What is Paris's district cooling system, and how does it use the Seine to cool buildings?

Paris's district cooling system is a 75-mile underground network of pipes operated by Fraicheur de Paris (part of Engie SA) that circulates chilled water from central plants to cool offices, malls, museums—including the Louvre—using a closed-loop system; it taps water from the Seine via heat exchangers to assist in chilling, then returns slightly warmer water to the river.

Why is Paris's district cooling system considered more environmentally friendly than conventional air conditioning, and what challenges is it facing during the current heatwave?

The system is said to use 50% less electricity than standalone air conditioning and cut emissions by half; however, during the current record-breaking heatwave, its chilling plants are operating round the clock amid huge demand and occasional power outages, sometimes preventing water from reaching its usual low temperature.

How Paris Is Using the Seine to Try to Keep Cool in Scorching Heat

Jun 28, 2026

Engie subsidiary Fraicheur de Paris is leveraging Seine water for district cooling to combat record heatwaves, aiming to triple connections by 2042 despite operational strains.

bloomberg

2026-06-28

How Paris Is Using the Seine to Try to Keep Cool in Scorching Heat

How Paris Is Using the Seine to Try to Keep Cool in Scorching Heat

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