9 ms·

Install a server in your house, get free hot water!

74 points by btdmaster 4y ago

freeqaz 4y ago
I wonder if you could do this yourself with a heat exchange (like from McMaster-Carr). I've read before that if you run the loops "backwards", such that the two loops of the heat exchanger are flowing in opposite directions, that you can increase the rate of heat transfer by maximizing the difference in temperature. Has anybody done this before?
- oakwhiz 4y ago
  That's the normal way to do it and it's part of the reason why many devices label the supply and return fittings.
- smileysteve 4y ago
  If i were running a mining rig, that's how i would do it.
- cypherpunks01 4y ago
  This is called a counter-flow heat exchanger or countercurrent exchange, it's very commonly used in industrial applications, for both gas or fluid flow. This setup is very efficient at heat transfer, and can counter-intuitively produce a higher output temperature than the counterflow's input temperature. https://en.wikipedia.org/wiki/Countercurrent_exchange https://en.wikipedia.org/wiki/Countercurrent_exchange
whalesalad 4y ago
very clever but I wonder what kind of workloads are being run on these remote/edge compute nodes. there isn't any homogeneity in the network - everyone is going to be on a different kind of network with a huge variations in bandwidth and latency. can't find any specs on what kind of compute power each physical installation would provide
- colobas 4y ago
  These guys [1] used to be called Nerdalize and iirc their first iteration looked a lot like this. I think they have since moved to a model of a few select locations where nodes are closer to each other. [1] - https://www.leaf.cloud https://www.leaf.cloud EDIT: fixed link
- smileysteve 4y ago
  Most simply it could be used for crypto mining (except the utility would have to upgrade the hardware very often)
  - imhoguy 4y ago
    The compute rig would need to be the size of the water tank to make the business even. Maintenance cost would be much higher too. Better to keep all compute in house sized DC units and just sell hot water to neighbors.
- bob1029 4y ago
  Some workloads I can think of beyond crypto cases: Distributed compilation of large code bases, offline rendering, baking lighting for AAA, media transcoding. Basically, anything batch-style that doesn't demand reliable latency and can tolerate some amount of failure in the cluster.
sammoe13 4y ago
Doing some back of the napkin math, their contractual minimum of 2.5 kWh a day into your water heater works out to 75 kWh a month. This [1] site claims the average two person home uses 195 kWh a month, so it potentially could be a decent offset. I do wonder whether this quoted 2.5 kWh is energy coming off the server into your heater, or if it's measured somewhere else. Energy loss from thermal transfer would make a huge difference in measured input into your heating system. [1] https://www.keysenergy.com/typical-electric-usage-of-various-appliances/ https://www.keysenergy.com/typical-electric-usage-of-various...
- post_break 4y ago
  Where are they getting 195 kWh a month? That's crazy low. Even when I don't need to run the AC or heat I'm in the 800's.
  - sammoe13 4y ago
    Sorry, I should have made it clear that I was referring only to an average two-person home's energy use for creating hot water monthly.
Alupis 4y ago
I'm highly skeptical this thing can provide enough heat energy to warm an entire water tank and keep it warm for the sporadic on-demand loads a hot water tank typically endures. Will it take 3 days to warm back up after a moderately long hot shower while simultaneously running the dishwasher? I'm further skeptical at the claim of a dedicated fiber line being installed just for this server (having been on the receiving side of fiber install quotes with 5-6 digits) - and even more skeptical at the claim of using 4G/5G connections for servers. I'll believe it when I see it... but it reads like it was written by someone that really doesn't have a grasp of what we're dealing with here.
- smileysteve 4y ago
  You may want to re-read; this isn't disabling the current water heater, it is modifying it to be less insulated, and placing a compute unit there. [It will maintain an immersion heater] Re: fiber, Natural gas lines often already have a fiber line for monitoring (some US utils were the first to the fiber market because of this)
  - Alupis 4y ago
