4 ms·

> produces 3 kW to 4 kW of heat for every kilowatt of power it consumes So, not too different from typical heat pumps. Ground-source heat pumps are especially

> produces 3 kW to 4 kW of heat for every kilowatt of power it consumes So, not too different from typical heat pumps. Ground-source heat pumps are especially effective.

tecleandor 4y ago
Although it feels like a nice value for a first model in the market. I find interesting that's very silent, and has a nice range of work temperatures. And the "no refrigerants" part too (although it needs some helium, though). No info about the price.
nraynaud 4y ago
funny, I read the same thing, and had the optimistic view that maybe this is not a scam, they are not claiming crazy numbers. I suppose that since scientific machines use this apparatus, their design space has been explored in great details.
- kibwen 4y ago
  I remember reading about thermoacoustic devices 20 years ago, probably from the following article: https://www.popsci.com/scitech/article/2004-05/chilling-sound-waves-not-freon/ https://www.popsci.com/scitech/article/2004-05/chilling-soun... I think the reason that they haven't seen adoption isn't that they're a scam, but rather because they're more expensive than traditional approaches (not quite sure why, or by what margins). However, since our attempts to replace freon with ever-more-exotic refrigerants seems to inevitably fall face-first into environmental disaster, it's possible that a non-greenhouse-gas approach could be regulated/subsidized into existence, if it's not too much more expensive.
speleding 4y ago
> hot water at temperatures of up to 80 ℃ > level of noise is reportedly lower than 30 dB If it can provide water hot enough for residential use, and be silent, then it's a huge improvement over existing typical heat pumps. It would no longer need an additional boiler to get the water temperature up.
was_a_dev 4y ago
Isn't this working at a significantly higher ouput temperature? Typical heat pumps are nowhere near COP 4.0 when outputting 80C (about 60C delta)
- IanCal 4y ago
  They don't, as far as I can tell, claim that. There is a claim of SCOP of 3-4, and a claim that they can output 80C, but there isn't a claim they can output 80C at a SCOP of 3-4.
  - was_a_dev 4y ago
    Good point. It had slipped past me. The latter definitely is more plausible
chpatrick 4y ago
You can't install a ground-source heat pump in the middle of the city.
- _0w8t 4y ago
  In Scandinavia this is routinely done via boring very deep wells, like 300m, https://hvac.okstate.edu/sites/default/files/pubs/papers/2016/Gehlin_Spitler_Hellstr%C3%B6m_2016_Deep_BH.pdf https://hvac.okstate.edu/sites/default/files/pubs/papers/201... This may not be suitable for skyscrapers, but it works for 4-5 store apartment blocks.
- cjrp 4y ago
  Under a parking lot?
  - 8bitsrule 4y ago
    Could be in a building's basement too.
redleader55 4y ago
This sounds a bit puzzling to me, so probably I'm missing something. 1 kW of electricity (eg. 200V at ~5A) turns into 3 kW of heat. It would mean we are creating "work" from nothing, which sounds impossible to me. How does that work in fact?
- cjrp 4y ago
  Don't think of it as creating 3kW of heat, think of it as using the electricity to transfer that much heat.
- 0x5345414e 4y ago
  COP vs. efficiency. In the case of a heat pump, it takes 1 kW to “move” 3 kW of heat, rather than turning 1 kW into 3 kW.
- alsaaro 4y ago
  Its pumping heat from its the "outside", as you know heat flows from hot to cold, and the gas in this case (uncompressed helium), is colder than the outside, absorbing heat from the outside.
dagss 4y ago
For typical heatpumps efficiency is a factor of temperature difference. Ground-source are efficient (COP 5) because you go from 5 degrees Celsius to perhaps 35 degree Celsius (underfloor heating or low temperature convection radiators) This invention claims COP 4 for heating water to 80 degrees, that is a huge step up. For instance it changes the game to replace oil and gas heated radiators, as you can only replace the heat source, not radiators that only work well with 80 deg C water (where COP is very bad for conventional heat pumps)

