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What uses the most energy in my home?


The key to saving money and energy in your home is to prioritise what uses the most energy. A home that has the most efficient appliances in the world but a poor performing boiler could still be more expensive to run than a home with old appliances and the most efficient boiler. In this post, we look at what uses the most energy in your home, before taking a deep dive into some specific appliances.  

In this article:

The biggest energy users in your home

Heating and water heating should take priority over a brand new fridge or tumble dryer, for example, because together they account for almost half of a typical household’s energy bill [1]:

So, always try to remember this simply hierarchy:

1️⃣🔥 Focus on how you heat your home first. Use the most efficient heating system you can afford, reduce heat loss as much as you can, and then heat less space to as low a temperature as is comfortable and safe.

2️⃣ 💧Then look at water heating. Whether you’re taking showers, filling the kettle or running the washing machine, heat less water to as low a temperature as is comfortable and safe.

3️⃣ 📺 Finally look at your appliances. Maximise use of standby, use the most eco standby setting where a device has more than one (games consoles, set top boxes) and don’t worry about your mobile phone charger.


Almost 20% of UK homes have their thermostat set at 22°C or higher, despite energy experts recommending a comfortable range of 18˚C – 21°C. While every home will vary, and different people have different preferences, turning down the thermostat by 1°C can lead to savings of as much as 10% on your energy bill. Savings may be lower (or higher) than this depending on factors like the efficiency of your boiler efficiency, home insulation, and previous thermostat setting. Bear in mind that heating below 18°C or above 22°C can cause health problems.

In some homes, keeping your heating on at a low temperature at night or when you’re out can be cheaper than letting rooms cool down completely and reheating them from scratch,. Whether this will work for you depends on a number of factors. If you have a poorly insulated home, a boiler that doesn’t allow temperature automation, or a home that cools down quickly, this sort of ‘steady-state’ heating may not be the best option. However, if you have a well-insulated home, a condensing boiler, and internal walls made of brick or stone, steady-state heating may be more energy-efficient. If you’re not sure, try running some tests (although make sure you’re testing in periods with similar weather conditions to make sure you’re comparing like for like).

Water heating

Heating water is expensive, so whether you’re filling your kettle, choosing a washing machine setting, or taking a shower, always aim to heat as little water as possible to as low a temperature as possible.

Showers can be particularly expensive, but also offer a number of ways to cut bills and lower carbon emissions.

Our shower calculator shows that a daily, 7.5-minute shower will cost up to £175 per person per year at October 2022 Price Cap levels, with each minute in the shower costing around 6p. By reducing the average shower length to four minutes, a typical home could save up to £80 per person annually. The cost of showers and baths can be affected by various factors, including:

  • The number and length of showers;
  • Your boiler – Condensing boilers are more efficient, recycling exhaust gases and capturing extra heat, allowing them to operate at 90% efficiency or higher, wasting less energy than non-condensing boilers which may only operate at 70% efficiency;
  • Your shower’s ‘flow rate’ – the speed water passes through your shower affects how much water you use – and how much therefore has to be heated. Eco shower heads or screw-in flow reducers can help if you have a high flow rate; and
  • Your hot water temperature – The heat setting of your combi boiler or hot water tank affects the energy consumption of your shower. The hot water tank should be heated to at least 60°C periodically to prevent the growth of Legionella bacteria, but heating it above this temperature wastes energy as cold water needs to be mixed with the hot water to make it usable.

Clothes drying

Tumble dryers

On average, a tumble dryer can use anywhere from 3,000 to 5,000 watts of power, and some models can use even more than that. To give you an idea of how much this is, a typical modern light bulb uses only about 10-15 watts of power, so running even a more efficient tumble dryer for an hour would use as much energy as 300-350 LED light bulbs! As a general rule of thumb, you can expect to pay about £1.25 per load to run a tumble dryer in the UK at current prices, however, you guessed it, this will vary depending on a range of factors including the size and efficiency of the model, how full the dryer is and the cost of electricity in your area.

If, in the winter, you struggle to dry clothes without using your tumble dryer, there are a few things you can do to make sure it’s operating efficiently:

  • Clean the lint filter before and after each use. A clogged filter can reduce the dryer’s efficiency and even cause a fire hazard.
  • Avoid overloading the dryer. Clothes need room to tumble and circulate air in order to dry efficiently.
  • Use the moisture sensor setting, if your dryer has one, to help prevent over-drying and save energy.

