Electric Tankless Water Heater in Honolulu — $2,795/yr to Run (42.5¢/kWh)
Your electric tankless water heater in Honolulu costs about $233/month at 42.5¢/kWh. See daily, monthly, and yearly costs, plus tips to cut your bill.
Honolulu, HI Electricity Rate
42.5¢/kWh
Utility: Hawaiian Electric (HECO)
+227% vs national avg
National avg: 13.0¢/kWh
Daily Cost
$7.66
18.0 kWh/day
Monthly Cost
$232.91
548 kWh/mo
Annual Cost
$2,795
6,570 kWh/yr
Lifetime (20yr)
$55,898
energy only
Monthly Cost Breakdown in Honolulu
| Period | kWh | Honolulu Cost | National Avg | Difference |
|---|---|---|---|---|
| Daily | 18.0 | $7.66 | $2.34 | +$5.32 |
| Weekly | 126.0 | $53.60 | $16.38 | +$37.22 |
| Monthly | 547.5 | $232.91 | $71.17 | +$161.73 |
| Quarterly | 1642.5 | $698.72 | $213.53 | +$485.19 |
| Annual | 6570.0 | $2794.88 | $854.10 | +$1940.78 |
Customize Your Electric Tankless Water Heater Cost
Adjust usage hours and electricity rate to calculate your exact cost in Honolulu.
Daily
$7.66
Monthly
$232.91
Annual
$2,795
20-Year
$55,898
Energy Saving Tips for Electric Tankless Water Heater in Honolulu
- ✓Honolulu electricity rates are 227% above the national average — energy efficiency matters more here.
- ✓An ENERGY STAR Electric Tankless Water Heater in Honolulu saves ~$671/year compared to standard models.
- ✓A smart Electric Tankless Water Heater with scheduling optimization can save ~$419/year at Honolulu rates.
- ✓Install point-of-use units for remote fixtures
- ✓Size properly for peak demand
- ✓Consider electrical upgrade
ENERGY STAR Savings: Upgrading to an ENERGY STAR Electric Tankless Water Heater in Honolulu saves approximately $671/year at local rates — $13,415 over the appliance lifetime.
Highest-Cost Appliances in Honolulu, HI
See which appliances cost the most to run at Honolulu's 42.5¢/kWh electricity rate.
Level 2 EV Charger (240V)
Transportation · 7,200W
$5,513/yr
$459.43/mo
Electric Furnace
HVAC · 10,000W
$3,829/yr
$319.05/mo
EV Charger (Level 2)
Garage · 7,200W
$2,757/yr
$229.72/mo
Boiler (Electric)
HVAC · 6,000W
$2,297/yr
$191.43/mo
Electric Water Heater (Tank)
Water Heating · 4,500W
$2,096/yr
$174.68/mo
Water Heater (Tank Electric)
Water Heating · 4,500W
$2,096/yr
$174.68/mo
Heat Pump
HVAC · 2,400W
$1,634/yr
$136.13/mo
Hot Tub / Spa
Pool & Spa · 3,000W
$1,531/yr
$127.62/mo
Electric Tankless Water Heater Cost in Other Hawaii Cities
| City | Rate | Annual Cost | vs Honolulu |
|---|---|---|---|
| Honolulu (current) | 42.5¢ | $2,795 | — |
| Maui | 41.5¢ | $2,729 | $-66 |
Electric Tankless Water Heater Energy Cost FAQ — Honolulu, HI
Understanding Electric Tankless Water Heater Energy Costs in Honolulu, HI
Honolulu is a mid-sized Hawaii city where residential electricity rates from Hawaiian Electric (HECO) are shaped by regional energy supply and local demand patterns. Running a high-draw appliance like the Electric Tankless Water Heater (18,000W) at Honolulu's rate of 42.5¢/kWh costs approximately $2,795 per year — $1941 more than the national average of $854.
Electricity in Honolulu is significantly more expensive than the national average — 227% higher. For a Electric Tankless Water Heater used 1 hours per day, this rate premium adds up to $1,941 in extra annual costs. Energy-efficient models and usage habits have an outsized impact in high-rate markets like this.
Honolulu has a high cost of living (index: 193), which means electricity is just one of many above-average expenses. Reducing appliance energy costs — even by small amounts — contributes to meaningful household savings in this market. Upgrading to an ENERGY STAR Electric Tankless Water Heater can cut energy use by up to 24%, saving approximately $671 per year at Honolulu rates.
In Honolulu's warm climate (avg 83.7°F), HVAC-related appliances tend to run more frequently, compounding energy costs. A Electric Tankless Water Heater produces approximately 2.1 tons of CO2 annually at typical usage. Honolulu residents can reduce this footprint by choosing an ENERGY STAR certified unit, optimizing usage patterns, or investing in solar — see our solar savings calculator for Honolulu.
Compare All Energy Costs in Honolulu
See energy costs for 178+ household appliances at Honolulu's local electricity rate.
Frequently Asked Questions
How much does it cost to run an Electric Tankless Water Heater in Honolulu, HI?
At Honolulu's average electricity rate of 42.5¢/kWh, an Electric Tankless Water Heater costs approximately $2,795 per year to run. That's about $232.91 per month with typical usage of 1 hours per day.
What is the electricity rate in Honolulu, HI?
The average residential electricity rate in Honolulu, HI is 42.5¢/kWh, which is 227% above the national average of 13.0¢/kWh. The primary utility provider is Hawaiian Electric (HECO).
How much electricity does an Electric Tankless Water Heater use per year?
A Electric Tankless Water Heater uses approximately 18,000 watts and consumes about 6,570 kWh per year with typical usage of 1 hours/day for 365 days/year.
Is an Electric Tankless Water Heater expensive to run in Honolulu?
Compared to the national average cost of $854/year, running an Electric Tankless Water Heater in Honolulu costs $1941 more per year due to higher local electricity rates.
How can I reduce my Electric Tankless Water Heater energy cost in Honolulu?
To reduce Electric Tankless Water Heater costs in Honolulu: Install point-of-use units for remote fixtures. Size properly for peak demand. Upgrading to an ENERGY STAR model saves up to 24% on energy costs. Also check with Hawaiian Electric (HECO) for local energy efficiency rebates and programs.