Canadian company International Wastewater Systems wants to use the heat from sewage systems under cities to create energy.

Researchers for the company have developed an innovative system that recycles the heat into a heat source, and developers have been seeing a quick return on investment once they've installed IWS's SHARC (sewage heat recovery).

IWS’ Sewage SHARC uses raw sewage as a medium to produce hot water, heat, and cooling for large residential and commercial buildings. The sewage is used before it gets to the plant, with all of the solids removed. It is put through a heat exchanger and utilized to produce 140°F water for domestic potable use.

Mueller said this process is 500% efficient; every dollar spent gets $5 worth of efficiency. The SHARC system will last for about 30 to 40 years, thereby becoming extremely valuable over its lifespan. In fact, he said buildings can recover the money spent on the systems in three to 10 years.

Watch this video from International Wastewater Systems to learn more about the process:

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