Electricity Consumption Calculator
Calculate the electricity cost of your appliances and find savings opportunities.
Household electricity consumption represents a significant part of the monthly bill, and knowing it precisely is the first step to reducing it. Each appliance has a power rating in watts (W) which, multiplied by daily hours of use, determines consumption in kilowatt-hours (kWh). The price per kWh varies by country, supplier and tariff contracted.
This calculator adds up the consumption of all the appliances you enter and shows you the daily, monthly and annual cost. The breakdown by appliance lets you quickly identify which are the most expensive and where you can save. Particularly useful for optimising the use of electric heaters, air conditioners and high-consumption appliances.
Calculated based on current average market prices.
Cost Summary
Reduce Air Conditioning usage by 10% to save €2.70 per month.
Consumption Distribution
Use A+++ rated appliances to reduce your consumption by up to 60% compared to older models.
Results are estimates based on nominal power and declared usage. Actual consumption may vary. Check your electricity bill for the exact price per kWh.
How it works
This calculator estimates electricity consumption by adding up the usage of each appliance based on its power in watts (W) and daily hours of use. The formula is:
Multiply by the kWh price to get the cost. The average price in Spain in 2026 is around €0.12/kWh, although it varies depending on the contracted tariff.
How electricity consumption is calculated
The formula is straightforward: consumption in kWh = (power in watts × hours of use) / 1,000. Dividing by a thousand converts watt-hours into kilowatt-hours, the unit your electricity company bills in. Once you know the consumption, the cost is obtained by multiplying it by your tariff's kWh price. Remember that the power stated on the label is the maximum the appliance can draw, not necessarily what it consumes continuously: a 150 W fridge does not use 150 W for 24 hours; its compressor cycles on and off, so real consumption is usually around a third of the theoretical figure.
Worked example
Let's work out the cost of a 1,500 W air conditioner used 4 hours a day for a month. Daily consumption is (1,500 × 4) / 1,000 = 6 kWh. Over a month, 6 × 30 = 180 kWh. At a price of €0.15/kWh, the monthly cost comes to 180 × 0.15 = €27. If that same unit were used only 2 hours a day, the cost would halve to about €13.50 a month. This calculation shows why high-power appliances are the first place to act when reducing your bill.
Indicative monthly consumption by appliance
| Appliance | Power | kWh/month |
|---|---|---|
| Fridge | 150 W | 108 |
| Air conditioning | 1.500 W | 180 |
| Electric oven | 2.000 W | 30 |
| Computer | 200 W | 48 |
| LED TV | 100 W | 18 |
| Washing machine | 500 W | 15 |
How to interpret the result
The total in kWh is useful for cross-checking against your actual bill: an average Spanish household uses between 250 and 300 kWh a month, so if your estimate is far from that range it is worth reviewing the data you entered. Look above all at which appliances account for the largest share of the total, because that is where any change has most impact: cutting air conditioning use by 20% saves far more than switching off every light bulb in the house. Bear in mind too that the electricity bill includes a fixed charge for contracted power, taxes and meter rental, so the final amount will always exceed the result of multiplying kWh by the energy price.