“We are six in the family, we have a house of 200 square meters and, at the moment, we put the central thermostat at 15°C maximum”.

In the living room of Geoffrey Van Moeseke, in Louvain-la-Neuve, in central Belgium, the thermometer reads 14.5°C. Outside, the temperatures are negative. Despite the frost, which can be seen through the large bay windows of his living room, he assures that he does not feel the cold.

For the third consecutive year, the engineer is applying the principles of the SlowHeat project - "slow heating" - to his home, for which he is both a researcher and a guinea pig.

This research project, coordinated by the University of Louvain, involves four researchers and around twenty citizens.

The idea is simple: “Heat bodies, not walls”.

In other words, look for back-up solutions that allow local heating while spending much less energy than with central heating.

First reflex advocated by researchers? Adapt your wardrobe! “Currently, I wear a cotton sweater, quite classic, over which I have an old, fairly warm cardigan. Below, I still have two layers: a T-shirt and technical sports clothing, outdoors, which really brings quality, ”he explains.

For the feet, socks and “old stuffed slippers which are extremely warm”.

Second advice: favor electric radiant heaters. Geoffrey Van Moeseke owns two of them, which he lights for one to two hours a day: one in the living room, the other in his eldest son's bedroom, the coldest room in the house - the average temperature there exceeds rarely 12°C. This radiant panel - table placed on the desk - emits powerful heat quickly.

On their site, the researchers also recommend the electric heating cap whose purchase is “paid for in a month”, they assure. Facing the computer, some of them use heated mouse pads.

“We were taken for crazy”

Launched in September 2020, the SlowHeat project aimed to anticipate an energy crisis.

“We wondered what would happen if all of a sudden, we had no more gas,” explains Denis de Grave, research assistant at the University of Louvain.

“At the beginning, we were taken for crazy”, testifies Grégoire Wallenborn, researcher and teacher at the Free University of Brussels, bundled up in a big vest, cap screwed on his head and mittens in his hands. In his apartment in Brussels, the average temperature fluctuates between 12 and 14°C.

Two years later, inflation and war in Ukraine have driven up energy prices in Europe and the SlowHeat project is enjoying renewed interest.

While gas and electricity bills are only rising, Geoffrey Van Moeseke only pays, on average, 70 euros per month for heating.

Before testing their methods, the SlowHeat researchers had to convince their families.

"I brought the project little by little," says Geoffrey Van Moeseke. “It was more difficult the first winter than the second, which shows that there is a form of habit and adaptation that takes place over time”.

For his younger brother, Célestin, 11, a woolen sweater and shorts revealing his bare legs, the temperature is not a subject: "I know that the first winter was harsher, we were used to a warmer temperature, but there I got used to it completely. I think it's hot here,” he smiles.

Not an "injunction"

But this has not been the case everywhere. Fear of the cold, fear that neighbors or friends would no longer want to visit, fear of conflicts within the roommate or the household... "We had to overcome fears at the beginning", recognizes the researcher.

Some habits are more complicated than others to adopt, such as the pedal set installed under the desk, which allows you to stay in motion even while working.

And the approach sometimes arouses strong reactions. "Some see the project as an injunction to stay in poverty," regrets Geoffrey Van Moeseke.

The researchers readily acknowledge that their project is not a miracle solution that would apply to everyone, but defend the need to rethink our habits, our relationship to consumption, and therefore to energy.

“The objective is absolutely not to tell people: you are going to be cold. The idea is to keep the same level of comfort, but with a few degrees less”, explains Amélie Anciaux, sociologist at the University of Louvain and member of SlowHeat.