An appliance’s electricity consumption depends on its power, operating time and how it is used. An appliance running for just a few minutes may therefore consume less electricity overall than another operating for several hours.

Electric heating, water heating, cooking and tumble drying generally deserve the most attention. However, their contribution to your electricity bill varies according to your household’s habits.

Which Appliances Have the Biggest Impact on Your Electricity Bill?

Electric Heaters

Fan heaters, convector heaters and electric radiant heaters can consume substantial energy when used for several hours every day.

For example, a 2,000W heater uses 8 kWh when running continuously at full power for four hours. Consumption is lower when it operates at a reduced setting or its thermostat switches the heating off periodically.

Electric Water Heaters

Consumption depends on the amount of hot water needed, the temperature setting and heat losses from the tank. A 4,000W heating element, active for half an hour, consumes 2 kWh.

Air Conditioners

Electricity use depends on operating hours, insulation, outdoor temperature and temperature settings. BTU ratings indicate heating or cooling capacity, rather than electrical consumption.

When choosing an air conditioner, check its energy label and seasonal efficiency ratings: SEER for cooling and SCOP for heating. 

Tumble Dryers, Ovens and Hobs

Frequent tumble drying and long cooking times can noticeably increase total electricity consumption.

For tumble dryers, compare energy consumption per cycle. For ovens and hobs, temperature, programme and operating time all matter. Their heating elements do not necessarily run continuously at maximum power.

Refrigerators and Freezers

These appliances remain switched on around the clock, although their compressors do not run continuously. When comparing models, check annual energy consumption in kWh.

A refrigerator rated at 240 kWh per year corresponds to an average of 20 kWh per month, under the label’s test conditions. Actual consumption depends on room temperature, settings and how often the door is opened.

Washing Machines and Dishwashers

Programme selection, temperature and frequency of use determine electricity consumption. Energy labels show kWh per 100 cycles of the relevant Eco programme, allowing models to be compared under standardised conditions. 

How Do You Calculate an Appliance’s Running Cost?

For an appliance operating at a constant power:

Energy consumption = power in kW × operating hours

Then:

Energy cost = consumption in kWh × electricity price per kWh

Using a hypothetical electricity price of €0.20/kWh, the following examples illustrate the calculation:

These calculations are illustrative and do not include every charge on an electricity bill. They demonstrate why operating time matters just as much as wattage.

What Should You Check Before Buying a New Appliance?

Compare models within the same category and with similar capacities. Consider their stated energy consumption, features and the size you actually need. The energy efficiency class is useful, but it should not be your only criterion.

Summary

Appliances that run for many hours or generate heat can contribute significantly to your electricity bill. However, comparing power ratings alone is not enough: total consumption depends on operating time, settings and each model’s efficiency. Check the kWh figures on the energy label and choose appliances suited to your actual needs.