6 ms·

Didn't watch the video, but a quick point on how the energy efficiency of this works out: Electric heaters are 100% efficient at turning electrical energy into

Didn't watch the video, but a quick point on how the energy efficiency of this works out: Electric heaters are 100% efficient at turning electrical energy into heat. All the energy they take in, that's where it goes. Bitcoin mining (and computers in general) are basically in the same boat. There's some ancillary energy use for blowing air around or shining lights or making sound waves, but for the most part the electricity turns into heat and does some math along the way. Sounds great! Perfectly efficient! But the important caveat is that heat pumps are (effectively) more than 100% efficient. They can take 100 watt of electricity to transfer 300 watts of heat from outside to inside. It's not technically a measure of "efficiency", we call this the "coefficient of performance" instead. Or we call it the "seasonal energy efficiency ratio", which is the same thing except multiplied by some constant factor because somebody wanted a scale that went up to higher numbers. Or for heating, the heating season performance factor, which I forget the specifics of, but is geared toward how well it works pumping heat in from outdoors when your heat source (outdoors) is very cold. In short, it's just as efficient as any other electric heater, but heat pumps are 3-4x better than that.

tlrobinson 9y ago
> But the important caveat is that heat pumps are (effectively) more than 100% efficient. Well, yes, but heat pumps can't mine Bitcoin :)
mrfusion 9y ago
To be fair a heat pump probably wouldn’t work in Siberia with such low temperatures. Most heat pumps are no good below 20f.
- wlesieutre 9y ago
  That's true, I'm speaking more generally about bitcoin mining for heat, but it may make more sense in Siberia if electric heaters are the dominant heating method. There are other reasons electrical heating isn't great, heat pumps aside. An average coal plant (in the US in 2015, I'm using EIA numbers) was about 34% efficient in turning the energy in coal into electricity. Then you lose about 5% of that in transmission, so from the heat released by burning coal you're only getting 32% of that as electricity at your house. Converting 100% of that into heat is pretty unimpressive in the big picture, you'd get 3x more heat by buying some coal and setting it on fire. Obviously you can't do that, but a high efficiency gas-fired furnace will get 90%-98% of the combustion heat into your ducts, with the much smaller remainder going up the chimney. Unless you're on solar power (or some other renewable), burning fossil fuels on-site does better than resistive electric heating. Of course that may also not apply to Siberia. If the ground is frozen all the time it's harder to run gas lines compared to putting in an electric grid. Mostly I'm trying to dissuade anyone in most of the US from stocking up on mining machines thinking it'll be a great heating system.
  - wallace_f 9y ago
    That's pretty reasonable, but let's get really serious--You can be more efficient than that. This winter I may buy a bicycle-electric generator, an inverter, and use it to power my laptop to mine bitcoins. This heating beats a mere 98% gas heater by capturing generated heat most efficiently: Directly inside my body. The remaining kinetic and electric energy heats my house. And since I need to lose weight anyways, the cost of electricity is less than zero. Infinite efficiency! I can't wait to get rich and be warm this winter.
    - ph0rque 9y ago
      How many miles cycled = one bitcoin mined?
      - njarboe 9y ago
        To the moon.
      - wallace_f 9y ago
        I don't know, but according to this reddit post(1), I could hope to earn maybe 1 cent after a year of non-stop cycling. But I would never be cold for a whole year. 1-https://www.reddit.com/r/Bitcoin/comments/6cf1wn/i_mined_bitcoin_for_33_straight_hours_with_my/ https://www.reddit.com/r/Bitcoin/comments/6cf1wn/i_mined_bit...
        Hextinium 9y ago
        If you used Gridcoin then you would be using you computer for something more useful (doing science) and you would get better payout too!
    - jaggederest 9y ago
      Ah, but the total efficiency of getting and consuming calories is quite poor. Unless you eat coal, in which case it's probably other problems that are primary.
    - 9y ago
- exDM69 9y ago
  Heat pumps would still work most of the year, even in Siberia. Different models have different operating ranges. I have 3 heat pumps that are good to -20 Celsius (-4 F), one of them even a bit colder.
- deleted 9y ago
  [deleted]
DINKDINK 9y ago
