Bitcoin Forum

Possible uses for heat generated by btc mining....Someone on the forums said they heat their house with their mining rig. What else could be done with the heat? What are people already using it for?

Some ideas I was thinking about....

Hot water heater for a house or hotel
Instant Hot Water for faucets
Steam Generators
Sauna
Hot Tub
Cooking food

Anything else that might be kinda crazy?

A few threads that I remember:

Bathroom floor heating: https://bitcointalk.org/index.php?topic=3707.msg53879#msg53879
"Dehydrated strawberries": https://bitcointalk.org/index.php?topic=52331.msg624415#msg624415
Uses of waste mining heat: https://bitcointalk.org/index.php?topic=52340.0;all
Harrassing wasted heat? Post your pics and ideas!: https://bitcointalk.org/index.php?topic=155841.0;all

The BFL Jalapeno was supposed to be a coffee warmer.  They even sent me a coffee cup.  But the top of the thing is the coolest part of it.  It's not a very well designed coffee warmer.

The main problem is that the usable heat coming off the miners is low grade by the nature of silicon.  You can't run 120-200C temperatures and expect anything to either run or last long.

So you're stuck with "warm but not hot" temperatures, which are mostly useful for heating.  That's about all you can expect from it.

Further, you typically would want the miners running constantly, so you need something that can sink a steady source of lowgrade heat.  Room heating or water preheating are the obvious solutions.

The most economical is probably a preheater for the hot water heater, but you'd have to go through a good bit of hot water to make it worth it.

I have a hybrid domestic hot water heater. it uses a heat pump to remove heat from the air and put it into the tank for our use.

similar to this one:
http://www.geappliances.com/heat-pump-hot-water-heater/

and my miners are in the basement...

Why go crazy? It's starting to get cold, here. Just need a fan or two, and the heat's no longer wasted. Poof. ~100% efficiency.

Dyson spheres?
Considering that Nuclear power plants are nothing but really complicated water heaters, scaling up mining rigs to planetary levels might be cool. Also redundancy is neat.
http://3.bp.blogspot.com/-Um2mjwKOMl4/T2jm4FFQHbI/AAAAAAAADSo/F-RIiC4Wsu4/s320/fractal_dyson_sphere_by_eburacum45-d2yum16.jpeg

Why its not possible to use the energy inside a 50°C flux of water to finally move a turbine (150°C)?
Isn't there any way to do it?
Its just a curiosity I had for a long time, non bitcoin related.

Short answer: The laws of thermodynamics prohibit it.

Your maximum efficiency of a heat engine is determined by the absolute temperatures of the hot side and cold side.

For the output of a miner, the hot side is barely warmer than the cold side.  The theoretical power output is present but tiny.

It is not that you CAN'T it is that it won't be very efficient.  Remember there is no such thing as free electricity even if you have a free/waste heat source; there is always a capital cost and all equipment has a finite lifespan.  So if your $10,000 turbine produces so little electricity over its economical lifespan that it has an average cost of $1.00 per kWh it doesn't really make sense.   The hotter the input and the colder the output the more efficient the energy conversion is (thermal energy to electrical energy).


The waste heat from miners is simply too "cool" to be useful for power generation.   It can be useful for heat (either heating the air in a house, or heating water) but even then you have some material costs and you likely need to "water cool" your rigs.  Trying to capture waste heat from the air is an excercise in futility.

On edit: Bitweasel beat me.

The heat can be useful, looking forward to it now that I'm moving into a house with single glazing and £26/month fixed electric bill.

I have a unit with dual watercoold VGAs that sits under my desk.  The heat it gives off through the top vented radiator is nice when its cold out.  When its hot, I just keep a small fan under there.

I actually dry my laundry in a rack in the mining room.  Although some may say that might not be such a good idea with all the moisture in the room but it's not like I'm adding a whole lot of humidity either.

I think you could use it as a heat cource for a super efficient stirling engine which you could then attach to an electric generator.

Physics still wins.  The problem is that the hot side to cold side difference isn't that high, so you can't extract much energy from it...

