A ceiling of green and blue ribbons swaying in the wind, revealing here and there a few birds clinging to a fine net. An incessant ballet immortalized by many visitors who stop to film the scene. In Rennes, the colored ceiling of rue Le Bastard is the delight of social networks. Since its installation above the main shopping street in the city center, this shading device could not really be tested. The fault with a capricious weather, even abominable, which did not really give way to the heat. This Friday, the temperature exceeded 27 degrees in the center of Rennes. A heat certainly far from that felt in a large part of France but which should finally make it possible to test the effectiveness of the device intended to fight against heat islands. In this artery where it is impossible to plant trees, the city wanted to innovate by trusting the system imagined by the Portuguese collective of artists Impact Plan.
The thermometer goes down to the ground
To measure the impact of this colored roof, the city of Rennes has installed sensors. While waiting to know the first conclusions, 20 minutes conducted a first test on Friday. Under a rather cloudy sky, we recorded the temperature under the shading device and in the nearby town hall square. Result: 26.6 degrees under the roof and 26.9 degrees on the neighboring square. A small difference probably due to the cloudy veil which covered the sky of the Breton capital on Friday. But another piece of data is more convincing. By measuring the surface temperature on the ground, we recorded 27.4 degrees in the shade when the same granite showed 33.7 degrees a few meters away. These data are not sufficient to validate the effectiveness of the process but show its potential. By shading a very mineral street, the city can undoubtedly reduce the burning effect of floors that are usually chiselled by the sun.
The effectiveness of the sky of colors, Rose and her daughter were able to test it when the sun began to shine on Friday afternoon. “We immediately felt the difference. Probably a few degrees. We felt in the shade”, explain the two Vannetaises. “You especially feel the difference when you arrive from a very mineral place like the Place de la Mairie”, explains this trader from rue Le Bastard. After a month of testing the roof of ribbons, the latter is however struggling to deliver a verdict on their effectiveness: “The weather was so rotten that we couldn’t really test. On the other hand, I can tell you that it brings people here! We see people filming or photographing themselves in the street all the time. »
“It’s really shit”
He is telling the truth. On both sides of the street, many passers-by stop to photograph the novelty. “It’s really beautiful,” slips a woman, phone in hand. In Toulouse, a similar device has been installed but is more mocked by the inhabitants. It must be said that the density, width and color are more reminiscent of Christmas decorations than a shadow system.
In Rennes, if the tourists seem delighted with the show, some locals are annoyed. “To me, it’s really shit. We use plastic to provide shade in a street that only has sun for two hours a day,” asserts this young shopkeeper from rue Le Bastard. “It is useless when the weather is nice. And the days when it rains, it’s so dark it’s like November. His partner criticizes “the rain which still falls, even when it has stopped”. But the most recurring remark concerns more the material. “We want to make shade with plastic. There was probably better to do, ”regrets a passerby. The Rennes municipality specifies that the device is only a test. If it proves conclusive, other materials could be found. This 2023 version should remain on hold until the end of September.