How Paris's Seine river keeps the Louvre cool in summer

Paris: As Paris braces for a heatwave this weekend, a little known network of underground pipes will be cooling the Louvre museum and other storied la...

Paris: As Paris braces for a heatwave this weekend, a little-known network of underground pipes will be cooling the Louvre museum and other storied landmarks using water from the Seine river.

Since 1991, the river water has been cooling more than 800 buildings via a humble but hard-working system that is still relatively under-utilised worldwide.

Paris boasts the largest such urban cooling network in Europe: 110 kilometres (68 miles) of subterranean pipes criss-crossing the City of Light, reducing its need for energy-guzzling air conditioning.

"It's like 'Batman'!" exclaimed a passer-by in the chic and touristy eighth arrondissement or district of Paris, as a manhole cover was removed to reveal a spiral staircase to the cooling network below.

The technology is not new: the headquarters of the United Nations in New York has been using water from the East River for cooling since the 1950s.