> produces 3 kW to 4 kW of heat for every kilowatt of power it consumes So, not too different from typical heat pumps. Ground-source heat pumps are especially effective.

tecleandor 4y ago

Although it feels like a nice value for a first model in the market. I find interesting that's very silent, and has a nice range of work temperatures. And the "no refrigerants" part too (although it needs some helium, though). No info about the price.

nraynaud 4y ago

funny, I read the same thing, and had the optimistic view that maybe this is not a scam, they are not claiming crazy numbers. I suppose that since scientific machines use this apparatus, their design space has been explored in great details.

kibwen 4y ago
I remember reading about thermoacoustic devices 20 years ago, probably from the following article: https://www.popsci.com/scitech/article/2004-05/chilling-sound-waves-not-freon/ https://www.popsci.com/scitech/article/2004-05/chilling-soun... I think the reason that they haven't seen adoption isn't that they're a scam, but rather because they're more expensive than traditional approaches (not quite sure why, or by what margins). However, since our attempts to replace freon with ever-more-exotic refrigerants seems to inevitably fall face-first into environmental disaster, it's possible that a non-greenhouse-gas approach could be regulated/subsidized into existence, if it's not too much more expensive.

speleding 4y ago

> hot water at temperatures of up to 80 ℃ > level of noise is reportedly lower than 30 dB If it can provide water hot enough for residential use, and be silent, then it's a huge improvement over existing typical heat pumps. It would no longer need an additional boiler to get the water temperature up.

was_a_dev 4y ago

Isn't this working at a significantly higher ouput temperature? Typical heat pumps are nowhere near COP 4.0 when outputting 80C (about 60C delta)

IanCal 4y ago
They don't, as far as I can tell, claim that. There is a claim of SCOP of 3-4, and a claim that they can output 80C, but there isn't a claim they can output 80C at a SCOP of 3-4.
- was_a_dev 4y ago
  Good point. It had slipped past me. The latter definitely is more plausible

chpatrick 4y ago

You can't install a ground-source heat pump in the middle of the city.

_0w8t 4y ago
In Scandinavia this is routinely done via boring very deep wells, like 300m, https://hvac.okstate.edu/sites/default/files/pubs/papers/2016/Gehlin_Spitler_Hellstr%C3%B6m_2016_Deep_BH.pdf https://hvac.okstate.edu/sites/default/files/pubs/papers/201... This may not be suitable for skyscrapers, but it works for 4-5 store apartment blocks.
cjrp 4y ago
Under a parking lot?
- 8bitsrule 4y ago
  Could be in a building's basement too.

redleader55 4y ago

This sounds a bit puzzling to me, so probably I'm missing something. 1 kW of electricity (eg. 200V at ~5A) turns into 3 kW of heat. It would mean we are creating "work" from nothing, which sounds impossible to me. How does that work in fact?

cjrp 4y ago
Don't think of it as creating 3kW of heat, think of it as using the electricity to transfer that much heat.
0x5345414e 4y ago
COP vs. efficiency. In the case of a heat pump, it takes 1 kW to “move” 3 kW of heat, rather than turning 1 kW into 3 kW.
alsaaro 4y ago
Its pumping heat from its the "outside", as you know heat flows from hot to cold, and the gas in this case (uncompressed helium), is colder than the outside, absorbing heat from the outside.

dagss 4y ago

For typical heatpumps efficiency is a factor of temperature difference. Ground-source are efficient (COP 5) because you go from 5 degrees Celsius to perhaps 35 degree Celsius (underfloor heating or low temperature convection radiators) This invention claims COP 4 for heating water to 80 degrees, that is a huge step up. For instance it changes the game to replace oil and gas heated radiators, as you can only replace the heat source, not radiators that only work well with 80 deg C water (where COP is very bad for conventional heat pumps)