>heat pumps are (effectively) more than 100% efficient The CoP of a heat pump is greatly dependent on the difference in temperature potential of the source and sink. If it's extremely cold outside, it's very hard to pump heat from colder air into a house. When the temperature potential between the two reservoirs is equal, sure the CoP beats out electric heating but when it's high (When your house is warm and the outside is below freezing) its extremely poor. http://alliedthermaldesigns.com/wp-content/uploads/2012/10/TEC-Perf-COP-27C-12785.jpg http://alliedthermaldesigns.com/wp-content/uploads/2012/10/T...
- wlesieutre 9y ago
  Very true for air source heat pumps. Ground source is still an option for colder areas, but that's a much more involved installation.
- maxerickson 9y ago
  Your link is for Peltier coolers. This government study of an air source heat pump maintained a real world COP of ~3 in Connecticut: https://www.nrel.gov/docs/fy13osti/56393.pdf https://www.nrel.gov/docs/fy13osti/56393.pdf It would be pretty bad to design a heat pump that dropped much below 1, better to just install a big resistive element.
  - DINKDINK 9y ago
    Cool data. Appears the CoP vs outdoor temp plots are on page 14. Since the data doesn't provide temperature delta between the source and sink, you'd need to assume that the pump met the heat delivery requirements.
wallace_f 9y ago
>There's some ancillary energy use for blowing air around or shining lights or making sound waves I believe this isn't really an exception, this energy would also just be converted to heat?
- dest 9y ago
  Agree.
- wlesieutre 9y ago
  At some point, yes, but if the sound is audible outside your house or the light shines out the window then it didn't turn into heat where you wanted it to. So not 100% of that sound or light will be an exception, but some of it might.
deleted 9y ago
[deleted]
vlunkr 9y ago
Pretty clever, I've never thought about it like that. Basically they turned a computer into a heater that pays for itself plus some. Makes you think we should be building datacenters where the heat could be used, rather than just pumping it out.
- rzzzt 9y ago
  There was an attempt to host servers in a similar setup in regular houses, not sure what happened to it (the article link doesn't seem to work, either): https://news.ycombinator.com/item?id=9334792 https://news.ycombinator.com/item?id=9334792
- blacksmith_tb 9y ago
  That was the premise behind this machine[1] (love the unintentionally humorous product rendering) but for some reason I haven't seen them popping up everywhere. 1: https://bitcoinnewsmagazine.com/bitmain-antminer-r4-home-bitcoin-miner/ https://bitcoinnewsmagazine.com/bitmain-antminer-r4-home-bit...
- aoner 9y ago
  Check out https://www.nerdalize.com https://www.nerdalize.com
SilasX 9y ago
>It's not technically a measure of "efficiency", we call this the "coefficient of performance" instead. I have to disagree. At its most general, the concept of efficiency means "desired output achieved per unit of scarce good expended" and can be applied in a variety of contexts: new users per dollar spent on marketing is a measure of your marketing efficiency, treasure value found per hour spent searching is a measure of your treasure-finding efficiency, etc. Heat pumps are just a case where a) we use the same units for output and input even though they're different things, and b) in that unit system, the value for the output can be greater than the input. Since people can be unnecessarily suspicious of >100% efficiency, they use different terms for it. If you expressed the efficiency as "2 joules of heat moved per joule of mains electricity consumed" you eliminate the canceling that would let you phrase the ratio as 200%.
- darkmighty 9y ago
  > If you expressed the efficiency as "2 joules of heat moved per joule of mains electricity consumed" you eliminate the canceling that would let you phrase the ratio as 200%. But that's the performance. Efficiency is usually a measure of how good the performance is. In this case there's a practical reason not to call it efficiency, because there is a well understood maximum performance which is the Carnot limit, so for practical purposes (to avoid confusion) PumpedHeat/Power is called "coefficient of performance"and CarnotLimit/PumpedHeat is called "efficiency", and it has the usual properties that it cannot exceed 100% and it measures how well your system works in a more or less absolute sense.
  - jaakl 9y ago
    Heat pump takes energy from two sources, power grid and outside environment: air, landmass or water (there are even air+land models etc). Their energy output is always less than sum of sources, so their efficency is never over 100%. But as the ambient land/air/water heat is generally ”free” then we seem to get 3-500% economy. I have never even seen the technical/physical efficiency numbers for heat pumps as consumers do not care about this.
exDM69 9y ago
