Summer Heatwave Survival Cost Calculator
Instantly estimate how much a summer heatwave could add to your household spending. A free tool to work out extra cooling electricity costs plus hydration and comfort spend over a hot spell.
Heatwave Cost Projection
Enter your cooling setup and household details to estimate the cost
How many days the heatwave is expected to last.
Used to work out the estimated cost per person.
Your main cooling appliance and its approximate power draw.
The average number of hours you expect to run it each day.
Your unit rate for electricity, shown on a recent energy bill.
Cold drinks, ice, sun cream and other heatwave essentials, per day.
Your Heatwave Cost Estimate
Extra electricity, hydration and total spend breakdown
Enter your cooling setup and household details above and click Calculate Survival Cost to reveal your heatwave cost projection.
Cooling Appliance Running Costs
Quickly reference the approximate power draw and hourly running cost of common cooling appliances, based on a typical electricity price of £0.27 per kWh.
| Appliance | Typical Power Draw | Approx. Cost Per Hour |
|---|---|---|
| Standing/Desk Fan | ~50W | ~£0.01 |
| Tower/Pedestal Fan | ~60W | ~£0.02 |
| Portable AC Unit | ~1.2kW | ~£0.32 |
| Split-System AC | ~1.5kW | ~£0.41 |
Heatwave Cost FAQ
Everything you need to know about the real cost of staying cool during a heatwave, from electricity use to everyday extras.
It depends on the unit and how long it runs, but a typical portable air conditioning unit uses around 1 to 1.5 kilowatts of electricity per hour. Run for several hours a day over a two-week heatwave, this can add a noticeable amount to a household’s electricity bill compared to using fans alone.
Fans are almost always cheaper to run than air conditioning units, since a typical fan uses a fraction of the electricity of a portable or split-system AC unit. Fans cool people rather than rooms, so they are efficient for personal comfort, while AC units cool the air itself at a higher energy cost.
Many households spend more on cold drinks, ice, sun protection, hydration products and sometimes takeaway food during hot weather, as cooking at home becomes less appealing. These smaller daily costs can add up across a prolonged heatwave alongside any extra cooling-related electricity use.
Closing curtains or blinds during the hottest part of the day, using fans instead of air conditioning where possible, ventilating in the early morning and evening when it’s cooler outside, and avoiding running heat-generating appliances like ovens can all help reduce the extra energy costs of a heatwave.
Support tends to focus on heating rather than cooling in the UK, but some local authorities and charities offer help to vulnerable households during extreme heat warnings. It’s worth checking with your local council or energy supplier, as availability and eligibility criteria vary and change over time.
UK heatwaves vary considerably, but the Met Office generally defines a heatwave as at least three consecutive days where daily maximum temperatures meet or exceed a location-specific threshold. Some periods of hot weather last less than a week, while others can persist for two weeks or more.