How much electricity does an electric water heater use?
An electric water heater for four people uses about 3,600 kWh of electricity a year, about 3,744 PLN at 1.04 PLN/kWh and about 312 PLN a month. One person accounts for about 900 kWh, about 936 PLN a year.
Example: 4 people × 900 kWh = 3,600 kWh
Electric water heater: about 3,600 kWh a year, about 3,744 PLN a year
about 3,744 PLN a yearabout 312 PLN a month
One use and average
- 1 person for a year
- 900 kWh, about 936 PLN
- Average per day
- 9.86 kWh, about 10.26 PLN
In the G12 night zone in the PGE network (0.6111 PLN/kWh): about 2,200 PLN a year.
Price from 11 October 2026, estimate
| Period | Use | Cost |
|---|---|---|
| Per day, average | 9.86 kWh | 10.26 PLN |
| Per month | 300 kWh | 312 PLN |
| Per year | 3,600 kWh | 3,744 PLN |
Assumptions and formulaPrice from 11 October 2026
kWh/yr = W × h/day × 365 ÷ 1000 kWh/yr = kWh per cycle × cycles per week × 52 cost = kWh/yr × price of 1 kWh
Your numbers
- Electric water heater: 4 people × 900 kWh = 3,600 kWh; 3,600 kWh × 1.04 PLN = about 3,744 PLN a year
- Electricity price
- 1.04 PLN/kWhURE G11 tariffs 2026 (PGE, Tauron, Enea, Energa), average with distribution
- G12 night zone in the PGE network
- 0.6111 PLN/kWhPGE Obrót and PGE Dystrybucja tariffs for 2026, gross, without fixed charges
- Hot water per person a year
- 900 kWhas in the heating cost calculator
- Year
- 365 days, 52 weeks
- Rounding
- to 1 kWh a year, below 10 kWh to 0.1 kWh
An estimate. Fixed charges on the bill are not included. Appliances with a thermostat (fridge, oven, water heater) draw full power only part of the time, so label data works better for them.
How electricity, gas, pellet and coal prices have changed, month by month. Price history
Ready-made calculations
Where 900 kWh per person comes from
The calculator assumes 900 kWh of heat per person a year for hot water, the same as the heating cost calculator. A heating element turns electricity into heat almost 1:1, so the water heater draws the same number of kWh. Heat lost from the tank is left out, so real use may be higher.
Water heater on the G12 tariff
A water heater can heat water only at night and use the stored supply during the day. In the G12 night zone in the PGE network 1 kWh costs 0.6111 PLN, so the same heater costs about 2,200 PLN a year, about 1,544 PLN less.
The G12 tariff changes the price for the whole meter, and daytime electricity on it costs more than on G11. Work out the whole house before you switch.
Frequently asked questions
How much does an electric water heater cost per month?
For four people about 312 PLN a month at 1.04 PLN/kWh. For two people about 156 PLN.
Does a bigger water heater use more electricity?
Only a little. Use depends mainly on how much hot water the household uses, while the size affects heat loss from the tank and whether the night supply lasts all day.
Is it worth heating water at night?
If you are on the G12 tariff, yes: in the PGE network a night kWh costs 0.6111 PLN instead of 1.04 PLN on average on G11. For four people that is about 1,544 PLN a year less for hot water.