Any home can benefit from an air conditioning unit. Summer in the UK can get hot, sometimes characterised by searing heat waves, leaving us feeling hot, sweaty, and sticky. Also, some homes tend to be warmer than others, and such homes will benefit from regular cooling with a suitable air conditioner all year.

Since we will be cooling our homes frequently in summer, it makes sense to find the most cost-effective cooling solution on the market. The big question is: What will be the air con running costs when choosing between conventional cooling systems and portable air conditioners? Let's dive deeper and focus on air conditioning for the UK:

Do you have more electrical devices and need to reduce your energy cost? Read our detailed post with 10 tips on how to reduce costs with an appliance-running cost calculator for the UK

How much does air conditioning cost to run UK?

Would it be cheap to run aircon units that are portable, or should you stick to conventional AC? Let’s find out.

When determining the cost of running a central air cooling system, one has to consider three things:

● Buying and installation costs

● Operating costs

● Cost of Maintenance

Cost of buying and installing an AC

How much you spend on a centralised cooling system depends on the unit's cooling capacity and the number of rooms you want to cool. If you have been shopping for AC, you probably have heard of single-room or whole-house ACs.

Single Room/Split AC

Single-room AC, as the name suggests, provides cooling in one room. The most common type of single-room ACs is the split AC system. They are called split because they consist of an indoor unit that absorbs heat from the room and an outdoor unit that pumps cold air into the room.

These two units are connected using insulated pipes that are passed through a hole drilled through walls.

Split ACs come in various sizes depending on how much energy they use to cool a room, often measured in BTUs. A small split AC unit rated 6000 BTUs is ideal for small rooms that are no bigger than 250 sq ft.

Expect to spend between £500 and  £1500 for a split AC that will be used in one room. A double-room split AC will cost roughly £1500 and  £2500 to install, while a multi-room split AC can cost as much as  £5000 to install.

Centralised or ducted AC units

Ducted ACs comprise a fixed AC unit that pumps cool air to various parts of a home or office through ducts that are connected to all rooms. The central AC unit must have a large power capacity to efficiently cool an entire home. And as you guessed, they can be expensive to install, ranging between  £6000 and  £9000 for a fully functioning unit. 

Whoa! And we haven’t touched on the cost of operating and maintaining these units.

Operating costs

How much electricity does a split or ducted ac unit need to cool a room or house in an hour, day, week, or month? Let’s find out. 

Note that the aircon running cost calculator applied here uses the standard electricity tariff UK of  £0.24.5/kWh (for the period 1 April to 30 June 2024)

A split AC unit can use about 480 watts an hour to effectively cool a room. A centrally ducted air conditioner can use 5000 watts an hour to cool an entire home. 

Using the price rating of £0.27/kWh

Split AC running cost

480 watts/1000= = 0.48 kW

0.48kW x 1hour = 0.48 kWh

0.48 x 0.24 = 0.117p

It will cost 0.117p to leave a split AC unit running for an hour.

Central/Ducted AC running cost

5000 watts/ 1000 = 5 kW

5kW x 1h = 5 kWh

5 x 0.24 = £1.22 

A ducted AC will cost £1.22 to run for an hour

Aircon Running Cost Calculator Table (Hr to Month)

This is how much it costs you to run a split AC or a ducted AC in your home for an hour to a month. As you can see, ducted units can be expensive to run and will significantly increase your monthly energy bills. While split ACs are cost-effective for a single room, they can be pricey to run if they are installed in several rooms.

Wow! You can easily calculate the electricity running cost of any device using our calculator at the end of this article!

Cost of Maintenance

Like any electric appliance, split and ducted ACs are prone to wear and tear with repeated use. Every once a year, these AC units need servicing to ensure they continue running efficiently. Also, factor in the cost of replacing faulty components like leaking duct pipes or AC refrigerants. This can easily attract an extra £20 to £180 to service your AC each year.

Air con running cost for portable air cooler

A portable air conditioner does cost less to run and maintain compared to conventional cooling systems. Take, for instance, a 990w portable air conditioner that can be used in a 20㎡. Here is how much it will cost to run a portable AC in your home or office.

First, the portable AC comes fully assembled and can be used straight out of the box. There is no need for expensive duct pipes or to hire someone to professionally install the unit. Now let's calculate the cost of running the unit. 

Let's take a portable air conditioner using 990 watts of power.

