PARIS (AP) — The Mona Lisa can keep her famous enigmatic smile because she benefits from one of Paris’ best-kept secrets: an underground cooling system that helped the Louvre cope with the record-breaking sweltering heat. temperature across Europe.
The little-known network of “urban cold” winds unsuspectingly under the feet of Parisians at a depth of up to 30 meters (98 feet), pumping icy water through 89 kilometers (55 miles) of labyrinthine pipes, which are used to cool the air at more than 700 sites. The system, which uses electricity generated from renewable sources, is the largest in Europe – and runs 24 hours a day with a deafening noise completely inaudible above the ground.
The mayor of Paris has just signed an ambitious contract to triple the size of the network by 2042 to 252 kilometers (157 miles). This would make it the largest district cooling system in the world. The new contract aims to help the city both adapt to and combat the threat of global warming. Many parts of Europe reached 40 degrees Celsius (104 Fahrenheit) in July.
The city will expand the cooling network to hospitals, schools and subway stations over the next two decades. It’s unclear how operational the system will be by the time of the Paris Olympics in 2024, but it’s possible the systems will be in use at multiple Olympic venues.
Unbeknownst to millions of tourists, the pipes are currently cooling the most emblematic sites of the City of Light, such as the Louvre or the Quai Branly museum. It could even help cool the tempers of restless lawmakers as it is used to bring down temperatures in the National Assembly.
The system is run by joint venture Fraicheur de Paris – 85% owned by French energy company EDF and the rest by public transport operator RATP. Company officials tout its benefits for the entire French capital.
“If all (Parisian) buildings are equipped with autonomous installations (like air conditioning), this will gradually create a very significant urban heat island effect,” said Maggie Schelfhaut of Fraicheur de Paris, referring to the increase in heat in cities. due to less vegetation, which cools, and more urban infrastructure, which absorbs the sun’s rays.
But Schelfhaut said the network of pipes could make the whole of Paris one degree Celsius (1.8 Fahrenheit) cooler than if stand-alone facilities were installed throughout the city.
“One degree less in the city center is a lot,” she added.
Three of the 10 high-tech cooling sites are on the Seine and accessed by a retractable spiral staircase barely visible from street level – in something resembling the lair of the “Teenage Mutant Ninja Turtles”.
When the water from the Seine is cold enough, a machine captures it and uses it to cool the water in the system. The heat created as a by-product is returned to the Seine where it is absorbed. The chilled water is then pumped through the system’s pipes to its 730 Parisian customers.
The Paris cooling sites all use renewable energy sources such as wind turbines and solar panels. Four new solar power sites that will power this grid are also slated for construction. French officials see this energy independence as particularly important given the threat of Russia cutting off Europe’s energy supply..
Russian energy company Gazprom reduced the amount of natural gas flowing through a major pipeline on Wednesday. from Russia to Europe at 20% capacity. European nations rush to find alternatives amid fears that Russia could completely cut off gas exports – which are used for industry, to generate electricity and to cool homes – to try to gain political influence over the bloc.
The advantage of using a cooling system using renewable energies to operate is already felt by the sites that use them. The world’s most visited museum, the Louvre, has benefited from the network since the 1990s – with officials proud of its ecological, economic and art conservation benefits.
“This allows us to benefit from energy with a lower carbon footprint available all year round”, explains Laurent Le Guedart, director of Heritage at the Louvre. “The peculiarity of the Louvre Museum is that it must use ice water to properly preserve works of art and control humidity.”
The Louvre does not use air conditioning, and officials say the cooling also saves them much-needed floor space in the sprawling but cramped former palace, which houses 550,000 works of art.
Guedart said the system saves money given the rising cost of energy linked to the conflict in Ukraine. She operates in particular in the State Room of the Denon Pavilion where the Mona Lisa lives. Perhaps that is why drops of sweat never ran down the forehead painted by Leonardo da Vinci.
“The Louvre’s energy bill is around 10 million euros per year in 2021. We are trying to control this bill as much as possible, amid the obvious fluctuations and increases in energy costs,” said Le Guedart.
The system could save him millions by cushioning the blow as Russia continues to shake up the energy market.
Jade Le Deley in Paris contributed to it.
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