How to measure an appliance's electricity use

If you want to know where your electricity goes, start by measuring. Estimates based only on the manufacturer's rated power may differ from real-world use.

1. What you need

A plug-in energy meter can record values such as power and accumulated energy. There are simple display models as well as Wi-Fi plugs with app-based monitoring.

2. How to measure

Connect the meter to a suitable outlet.
Connect the appliance to the meter.
Record the starting kWh value.
Use the appliance for a representative period.
Check the kWh again and calculate the difference.

Example: if an appliance uses 3 kWh over 10 days, its average is 0.3 kWh/day. Over 30 days, that is about 9 kWh/month.

3. Convert kWh to euros

As a simple estimate, multiply kWh by the electricity price you want to use as a reference. For example, 9 kWh × €0.18/kWh = €1.62. A real bill can include other charges.

4. What should you measure?

Start with appliances that run for many hours or have high power: refrigerators, computers, televisions, dehumidifiers, heaters, pumps and climate-control equipment.

5. Which meter?

There are basic meters with a screen and smart Wi-Fi plugs with energy monitoring. Prices and availability vary by seller and date.