+1

my mother was worried about a pair of socks not drying in time and she joked that i should wash it then after squeezing out as much water as possible, hang it at the exhaust of my avalon batch 1 ;D

I dunno, my Avalon gets pretty warm. And there are stirling engines that can run just from the heat of your hand.

I didn't say you couldn't extract any energy.

I said you couldn't extract much. Go load up one of those sterling engines that runs on a low heat delta and calculate how much usable energy you get.

Tried using it to boil an egg but after 2 hour it is half boiled :)

I live in the Great North Woods and there is a frost nearly every morning now.  It's heating my house as I write this.

I should factor that in, wood and oil heat cost money.

I remember seeing some post state that you can use heat to covert it back to energy. Just that the technology is not mature enough and won't ROI. Maybe in the future we can.

second law of thermodynamics my friend i believe is what you will be trumped by here every time.  And the loss of energy through inefficiencies and just changing energy states.

I'm heating my house right now. last night it was -1c and I had to turn on my AC!

I put my miners' heat to good use:

Toast:
https://i.imgur.com/ZmM9gbA.jpg?1

Frying cats and eggs:
https://i.imgur.com/h0WRZ7F.jpg?1

https://bitcointalk.org/index.php?topic=301764 (https://bitcointalk.org/index.php?topic=301764)

Lolz, I am so ganna try this. Putting my bread in-between 2 GPU.

It's very low grade heat. Room heating is about all it is good for.

Well, my GPU can hit 80-90c depending on my overclock and setting. If I have like 7 and I can find a way to direct my heat. It would be lots of heat..

That's still very low grade heat compared to an ambient room temperature of 20C!

90C (very hot for a GPU) is 363K.
20C (room temperature) is 293K.

The maximum theoretical efficiency for this is 1 - (293/363) = 19.2%

So, at BEST, you can get 200W per 1000W.  Realistically, you'll be lucky to get half of that, for a rather major cost.

It'd be really cool to implement a wintertime driveway/road heater powered by waste heat.

Something like,
1. Run a bunch of pipes under the surface of a blacktop or gravel (probably easier) driveway or road
2. Circulate coolant through the pipes and through radiators (with fans) placed in the indoor mining room(s)
3. Coolant would be cooled outside under the road surface, transferring heat to melt snow/ice
4. Coolant would be heated in radiators in the mining rooms, drawing heat from the air and cooling the mining room.
- Optionally install temperature probes on the radiator inlets and outlets and automatically shut the system off if the amount of heat transferred out of the room drops below a certain threshold. (i.e., when it's too warm outside)
- Optionally put water blocks on mining processors and use heat exchangers to more efficiently transfer heat into the driveway coolant loop

Wouldn't be practical for everyone, but most people here in the Northeast US (and everywhere else it snows) hate shoveling snow off their driveway.  The constant heat produced by mining could always keep the driveway warm enough such that snow melts upon contact and never has a chance to accumulate. 

Although my plan this winter is to simply move some mining equipment out of the basement and into my apartment where I can enjoy the free heat. :)

Best use I found was

tropical fish tank or reptile vivarium

free heat for pets you would otherwise have to waste electricity on to keep warm.

Heating house in winter is not a bad idea, but you will turn off the miners in summer ? Because in summer it cost a lot of electricity to just cool your miners.

What do you mean? I tried warming my tea and it works :P

That's a use for low grade heat. Not extracting energy with a heat engine.

The heat would be perfect for anaerobic digestion to produce natural gas for cooking/heating .

A usb gets to about 70 degrees centigrade .
I have 11 in a 20 litre bucket of oil ,average temperature 30 degrees .I can add more usb's to get the temperature to the optimum body temperature of 37oC.

Throw poo, wee ,and waste food matter,peeling and such in a 1000 litre container with the drum of oil sealed inside  ,after 3 weeks I have all the free gas I could need for a family of 5,just keep adding crap and mining coins = win .

I personally have produced gas and it felt really good to see a blue flame come out of shite .
I used an immersion heater to experiment but that was before asic heaters were invented lol

Best I can think of is use it as a warmer. Maybe toast a bread but would take hours