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Scientists Just Broke the Solar Power Limit Everyone Thought Was Absolute

39 points by g-b-r ago | 16 comments

telegtron |next [-]

"... if your theory is found to be against the second law of thermodynamics I can give you no hope; there is nothing for it but to collapse in deepest humiliation."

Sir Arthur Eddington

gus_massa |root |parent [-]

It looks like they don't claim to break the second law of thermodynamics, but the press article is so bad that any interpretation is possible. IIUC in the research article they just got "quantum efficiency" of 130% i.e. 1.3 electrons per 1 photon. This may improve the energetic efficiency, but I can't be sure from the details. It loos like a weird setup disolved in a liquid, so I guess it's still less efficient than a usual photovoltaic cell.

ternus |next |previous [-]

> This method achieved an energy conversion efficiency of about 130%, exceeding the traditional 100% limit

I am extraordinarily confident that it did not.

> In practical terms, this means about 1.3 molybdenum-based metal complexes were activated for every photon absorbed, surpassing the conventional limit and demonstrating that more energy carriers were generated than incoming photons.

... Which is not the same thing as a >100% energy conversion efficiency (which would imply an infinite-energy-generating pump)

esperent |root |parent |next [-]

The theoretical maximum efficiency for solar panels is ~33% total energy conversion. So I assume what they mean here is that they achieved 130% of 33% =~43% total energy conversion, which doesn't break any laws of physics.

That said, I read the article and it's very unclear. They talk about 130% quantum efficiency but I have no idea what that might mean.

g-b-r |root |parent |previous [-]

True ;)

g-b-r |root |parent [-]

The 130% seems to be the quantum yield

metalman |next |previous [-]

The "absolutre efficiency" limit has been moved before.used to be 17% tripple junction and other exotic panels have been getting up to 50%+- efficiency, but the standerdised efficiency limit of 33% conversion of solar energy is for single junction conventional panels. Suggestion here is for 45% +- conversion of solar to electricity, so 450w/m², 20m²/18kw, and of course as this is capturing infrared energy, there would be residual generation at night. The demand from aerospace will drive earlier development, but as there will be other solutions, not that there are results, research happening everywhere will shift. edit: has shifted

dmitrygr |next |previous [-]

> achieved an energy conversion efficiency of about 130%

No it did not. Please find a science correspondent who at least passed high school physics.

bcraven |root |parent [-]

I often think this at first when I see such numbers, but then remember that condensing boilers have efficiencies over 100% so then I'm not sure.

dns_snek |root |parent |next [-]

It's just a trick. The methodology used to arrive at >100% numbers doesn't actually consider all of the caloric energy in the fuel. The difference between higher and lower heating value of methane is about 10% and condensing boilers are usually marketed as 107% efficient.

The gist of it is that the fuel might contain 1 kWh of chemical energy but 0.1 kWh was traditionally lost to water vaporization during combustion, so they start with a denominator of 0.9kWh and since condensing boilers capture this "lost" energy through condensation it leaves you with >100% efficiency, on a technicality. No laws of physics are being violated.

dzhiurgis |root |parent |previous [-]

Just need to pump energy from anti-matter, simple!

hulitu |next |previous [-]

> Everyone Thought Was Absolute By Kyushu University

I was expecting such a "dogma" from a catholic university. But from a Japanese one ? What happened to critical thinking ? Has been left to AI ?

muhdeeb |previous [-]

So it seems that their definition of 100% means 1 excited state per incoming photon, and then they use a material that converts a single high energy excited state produced by one photon into 2 half as energetic excited states...but then they apply the definition that just counts any excited state per incoming photon to juice their numbers.

So more like 65% energy conversion efficiency at best.

vi_sextus_vi |root |parent |next [-]

Useful idea buried under abject science-writing is that

quantum yields quantify how likely a chain reaction is. It's like r for COVID-19. One usually says "1.3", not "130%"

Quantum yields greater than 1 are possible for photo-induced or radiation-induced chain reactions, in which a single photon may trigger a long chain of transformations

https://en.wikipedia.org/wiki/Quantum_yield#:~:text=Quantum%...

Diagram from the paper showing the initiation of a light-generated "avalanche"

https://xcancel.com/YoichiSasaki1/status/2036808566011789536

aitchnyu |root |parent |previous [-]

How did you calculate the radiation joules -> electricity joules efficiency when the scientists apparently did not?