$144
Connecticut24.3¢$204
Delaware19.3¢$162
District of Columbia24.4¢$205
Florida15.1¢$127
Georgia16.4¢$137
Hawaiipriciest52.7¢$443
Idaho14.4¢$121
Illinois19.9¢$167
Indiana17.5¢$147
Iowa15.9¢$134
Kansas15.7¢$132
Kentucky14.3¢$120
Louisiana13.5¢$113
Maine29.6¢$249
Maryland21.8¢$183
Massachusetts29.6¢$249
Michigan23.0¢$193
Minnesota17.5¢$147
Mississippi14.9¢$125
Missouri16.2¢$136
Montana15.1¢$127
Nebraska13.3¢$111
Nevadacheapest13.1¢$110
New Hampshire27.0¢$227
New Jersey24.9¢$210
New Mexico15.1¢$127
New York29.5¢$248
North Carolina14.7¢$124
North Dakota14.1¢$119
Ohio19.2¢$161
Oklahoma14.3¢$120
Oregon16.3¢$137
Pennsylvania21.7¢$183
Rhode Island29.2¢$246
South Carolina15.6¢$131
South Dakota15.4¢$129
Tennessee14.1¢$118
Texas15.9¢$134
Utah13.4¢$112
Vermont24.4¢$205
Virginia17.2¢$145
Washington14.9¢$125
West Virginia15.4¢$130
Wisconsin19.6¢$164
Wyoming15.2¢$128

Certified models closest in efficiency

electric water heaters within reach of 840 kWh/yr
ModelkWh/yr$/yr (US avg)
Arctic Arctic-HP-Hot Water-KA06-50837$154
PHNIX KA06-50837$154
Rinnai REHP50844$155
Rinnai REHP50BM844$155
Rinnai REHP50C844$155
Bradford White RE2HP50**-1NCTT835$153

Run your own numbers

Your rate, your numbers

Per day
42¢
Per month
$12.84
Per year
$154

840 kWh/yr × 18.3¢/kWh = $154/yr

Prefilled with this model's certified 840 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 Navien NWP500S050AUMB use?
ENERGY STAR certifies the Navien NWP500S050AUMB at 840 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 Navien NWP500S050AUMB cost to run per month?
About $12.84 a month at the U.S. average residential rate (18.3¢/kWh) — 42¢ a day, or $154 a year. Your state's rate moves this up or down; see the table above.
Is the Navien NWP500S050AUMB energy efficient?
It uses 31% less electricity than the median certified electric water heater, placing it in the top 10% of certified models.
What does the Navien NWP500S050AUMB cost to run in the cheapest vs. priciest state?
At current residential rates it costs about $110 a year in Nevada (13.1¢/kWh) and $443 in Hawaii (52.7¢/kWh).

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