    The cost of routing a fiber line is extraordinary. Even if one existed nearby, it would not be usable because it's owned by the utility not this private server company. Regarding keeping the existing heating element - seems necessary because this server water heater isn't going to heat much of anything. To flip it on it's head - this is free cooling capacity for a for-profit server company that will do little-to-zero for the home owner and risks damaging their expensive water heater for some hand-wavy promised savings of $200 a year... not really selling me.
    - smileysteve 4y ago
      Which is more difficult, routing a fiber line or a natural gas line?
      - deleted 4y ago
        [deleted]
smileysteve 4y ago
Natural Gas companies near me began offering fiber services before Google Fiber did; because they had the infrastructure to monitor the lines and distribution nodes; Given that fiber setup, the gas company has a low latency network.
smileysteve 4y ago
This along with the increase in heat pumps, really makes me question air source heat pumps not directly hybridizing with water heaters (new water heaters have heat pumps that will cool your utility closet). But using house heat pumps to cool air / heat water in the summer could at least decrease energy use during the day; and then in the winter, the water (as a heat source) can help assist older heat pumps in pumping heat from the cold (though modern heat pumps solve this problem)
blamazon 4y ago
This could be flipped - I.e. using a Japanese domestic fuel cell[1] one could install a hot water heater in the home, and get 'free' electricity to run a server, that could possibly do something productive to offset the associated capital and operational expenditures. [1] https://www.j-lpgas.gr.jp/en/appliances/ https://www.j-lpgas.gr.jp/en/appliances/ (Interesting aside: some people in Japan combine these with a solar/battery array to achieve robust all-season off grid self sufficiency, without combustion, which I think is quite neat!)
- blacksmith_tb 4y ago
  True, though it'd be using propane / LP gas, where the server-cooled-by-heating-your-water could potentially be powered by electricity from solar or wind...
  - deleted 4y ago
    [deleted]
Havoc 4y ago
Quite surprised that they’re running that off 4G I’ve found tech driven heating to work quite well though. For small apartments you really don’t need all that much output if it’s 24/7
- mike-cardwell 4y ago
  They're not running it off 4G. Click through to the trial and read the FAQ. It's using your home broadband connection.
  - Havoc 4y ago
    So the article is wrong? > the answer is no, as we are told the server uses its own connection which will either be its own dedicated fiber line or a 4G/5G connection.
    - mike-cardwell 4y ago
      Yes
mabbo 4y ago
Worth remembering that you don't need the server to completely heat the water to shower temperature. You can get it part way there, and then it will take less heat to get the water heater the rest of the way. I could imagine a future where every house has something like this partially heating their water and air before the real heating system is applied.
- thatwasunusual 4y ago
  > I could imagine a future where every house has something like this partially heating their water and air before the real heating system is applied. This is really important. Where I live - Oslo, Norway - we have a sun thermal collector-thingy[0] on the roof which _aids_ in heating up other stuff. Surely, it needs to be a fire nearby to heat the water enough to have a comfortable shower, but we save approx. $20K yearly[1] on energy costs with this solution. [0] https://en.wikipedia.org/wiki/Solar_thermal_collector https://en.wikipedia.org/wiki/Solar_thermal_collector [1] I live in a housing association with 60 other families in the same building, so needless to say the savings would be a lot less if I lived on my own in one house. :)
- imhoguy 4y ago
  This is why placing server pretty much anywhere in the well insulated house during cold months contributes to overall heat sum. The only problem is in hot months where that extra heat needs to be removed from the living space. Some inner house heat pump solution could collect that air heat and concentrate it in the water tank.
  - mabbo 4y ago
    Isn't that what this product is doing though?
out-of-ideas 4y ago
title might as well say: get a job, get dollar bills for free!
tonymet 4y ago
in eastern europe they pump hot water directly to homes . it’s waste water from nearby power stations . you could do the same from the data center to homes
- Symbiote 4y ago
  Facebook does exactly that in Odense, Denmark. https://sustainability.fb.com/wp-content/uploads/2020/12/FB_Denmark-Data-Center-to-Warm-Local-Community.pdf https://sustainability.fb.com/wp-content/uploads/2020/12/FB_...
