How to survive heatwaves as electricity bills explode without breaking the bank

With temperatures climbing and electricity bills spiralling, here’s how to get through heatwaves without spending a fortune.

It’s sweltering in France right now, and it’s unlikely to get any easier as summer goes on. When you’re struggling in the heat, it can be tempting to leave your shutters slightly open during the day to try to create a breeze.

As Futura Science points out, that’s clearly not the right move, because shutters are crucial during a heatwave:

"This external protection is particularly important, because once the sun’s rays pass through the windows, they warm the walls, floors and furniture. The heat that builds up then becomes trapped indoors, creating what is known as a domestic greenhouse effect."

So when the temperature outside is higher than indoors, you should not leave any gaps open during the day.

The most effective weapon: natural ventilation

Once the outside air cools down again, ventilation is the cheapest and most effective defence against overheating. The method is straightforward: open your windows wide when it’s cool (usually at night), then close them again before temperatures rise.

If you create a proper cross-breeze, you can bring the indoor temperature down without paying a penny.

After that, the goal is simply to hold on to the cooler air throughout the day by closing every window, shutter and curtain, so they act as a barrier against direct sunlight. Yes, your home will feel darker than you’d like, but at least it won’t be 30° in a poorly insulated flat-and you won’t be burning through electricity with air conditioning running at full power.

You can also use a fan, which is incredibly effective if you set it up properly. In the evening, place it in front of an open window so it pulls in the outdoor air as it starts to cool. The insider trick? Put a container of very cold water in front of the blades.

Evaporation can turn a basic, low-cost desk fan into a DIY air conditioner. You’ll feel the cooling effect right away, and it’s worth remembering that a fan’s electricity use is more than 10 times lower than a portable air conditioner.

There’s also the wet-sheet approach, long used in traditional Maghreb architecture. Damp fabrics are hung where air moves through the home to cool the atmosphere. The modern version is to soak an old sheet in cold water, wring it out slightly, and hang it in front of an open window. As the water evaporates, it draws heat from the incoming air and can reduce the temperature by 4 degrees.

Barricade your home against the sun

If you’re in a pinch and have very little to spend, aluminium foil could genuinely help. With the shiny side facing outwards on any sun-facing panes, your windows effectively become reflective mirrors.

This costs next to nothing compared with professional solar films that can be sold for a small fortune. That said, the best approach is still to close your shutters and curtains before the sun returns, after you’ve aired the place with cooler night-time air.

Hunt down hidden sources of heat

Everyday electrical devices can act like heaters in disguise. A laptop can give off as much heat as a 150 watts radiator, and internet routers also release a steady, often unnoticed warmth. During the hottest spells, unplugging anything non-essential can noticeably reduce the temperature in a room. So don’t hesitate to switch off and unplug gear you’re not using-the electricity savings will be even greater.

Be mindful too of halogen bulbs, which convert a lot of electricity into heat. Modern LEDs use ten times less power and produce negligible heat.

It’s also easy to overlook, but cooking becomes a major issue during a heatwave. An oven can turn any home into a sauna, and hobs throw out intense heat. The most effective plan is to cook very early in the morning while temperatures are still bearable, then lean towards cold meals-salads and gazpachos that don’t require any cooking at all.

Shift your routine like people in hot countries

Mediterranean communities have spent centuries developing habits suited to extreme heat. Their key tactic? Completely reshaping the daily timetable to avoid the hottest hours. Get up at 6 h to take advantage of the morning cool, take a siesta from 14 h to 16 h when temperatures peak, then pick things up again later as the sun drops.

When you rest, your body generates far less heat and uses less energy. The Mediterranean siesta lines up precisely with the hours when outdoor temperatures hit their highest levels. Of course, it depends on your working situation, but it’s a sensible way to adjust your summer routine.

Choose your clothing strategically

Fabric choice directly affects how hot you feel. Polyester and other synthetics trap sweat and create a greenhouse effect on the skin. By contrast, linen, cotton and bamboo let the skin breathe and support natural evaporation.

Colour matters too. Light shades reflect sunlight, while dark colours absorb it and convert it into heat. Wearing a black T-shirt at 35 °C effectively turns you into a walking radiator.

The chilled-laundry trick can provide instant relief: put sheets, T-shirts and underwear in the fridge for thirty minutes before wearing or using them. That sudden coolness against the skin temporarily offsets the ambient heat and makes peak temperatures easier to tolerate. Otherwise, there’s always Sony’s personal air-conditioning device, though it isn’t cheap.

Turn your nights into a refuge

Heatwave nights call for a stripped-back sleep setup. Duvets and blankets should be replaced with a simple linen or cotton sheet. These natural fibres move moisture away from the body better than synthetics. In extreme cases, sleeping directly on the mattress avoids extra layers of fabric.

A chilled pillow can work wonders for heat-related insomnia. Put it in the freezer for an hour before bed to create a pocket of cool that lasts for several hours. This makes it possible to fall asleep even when night-time temperatures exceed 25 °C, and it doesn’t cost much.

A hot-water bottle in summer sounds ridiculous, right? Yet a frozen hot-water bottle filled with cold water and left in the freezer for two hours will release coolness into the bed for hours. The gradual cooling supports falling asleep without a sudden thermal shock.

In summer, hydration is essential

Hydrating in high heat comes with a few counter-intuitive rules. Iced drinks, tempting as they are, don’t hydrate as well as lukewarm liquids. They can cause thermal shock that interferes with the body’s temperature regulation. Mint herbal teas or cucumber-infused water, drunk at room temperature, tend to cool you for longer.

It’s frequency that matters more than volume. Taking small sips very regularly improves absorption. The body handles a steady intake better than occasional large amounts. This approach helps keep hydration stable, even in extreme heat.

Food also plays an active role in cooling you down. Watermelon, cucumber, tomato and courgette contain over 90% water, making them ideal alongside drinks. These water-rich foods cool you from the inside while also helping replace mineral salts lost through sweating.

Spend smart without overspending

A few affordable items can dramatically improve comfort. An electric misting fan at 35 euros combines airflow with water evaporation to create a natural cooling effect. As long as you keep it close-because it won’t cool a large space-it provides immediate relief.

A fan uses 50 watts compared with 2000 watts for a portable air conditioner. Over three months of heavy use, the electricity saving exceeds the 200 euros mark. And for remote workers or anyone stuck in an office where colleagues argue over the thermostat, the best option is often a small desk fan.

With a personal fan, you can stay cooler all day while keeping power use particularly low. That’s it-you now have a full set of low-cost techniques to cool down.