A coworker of mine mines ETH to heat his house and I am considering that too. I am not sure how much you can save money compared to electric heating when you account for the cost of GPUs, though. Heat pumps have better energy efficiency than electric heaters but whether that translates to cheaper costs is another thing. Heat pumps are expensive (about $3000 per pump) and they require regular maintenance (a few hundred bucks per pump every few years). They're also big, bulky and noisy and installation requires poking holes in exterior walls. I have 3 heat pumps and 2 fire places in my house but I still do need a bunch of electric heaters when it gets properly cold. The weather around here is right about freezing this time of year and so far no electric heaters are needed. But soon it's time to turn on the heat and it's a consideration of money, not energy efficiency.
- guy_c 9y ago
  Just some rough numbers for you: A GTX1060 6GB can mine ETH at around 80 watts. And currently, earn you $25/month of ETH with electricity costing $10/month. Cost of card is $260. https://www.cryptocompare.com/mining/calculator/eth?HashingPower=18&HashingUnit=MH%2Fs&PowerConsumption=80&CostPerkWh=0.18 https://www.cryptocompare.com/mining/calculator/eth?HashingP...
andbberger 9y ago
This is silly, CPUs are 100% efficient at converting electrical energy into heat. Where do you think that 'ancillary energy' is going? Obviously heat pumps are more efficient - that's kinda beside the point though. The main point here is you can take anywhere you had a resistive heating element and replace it with a mining chip, and you're now doing something useful with that energy you were turning into heat anyway. Yes heat pumps are more efficient but there are plenty of places in your house you have plain old heat elements that aren't going away (water heater).
- Retric 9y ago
  CPU's can't tolerate high temperatures so it only works for a small subset of things you need a heating element for. Aka, you can uses them to cook with. Also, while you can use electricity to heat water it's vastly more efficient to burn natural gas to make heat than burn natural gas to make electricity to make it, ditto solar power etc.
- adrianmonk 9y ago
  Actually, heat pump water heaters are a thing. They are also called "hybrid" water heaters. They cost more money, but Consumer Reports says "payback time is short" (see https://www.consumerreports.org/cro/water-heaters/buying-guide https://www.consumerreports.org/cro/water-heaters/buying-gui... ). They probably don't make as much sense in cold climates, but where I live, air conditioning in the summer (and spring and fall) dwarfs the energy usage from heating in the winter. So a device that makes it colder on average indoors would be a net win even if it didn't have the function of heating your water.
  - yourapostasy 9y ago
    When I looked into these units, the potential repair costs over time led me to choose a highly insulated electric (Rheem Marathon series). The major parts like the compressor were not available through Grainger or even an HVAC supply store, nor could I get my hands on a retail parts price list. So I had concerns over vendor lock-in, and the initial capital premium would get vastly inflated in opex costs over time. Has anyone had 7+ years experience with these, and if so, can you please share your ownership experience and the model & brand you used?
wrcwill 9y ago
Right, heat pumps cost 4x less, but a miner is returning profit. The only argument to be had is an ecological one. Mining is cheaper than a heat pump, gas, etc..
TedLePoireau 9y ago
This is what we are doing at Qarnot Computing for 5years. We created a heater using CPU as a heat source. People send a docker image (3d rendering, financial analysis...) and we run it on heaters deployed in buildings in Paris where people are heated for free (we refund the electricity cost) https://computing.qarnot.com https://computing.qarnot.com https://www.qarnot.com/faq/ https://www.qarnot.com/faq/ Disclosure: I work there :)
- Faaak 9y ago
  Love the idea ! I would love to work with you if I didn't have a nice project in the same time. Small error in the FAQ though: "kW/h" ;-)
  - TedLePoireau 9y ago
    I'll make sure this is fixed on Monday ! Thank you :)
    - brieyr 9y ago
      If you are referring to the unit of energy it should be kWh as in (Energy / Time) * Time rather than unit power per unit time. https://en.wikipedia.org/wiki/Kilowatt_hour https://en.wikipedia.org/wiki/Kilowatt_hour
- aoner 9y ago
  Why don't you use boilers? That way you can use the heating year round.
abysmalfitzg 9y ago
Is this the "famous" "siberian coefficient"? https://books.google.com/books?id=A4DGiaOn3BwC&pg=PA167&dq=%22northern+coefficient%22+%22mines%22&hl=en&sa=X&ved=0ahUKEwj09Yj24KPXAhVHfiYKHYrqAdIQ6AEIJjAA#v=onepage&q=%22northern%20coefficient%22%20%22mines%22&f=false https://books.google.com/books?id=A4DGiaOn3BwC&pg=PA167&dq=%...

