Why aren't all heaters computers?

Datacenter heat reuse is a thing. Mostly in European countries with cold climates. Notably, Finland has a few datacenters like that (Remov, Telia). I believe some countries might even mandate the feasibility study for reusing the heat for new datacenters.

I have no idea why it's not everywhere, but I see some issues right off the bat:

- you need a district heating system to dump the heat into, and to be really close to consumers

- the integration into the heating system isn't free

- heating supply doesn't match demand well (not seasonal; datacenter scaling depends on computing demand, heating is just a byproduct)

as a rule of thumb, electronics will take as much energy to produce as they will use in their lifetime. A silicon chip is a very expensive resistor which has already consumed enormous energy to produce (another rule of thumb, the cost of silicon is double the cost of the energy it took to produce)

disclaimer: i dont know where i heard this

also if you google "bitcoin miner radiator" there's a few attempts. Apparently there's a spa in NYC that heats their water with ASICs

https://kotaku.com/bathhouse-nyc-spa-bitcoin-asics-185095816...

The specifics of your question have an obvious answer: heat pumps are more efficient, and computers have a high upfront cost relative to their overall heat production, so we wouldn't have enough computers to meet heating demand.

The context of your question is a lot more interesting. Why don't we do something with waste heat? We already have systems to efficiently move it, so why not move it somewhere that it can be captured and put to use? If we were motivated enough to do that, could we?

There are a few realities that get in the way:

- Heat is difficult to trap, and difficult to move. You can't put heat on pause. That puts a hard limit on its travel distance.

- Computers have different distance limits. Sometimes, you want them to be close to each other; other times, you want them close to you. These two things are inversely correlated with the utility of heat production: You are likely to generate more heat from a computer that is near you, but unlikely to have any need to put more computers near it.

If you could game on a datacenter, then that would change this dynamic. If everyone on your block hosted a giant liquid-cooled LAN party, and used the heat to warm a pool...

The most efficient heater is a heat pump, and its not even close to heat generators.

We'd need two orders of magnitude more semiconductors than currently exist. We're already building them as fast as we can.

Global energy use for heating: ~150 trillion kWh/year

Waste heat from semiconductors: ~1 trillion kWh/year

Capital costs matter, especially for anything that's only run part-time. Buying servers that sit idle for half the year (during summer) would effectively mean they take twice as long to pay for themselves compared to servers that run all year. So that's at least twice as expensive.

Maybe the numbers would still work, but you have to actually do the math.

Well, our datacenter does use heat generated in server room to run heat pumps for our offices. Except there is much more heat in data center and we must still waste energy on cooling.

The premises nearby as far as I know were not much interested in harnessing this heat as that requires doing fair amount of infrastructure.

But I know that a nearby waste plant grows tomatoes and cucumbers by using electricity and heat from biogas (apparently when waste degrades it produces methane gas?!) - sorry for off-topic, just some green thinking went in my mind :)

Computers aren't free, if it costs even $1 to add a computer that generates enough heat (several hundred watts) to be useful as a heater...why not just omit the computer and make an extra dollar of profit, or charge less and undercut competitors that have computers?

Also consider the externalities...making unnecessary computers contributes to e-waste, it increases demand for rare-earth metals that are often mined in extraordinarily bad conditions (slavery and child labor)...

All this for what benefit? Is there a market of people that want to use a computer attached to a space heater? What useful thing is this computer going to do? Maybe it makes sense as a wi-fi repeater or something, but once again as the manufacturer what's easier/cheaper/simpler to design - a computer that generates heat and does some useful software task, or a fat 1500 Watt resistor that converts DC current directly into heat?

All that said, you might be on to something. With some clever advertising and marketing promotionals, I bet you can convert some portion of the space heater market into "premium" users of this contraption, all while make them feel eco-friendly through a greenwashing campaign.

So my answer is, this product doesn't exist for lack of technical creativity - it exists because the advertising industry hasn't sunk to such depths as to market this product yet.

Qarnot, a french startup is selling water heater, and space heater, and are used in some new building in France, and even swimming pools. They also sell cloud services, and market themselves as low carbon compute.

I find the water heater a smart thing, since you also need hot water in summer.

https://qarnot.com/en

Generally you only want heat for half a year, the other half you want it cool (roughly). In the half where you want it cool you then have extra load by the miner generating extra heat... or you turn it off, which seems like a massive waste of compute power.

There was a company in the Netherlands, can't seem to find the name right now, that rented out GPU clusters as central heaters, while using the GPUs to mine crypto. I believe they went backrupt during the whole crypto crash and energy crisis.

You can heat your home with bitcoin mining rigs: https://hackaday.com/2023/05/13/home-heating-with-bitcoin-mi...

Previous discussion: https://news.ycombinator.com/item?id=35934465

"Space Heater Offers 50% Cash Back On Heating By Training AI In Your Home"

https://www.forbes.com/sites/johnkoetsier/2023/12/09/space-h...

> A Bitcoin miner is more expensive to produce and maintain, yes, but over its lifetime shouldn't it pay for itself?

IIUC based on other news on HN, Bitcoin mining is already at the point where you need specialised hardware for it to pay for itself at all. 10 years ago, yes, it would've paid for itself, but it would've been a gamble.

Yep, heat is heat. If you manage to swap in your hardware for grandma's electric heater, you have free electricity for whatever you do.

