[renhanxue]

Those are some big heatpumps, but in terms of installed capacity at a single location they have yet to beat the Stockholm municipal heating utility's installation at Hammarbyverket, which since its most recent expansion in 2013 has a total of 7 heat pumps capable of extracting up to 225 MW of heat energy from treated sewage. The utility claims it is (still) the world's largest heat pump installation. Notably it actually uses both the hot and the cold side of the heat pumps; the cold side is sent into the district cooling network.

[jabl]

Interesting. In Helsinki the municipal energy company has a plant with 7 heat pumps which is slightly smaller at 160 MW heat and 100 MW of cooling. https://www.helen.fi/en/news/2023/Waste-heat-plays-a-signifi...

[renhanxue]

Looks like the expansion to 300 MW will have Stockholm beat soon if it hasn't already happened! Or is that in a different plant? Wasn't entirely clear to me, but great progress nonetheless!

[fsckboy]

>energy from treated sewage

wouldn't untreated sewage, still fermenting, be warmer?

[renhanxue]

Maybe. I guess it's easier to handle in treated form though. At the point where it gets to the facility it's actually not really sewage anymore, it's just clean water, so after passing the heat pumps it's just released into a nearby lake via a small turbine (both the sewage treatment plant and the heating plant ar located above the water level of the lake).