tlrobinson 9y ago

> But the important caveat is that heat pumps are (effectively) more than 100% efficient. Well, yes, but heat pumps can't mine Bitcoin :)

mrfusion 9y ago

To be fair a heat pump probably wouldn’t work in Siberia with such low temperatures. Most heat pumps are no good below 20f.

wlesieutre 9y ago
That's true, I'm speaking more generally about bitcoin mining for heat, but it may make more sense in Siberia if electric heaters are the dominant heating method. There are other reasons electrical heating isn't great, heat pumps aside. An average coal plant (in the US in 2015, I'm using EIA numbers) was about 34% efficient in turning the energy in coal into electricity. Then you lose about 5% of that in transmission, so from the heat released by burning coal you're only getting 32% of that as electricity at your house. Converting 100% of that into heat is pretty unimpressive in the big picture, you'd get 3x more heat by buying some coal and setting it on fire. Obviously you can't do that, but a high efficiency gas-fired furnace will get 90%-98% of the combustion heat into your ducts, with the much smaller remainder going up the chimney. Unless you're on solar power (or some other renewable), burning fossil fuels on-site does better than resistive electric heating. Of course that may also not apply to Siberia. If the ground is frozen all the time it's harder to run gas lines compared to putting in an electric grid. Mostly I'm trying to dissuade anyone in most of the US from stocking up on mining machines thinking it'll be a great heating system.
- wallace_f 9y ago
  That's pretty reasonable, but let's get really serious--You can be more efficient than that. This winter I may buy a bicycle-electric generator, an inverter, and use it to power my laptop to mine bitcoins. This heating beats a mere 98% gas heater by capturing generated heat most efficiently: Directly inside my body. The remaining kinetic and electric energy heats my house. And since I need to lose weight anyways, the cost of electricity is less than zero. Infinite efficiency! I can't wait to get rich and be warm this winter.
  - ph0rque 9y ago
    How many miles cycled = one bitcoin mined?
    - njarboe 9y ago
      To the moon.
    - wallace_f 9y ago
      I don't know, but according to this reddit post(1), I could hope to earn maybe 1 cent after a year of non-stop cycling. But I would never be cold for a whole year. 1-https://www.reddit.com/r/Bitcoin/comments/6cf1wn/i_mined_bitcoin_for_33_straight_hours_with_my/ https://www.reddit.com/r/Bitcoin/comments/6cf1wn/i_mined_bit...
      - Hextinium 9y ago
        If you used Gridcoin then you would be using you computer for something more useful (doing science) and you would get better payout too!
  - jaggederest 9y ago
    Ah, but the total efficiency of getting and consuming calories is quite poor. Unless you eat coal, in which case it's probably other problems that are primary.
  - 9y ago
exDM69 9y ago
Heat pumps would still work most of the year, even in Siberia. Different models have different operating ranges. I have 3 heat pumps that are good to -20 Celsius (-4 F), one of them even a bit colder.
deleted 9y ago
[deleted]

DINKDINK 9y ago

>heat pumps are (effectively) more than 100% efficient The CoP of a heat pump is greatly dependent on the difference in temperature potential of the source and sink. If it's extremely cold outside, it's very hard to pump heat from colder air into a house. When the temperature potential between the two reservoirs is equal, sure the CoP beats out electric heating but when it's high (When your house is warm and the outside is below freezing) its extremely poor. http://alliedthermaldesigns.com/wp-content/uploads/2012/10/TEC-Perf-COP-27C-12785.jpg http://alliedthermaldesigns.com/wp-content/uploads/2012/10/T...

