Electric Tankless Water Heater Energy Cost Calculator
On-demand electric water heater that heats water only when needed, eliminating standby heat loss.
Power Draw
18,000W
watts
Annual kWh
2,920
avg usage
Annual Cost
$380
avg national
CO₂/Year
2.1 tons
carbon impact
Electric Tankless Water Heater Cost Calculator
Customize usage and your state's electricity rate for accurate cost estimates.
Daily Cost
$2.34
Monthly Cost
$71.17
Annual Cost
$854
Lifetime Cost
$17,082
Energy Saving Opportunities
Save up to 24% vs standard models
~$205/year savings
Smart scheduling saves 15% more energy
~$128/year savings
Energy Saving Tips
- ✓Install point-of-use units for remote fixtures
- ✓Size properly for peak demand
- ✓Consider electrical upgrade
Compare Alternatives
| Appliance | Watts | Annual kWh | Annual Cost |
|---|---|---|---|
| Electric Tankless Water Heater (current) | 18,000W | 2,920 | $380 |
| Heat Pump Water Heater | 500W | 1,095 | $142 |
Electric Tankless Water Heater Cost Summary
Electric Tankless Water Heater Energy FAQ
Electric Tankless Water Heater Running Cost by City (top 100)
Electricity rates vary by city, so the cost to run an electric tankless water heater does too. See your local cost:
Methodology & Energy Data Sources — Electric Tankless Water Heater
How we calculate Electric Tankless Water Heater energy costs: Our calculations use EIA (US Energy Information Administration) residential electricity price data, cross-referenced with ENERGY STAR appliance efficiency standards and DOE Appliance and Equipment Standards. Wattage values reflect nameplate ratings from manufacturer specifications, normalized by the ENERGY STAR Testing & Certification Program.
- Wattage (18000W): Nameplate wattage from ENERGY STAR certified product database. Actual consumption may vary ±15% based on usage patterns and age of appliance.
- Annual kWh (2920 kWh): Calculated as (Wattage × Avg Hours/Day × Avg Days/Year) ÷ 1,000. Usage hours based on RECS (Residential Energy Consumption Survey) typical usage patterns for Water Heating equipment.
- Annual cost ($380): Calculated using EIA Form EIA-861M national residential average electricity rate. State-level rates sourced from EIA Electric Power Monthly (Table 5.6.A).
- Lifetime energy cost: Projects 2920 kWh/year × 20-year lifespan, adjusted for 2.5% annual electricity price escalation per EIA Annual Energy Outlook baseline scenario.
- Carbon footprint (2.1 lbs CO₂/year): Uses EPA eGRID national average emission factor (0.386 kg CO₂e/kWh for 2023). Regional factors vary significantly — see EPA eGRID subregion data for local estimates.
- EIA Electric Power Monthly — residential electricity rates
- EIA Residential Energy Consumption Survey (RECS)
- ENERGY STAR Certified Products Database
- EPA eGRID — electricity emission factors
- DOE Appliance and Equipment Standards Program
Disclaimer: Energy cost estimates are based on national and state averages. Actual costs depend on your utility's rate structure, time-of-use pricing, demand charges, and actual usage patterns. Contact your utility for exact rates and consider a home energy audit for personalized recommendations.
Reviewed by Brazora Monk · Last updated 2026 · EIA data current as of latest Electric Power Monthly release
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