The environmental councilwoman of Levallois-Perret, Sophie Deschiens, traveled the world in search of the system, which uses a series of stainless steel plates attached to the bottom of sewer pipes to capture -- thanks to a special liquid -- heat, according to a report in Brazil's O Estado (translation).
Where does the heat come from? Mostly standard household activities, such as warm showers, dishwashers, or laundry machines. That drained water carries heat down the pipes -- so much so, in fact, that the city's pipes are a temperate 68 degrees Fahrenheit, or about 20 degrees Celsius.
Aware of a new aquatic center under construction in the town, Deschiens partnered with a local business to get the $650,000 project approved. By her calculations, it will pay for itself in 10 years' time -- and in the meantime, reduce the city's energy costs by 24 percent and its greenhouse gas emissions 66 percent.
Since 1989, the heating system of the city already received power generated from waste treatment. Now, captured heat from sewer pipes can keep the water of the town's pools, spas and jacuzzis to a toasty 85 degrees Fahrenheit.
With the system now operational in the midst of winter, that's surely a smart idea.