- william_T 4y ago
  most datacenter's will recycle their water. Heat it up, send it somewhere else to cool down, send it back to heat up. Specific datacenters were called out on here last week for dumping heat waste water. The efficiency of moving hot water over long distances doesnt make much sense
  - tonymet 4y ago
    my point is that it's commonly used e.g. in Finland & Russia, so someone has figured out how to get hot water from outside the city into the city and heat homes.
tombert 4y ago
Somewhat tangential, but in my first NYC apartment, our radiator was absolutely terrible, and did a miserable job getting the living room to an even remotely livable temperature. My solution? Two giant rack mount servers, running Foldign@Home at full capacity. Way I figured is that it's still 100% efficient at generating heat, but I might as well help drug research in the process.
- imhoguy 4y ago
  Just curious, how have you handled the noise?
  - mhb 4y ago
    And the electric bill.
  - tombert 4y ago
    We don’t live there anymore, so we don’t, but we honestly just put up with it. I don’t have any pointers on that fact. To the child comment; I’ve told this story in the past but the tldr of it was that I was (unknowingly) not paying for the electricity in my apartment due to a broken meter. I didn’t break it, and I didn’t know it was broken; I just thought power was really cheap in NYC.
- compsciphd 4y ago
  that's the opposite problem that most people (from my experience) have in NYC. Apartments get too much heat (i.e. landlords can get seriously fined if they dont keep the building at a proper temp, so its just easier and safer for them to give too much heat). Also, many radiators in old buildings aren't really adjustable anymore (and hence you get all the heat). so its common for people in NYC to keep their windows open in the middle of winter to try to balance out the temperature.
  - ljnelson 4y ago
    Interestingly, this is often by design: https://www.npr.org/2020/12/10/945136599/how-spanish-flu-pandemic-changed-home-heat-radiators#:~:text=CHANG%3A%20This%20design%20philosophy%20took,from%20coal%20to%20other%20fuels https://www.npr.org/2020/12/10/945136599/how-spanish-flu-pan....
tobyhinloopen 4y ago
I wonder if I can use my water cooled PC to heat water for the shower
amelius 4y ago
What if you go on a trip and don't use hot water for a couple of days?
- mike-cardwell 4y ago
  From the FAQ on the trial page, it seems like it will simply not run if there is nowhere to dump the excess heat: How much of my hot water will it deliver? A useful base load. If the heata unit ran all day it would deliver about 4.8kWh of hot water which is about the amount of hot water an average household uses. In practice the utilisation level will be lower and sometimes the water will be at temperature so the heata unit won't be able to run. We think it could deliver up to 80% of an average household's hot water, with good compute utilisation. This trial will help us learn more about how this will work in practice and enable us to give you a useful amount of free hot water at the same time.
nfcampos 4y ago
So what do people do with these things in summer? Won’t it then heat up their house excessively
- mike-cardwell 4y ago
  Open a window?
- indigomm 4y ago
  It heats the water tank, just as people heat their water tanks now in the summer. No difference really, except some of that energy is free to the homeowner.
LargoLasskhyfv 4y ago
Prior art: https://qarnot.com/en https://qarnot.com/en https://www.leaf.cloud/ https://www.leaf.cloud/ https://www.cloudandheat.com/ https://www.cloudandheat.com/ I wonder how that worked out, given the development of energy prices...
hommelix 4y ago
In Germany the startup that became Cloud&Heat Technologies started with the idea to sell a heating system for home powered by some computers. It seems that they have pivoted to sell 19" rack with water cooling that can be connected to a building heating system, more for companies than individual household. https://www.cloudandheat.com/ https://www.cloudandheat.com/ Here is an article from 2020 in German presenting the computer rack as a heating system. http://www.energiesparhaushalt.de/1/intelligent-heizen-durch-server-abwaerme.html http://www.energiesparhaushalt.de/1/intelligent-heizen-durch... It looks like they didn't got much interest in the market and pivoted more to industrial customers. The main purpose now is not a computer node as a heating, but instead recovering the waste heat from computer rack for the heating system.

