Is air conditioning worth it in the UK?
UK summers are getting hotter. In July 2022 we experienced our first recorded temperature above 40°C and the number of days when the temperature exceeds a comfortable 28°C are growing. According to the UK Green Building Council, 55% of UK homes are already overheating during relatively cool summers. The obvious solution seems to be to install air conditioning, and AC use has increased by 90% over the past two years alone in the UK.
But is aircon the answer to your stuffy home? Find out how much it costs and whether it’s the best solution to your heat-related problems. If not, discover what cost-effective and energy-efficient alternatives are available to stay cool in summer.
How much does air conditioning cost in the UK?
The cost of air conditioning in the UK breaks down into three parts:
- Unit costs
- Installation costs
- Annual running costs, including electricity consumption and annual maintenance.
Air conditioning unit costs
There are three broad types of aircon systems you can buy:
- Portable units: these cost around £300-£800, and are designed for smaller rooms and renters who can’t make material changes to their home
- Split systems: these combine one or more indoor units with an outdoor compressor that vents the hot air outside. They typically cost £1,500-£3,500 for a single room system, or £3,500-£7,000 for a multi-room split system
- Central air conditioning (or ducted systems): these cost £5,000 upwards and are usually reserved for larger homes and new builds, where they can be incorporated into the design.
Air conditioning installation costs
Again, the cost depends on the type of unit being installed. Portable aircon units can be installed by yourself for free if you’re comfortable with fitting the air-tight window slide for venting. Split and ducted systems require professional installation, which can add around £1,500 to £3,000 to the total cost of the system depending on what’s fitted and if any extra work is required.
AC running costs
Fixed air conditioning units require regular maintenance to keep them in good working order. According to Checkatrade, the average cost of an annual, one-off aircon service is £70-£120 per unit. This includes a thorough clean of all major components and replacement of the AC refrigerant but doesn’t include the cost of any repairs should they be needed.
In addition, you’ll also need to pay for the electricity used by your AC system. The larger the unit, the higher its power rating (and therefore energy usage):
| Unit | Power rating | Cost per hour* | Best for |
|---|---|---|---|
| Portable unit | 0.75-1.5 kW | £0.20-£0.40 | Smaller spaces |
| Single-split system | 0.8-2.5 kW | £0.20-£0.65 | Individual rooms |
| Multi-split or ducted system | 1-5 kW | £0.25-£1.30 | Whole house systems |
*Based on the current Ofgem price cap of 26.35p per kWh
Some modern systems are more energy-efficient and so draw less power and cost less to run than a portable air conditioner running for the same amount of time. However, unless you have solar panels, running an AC has the potential to add a significant amount to your bill - anything from £20 to £80 a month depending on how often you use it.
Is air conditioning energy-efficient?
Compared to other forms of cooling, aircon isn’t energy-efficient, particularly when it’s run on its own. Passive forms of cooling, such as insulation, window blinds and shutters or awnings, cost nothing once they’re installed while the vast majority of fans, from portable evaporative coolers to ceiling and tower fans, consume less than 0.1 kWh. It should, however, be noted that fans make conditions more comfortable rather than reducing the ambient temperature.
However, in recent years, air conditioning units have embraced several technologies to make them more energy-efficient. These include:
- Inverter AC technology, which adjusts compressor speeds to meet demand, reducing power consumption by up to 40%
- Smart controls and AI systems to further optimise their use so they’re not running unnecessarily.
When shopping for aircon units, pay particular attention to its SEER rating. The higher this is, the more energy-efficient it is - look for ratings of 7+ to keep costs down.
It’s also worth noting that aircon units have an impact on the environment outside your home, because they’re designed to remove warm air from your home and ‘dump’ it outside. By reducing the temperature in your home, you’re increasing it outside by up to 5°C, making the streets hotter and exacerbating the effects of a warmer climate. In addition, aircon contributes around 3-4% of all global emissions.
Portable vs. fixed aircon systems
If you’ve decided to install air conditioning at home, what’s the best type to go for?
Pros and cons of portable units
Pros of portable aircon systems
- Cheaper to purchase
- Lower running costs
- Portable
- No permissions or installation required
Cons of portable aircon systems
- Can only cool a relatively small area
- Heavy and take up floor space
- Not as effective at cooling as fixed units
- Requires venting to avoid buildup of moisture
- Noisy
Pros and cons of fixed units
Pros of fixed units
- Can reduce indoor temperatures within minutes
- Quieter than portable units
- Can be wall or ceiling mounted
- Increasingly efficient to run
- Can remove excess humidity
Cons of fixed units
- High upfront cost
- Expensive to run
- Complex, expensive, disruptive installation
- May need planning permission
- Can have a negative environmental impact
- Can dry out the air
Smarter cooling alternatives
Running aircon systems are expensive and not particularly energy-efficient, particularly if you don’t implement other energy efficiency measures first. If your budget won’t stretch or you’re worried about their environmental impact, consider the following alternatives.