990w/1000= 0.99kW

0.99kW x 1h = 0.99kWh

0.99 x 0.24 = 0.242p

It will cost 0.242p to run a portable air conditioner for an hour. This translates to £5.82 a day (24 hours) and £162.9 a month if used 24 hours a day, 7 days a week. Remember, this is a large portable air conditioner capable of cooling a room as large as 20㎡. And with its 9000 BTU capacity, it takes less time to cool a big room, which means less energy is used. 

This portable air cooler would be enough for cooling a garage, conservatory, kitchen, or small studio apartment. 

Although, from our calculations, a split AC may seem cheaper, you have to consider the hidden costs of running one. There is an installation cost, which you do not need with a portable AC. In addition, a split AC unit remains stationary in one room and only provides cooling in that room. A  portable air conditioner can be moved from room to room, which will be cheaper to run compared to installing a ducted air conditioning system. 

Advantages of portable air conditioners

The air con running costs for portable air conditioners are lower compared to split and ducted AC units. Here are more benefits of portable ACs that will convince you further.

Less noisy

Another huge advantage of portable ACs is their low-noise operation. They produce noises as low as 70 dB, which is less disruptive. You can leave the portable air conditioner running all day and it will not disrupt your conversations or agitate a sleeping toddler.

Do you need to buy a quiet portable air conditioning device? Read our comprehensive guide with tips for choosing the best quiet portable air conditioner

Easy installation

You do not need to hire an expert to install portable air conditioners. Most come fully assembled, and all you need to do is plug the unit into a power source and turn it on. You do not have to drill through walls to pass connecting pipes or install an expensive duct system to all the rooms in your house. Simply connect the window duct to easily drain water from the unit.

Compact design

Portable air conditioners have a slim design that will fit in any space. You can place them in corners when not in use and their aesthetic look will blend in with your decor. Since they stay on the ground, portable air conditioners do not block natural light from the window, unlike bulky mounted ACs that tend to take up window space.
 

Energy efficient

Portable AC units are more energy efficient compared to split or ducted air conditioners. A typical tower air cooler with a 9000 BTU capacity only uses 990 watts of energy to cool a room as large as 20㎡. Accordingly, a 7000 btu portable air conditioner uses 780 watts of energy and is ideal for 10–15 square metres. Moreover, portable ACs are better than split ACs because they can be centrally placed in a room for efficient air circulation, which means low power usage. 

Safe to use

Modern and stylish portable air conditioners now come with added safety features like an inbuilt child lock on the unit’s dashboard. This feature prevents a curious toddler from changing the settings on your AC while it runs.

Smart features

Having a portable AC with smart features makes it easy to remotely operate the unit for added efficiency. For instance, a compact air cooler with Wi-Fi allows you to monitor indoor temperatures, adjust fan speeds, or set running and standby times all with your smartphone. Smart features can help you run your portable air conditioner more efficiently and save on your monthly energy bills. 

Also, there are portable ac with in-built dehumidifiers. They cool a room by simultaneously filtering out hot air and humidity. Increased humidity can make hot weather feel more unbearable, and having a portable AC with an added dehumidifier comes in handy in such conditions.

Conclusion

How much does air conditioning cost to run UK? Well, it depends on whether you are going for modern or conventional cooling solutions. While conventional cooling options like split AC and ducted AC are effective in cooling, they do cost a lot to install, run, and maintain. Portable AC units are the future because they can be used straight from the box and come with smart features for added efficiency.
 

FAQs

Is air conditioning expensive to run?

Air con running costs depend on factors like the type and size of the AC, the size of the room to be cooled, and the cost of electricity. For example, a 9000 BTU ac using 900 watts of power can cost 0.22p to run in an hour, while a ducted air conditioner will cost £1.22 (according to the current standard electricity tariff UK (24.5p/kWh) from April 1 to June 30, 2024). In addition, the bigger the room, the more power and time it takes for an air conditioner to cool that room, which can increase energy bills.

How much does portable aircon cost to run?

A portable air conditioner continuously drawing 990 watts of power uses 0.24p of electricity to run in an hour. The same unit will cost £5.82 to run in a day and £174.64 per month to run (based on current UK electricity price (24.5p/kWh) (1 April–30 June 2024) if the appliance is constantly operating for 24 hours a day, 7 days a week. Most portable air conditioners come with added features, like inbuilt WiFi, which, when effectively used, can help drive air con running costs down.

How much does aircon cost to run onheat mode?

Air conditioners with an inbuilt heat pump can be used to warm a room on cold days. Ideally, a hot and cold AC consumes less power in heat mode compared to when it's in cooling mode. This should use less power, which means less energy costs when heating a room.