74 points by btdmaster 4y ago

I wonder if you could do this yourself with a heat exchange (like from McMaster-Carr). I've read before that if you run the loops "backwards", such that the two loops of the heat exchanger are flowing in opposite directions, that you can increase the rate of heat transfer by maximizing the difference in temperature. Has anybody done this before?

oakwhiz 4y ago
That's the normal way to do it and it's part of the reason why many devices label the supply and return fittings.
smileysteve 4y ago
If i were running a mining rig, that's how i would do it.
cypherpunks01 4y ago
This is called a counter-flow heat exchanger or countercurrent exchange, it's very commonly used in industrial applications, for both gas or fluid flow. This setup is very efficient at heat transfer, and can counter-intuitively produce a higher output temperature than the counterflow's input temperature. https://en.wikipedia.org/wiki/Countercurrent_exchange https://en.wikipedia.org/wiki/Countercurrent_exchange

whalesalad 4y ago

very clever but I wonder what kind of workloads are being run on these remote/edge compute nodes. there isn't any homogeneity in the network - everyone is going to be on a different kind of network with a huge variations in bandwidth and latency. can't find any specs on what kind of compute power each physical installation would provide

colobas 4y ago
These guys [1] used to be called Nerdalize and iirc their first iteration looked a lot like this. I think they have since moved to a model of a few select locations where nodes are closer to each other. [1] - https://www.leaf.cloud https://www.leaf.cloud EDIT: fixed link
smileysteve 4y ago
Most simply it could be used for crypto mining (except the utility would have to upgrade the hardware very often)
- imhoguy 4y ago
  The compute rig would need to be the size of the water tank to make the business even. Maintenance cost would be much higher too. Better to keep all compute in house sized DC units and just sell hot water to neighbors.
bob1029 4y ago
Some workloads I can think of beyond crypto cases: Distributed compilation of large code bases, offline rendering, baking lighting for AAA, media transcoding. Basically, anything batch-style that doesn't demand reliable latency and can tolerate some amount of failure in the cluster.

sammoe13 4y ago

Doing some back of the napkin math, their contractual minimum of 2.5 kWh a day into your water heater works out to 75 kWh a month. This [1] site claims the average two person home uses 195 kWh a month, so it potentially could be a decent offset. I do wonder whether this quoted 2.5 kWh is energy coming off the server into your heater, or if it's measured somewhere else. Energy loss from thermal transfer would make a huge difference in measured input into your heating system. [1] https://www.keysenergy.com/typical-electric-usage-of-various-appliances/ https://www.keysenergy.com/typical-electric-usage-of-various...

post_break 4y ago
Where are they getting 195 kWh a month? That's crazy low. Even when I don't need to run the AC or heat I'm in the 800's.
- sammoe13 4y ago
  Sorry, I should have made it clear that I was referring only to an average two-person home's energy use for creating hot water monthly.

Alupis 4y ago

I'm highly skeptical this thing can provide enough heat energy to warm an entire water tank and keep it warm for the sporadic on-demand loads a hot water tank typically endures. Will it take 3 days to warm back up after a moderately long hot shower while simultaneously running the dishwasher? I'm further skeptical at the claim of a dedicated fiber line being installed just for this server (having been on the receiving side of fiber install quotes with 5-6 digits) - and even more skeptical at the claim of using 4G/5G connections for servers. I'll believe it when I see it... but it reads like it was written by someone that really doesn't have a grasp of what we're dealing with here.

