UK Power Networks trials Thermify’s HeatHub boilers, swapping gas flames for clustered compute
Reusing heat from servers has gained momentum recent years, but UK Power Networks (UKPN) is taking an unusual approach: installing mini datacenters powered by Raspberry Pi hardware in customers homes to provide heating for families struggling with energy costs.
UKPN, which manages the “last mile” of cables and substations delivering electricity from the National Grid to customers in the South East of England, is piloting the project as part of its SHIELD (Smart Heat and Intelligent Energy in Low-income Districts) program.
This will equip participating households with solar and battery systems, while one-third will also receive the “HeatHub” system - a compact datacenter roughly the size of a large heat pump that replaces traditional gas boilers. […]
I’ve often thought about this, if you’re actually using the waste heat from a PC does that mean its basically 100% energy efficient?
This seems like a really cool idea, although I’m not quite sure what happens in the summer when all this compute power gets shut off
Yes, a computer heating system would be just as efficient as an electric wall heater at near 100% effective whereas heat pumps effectively ranges from 300% to 500%: for 1w used to operate the pump you will pump 3 to 5w of heat into your home.
Well sure, if the electricity is powering something you already need and the waste heat is beneficial, then awesome, I guess that’s free heat. But it’s actually pretty rare that people need to be using that much electricity for anything as consistently as you would need for heating a home. And if you don’t actually need to be using that electricity, there’s really no way around the fact that electric heating is really pretty expensive.
I guess if you are stuck with electric heating as your only option and a heat pump is out of your price range, then mining crypto could be a nice way to offset the cost of electric heating… But then the equipment costs would add up and you’d probably be better off with a heat pump anyway.
My gaming PC noticeably helps heat up one of the rooms in my place during Winter.
In the Summer, however, that’s a downside rather than an upside.
Yes, but there is a big caveat: Heat pumps are much greater than 100% electrically efficient.
No, that doesn’t violate thermodynamics. We don’t count any of the thermal energy input into the “source” side of the heat pump, but it ends up on the “sink” side anyway. We are only comparing electrical input to thermal output, and the thermal output is much greater than the electrical input: Heat pumps are much more electrically efficient at heating your home than any form of resistive heating, including the waste heat from your PC.
A mining rig might be able to exceed the economic efficiency of a heatpump, but we would need much more data to attempt that calculation.
I’m not knocking this idea, but it seems like a common misconception that all heating is just waste. A heat pump, for example, gives more heat per unit of energy than just the basic one to one of resistant heating.
True but I guess the idea with this is we’re going to use servers anyway, might as well make use of the heat
It is solid logic, as long as you’re only utilizing heat that would have been produced anyway, independent of whether it’s used productively or not. It goes bad if you start justifying inefficient hardware for longer than you otherwise would have because of it.
100% efficient electric resistance heating (including computing) is somewhere around 1/5 to 1/3 as efficient as a heat pump. It’s also not necessarily better than gas heating, although that’s harder to directly compare.
But the heat pump doesn’t compute in parallel to heating.
Oh wow I didn’t know heatpumps were that much better
Yeah, depending on the heatpump, the outdoor temperature, and the target temperature, a heatpump can reach up to 5.5x heat output. That means for every 1 kWh of electricity you use to run the pump, the pump will output 5.5 kWh of heat energy.
Bitcoin bros actually did this at one point by making a space heater that was also a Bitcoin miner.
You get heat at similar energy efficiency to just running a regular space heater, but it pays back part of the energy bill with Bitcoin it mines. You could see how this could probably be adapted to other things, like what’s mentioned in the article (distributed cloud compute).
The main issue is that space heaters and other in-home heat generation units are still infinitely less efficient than things like heat pumps in many circumstances, since those can reach over 100% efficiency since they only transfer heat, rather than having to generate it from scratch.
I’m not sure I’d say infinitely less efficient. It’s a 5-6x difference, which is still very significant on the electric bill.
It is exactly as efficient as an electric heater, yes, but an electric heater is one of the least efficient ways to heat a home.
Most costly*
electric heating is very efficient in the sense that it converts almost 100% of the electric energy into heat. But electricity is expensive.
I think the implied point of comparison is (edit: e.g.,) heat pumps, which are effectively more than 100% efficient (as mentioned elsewhere in the thread), making ~100% efficiency relatively inefficient by comparison.
You keep pointing this out, and it’s true that heat pumps are superior. But given the range of options for home heating I think “100%” is going to be among the most efficient.
For electric heating, you basically only have two options, heat pumps and resistive. Within just that comparison, 100% is the lower limit.
If you want to compare it to other types of heating, efficiency becomes much harder to measure, because the inputs can differ.
If you’re using electricity generated by burning fossil fuels it’s simple enough, but the “100% efficient” resistive heating loses again because you could just burn the same fossil fuels in your home to heat it directly which is much more efficient.
If you’re using renewable power, then “efficiency” kinda becomes meaningless because you’re using entirely different resources to produce the heat, so you can only try to abstract it by using either money or environmental impact per unit of heat as a stand-in. I don’t have the numbers on it right now so correct me if I’m wrong, but I think resistive heating would actually be more expensive than fossil-fuel based heating, generally speaking - there’s a reason that it’s not really a wide-spread thing for heating whole homes.
So unless I’m wrong on something here, resistive heating is really not going to be among the most efficient options, unless you specifically only look at environmental impact and are using regenerative sources for it. But even then, the heat pump just wins by miles.
I dont need heating on weekends where i game a lot, so yeah this absolutely works. If your PC pulls 500W from the wall then its exactly like having a 500W space heater. Thats also why i play less compute intensive games during the summer or lock them to 60fps. Playing Palworld on 60 instead of 144Hz makes a roughly 100W difference for me.
its why i was jokingly saying back during covid winter, that at the time, while frowned upon, gpu mining is less wasteful than heaters. one heats a room something in return. the other intentionally wastes energy only to heat a room.
I thought the same thing, jjst in a different way:
If thr only thing electronics are 100% efficient at is producing heat, then why not think of a Raspberry Pi as a heater that just so happens to be able to do calculations as a byproduct, as opposed to heating elements which can’t?
Heat pumps are much more than 100% electrically efficient. They are around 300% electrically efficient.
Watt for watt, a heat pump sinks a lot more heat into your house than either a resistive heating element or a raspberry pi.