Competition for fridges and heat pumps: Thermogalvanic cell is three times more efficient

[Redaktion]

No compressor, no displacement, no thermodynamic cycle. Researchers have found a method that could make cooling and heating much more efficient.

https://www.notebookcheck.net/Competition-for-fridges-and-heat-pumps-Thermogalvanic-cell-is-three-times-more-efficient.958336.0.html

[heffeque]

If true... it's great news. Yet another reason to change natural gas, etc. for efficient electric climate control.

Personally really happy with my heat pump. It heats water and keeps my home's temperature perfect with very very little power (so low monthly spending).

[tR0y2020]

3 times more efficient? So it's 1200% efficient? Highly doubt that. Heat pumps are 400% efficient. Please fact check before posting.

[heffeque]

3 times more efficient? So it's 1200% efficient? Highly doubt that. Heat pumps are 400% efficient. Please fact check before posting.

More like 300% for heat pumps in real scenarios, so 900% for whatever this is but... I also doubt it too. Either way, let's give them the benefit of the doubt!

[Donovan]

It's coefficient of performance, not efficiency. He literally writes it has a COP of 14.2, so yes 1,420% to be more precise.

I'm confused as to where your skepticism comes from. Does it just sound like a high number to you?

You come off as extremely presumptuous of the validity of the article without having anything to say to the contrary other than 'that number looks too big.'

[Donovan]

3 times more efficient? So it's 1200% efficient? Highly doubt that. Heat pumps are 400% efficient. Please fact check before posting.

It's coefficient of performance, not efficiency. He literally writes it has a COP of 14.2, so yes 1,420% to be more precise.

I'm confused as to where your skepticism comes from. Does it just sound like a high number to you?

You come off as extremely presumptuous of the validity of the article without having anything to say to the contrary other than 'that number looks too big.'

[heffeque]

Well... the number does look "too big". But if true and not too expensive, than it's a very welcome technology!

[RangMake]

In my experience, rust has almost always been a one way street. But what do I know?

[A]

In my experience, rust has almost always been a one way street. But what do I know?

Rust isn't always been a one way street, I mean how do you think Rust Air batteries work? By creating rust and reversing it.

[LARPArchitect]

3 times more efficient? So it's 1200% efficient? Highly doubt that. Heat pumps are 400% efficient. Please fact check before posting.

More like 300% for heat pumps in real scenarios, so 900% for whatever this is but... I also doubt it too. Either way, let's give them the benefit of the doubt!

It's been cold here the last week and my heat pump has achieved a COP of 4.0 (400%) for combined heating and hot water.

That is my real scenario. And my system is a retro-fit so it is certainly possible to achieve even higher efficiency.

I did take a snapshot of the data in my Vaillant app, but the forum won't let me share links.

[anan]

Does this method use electrolytic rust removal? Aren't there consumables involved and gasses generated?
Or did they find a method to create a closed loop cycle?

[Don]

It literally works by rusting iron and reversing the process.  It's a thermal battery, not a thermal transferring process.  The limited storage capacity makes it inappropriate for almost all HVAC, refrigeration, or other relatively continuous applications.

[William Gardiner]

The best COP that can be achieved is related to the Carnot thermal efficiency. See wikipedia "Thermal Efficiency", for example.

If the source of heat is 273K (freezing) and the sink is 318K (heat pump flow temperature of 45C) then the limiting COP value is 318/(318-273) = 7. This is the ideal value - it can never be achieved. A COP value of 4, as commonly achieved in practice, is respectable, suggesting an overall system efficiency of 4/7 or 57%.

However, a claimed COP of 14 breaks fundamental laws of physics. The article does not state what the two temperatures were (source and sink), but if very close, then a high COP figure would be possible, although not very useful. It is a pity that the article does not supply this information.

A semiconductor heat pump would reduce the amount of moving parts, but the source and sink would still need fans and circulators to work.

It is an interesting article, but the headline claims discredit the research, which is a pity.

[Oto]

Wuhan?
No thanks.