What is a kWh and how much does it cost

For most people when they look at their electricity and gas bills, the first thing they check is the total cost, making sure there are no surprises with large credit or debit balances. After that they may check their meter readings and match them up to those stated on their bill.

What most people miss, or skim over, are the number of kilowatt hours (kWh) that have been used. Having knowledge of kWh can be extremely useful as it will help you understand how much energy you're using, what you're paying for it, and helping you save on future bills.

What is a kWh?

A kilowatt hour (kWh) is a unit for measuring how much gas and electricity you're using with the unit measurement equal to the usage of 1,000 watts per hour.

This means that if an appliance uses 1,000 watts (1kW) to work, if that appliance was left running for an hour it would have used 1 kilowatt hour (1kWh) of energy. If you were to continue to use the same appliance for 3 hours then you would have used 3 kWh of energy.

Energy suppliers use kWh to measure energy usage over a period of time and the amount you would pay would vary between providers.

What's the difference between kW and a Kwh?

A kilowatt (kW) is equal to 1,000 watts and is a measure of power, helping to record how much electricity an appliance needs to work. A kilowatt hour (kWh) is a measurement of energy and this unit will show how many kilowatts are needed to power an appliance for any given time.

Why is it useful to know about kW and kWh?

Being able to distinguish between kW and kWh will help when digesting your energy bills and understanding which appliances are using the most energy.

It can also help when purchasing a new appliance. Always look for the power rating, which is usually located on the appliance itself or its packaging. This rating will show how much electricity is needed for it to work and will give you an insight into how much energy it will use up.

Low wattage appliances may seem appealing but make sure you shop around before committing to purchasing. Some machines that need more power to operate may actually be more efficient than low watt counterparts, using less energy. On the other hand, lower wattage appliances may trump energy-efficient ones if left on for longer period.

It is a case of reviewing each new appliance and understanding the use for it, aiming to be as efficient as possible.

What does 1 kWh equate to?

As mentioned above, similar appliances can vary in wattage but as a rough estimate, the below are some examples of appliances using 1kWh:

  • A plasma TV (200 watts) being left on for 5 hours.
  • A microwave (1,000 watts) being used for an hour.
  • An electric water heater (4,500 watts) being used for 13 minutes.
  • A laptop (100 watts) being plugged in for 10 hours
  • A dishwasher (1,500 watts) being used for 40 minutes.
  • An iron (1,200 watts) being used for
  • An LED lightbulb (18 watts) being used for 56 hours.
  • An electric clothes dryer (3,000 watts) being used for 20 minutes.

You can use our electricity cost calculator to help you see how much each of your household items are costing to run each month. From there, we will take this cost and run an energy price comparison for you to find the best energy deal on the market and show how much you can save by switching.

What should I be paying per KwH?

The energy price per kWh will vary between different energy suppliers and can be fluctuate dependent on the tariff you're on or what type of meter you're using. Location can also have a bearing on the price as you might pay more per kWh due to demand in the area and the difficulty/ease in supplying energy from the National Grid.

If you're using certain appliances at specific times of the day, an Economy 7 or Economy 10 meter may help to save money as the price for kWh will be lower in the evening and throughout the night.

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