But you need to make sure that the hardware is operated for sufficient time to pay for itself. Without end users harvesting your hw, data.

I think there can be a business to be made here, but it is not trivial at all.

Disclaimer: I consider this a scam

There is a company I saw (and I found it again by googling but I think it's the same) that sells you a heater that pays you some portion of the cryptocurrency it mines:

https://heatbit.com/

I can use the tube amplifier from my grandpa as a heater :-)

It is this brand: https://ms-vint-audio.de/kleinhummel-ks-57-restauration-eine...

I have heated portions of my home with S9s for a while. I know a guy who heats his pool with ASIC miners. It's not hard, but it is more expensive than conventional methods (additional cost not totally offset by proceeds). You should do it if you're interested.

See also https://finance.yahoo.com/news/nyc-bathhouse-mining-bitcoin-...

For electric heating: modern heat pumps have a 1:4 to 1:5 energy input to energy output ratio. They spend energy to move heat. Which also means that they can be used in reverse.

Simple. My servers do not sufficiently heat up the room in winter. An entire data center is one thing, but for regular people, heaters do a better job heating.

Conventional heaters are much more BTUs/watt efficient.

EDIT: By conventional I meant typical/normal, my fault for forgetting that conventional has a specific meaning.

So a heater I have in the house should be a subsidized equipment that does some unknown computation for a third party using electricity provided by me, or what is the idea here? Also, a lot, if not most of the new datacenters utilise the waste heat.

Who's putting up all the $Trillions, to replace large "just a big resistor" electric heaters with fancy new computers?

Where's the market for all that extra computing power? The market for bitcoin is quite limited. And, at scale, the resources poured into manufacturing bitcoin mining rigs are not available to meet other human needs.

For industrial heating applications, where the output temperature of the heater can easily be 500 °C or higher, what sort of computer hardware would work?

>A Bitcoin miner is more expensive to produce and maintain, yes, but over its lifetime shouldn't it pay for itself?

No. They won't pay for themselves at current prices with current difficulty even if you get "free" electricity

And the electricity isn't really free either, a heat pump style heater like a portable AC is about 300% efficient.

They break down too fast being exposed to that much heat so it’s not a good experience

Whatever efficiency you gain in the winter will largely be offset during the Summer.

I think there are a few reasons.

The parts of the country that get cold the most usually don't use electricity as a heating source. Natural gas is a ton cheaper than electric resistive heat. I don't know if a Bitcoin miner will produce heat as efficiently as an electric heater, but even if it does it's still a ton less efficient than natural gas.

If you live in an area that does use electricity for heat, an electric heat pump is going to be around 3x more efficient than electric resistive heat. Instead of creating heat, it's basically transferring heat (from the outside to inside your home). You're never in a situation where "there's no heat outside." It's never zero kelvin. Heat pumps do become less effective as the temperature gets colder, but you can get ones that are still over 2x more efficient even at 0F (-18C).

The part of the country that typically uses electricity for heat is often Maryland and south of that on the East Coast or Washington and Oregon which have temperate winters. Above freezing, a decent heat pump will be around 3x more efficient than electric resistive heating. At 50F (10C), it could be 4x more efficient. Even in a cold city like Boston, the mean daily temperature in December is over 35F. It does dip a bit below freezing for January/February at 29.9F and 31.8F, but at those temperatures a heat pump is likely to be at least 2.5x more efficient if not 3x more efficient. If New England electricity rates weren't so high, it could even be cheaper than natural gas (New England's electric rates are far higher than most of the country at 28.12c per kWh compared to 19.92c for Mid Atlantic, 16.53c for East North Central, 13.29c for West North Central, 15.11 for South Atlantic, 13.5c for East South Central, 14.07 for West South Central, 13.90 for Mountain, and 20.83 for Pacific Contiguous).

Basically, electric resistive heating is incredibly wasteful and using waste heat from computers wouldn't make that an effective heating plan compared to natural gas or heat pumps. Someone else noted that we use 150x more heating energy than computer energy so heat pumps will make a big impact while computer heat won't.

We'd never want to do more computing to harness the heat. We'd want to get that heat from more efficient sources.

> You can use heat pumps for extra gains on either, right?

No. That's not how a heat pump works. A heat pump takes heat from one place and puts it in another place. If the bitcoin miner is inside your home, all of its heat is already inside your home. If the bitcoin miner was outside your home, a heat pump could move that heat inside your home, but you'd be losing some of it along the way. Heat pumps don't multiply heat. They simply move it. If the heat is already inside your place, there's nothing to be moved.

I'd also note that data centers can potentially locate themselves near better sources of power. Some regions have a lot of hydro power which is a cheap and low-carbon way of getting electricity. Plugging in a bitcoin miner in New England where your additional demand will mean burning more natural gas or coal isn't going to be a good way to create heat. You're essentially taking natural gas, turning it into electricity and losing 60% of that heat/energy, transmitting that electricity and losing another 5% of it, and then wanting to turn that electricity back into heat. It'd be better to burn the natural gas in your home and use its heat directly.

So, there's not nearly enough waste heat for it to really move the needle on heating, heat pumps can mean a 50-80% reduction in energy usage rather than a less than 1% savings by re-using the small amount of waste heat, the coldest places typically use more efficient heating sources already, and data centers can locate themselves with good proximity to better/cheaper supplies of power than you typically get in your home.