smileysteve 4y ago
You may want to re-read; this isn't disabling the current water heater, it is modifying it to be less insulated, and placing a compute unit there. [It will maintain an immersion heater] Re: fiber, Natural gas lines often already have a fiber line for monitoring (some US utils were the first to the fiber market because of this)
- Alupis 4y ago
  The cost of routing a fiber line is extraordinary. Even if one existed nearby, it would not be usable because it's owned by the utility not this private server company. Regarding keeping the existing heating element - seems necessary because this server water heater isn't going to heat much of anything. To flip it on it's head - this is free cooling capacity for a for-profit server company that will do little-to-zero for the home owner and risks damaging their expensive water heater for some hand-wavy promised savings of $200 a year... not really selling me.
  - smileysteve 4y ago
    Which is more difficult, routing a fiber line or a natural gas line?
    - deleted 4y ago
      [deleted]

smileysteve 4y ago

Natural Gas companies near me began offering fiber services before Google Fiber did; because they had the infrastructure to monitor the lines and distribution nodes; Given that fiber setup, the gas company has a low latency network.

smileysteve 4y ago

This along with the increase in heat pumps, really makes me question air source heat pumps not directly hybridizing with water heaters (new water heaters have heat pumps that will cool your utility closet). But using house heat pumps to cool air / heat water in the summer could at least decrease energy use during the day; and then in the winter, the water (as a heat source) can help assist older heat pumps in pumping heat from the cold (though modern heat pumps solve this problem)

blamazon 4y ago

This could be flipped - I.e. using a Japanese domestic fuel cell[1] one could install a hot water heater in the home, and get 'free' electricity to run a server, that could possibly do something productive to offset the associated capital and operational expenditures. [1] https://www.j-lpgas.gr.jp/en/appliances/ https://www.j-lpgas.gr.jp/en/appliances/ (Interesting aside: some people in Japan combine these with a solar/battery array to achieve robust all-season off grid self sufficiency, without combustion, which I think is quite neat!)

blacksmith_tb 4y ago
True, though it'd be using propane / LP gas, where the server-cooled-by-heating-your-water could potentially be powered by electricity from solar or wind...
- deleted 4y ago
  [deleted]

Havoc 4y ago

Quite surprised that they’re running that off 4G I’ve found tech driven heating to work quite well though. For small apartments you really don’t need all that much output if it’s 24/7

mike-cardwell 4y ago
They're not running it off 4G. Click through to the trial and read the FAQ. It's using your home broadband connection.
- Havoc 4y ago
  So the article is wrong? > the answer is no, as we are told the server uses its own connection which will either be its own dedicated fiber line or a 4G/5G connection.
  - mike-cardwell 4y ago
    Yes

mabbo 4y ago

Worth remembering that you don't need the server to completely heat the water to shower temperature. You can get it part way there, and then it will take less heat to get the water heater the rest of the way. I could imagine a future where every house has something like this partially heating their water and air before the real heating system is applied.

thatwasunusual 4y ago
> I could imagine a future where every house has something like this partially heating their water and air before the real heating system is applied. This is really important. Where I live - Oslo, Norway - we have a sun thermal collector-thingy[0] on the roof which _aids_ in heating up other stuff. Surely, it needs to be a fire nearby to heat the water enough to have a comfortable shower, but we save approx. $20K yearly[1] on energy costs with this solution. [0] https://en.wikipedia.org/wiki/Solar_thermal_collector https://en.wikipedia.org/wiki/Solar_thermal_collector [1] I live in a housing association with 60 other families in the same building, so needless to say the savings would be a lot less if I lived on my own in one house. :)
imhoguy 4y ago
This is why placing server pretty much anywhere in the well insulated house during cold months contributes to overall heat sum. The only problem is in hot months where that extra heat needs to be removed from the living space. Some inner house heat pump solution could collect that air heat and concentrate it in the water tank.
- mabbo 4y ago
  Isn't that what this product is doing though?

out-of-ideas 4y ago

title might as well say: get a job, get dollar bills for free!

tonymet 4y ago

in eastern europe they pump hot water directly to homes . it’s waste water from nearby power stations . you could do the same from the data center to homes