wlesieutre 9y ago
Very true for air source heat pumps. Ground source is still an option for colder areas, but that's a much more involved installation.
maxerickson 9y ago
Your link is for Peltier coolers. This government study of an air source heat pump maintained a real world COP of ~3 in Connecticut: https://www.nrel.gov/docs/fy13osti/56393.pdf https://www.nrel.gov/docs/fy13osti/56393.pdf It would be pretty bad to design a heat pump that dropped much below 1, better to just install a big resistive element.
- DINKDINK 9y ago
  Cool data. Appears the CoP vs outdoor temp plots are on page 14. Since the data doesn't provide temperature delta between the source and sink, you'd need to assume that the pump met the heat delivery requirements.

wallace_f 9y ago

>There's some ancillary energy use for blowing air around or shining lights or making sound waves I believe this isn't really an exception, this energy would also just be converted to heat?

dest 9y ago
Agree.
wlesieutre 9y ago
At some point, yes, but if the sound is audible outside your house or the light shines out the window then it didn't turn into heat where you wanted it to. So not 100% of that sound or light will be an exception, but some of it might.

deleted 9y ago

[deleted]

vlunkr 9y ago

Pretty clever, I've never thought about it like that. Basically they turned a computer into a heater that pays for itself plus some. Makes you think we should be building datacenters where the heat could be used, rather than just pumping it out.

rzzzt 9y ago
There was an attempt to host servers in a similar setup in regular houses, not sure what happened to it (the article link doesn't seem to work, either): https://news.ycombinator.com/item?id=9334792 https://news.ycombinator.com/item?id=9334792
blacksmith_tb 9y ago
That was the premise behind this machine[1] (love the unintentionally humorous product rendering) but for some reason I haven't seen them popping up everywhere. 1: https://bitcoinnewsmagazine.com/bitmain-antminer-r4-home-bitcoin-miner/ https://bitcoinnewsmagazine.com/bitmain-antminer-r4-home-bit...
aoner 9y ago
Check out https://www.nerdalize.com https://www.nerdalize.com

SilasX 9y ago

>It's not technically a measure of "efficiency", we call this the "coefficient of performance" instead. I have to disagree. At its most general, the concept of efficiency means "desired output achieved per unit of scarce good expended" and can be applied in a variety of contexts: new users per dollar spent on marketing is a measure of your marketing efficiency, treasure value found per hour spent searching is a measure of your treasure-finding efficiency, etc. Heat pumps are just a case where a) we use the same units for output and input even though they're different things, and b) in that unit system, the value for the output can be greater than the input. Since people can be unnecessarily suspicious of >100% efficiency, they use different terms for it. If you expressed the efficiency as "2 joules of heat moved per joule of mains electricity consumed" you eliminate the canceling that would let you phrase the ratio as 200%.

darkmighty 9y ago
> If you expressed the efficiency as "2 joules of heat moved per joule of mains electricity consumed" you eliminate the canceling that would let you phrase the ratio as 200%. But that's the performance. Efficiency is usually a measure of how good the performance is. In this case there's a practical reason not to call it efficiency, because there is a well understood maximum performance which is the Carnot limit, so for practical purposes (to avoid confusion) PumpedHeat/Power is called "coefficient of performance"and CarnotLimit/PumpedHeat is called "efficiency", and it has the usual properties that it cannot exceed 100% and it measures how well your system works in a more or less absolute sense.
- jaakl 9y ago
  Heat pump takes energy from two sources, power grid and outside environment: air, landmass or water (there are even air+land models etc). Their energy output is always less than sum of sources, so their efficency is never over 100%. But as the ambient land/air/water heat is generally ”free” then we seem to get 3-500% economy. I have never even seen the technical/physical efficiency numbers for heat pumps as consumers do not care about this.

exDM69 9y ago

A coworker of mine mines ETH to heat his house and I am considering that too. I am not sure how much you can save money compared to electric heating when you account for the cost of GPUs, though. Heat pumps have better energy efficiency than electric heaters but whether that translates to cheaper costs is another thing. Heat pumps are expensive (about $3000 per pump) and they require regular maintenance (a few hundred bucks per pump every few years). They're also big, bulky and noisy and installation requires poking holes in exterior walls. I have 3 heat pumps and 2 fire places in my house but I still do need a bunch of electric heaters when it gets properly cold. The weather around here is right about freezing this time of year and so far no electric heaters are needed. But soon it's time to turn on the heat and it's a consideration of money, not energy efficiency.

