3 ms·

According to the efficiency of the device?

caf 11y ago
The heating efficiency has to be 100%, because the electricity isn't being converted into any other energy form. (That's still worse than an electric heat pump though, though - those have > 100% heating efficiency in terms of electricity input).
- jsprogrammer 11y ago
  Everything above 0K will emit photons, no?
  - pmalynin 11y ago
    Right, but at those temperature the photons have near infrared frequency, hence they won't escape your house and simply heat it
    - ori_b 11y ago
      There will also be plenty of RF interference, although that's at a lower energy, and therefore will use less energy to produce.
- wlesieutre 11y ago
  > (That's still worse than an electric heat pump though, though - those have > 100% heating efficiency in terms of electricity input). "Coefficient of Performance" being the over-100%-not-technically-efficiency measure for heat pumps. [0] Or "Seasonal Energy Efficiency Ratio" if for god knows what reason you want to measure it in British thermal units per Watt hour. [1] So a setup like this isn't actually competitive with a heat pump in most conditions, but if the electricity was going to be burned in a datacenter anyway you might as well use the heat for something productive. https://en.wikipedia.org/wiki/Coefficient_of_performance https://en.wikipedia.org/wiki/Coefficient_of_performance https://en.wikipedia.org/wiki/Seasonal_energy_efficiency_ratio https://en.wikipedia.org/wiki/Seasonal_energy_efficiency_rat...
- gusmd 11y ago
  If I understood it correctly, there is a server running inside that thing. So by definition, all the heat being generated is inefficiency. Therefore, if 1000 W are being disposed as heat to the environment, then the machine itself is consuming WAY more than that. Otherwise, they found a way to do computing without consuming any energy. edit: Upon further googling, it looks like I was stupid here. So almost all energy consumed by a PC is dissipated as heat? Did not know that, sorry.
  - deleted 11y ago
    [deleted]
  - caf 11y ago
    So almost all energy consumed by a PC is dissipated as heat? Yes. The other forms of energy leaving your PC range from tiny to infintesimal: light from the keyboard/case LEDs, kinetic energy in the exhaust air molecules, radiated RF (both intentional like WiFi and unintentional), radiated sound (both intentional from inbuilt speakers or connected headphones and unintentional from vibrating components), earth leakage, and resistance losses in external wired network connections. Most of these forms are then reabsorbed and converted to heat by other objects in the immediate surroundings as well. Increases in the energy stored within the PC are entirely dominated by temperature increases (which will equalise with the surroundings over time). There would also be a truly infintesimal amount of energy stored in changed potential energy in magnetic domains on your hard disk or stored charges in your SSD.
    - gusmd 11y ago
      Yes, I get it. Being a Mechanical Engineer and used to balancing energy in heat engines, I just (incorrectly) assumed that SOME kind of work was being done by the computer to perform its main function, which is obviously not the case (at least not to non-negligible amounts). Thanks for clarifying.
      - caf 11y ago
        Ahh, as an ME you would appreciate then that the useful work a computer does is not thermodynamic work but a decrease in the disorder of some system it is a part of, and this necessarily requires increasing the entropy of its environment - typically by transferring heat to it!
- pervycreeper 11y ago
  Some energy (but not much!) goes out through the network.

caf 11y ago

The heating efficiency has to be 100%, because the electricity isn't being converted into any other energy form. (That's still worse than an electric heat pump though, though - those have > 100% heating efficiency in terms of electricity input).

jsprogrammer 11y ago
Everything above 0K will emit photons, no?
- pmalynin 11y ago
  Right, but at those temperature the photons have near infrared frequency, hence they won't escape your house and simply heat it
  - ori_b 11y ago
    There will also be plenty of RF interference, although that's at a lower energy, and therefore will use less energy to produce.
wlesieutre 11y ago
> (That's still worse than an electric heat pump though, though - those have > 100% heating efficiency in terms of electricity input). "Coefficient of Performance" being the over-100%-not-technically-efficiency measure for heat pumps. [0] Or "Seasonal Energy Efficiency Ratio" if for god knows what reason you want to measure it in British thermal units per Watt hour. [1] So a setup like this isn't actually competitive with a heat pump in most conditions, but if the electricity was going to be burned in a datacenter anyway you might as well use the heat for something productive. https://en.wikipedia.org/wiki/Coefficient_of_performance https://en.wikipedia.org/wiki/Coefficient_of_performance https://en.wikipedia.org/wiki/Seasonal_energy_efficiency_ratio https://en.wikipedia.org/wiki/Seasonal_energy_efficiency_rat...
gusmd 11y ago
If I understood it correctly, there is a server running inside that thing. So by definition, all the heat being generated is inefficiency. Therefore, if 1000 W are being disposed as heat to the environment, then the machine itself is consuming WAY more than that. Otherwise, they found a way to do computing without consuming any energy. edit: Upon further googling, it looks like I was stupid here. So almost all energy consumed by a PC is dissipated as heat? Did not know that, sorry.
- deleted 11y ago
  [deleted]
- caf 11y ago
  So almost all energy consumed by a PC is dissipated as heat? Yes. The other forms of energy leaving your PC range from tiny to infintesimal: light from the keyboard/case LEDs, kinetic energy in the exhaust air molecules, radiated RF (both intentional like WiFi and unintentional), radiated sound (both intentional from inbuilt speakers or connected headphones and unintentional from vibrating components), earth leakage, and resistance losses in external wired network connections. Most of these forms are then reabsorbed and converted to heat by other objects in the immediate surroundings as well. Increases in the energy stored within the PC are entirely dominated by temperature increases (which will equalise with the surroundings over time). There would also be a truly infintesimal amount of energy stored in changed potential energy in magnetic domains on your hard disk or stored charges in your SSD.
  - gusmd 11y ago
    Yes, I get it. Being a Mechanical Engineer and used to balancing energy in heat engines, I just (incorrectly) assumed that SOME kind of work was being done by the computer to perform its main function, which is obviously not the case (at least not to non-negligible amounts). Thanks for clarifying.
    - caf 11y ago
      Ahh, as an ME you would appreciate then that the useful work a computer does is not thermodynamic work but a decrease in the disorder of some system it is a part of, and this necessarily requires increasing the entropy of its environment - typically by transferring heat to it!
pervycreeper 11y ago
Some energy (but not much!) goes out through the network.