Science Common Sense


1376 - What is the relationship between electrical appliance labels and electricity cost calculation?

The labels on electrical appliances, like your refrigerator or TV, have a rating that shows how much electricity they use, usually in watts (W). This is called the 'wattage' or 'power consumption'.

When you know the wattage and how many hours you use the appliance in a day, you can calculate how much electricity it uses per day. To do this, multiply the wattage by the hours used.

For example: A TV uses 150W, and you watch it for 4 hours. 150W x 4 hours = 600 watt-hours (Wh)

To find out how much electricity this is in kilowatt-hours (kWh), divide the result by 1000. 600 Wh / 1000 = 0.6 kWh

Now, if you know how much your electricity costs per kWh (usually shown on your electricity bill), you can multiply the kWh by the cost to find out how much the appliance costs to run for one day.

For example: If electricity costs 20 cents per kWh, then: 0.6 kWh x 20 cents/kWh = 12 cents

So, the TV costs 12 cents to run for 4 hours.

Repeat this process for all appliances, and you can calculate your total electricity cost.