guy_c 9y ago
Just some rough numbers for you: A GTX1060 6GB can mine ETH at around 80 watts. And currently, earn you $25/month of ETH with electricity costing $10/month. Cost of card is $260. https://www.cryptocompare.com/mining/calculator/eth?HashingPower=18&HashingUnit=MH%2Fs&PowerConsumption=80&CostPerkWh=0.18 https://www.cryptocompare.com/mining/calculator/eth?HashingP...

andbberger 9y ago

This is silly, CPUs are 100% efficient at converting electrical energy into heat. Where do you think that 'ancillary energy' is going? Obviously heat pumps are more efficient - that's kinda beside the point though. The main point here is you can take anywhere you had a resistive heating element and replace it with a mining chip, and you're now doing something useful with that energy you were turning into heat anyway. Yes heat pumps are more efficient but there are plenty of places in your house you have plain old heat elements that aren't going away (water heater).

Retric 9y ago
CPU's can't tolerate high temperatures so it only works for a small subset of things you need a heating element for. Aka, you can uses them to cook with. Also, while you can use electricity to heat water it's vastly more efficient to burn natural gas to make heat than burn natural gas to make electricity to make it, ditto solar power etc.
adrianmonk 9y ago
Actually, heat pump water heaters are a thing. They are also called "hybrid" water heaters. They cost more money, but Consumer Reports says "payback time is short" (see https://www.consumerreports.org/cro/water-heaters/buying-guide https://www.consumerreports.org/cro/water-heaters/buying-gui... ). They probably don't make as much sense in cold climates, but where I live, air conditioning in the summer (and spring and fall) dwarfs the energy usage from heating in the winter. So a device that makes it colder on average indoors would be a net win even if it didn't have the function of heating your water.
- yourapostasy 9y ago
  When I looked into these units, the potential repair costs over time led me to choose a highly insulated electric (Rheem Marathon series). The major parts like the compressor were not available through Grainger or even an HVAC supply store, nor could I get my hands on a retail parts price list. So I had concerns over vendor lock-in, and the initial capital premium would get vastly inflated in opex costs over time. Has anyone had 7+ years experience with these, and if so, can you please share your ownership experience and the model & brand you used?

wrcwill 9y ago

Right, heat pumps cost 4x less, but a miner is returning profit. The only argument to be had is an ecological one. Mining is cheaper than a heat pump, gas, etc..

TedLePoireau 9y ago

This is what we are doing at Qarnot Computing for 5years. We created a heater using CPU as a heat source. People send a docker image (3d rendering, financial analysis...) and we run it on heaters deployed in buildings in Paris where people are heated for free (we refund the electricity cost) https://computing.qarnot.com https://computing.qarnot.com https://www.qarnot.com/faq/ https://www.qarnot.com/faq/ Disclosure: I work there :)

Faaak 9y ago
Love the idea ! I would love to work with you if I didn't have a nice project in the same time. Small error in the FAQ though: "kW/h" ;-)
- TedLePoireau 9y ago
  I'll make sure this is fixed on Monday ! Thank you :)
  - brieyr 9y ago
    If you are referring to the unit of energy it should be kWh as in (Energy / Time) * Time rather than unit power per unit time. https://en.wikipedia.org/wiki/Kilowatt_hour https://en.wikipedia.org/wiki/Kilowatt_hour
aoner 9y ago
Why don't you use boilers? That way you can use the heating year round.

abysmalfitzg 9y ago

Is this the "famous" "siberian coefficient"? https://books.google.com/books?id=A4DGiaOn3BwC&pg=PA167&dq=%22northern+coefficient%22+%22mines%22&hl=en&sa=X&ved=0ahUKEwj09Yj24KPXAhVHfiYKHYrqAdIQ6AEIJjAA#v=onepage&q=%22northern%20coefficient%22%20%22mines%22&f=false https://books.google.com/books?id=A4DGiaOn3BwC&pg=PA167&dq=%...