How is electricity measured?
So one kilowatt hour (1 kWh) is the amount of energy you’d use if you kept a 1 kW appliance running for one hour.
Which appliances cost the most to run?
So, how can you keep your consumption – and bills – as low as possible?
Step one is knowing which appliances use the most electricity. Step two is being smart about when and how often you use them.
When you buy any appliance, its handbook will tell you how much energy it uses. So try not throw this out.
In general, the higher the kW, the more energy it uses. So for example a 3 kW appliance will use three times as much energy as a 1 kW device for every hour of usage and five times as much energy as a 600 watt (0.6 kW) device.
However many appliances such as washing machines, dishwashers, fridges and computers only operate at their max wattage for very short periods which can make calculating their exact energy consumption and cost difficult.
But a good rule of thumb is: if it makes things hot, particularly in a short space of time, it costs a lot. Think kettles, hair dryers, tumble dryers and electric showers – they all have a ferocious appetite for electricity. An electric oven is also a big energy guzzler and can cost up to €1 an hour to run.
So let’s look at what running a few appliances over the course of a day could cost you.
Note: your actual costs will depend on the energy efficiency of the appliance you use, its size, and of course the unit rate you pay for your electricity. A G-rated 55" TV will use a lot more energy than a C-rated 42" TV for example.
Most modern appliances (particularly washing machines, tumble dryers, dishwashers and TVs) are way more efficient than older models, but the rating will help you choose the most efficient model. The ratings, which are compulsory, range from A to G, with A being the most efficient.
|Energy of appliance
|Cost inc. VAT at 9%*
|2 hours to fully heat 120-litre tank from cold
|One hour of drying
|One hour of cooking
|Dishwasher (D rated)**
|1.5 kW per cycle
|Standard 65º cycle
|Washing machine (D rated)**
|1 kW per cycle
|Standard 40º cotton wash
|8 hours of use
|0.18 kW/350 kWh annual
|One day running
|Half hour of ironing
|0.18 kW/180 Watts
|4 hours of use
|8 hours of use
|TV (55" F rated)**
|100 kW per 1,000 hours
|4 hours of use
|Lightbulb 60 Watt
|6 hours of light
|10 mins of use
|0.7 kW / 700 Watts
|20 mins of hoovering
|One day's use
|5 mins of boiling/two cups of tea
|10 mins of use
|5 mins of use
|5 mins of use/two cups of coffee
|Daily standing charge
|One day (reduced from 1 October 2022)
*based on Electric Ireland's standard 24-hour urban rate of €0.36 per kWh including VAT as of March 2024. Rounding has been applied to all figures. Cheaper rates at certain times of the day may be available for those with smart meters or night saver meters.
**Based on the new rating scale launched in 2021. These would have been rated A or B under the old scale. See here for more info on the new rating system.
***Cost has taken into account that these appliances won't operate at their max energy output for most of the time.
You're highly unlikely to use all of the above appliances every day, and smaller households definitely won't.
But as you can see, at current rates, an extremely busy day in a large home could cost just over €8 - and that's before you've even turned on the heat!
You can also see how expensive heating water is - unless you have solar panels. So make sure you have a good lagging jacket for your tank and don't leave hot taps running as you're literally pouring money down the drain!
Turn it off
There's a misconception among many Irish people that turning on and off appliances regularly uses excess electricity and that it may be better to keep appliances on for most of the time.
This is wrong - especially when it comes to newer and more modern devices.
If you're leaving the room, even if only for a few minutes, you'll save money by turning off the lights, the TV or the portable heater etc.
The same rule applies to the immersion. Only keep it on for when you need hot water. Don't leave it on 24/7 - as it'll just increase your bill.
How can I monitor my electricity usage?
If you have a smart meter, and sign up to a smart electricity tariff, your supplier should be able to provide you with lots of up-to-the-minute info on your usage.
You can also buy energy monitoring plugs, which are available cheaply on sites like Amazon. These will let you see exactly how much energy each appliance is using.
How can I use less energy?
Being energy efficient is both good for the environment as well as your pocket. With that in mind, here's a list of 16 easy ways to reduce your electricity consumption, lower your bills, and do your bit for the planet.
And if you're looking to save even more money while continuing to reduce your impact on the environment, follow these 12 easy tips to use less water and save money and check out this great list of ways to reduce your carbon footprint, while saving on your everyday expenses.
However, the best way to save on your electricity bills is to switch to a cheaper supplier...
Switch and save
Most suppliers offer big discounts for an entire year to those who switch.
So switching to a new provider is a great way to cut down on your electricity costs.
Discover all you need to know about the energy comparison and switching process in our Quickstart Guide.