Since 2020, Meta’s hyperscale data center — spanning 50,000 square meters on an industrial estate on the edge of the city — has been pushing warm air generated by its servers into the district heating network under Odense. That heat is then dispersed through 100,000 households hooked up to the system, with Meta providing enough heat to cover roughly 11,000.
I think the Nordics is probably the only place capable of utilizing this system in the first place. It looks like they have a utility system that already centralizes heating for their communities. They basically have a hot water line that circulates through radiators located in all the buildings in the community. Facebook was able to hook their heat exchange to this system, so they didn’t have to build any real infrastructure.
I’m not really sure how efficient this solution is, it really depends if their centralized system is a closed or open system. The water Facebook is pumping out is only 80 degrees, and has to be heated up to 170 by the utility company for service.
The problem is that while these servers produce a large volume of heated air, the intensity of that heat is very low, making it hard to exploit or preserve for transfer.
Germany has this concept implemented in a lot of places, too.
Ironically this results in some problems now. For example the city Salzgitter (100k inhabitants) is heated by the local steel plant – which currently transitions towards green steel. Their transition also leads to a shut down of their blast furnaces, leaving the inhabitants of Salzgitter out of heating.
No idea what their plan is to replace it, though.
District heating in Denmark is a closed system. The heated water leaves the Combined Heat & Power plant (CHP) or an industry’s heat pump and runs towards the consumers. In radiators it flows through and you pay for the difference in heat in/out and for tap water/shower etc. you have a heat exchanger that heats up the normal cold water line. The now colder heated water then runs back to the CHPs where it gets reheated.
Denmark may be big on windmills but CHPs are actually another energy technology that’s widespread here.
Ahh, that’s what I was hoping for! I was afraid it might be an open system, making the additional heat exchange from the servers mainly a vanity/pr project… My expectations for sensible utility companies have been damaged by living in America.
But yeah, depending on how much heat has been dissipated by the end of its loop, utilizing the heat from the servers right before it gets to chp would significantly reduce the amount of energy needed to get the temp up to 170f.
I wish we could do something similar, but I guess it would be stealing someone’s freedom or something?
I think you get a surcharge if your out heat is too high, meaning your radiators are running so high that you aren’t utilising the heat effectively, so the end-of-loop water should be pretty cold. Another thing to keep in mind is that CHPs would still generate the waste heat from producing power, so it’s a pretty efficient loop.
Fun fact, the Facebook district heating project was actually a big talking point due to server farms producing much lower heat than what is needed in district heating. People were split on whether it would actually have enough of an impact. As an example, my heat comes partly from a cement factory, a waste incinerator and a CHP as well as minor oil-based emergency heat generators. The CHP is capable of producing all heat by itself and the cement factory and waste incinerator were enough when the CHP had a major breakdown last year during autumn. During winter oil-based heat generators might be turned on to supplement the network on very cold days but they’re expensive to run, so they are only used a couple of days a year.
Other places don’t have central heating? Damn, I’ve always taken it for granted
Russia is another one big on central heating. I had to go there for work many times way before the war and their system was a nightmare. I was afraid I was going to freeze my ass off being in late-winter Moscow and instead, it was too hot everywhere. In the office they had to get a portable AC and in the house I stayed I turned down all the radiators in the room I slept and still had to sleep with the window slightly open.
Let’s just say I’m definitely not some Nordic person, quite the opposite but their system was whacked.
You see, their system could be heaven (it’s the same here). But we opt out for the lowest
Here the saying is, you feel cold, warm up. Not something Yanks take nicely haha
I think it could work for some college campuses too? I know there are a lot that use (used?) centralized steam heating and have a lot of that infastructure to pump the steam around still in place