Air drying

If weather allows and you have outdoor space, drying clothes in the open air is a quick, zero-cost solution. Given the nature of UK weather though, drying clothes indoors at some point is unavoidable. If possible, use a drying rack in a well-ventilated room – ideally in a room that will receive plenty of sunlight. Ventilation is essential to prevent mould and speed up drying – but if you have to open a window in that room, try to make sure airflow between that room and the rest of the home is minimalised (using draught excluders for example).

To further speed up the drying process and address ventilation issues without needing to open windows, you could use a dehumidifier, which removes excess moisture from the air and costs less to run than a tumble dryer. It can also be tempting to resort to drying clothes on radiators, but this may cause damp issues over time and will negatively impact your heating efficiency. Never dry clothes on electric heaters as this poses a significant fire risk.


The exact amount of energy any device uses can vary depending on its size, age, and efficiency rating, but the fridge is generally one of the largest energy users in the home. A typical C rated energy efficiency refrigerator will use 150-200 kWh of electricity per year, which at October 2022 price cap levels would cost a home between £60-£70 per year. However, an older fridge with an F rating may cost you double that amount. 

Even if you’ve got an older, less efficient fridge, there are ways to make sure it runs efficiently:

  • Make sure the fridge is properly sealed and doesn’t have any gaps or leaks where cold air can escape. This will help the fridge maintain the right temperature and use less energy.
  • Set the fridge to the right temperature. The optimal temperature for a fridge is between 2 and 4 degrees Celsius. This is cold enough to keep food fresh and safe to eat, but not so cold that the fridge has to work harder to maintain the temperature. Changing a standard fridge by 1 degree will impact its running cost by 3-4%.
  • Avoid putting hot food directly into the fridge. This can cause the fridge to work harder to cool the food down, which can waste energy. Let hot food cool to room temperature before putting it in the fridge.
  • Minimise the number of times you open the fridge. Every time you open the fridge, cold air escapes and the fridge has to work harder to maintain the right temperature. 


Like fridges, ovens can be big energy guzzlers if used frequently. For perspective, a typical electric oven will use about 0.89 kWh of electricity per use, while a gas oven will use 1.5 kWh. At current prices, that means a gas oven is about half as expensive to run as an electric oven (due to gas costing around a third of the price of electricity per unit of energy).

To use an oven more efficiently, there are a few things you can do:

  • Avoid opening the oven door unnecessarily. Every time you open the oven door, heat escapes and the oven has to work harder to maintain the right temperature. Try to resist the temptation to open the door to check on your food, and use a timer or the oven’s light instead.
  • Consider using the oven’s fan setting if it has one. Fan-assisted ovens circulate hot air around the cooking space, which cooks food more quickly and evenly while using less energy.
  • Use the right oven temperature. The optimal oven temperature will vary depending on the type of food you’re cooking, but in general, it’s better to cook at a lower temperature for a longer time than to cook at a higher temperature for a shorter time.

Should I unplug my phone charger?

When you’re not using your electronic devices and appliances, they may still be using electricity – even when they’re turned off. This is called ‘vampire power’, because it’s as though they’re secretly sucking energy from your home. The main culprits are your broadband router, wi-fi range extender, games consoles, set-top boxes, computers, televisions and printers.

Most modern appliances have very effective ‘sleep’ modes, which reduce power consumption to almost zero, but it’s important to make sure they’re used properly. For instance, leaving a set-top box running at all times rather than putting it into sleep mode will cost up to £70 a year at October 2022 price cap levels. Leaving your computer active rather than putting it to sleep could cost as much as £60.55 a year.

One thing to watch out for is turning off your broadband router too regularly. Given that keeping them can cost you between £12-£60 per year, it could be tempting to turn it off. However, if your home regularly disconnects due to turning off the router every night, your internet service provider may mistakenly think there is a problem and slow down your internet speeds while you’re using it, so that they can guarantee a consistent service.

There are also some appliances that aren’t worth unplugging, like phone chargers, because the total cost to keep them running is minimal. For more information on standby energy usage, see our 7 tips to reduce your energy consumption at home.

What other help can I get with my energy bills?

Citizens Advice has a great article that summarises the government support available. Although recent weather has been unseasonably mild, the government awards £25 payments for every 7 days your area is recorded as, or forecast to be, zero degrees Celsius or below, so you should check your eligibility when the next cold snap hits.

[1] Based on this government data – Excel file