We are not going to say that this decision was taken in general indifference. But let’s be honest. In the midst of the series of measures taken by the city of Rennes to reduce its energy consumption and avoid a bill of 470 million dollars, the extinction of the facades of certain buildings seems to go unnoticed. “We have not had any feedback in this direction in any case. While on other equipment’. Séverine Tersinet has heard a lot about the reduction in heating in schools or the lowering of water temperatures in her swimming pools. Much less the extinction of the facades of the Town Hall, the opera or the Saint-Georges palace, the Saint-Melaine church or the Martenot halls. The head of the energy security maintenance department of the city of Rennes had nevertheless suggested this idea in June when she saw energy costs soar. But refutes any idea of plunging the Breton capital into darkness every evening. “We only identified buildings that were not equipped with LEDs,” she explains.
To accentuate the challenge for the teams, the Rennes municipality has chosen to take part in the Cube competition*, the French energy savings championship organized by the French Institute for the energy performance of buildings (Ifpeb). Ten buildings in Rennes took part. While waiting for the winners, which will be unveiled this Tuesday, December 13 in Paris, some buildings can legitimately hope to win a distinction. City Hall is one of them. Here, all the measures taken by the municipality have made it possible to reduce consumption by 25.8% in a few months! The extinction of exterior lighting is not the only explanation for this dazzling progress. “We mobilized all the agents around the issue of monitoring computers, printers, light. Every little bit counts.”
By turning off their screen during the lunch break, by limiting the lighting in the event of small crowds or by unplugging the fridge in the break room during the holidays, the 130 agents working in the majestic town hall have caused consumption to plummet. Without disrupting their daily lives. On the other side of the square, the sumptuous opera also had to resign itself to no longer lighting its rotunda, while turning off the air handling units (but not the VMC) in the evenings and on weekends. Result: nearly 20% savings.
Will the buildings regain their lighting?
Among the ten buildings identified by the municipality, not all have had the same performance. But on average, the decline consumption is estimated at 7%. Sufficiently convincing to be maintained over time. The question we immediately ask ourselves is whether our monuments will be lit again one day? “They will be able to when we have equipped them with LEDs”. With LEDs, facades will be even more beautiful.
* Competition for efficient building uses