Vancouver recovers waste heat from warm sewage

“In 2022, the local utility said it generated 23,441 megawatt hours of thermal energy from sewage water—enough to heat 3,000 residential apartments for a year.”

"To start, a liquid refrigerant is passed through an evaporator, turning it into a gas that’s funneled into pipes surrounded by wastewater. The gas absorbs the water’s heat and is then run through a compressor to make it even hotter—as high as 176°F (80°C). The hot gas is then circulated around pipes containing clean water. While that water flows through insulated distribution pipes to individual buildings, the gas reverts to its liquid form. Though heat pumps like these use some electricity, they are four times more efficient than boilers or electric heaters. "


This is like finding gold in the sewage. A growing number of cities worldwide are harnessing that warmth to generate power and heat municipal buildings, homes and apartments.

I remember when they started collecting methane gas at garbage dumps and generating electricity. Now nearly every garbage dump is collecting the methane.

1 Like

It seems that the common practice is to have a sewage fee on your local water bill. Maybe we should get paid for sending them the “warmth.”



Probably ought to put one of these recovery units near every taco shop and bar in the neighborhood.

1 Like