Heat pumps
Your heat pump offers year-round cooling as well as heating - and can deliver the same cooling capacity as a comparably sized AC system, although they’re not quite as effective, so will take longer to cool the house on extremely hot days. Find out more about them with our guides to air heat pumps and ground source heat pumps.
Ceiling fans
While ceiling fans don’t reduce the temperature on their own, the airflow generated can help you feel 2-4° C cooler. They’re designed to cool an entire room, making them particularly useful in bedrooms at night, with a power rating of just 30-80 W.
Floor or desktop fans
Both floor and desktop fans are portable, allowing you to place them where they have the best effect. Like ceiling fans, they draw very little power - typically 60 W or less, which means they cost under 2p per hour to run.
Bladeless fans
Bladeless fans are another low-cost alternative to AC systems, with a power draw comparable to floor and desktop fans - around 40-80 W. Their main advantages over other fans are:
- Bladeless design safer for children and animals
- Quieter
- Smoother airflow.
Portable evaporative coolers
If a fan doesn’t help in particularly hot weather, you may be able to cool your personal space with a portable evaporative cooler. These cost around £50-£150 and combine a fan with a water reservoir that can be used to cool the air in the immediate vicinity (add ice cubes or blocks to reduce the temperature further). They draw a similar amount of power to regular fans - under 100W - but also consume litres of water with just a few hours use, so bear that cost in mind.
Shading, ventilation, insulation and other passive cooling strategies
Perhaps the most effective - and certainly cost-effective in the long term - strategy for cooling your home is to invest in passive cooling. From insulating your home to fitting an awning or shutters to your south-facing windows, keeping the sun out of your rooms can make a real difference, with shaded rooms up to 5-10°C cooler than those exposed to sunlight. And unlike aircon, you may be eligible for financial assistance with installation costs.
When does aircon make sense?
Aircon systems are best used sparingly - during severe heatwaves or in properties that become uncomfortably hot during the summer, such as poorly ventilated homes or south-facing flats in towns and cities with little or no tree cover. By combining them with other passive and low-cost alternatives, AC systems can add an extra level of cooling on the hottest days without breaking the bank.
FAQs
Does aircon use a lot of electricity in the UK?
Aircon can add hundreds of pounds to your annual energy bill if used regularly - particularly in the current era of high energy prices. The actual amount depends on what type of air conditioning you install and how long it runs for.
In contrast, portable evaporative coolers and fans consume a fraction of the electricity - less than 0.1 kWh, and some as low as 20 watts (0.02 kWh). Passive technologies, such as insulation, blinds and awnings, cost nothing to run once installed.
The best solution is to combine all three types. Passive technologies help keep your home cooler, reducing the need for fans and air conditioning except during heatwaves, to reduce the impact on your energy bills.
How much does it cost to install air conditioning in a flat?
Portable air conditioning units usually cost nothing to install - you may need some DIY skills to fit the window slide or pay £350 to £650 should you require professional help. Fixed units cost more - a single-split system is likely to cost an additional £2,000, including labour. You may also need to pay for an upgrade to your electrical system - a further £400 to £700.
Are portable air conditioners any good?
Portable air conditioners are best suited for temporary use - for example, in rented accommodation - or in smaller spaces, such as top-floor flats. They’re cheaper to buy and install than fixed units, and can be moved from room to room, but are usually less effective, cost more to run than a single split unit system, are noisier and have a limited cooling range.
When purchasing, check the unit’s cooling capacity, measured in BTUs - the higher the better. Aim for 18,000 BTUs for the best results.
Do ceiling fans actually cool a room?
No. Ceiling fans create a wind chill effect that makes you feel colder when they’re running, but they don’t reduce the room temperature on their own. However, when used in conjunction with an open window, they can draw in colder air from outside to help cool the room more quickly.
Is aircon worth it compared to fans or better insulation?
While AC will undoubtedly cool the rooms in your home, there’s a hefty premium to pay in terms of upfront costs as well as ongoing maintenance and increased energy costs. If you’re struggling with hot rooms because of poor ventilation or insulation, then a more cost-effective (and environmentally conscious) solution is to explore energy efficiency measures such as better insulation, double-glazing and shading options such as blinds or shutters. Once in place, you may find cheaper options like ceiling fans and portable evaporative coolers are sufficient to keep your home feeling comfortable during heatwaves.
What’s the cheapest way to keep cool during summer?
There are numerous low-cost ways to help keep your home cool during hot days:
- Shade windows - fit awnings to south-facing windows, or simply close curtains, blinds or shutters
- Fit reflective film to windows - you can get this from your local DIY store or online
- Cross-ventilate - open windows or vents on opposite sides of your home to allow fresh air to circulate. For best effect, use along the direction of the prevailing wind
- Switch off appliances - running appliances generate heat, so turn off any you don’t need
- Open sash windows - make sure you open sash windows at both top and bottom, so cooler air is drawn in at the bottom and hot air expelled from the top. Do this on north-facing windows
- Use fans or portable evaporative coolers - these are much cheaper to run than AC.
For more cooling tips, check our energy-saving tips to cool your home in summer.
