Built from scratch and inaugurated in 2024, the arrivals terminal of Roland Garros airport on the island of Réunion, near Madagascar, has a peculiarity: despite being in a tropical area south of the equator, it has no air conditioning.
In the hottest and most humid months, from November to April, the 30°C outside becomes 25-26 inside thanks to a combination of huge ceiling fans and the particular structure of the roof, which allows outside air to enter, refreshing the environment.
The project is the fruit of the visionary mind of Marc Delanoë, head of the airport’s environment and energy team in 2016 and currently director of sustainable development. Ten years ago, at the dawn of the project, it was he who decided not to use air conditioning to cool the rooms of the new terminal: “I took on the responsibility of demonstrating to my management that not using air conditioning was feasible: a risky bet, but the more we studied the more we understood we were right”, he explains to the Guardian.
Wave roof and ceiling fans
The peculiarity of the building is the roof, which has a slightly wavy profile and is divided into two halves separated by a central crack, a sort of canyon which creates a low pressure area capable of drawing air inside.
The breeze then passes through the over 800 automated slat windows which can be adjusted based on the weather: during the hottest and most humid months the windows remain completely open and the trade winds, the constant winds in the area that blow from the east, manage to lower the internal temperature by 4-5 °C, bringing it to 25-26 °C; in winter, when the external climate is milder and drier, the intake of external air is reduced, while during a cyclone the entire building is completely closed. To contribute to the cooling there are some ceiling fans with a diameter of 7.5 meters.
Reduced costs and emissions
The construction of the building cost 60 million euros: since its opening the airport has saved 150,000 euros a year in electricity bills, a 60% reduction compared to buildings with air conditioning. There have also been positive impacts on the environment, with CO2 emissions eight times lower than an air-conditioned building.
And in Europe?
The terminal on the island of Reunion is a virtuous example of sustainable architecture, which however cannot be replicated everywhere: the island has a tropical climate, but in the summer months temperatures generally fluctuate between 23 and 30 °C – a far cry from the 40 °C recorded in Europe in recent summers.
The trade winds also blow on the island, constant winds that allow the air to recirculate in closed buildings. In addition to this, we must take into account the pollution, which does not exist on the French island but is very present in the large cities of the Old Continent: “All the pollutants would be concentrated inside, it cannot work”, comments Delanoë.
According to Delanoë, however, we Europeans should also give up air conditioning and take advantage of natural ventilation: it’s a question (at least in part) of accustoming the body to “bearing” heat. It is clear that if it is 20°C at home and in the car, getting to an office where it is 28°C will be a problem. But if we learn to reduce the use of air conditioning, we will suffer less from the heat. However, an objective limit remains: with temperatures reaching or exceeding 40°C, as has happened more and more often in recent European summers, natural ventilation alone will hardly be enough to keep us cool.
