What is a kilowatt-hour (kWh)?
Mark Whelan
Staff Writer

A kilowatt-hour (kWh) is the unit of measurement used by gas and electricity suppliers. One kilowatt-hour is equivalent to 1000 watts of energy used for 1 hour. For example, a 100-watt lightbulb switched on for 10 hours uses one kWh of electricity.

What is a kilowatt?

A kilowatt simply refers to 1,000 watts. It's a measure of power.

A kilowatt-hour, on the other hand, measures the usage of 1,000 watts of energy in the space of one hour. It's a measure of consumption.

What does 1 kilowatt-hour get me?

On average, Irish households consume 11.5 kWh of electricity and 30.1 kWh of gas per day. That's about 350 kWh of electricity and 917 kWh of gas every month.

Here’s what 1 kilowatt-hour will get you:

  • 10 minutes in an electric shower or one cycle of your washing machine or dishwasher.
  • About 30 mins of tumble drying or cooking with one large ring will also use up about one kWh each.
  • Half an hour of kettle use.
  • About 6 hours of TV-watching or desktop computer use.

Curious about what appliances use the most electricity? Take a look at this guide.

How are my gas and electricity bills calculated?

When it comes time for your gas and electricity suppliers to calculate your bill, they look at how many kWhs you have consumed during the billing cycle, multiply that number by their unit rate, add in taxes and standing charges and voila, there's the amount you have to pay.

It's important to note that gas and electricity suppliers often estimate the number of kWhs you have used, so it's important to regularly provide up to date meter readings to ensure that you're only billed for what you used. Here’s a guide on how to read your gas and electricity meter.

You'll know that your bill has been estimated by the big 'E' that appears on your bill. 

If you think that your supplier's estimate is higher than your actual consumption, you should provide them with a fresh meter reading and request that your bill be amended.

How can I monitor my usage?

We know that you’re not going to count every minute of usage for every electrical appliance in your house. Thankfully, you can get a great little gadget to do this for you. An Owl electricity monitor will cost you about €50 and, if used correctly, will pay for itself in no time.

Easily compare energy prices today

On bonkers.ie it’s easy to compare prices for both gas and electricity to find the cheapest deals available.

Try out our easy-to-use energy comparison tool to find out how much you could save today. Our service compares the very best electricity, gas, and dual fuel deals across all energy suppliers nationwide.

If you found this guide useful, we have a variety of different gas and electricity guides that will help you make informed decisions. Why not check out the following?

You can take a look at our full range of gas and electricity guides here.

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