The extra-degree trick: how much you’ll save by turning the thermostat down by 1°C

Cutting your heating bill doesn't always require making major investments or drastic changes to your home. Sometimes you can save by doing simple things, such as slightly adjusting the thermostat—lowering it by just 1°C. This adjustment may seem insignificant, but its impact on energy consumption is far greater than you might imagine—it can deliver between 5% and 10% annual savings, depending on the heating system and the property's insulation.

Why lowering the thermostat by 1°C makes such a difference

Heating is responsible for by far the largest energy expense in the home during the cold months. According to the OCU (Spain’s leading consumer organisation), heating the property can account for up to 70% of domestic energy consumption. That means any improvement in heating efficiency, however small, has a direct impact on your bill.

The reason why lowering the thermostat by 1°C saves so much is simple: the smaller the difference between indoor and outdoor temperatures, the less energy your system needs to maintain a feeling of comfort. That extra degree we sometimes turn up the thermostat ‘out of habit’ can send consumption up without providing any real increase in comfort.

How much can you save by lowering it by 1ºC?

Estimates may vary slightly by source, but they all fall within a very similar range. Energy-efficiency studies for homes put the saving at around 5–7%, while specialists in electric heating calculate it between 7–10%.

In practice, if your annual heating bill is between €600 and €800, lowering the thermostat by just 1°C can mean a noticeable saving without altering your routines. And if you decide to reduce it by 2°C, the impact on your bill is even greater.

The ideal temperature for an efficient home

There is no one temperature that suits every home, but there are recommended ranges based on thermal comfort studies. As a norm, you should keep it at around 19–20°C during the day in occupied rooms and reduce to 16–17°C at night or when nobody is home.

Most people feel comfortable within these margins, particularly when combined with suitable clothing and heat-retaining measures such as rugs, blankets or thermal curtains. For people who are more vulnerable to the cold—such as babies and elderly people—it may be necessary to raise the temperature slightly in their room, compensating by lowering it elsewhere in the home to maintain balance.

How to use the extra-degree trick without losing comfort

Lowering the thermostat by 1°C should be barely noticeable if you use other measures that help retain heat at home. Some of the most efficient include:

Programme the heating to suit your routine

Programming the heating to suit your routine is essential to avoid unnecessary consumption. Reducing the temperature at night or when the property is unoccupied helps the system work more efficiently and boosts savings when combined with wise thermostat use.

Prevent heat loss

Small draughts can make the heating work harder than it needs to. Check vulnerable spots such as:

• Poorly sealed windows.
• Exterior doors.
• Window blind boxes.
• Damaged or worn joints.

Good insulation helps to keep heat in and boost the effect of the extra degree.

Prioritise the rooms you actually use

Not every room needs to be the same temperature. If you spend most of your time in the living room or bedroom, set the heating so those areas are the most comfortable and avoid heating spaces you rarely use.

Wear appropriate clothing

Sometimes a light sweater or a blanket on the sofa can give you the warmth you need without turning up the thermostat. With small measures, 19°C can feel warmer without increasing consumption.

Keep the boiler or heat pump in good condition

A well-maintained system requires less energy to reach the desired temperature. Regular servicing is essential for efficient heating and for the extra-degree trick to ensure the best results.

The role of smart thermostats

Smart thermostats enable you to regulate the temperature much more precisely and adapt it to your daily routines. According to the OCU, their use helps avoid unnecessary consumption and maintain a feeling of comfort without needing to raise the thermostat.

Their main advantages include:

• They learn your routines to anticipate your needs.
• They automatically adjust the temperature according to the property’s actual use.
• They allow you to control the heating from your mobile phone, wherever you are.
• They detect open windows to prevent the system from continuing to run pointlessly.
• They provide consumption reports that help you understand and optimise expenditure.

If you want to get the most out of the extra-degree trick, a smart thermostat can become one of the most effective investments to improve your home's efficiency.

What if you lower it by more than 1°C?

The savings are proportional: reducing the thermostat by 2°C can lead to a notable reduction in consumption, provided the property is well insulated and the temperature is still comfortable.

Even so, it is not advisable to drop below 16°C for extended periods, as this can encourage damp and make the environment less comfortable.

The extra-degree trick: a small gesture with a big impact

Lowering the thermostat by 1°C is one change that requires no effort and is barely noticeable day to day, but it does make a difference to the bill. It is a simple, immediate measure available to all households, capable of reducing consumption without sacrificing comfort.

As we have seen, when combined with sensible programming, a smart thermostat and efficient habits, the effect is multiplied and the savings can be even more significant.