Are Air Conditioning Units Expensive to Run in the UK? (2025 Homeowner Guide)
Many UK homeowners are surprised to learn that air conditioning units aren’t as expensive to run as they think.
Based on the Ofgem electricity price cap (July–Sept 2025), a typical portable air conditioner costs around 26–32p per hour, while a wall-mounted split system is about 51–54p per hour – often less if you choose an energy-efficient inverter air conditioning unit.
This guide will break down UK AC running costs, show you how to save money, and explain why a professional installation from Domestic Heating can cut bills over the long term.
Table of Contents
What is the Real Cost of Running Air Conditioning Units in the UK?
Benefits of Installing a Modern Air Conditioning Unit at Home
What is the Real Cost of Running Air Conditioning Units in the UK?
The running cost depends on:
Wattage of your air conditioning unit
Efficiency rating (EER or SEER)
UK electricity tariff (currently ~25.73p/kWh)
Example running costs:
| Type of AC Unit | Typical Power Usage | Cost Per Hour (2025) |
|---|---|---|
| Portable AC – 1,200W | 1.2 kW | ~31p |
| Split System AC – 2,000W | 2.0 kW | ~51p |
| Inverter Split AC – 1,500W avg load | 1.5 kW | ~39p |
💡 Tip: An efficient split system can keep you cool for less than £1 per hot day.
How to Calculate Your AC Running Costs Per Hour
Formula:
(Wattage ÷ 1000) × Electricity price per kWh = Cost per hour
Example: 1,200W ÷ 1000 × £0.2573 = £0.31/hour
We can calculate this for your exact home setup during our free assessment.
Benefits of Installing a Modern Air Conditioning Unit at Home
Affordable running costs with inverter tech
Year-round comfort – many models also heat
Cleaner, healthier indoor air
Removes excess humidity
Quieter operation than older systems
Smartphone control from anywhere
Better sleep in warm weather
Increases property value
Cool only the rooms you use (zoning)
Lower bills with a professionally sized system
Top Tips to Reduce Air Conditioning Running Costs
Set temperature to 22–24°C
Use blinds or curtains to block direct sun
Seal gaps around doors and windows
Service your AC annually
Switch to fan mode on cooler evenings
What is the Difference Between Portable and Split AC Units?
Portable AC: Cheaper upfront, lower efficiency, needs venting, noisier.
Split System AC: Higher efficiency, quieter, long-term savings, adds home value.
For Hertfordshire homeowners, a split system from Domestic Heating is often the most cost-effective choice.
How to Choose the Right Size Air Conditioner for Your Home
We look at:
Room dimensions & ceiling height
Sun exposure
Insulation level
Room usage patterns
Correct sizing prevents wasted electricity and high bills.
Benefits of Inverter Air Conditioning Technology in the UK
Inverter systems adjust compressor speed to match cooling demand, reducing energy use by up to 40% compared to non-inverter models.
Emerging Trends in Air Conditioning for 2025
Smart energy tracking to monitor real-time costs
AI climate control that learns your habits
New eco-friendly refrigerants
Solar-compatible AC units
FAQs About Air Conditioning Unit Running Costs
Is AC cheaper to run at night in the UK?
Yes, if you have off-peak electricity or cooler night air.
Do air conditioning units need regular servicing?
Yes – to maintain efficiency and low running costs.
Will installing AC increase my property value?
Yes – AC is becoming a sought-after home feature.
How much does AC installation cost?
It depends on your property and chosen system – we offer free quotes.
Why Choose Domestic Heating for Your Air Conditioning Installation
Expert advice on efficiency and cost savings
F-Gas certified engineers
Full aftercare and servicing
Local Kent-based installers with fast response
📞 Call us today or visit Domestic Heating – Air Conditioning to arrange your free home assessment.
