Tiny data centre used to heat public swimming pool

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• Hacker News
• I don't understand how a server (the "washing-machine-sized datacenter") can heat up any fraction of a swimming pool appreciably. Wouldn't it be a few kW tops?
  by stavros
• And more importantly, once the pool is warm enough (or in a very hot day), doesn't it lose its cooling efficiency?
  by gravel7623
• No expert but I would think an indoor pool in a temperature controlled environment would control for a lot of heat loss from the water.
  by chucksta
• GPU power density is very high. The B300, for example, is rated at 1400W TDP. You can fit a lot of B300s in the space of a washing machine.
  by driverdan
• This washing machine sized box draws 50kW of power. It wouldn't be able to heat up a cold swimming pool very much, but it would be enough to keep a pool that's already hot at a stable temperature.
  by sushibowl
• You can fit, according to Nvidia, ~40 H100 GPUs in a 16U rack. That's 40 kW of power draw (and heat!) in roughly the space of a washing machine
  by swiftcoder
• Pre-GPU times you'd be right, but these days a 4U server could have 8 GPUs pulling 350+ watts each. A washing machine sized unit could contain perhaps 4 of these 4U servers so the unit as a whole could be drawing upwards of 11kW.
  by chippiewill
• Equinix AM3 provides heat to the Amsterdam Science Park.

  Undisclosed large Swiss private corporate datacenter provides heat to residential complexes in the surrounding area, as well as being integrated with the grid operator and required to spin up generators and island itself on demand, as part of the license to operate.

  Many such cases!

  by theodric
• > "Sean Day, who runs the leisure centre, said he had been expecting its energy bills to rise by £100,000 this year.

  "The partnership has really helped us reduce the costs of what has been astronomical over the last 12 months - our energy prices and gas prices have gone through the roof," he said.

  ...

  Last summer, BBC News revealed 65 swimming pools had closed since 2019, with rising energy costs cited as a significant reason."

  That's terrible that pools are closing. No one even builds new public swimming pools anymore, so it's awful to close the few that exist.

  by Schlagbohrer
• The date of the article is 2023.
  by khurs
• > Start-up Deep Green charges clients to use its computing power for artificial intelligence and machine learning.

  What about running the compute workloads of the municipality instead?

  by teeray
• I doubt the municipality needs 28kW of GPU compute, and certainly not at the prices someone like Deep Green is going to be charging.
  by avianlyric
• Bathhouse in New York wrote about this. Not sure they still do it to this day.

  https://help.abathhouse.com/hc/en-us/articles/16748674443924...

  by fjni
• France did one better...

  Paris 2024: Excess Data Center Heat Used to Warm Olympic Swimming Pools

  https://www.datacenterknowledge.com/sustainability/paris-202...

  by hnburnsy
• Providing remote heat is a common thing in Switzerland[1]. Just like Waste valorisation plants[2] that additionally produce electricity.

  [1] https://www.computerwoche.de/article/2690747/rechenzentrum-h...

  [2] https://stefan.schueller.net/posts/kva-winterthur/

  by sschueller
• Is it feasible to do this at smaller scales? Would be cool to use my compurers to heat water at home. Put all that useless heat to good use.

  Air conditioners could do it too, right? Pump heat into a water reservoir instead of just throwing it away?

  by matheusmoreira
• heata.co do precisely this with hot water tanks

  (I work there)

  by hkt
• Some people use cryptocurrency miners to heat their homes. It's certainly better than dumb resistive heating, but depending on various conditions it can cost more than installing a heat pump.
  by newpavlov
• I have connected the radiator of my homeserver liquid cooling setup to the heat exchanger of my hot water heat pump. Not sure how efficient it is, but I get a measurable drop in CPU temperatures while the heat pump runs.
  by thomas-skowron
• >Air conditioners could do it too, right?

  Some heat pumps do this. E.g. Panasonic Aquarea EcoFleX. When cooling the house, the domestic hot water tank is used to dump heat into (up to a certain temperature).

  by meindnoch
• > Is it feasible to do this at smaller scales?

  You need a lot of heat to do anything useful. I would need to run something like 14 kW of servers to heat my home through winter - that's a couple of hundred thousand in hardware at current prices.

  by swiftcoder
• Linus Tech Talk (LTT) did a whole series on doing this on the pool at the channel hosts’ house. Extravagant home upgrades are a frequent topic on that YouTube channel… business expense write off yada yada. My general takeaway was, yikes, all that piping and infrastructure would be a nightmare to maintain and will likely just be closed off whenever an issue comes up (or he sells). I’m no expert, but I am a home owner, and have come to form a deep appreciation for maintaining simplicity when it comes to the operation of your house.
  by arscan
• I have a pool heater and an air conditioner, and I'm running both at the same time. They're fifty feet apart, but this thought crosses my mind constantly.
  by RulerOf
• > The heat generated by a washing-machine-sized data centre is being used to heat a Devon public swimming pool.

  You mean server.

  by hahn-kev
• Eyeballing my washing machine leads me to believe they have a quarter rack or so.
  by hkt
• LinusTechTips did this at home. https://www.youtube.com/watch?v=d-4JJbk3ZS0
  by sjs382
• District heating is a mature technology. Direct Use geothermal heat is the one I am personally most familiar with -- as a geophysicist. However "waste" heat utilization is a definite thing for people with mechanical engineering/heat and mass transfer training.

  (Edited to add: there are several examples of public swimming pools being heated with Low T geothermal heat in the Perth metropolitan region of Western Australia.)

  by fghorow
• Here is a Swiss one that heats 6,000 apartments.

  https://d4project.org/

  > The data center delivers up to 1.7 MW of reusable heat – enough enough to warm 6,000 energy-efficient homes in winter or provide 20,000 five-minute showers every day in summer.

  https://blog.siemens.com/2026/05/sustainable-data-infomaniak...

  https://news.infomaniak.com/en/infomaniak-inaugurates-a-revo...

  by ano-ther
• In my home town the local steel plant has been connected to the district heating systems for half a century. This is extremely mature technology and widely used in parts of the world where heating homes is more important than cooling them.
  by designerarvid
• Something I have been wondering: Why don't data centres use the excess heat for a sort of energy recuperation, turning at least some of it back into electricity?
  by 9dev