Over the summer when it was a decidedly more relevant topic, I wrote about solar swimming pool heating, a common method of keeping pool water comfortable while treading lightly on the environment and saving on energy bills.
The past couple of days, I keep stumbling across articles profiling Sophie Deschiens, environment councilwoman in the Paris suburb of Levallois-Perret and her unlikely, and at first thought, totally foul-seeming, alternative method of heating the swimming pools and jacuzzis in the town’s new aquatic center: hot sewage.
Although I don’t expect sewage to replace solar heating methods in most residential pools in the near future, it’s a fantastic concept and one that’s not as gross as it seems since the heat is exchanged passively not directly.
Deschiens oversaw the pricey ($650,000) installment of stainless steel plates attached to the town’s sewage pipes that trap heat — the pipes in town average a balmy 68° F — and transfer it to the water heating system at the aquatic center. Apparently, there’s enough unused energy in the town’s pipes to keep the water in the aquatic center at 85° F for an entire year. Deschiens believes the sewage pool heating system will cut city energy costs by 24 percent and pay for itself within a decade. Plus, greenhouse gas emissions will be cut by an impressive 66 percent.
Again, sewage heat and swimming don’t seem to be the most pleasant match but this innovative method of heat reuse seems to be catching on in applications outside of pool heating. One rather huge example: waste heat recaptured from sewers will heat the Olympic Village at this year’s Winter Games in Vancouver.