Symbiote 4y ago
Facebook does exactly that in Odense, Denmark. https://sustainability.fb.com/wp-content/uploads/2020/12/FB_Denmark-Data-Center-to-Warm-Local-Community.pdf https://sustainability.fb.com/wp-content/uploads/2020/12/FB_...
william_T 4y ago
most datacenter's will recycle their water. Heat it up, send it somewhere else to cool down, send it back to heat up. Specific datacenters were called out on here last week for dumping heat waste water. The efficiency of moving hot water over long distances doesnt make much sense
- tonymet 4y ago
  my point is that it's commonly used e.g. in Finland & Russia, so someone has figured out how to get hot water from outside the city into the city and heat homes.

tombert 4y ago

Somewhat tangential, but in my first NYC apartment, our radiator was absolutely terrible, and did a miserable job getting the living room to an even remotely livable temperature. My solution? Two giant rack mount servers, running Foldign@Home at full capacity. Way I figured is that it's still 100% efficient at generating heat, but I might as well help drug research in the process.

imhoguy 4y ago
Just curious, how have you handled the noise?
- mhb 4y ago
  And the electric bill.
- tombert 4y ago
  We don’t live there anymore, so we don’t, but we honestly just put up with it. I don’t have any pointers on that fact. To the child comment; I’ve told this story in the past but the tldr of it was that I was (unknowingly) not paying for the electricity in my apartment due to a broken meter. I didn’t break it, and I didn’t know it was broken; I just thought power was really cheap in NYC.
compsciphd 4y ago
that's the opposite problem that most people (from my experience) have in NYC. Apartments get too much heat (i.e. landlords can get seriously fined if they dont keep the building at a proper temp, so its just easier and safer for them to give too much heat). Also, many radiators in old buildings aren't really adjustable anymore (and hence you get all the heat). so its common for people in NYC to keep their windows open in the middle of winter to try to balance out the temperature.
- ljnelson 4y ago
  Interestingly, this is often by design: https://www.npr.org/2020/12/10/945136599/how-spanish-flu-pandemic-changed-home-heat-radiators#:~:text=CHANG%3A%20This%20design%20philosophy%20took,from%20coal%20to%20other%20fuels https://www.npr.org/2020/12/10/945136599/how-spanish-flu-pan....

tobyhinloopen 4y ago

I wonder if I can use my water cooled PC to heat water for the shower

amelius 4y ago

What if you go on a trip and don't use hot water for a couple of days?

mike-cardwell 4y ago
From the FAQ on the trial page, it seems like it will simply not run if there is nowhere to dump the excess heat: How much of my hot water will it deliver? A useful base load. If the heata unit ran all day it would deliver about 4.8kWh of hot water which is about the amount of hot water an average household uses. In practice the utilisation level will be lower and sometimes the water will be at temperature so the heata unit won't be able to run. We think it could deliver up to 80% of an average household's hot water, with good compute utilisation. This trial will help us learn more about how this will work in practice and enable us to give you a useful amount of free hot water at the same time.

nfcampos 4y ago

So what do people do with these things in summer? Won’t it then heat up their house excessively

mike-cardwell 4y ago
Open a window?
indigomm 4y ago
It heats the water tank, just as people heat their water tanks now in the summer. No difference really, except some of that energy is free to the homeowner.

LargoLasskhyfv 4y ago

Prior art: https://qarnot.com/en https://qarnot.com/en https://www.leaf.cloud/ https://www.leaf.cloud/ https://www.cloudandheat.com/ https://www.cloudandheat.com/ I wonder how that worked out, given the development of energy prices...

hommelix 4y ago

In Germany the startup that became Cloud&Heat Technologies started with the idea to sell a heating system for home powered by some computers. It seems that they have pivoted to sell 19" rack with water cooling that can be connected to a building heating system, more for companies than individual household. https://www.cloudandheat.com/ https://www.cloudandheat.com/ Here is an article from 2020 in German presenting the computer rack as a heating system. http://www.energiesparhaushalt.de/1/intelligent-heizen-durch-server-abwaerme.html http://www.energiesparhaushalt.de/1/intelligent-heizen-durch... It looks like they didn't got much interest in the market and pivoted more to industrial customers. The main purpose now is not a computer node as a heating, but instead recovering the waste heat from computer rack for the heating system.