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New Material Breaks World Record Turning Heat into Electricity

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Re: New Material Breaks World Record Turning Heat into Electricity

#101

Post by justAnotherNET »

pharke wrote: post #97

If an advanced civilization continued to improve the efficiency of this effect would they eventually use it to capture the majority of the energy output of their local star? You could have a shell of high efficiency solar satellites surrounded by another shell of high efficiency Seebeck satellites. What would this look like from a distance? Would they be able to capture enough energy so their star would be indistingu…

This is both horrific and fascinating. I’ve never even considered that option as an answer to “dark matter”/unexplained mass.

Re: New Material Breaks World Record Turning Heat into Electricity

#102

Post by [deleted] »

pharke wrote: post #97

If an advanced civilization continued to improve the efficiency of this effect would they eventually use it to capture the majority of the energy output of their local star? You could have a shell of high efficiency solar satellites surrounded by another shell of high efficiency Seebeck satellites. What would this look like from a distance? Would they be able to capture enough energy so their star would be indistingu…

[deleted]

Re: New Material Breaks World Record Turning Heat into Electricity

#104

Post by bagacrap »

pharke wrote: post #97

If an advanced civilization continued to improve the efficiency of this effect would they eventually use it to capture the majority of the energy output of their local star? You could have a shell of high efficiency solar satellites surrounded by another shell of high efficiency Seebeck satellites. What would this look like from a distance? Would they be able to capture enough energy so their star would be indistingu…

What would they use all that energy for, and how would they use it in a way that wouldn't radiate heat or light on par with the amount captured?

Re: New Material Breaks World Record Turning Heat into Electricity

#105

Post by lopmotr »

ailideex wrote: post #98

// Removed as I'm not a physicist and may be mistaken.

I think it's correct. Heat is the flow of thermal energy. A portion of that flowing energy is converted to electrical energy. Perhaps you're confusing heat with thermal energy?

There must be some heat flowing to generate electrical power because of the 1st law, so even if the effect is described as being due to a temperature difference, in practice, you also need a heat flow to be useful.

Your quote about "without any side effect" means without heating up a cold reservoir. But the article doesn't claim that.

Re: New Material Breaks World Record Turning Heat into Electricity

#106

Post by ailideex »

pharke wrote: post #97

If an advanced civilization continued to improve the efficiency of this effect would they eventually use it to capture the majority of the energy output of their local star? You could have a shell of high efficiency solar satellites surrounded by another shell of high efficiency Seebeck satellites. What would this look like from a distance? Would they be able to capture enough energy so their star would be indistingu…

> Would they be able to capture enough energy so their star would be indistinguishable from the ambient temperature of space?

You would still see infrared:

https://en.wikipedia.org/wiki/Fermi_paradox#Conjectures_abou...

> Such a feat of astroengineering would drastically alter the observed spectrum of the star involved, changing it at least partly from the normal emission lines of a natural stellar atmosphere to those of black-body radiation, probably with a peak in the infrared.

https://en.wikipedia.org/wiki/Technosignature

> A Dyson sphere, constructed by life forms dwelling in proximity to a Sun-like star, would cause an increase in the amount of infrared radiation in the star system's emitted spectrum. Hence, Freeman Dyson selected the title "Search for Artificial Stellar Sources of Infrared Radiation" for his 1960 paper on the subject.[4] SETI has adopted these assumptions in its search, looking for such "infrared heavy" spectra from solar analogs. From 2005, Fermilab has conducted an ongoing survey for such spectra, analyzing data from the Infrared Astronomical Satellite.[5][6]

Re: New Material Breaks World Record Turning Heat into Electricity

#107

Post by zbrozek »

lopmotr wrote: post #105
ailideex wrote: post #98

// Removed as I'm not a physicist and may be mistaken.

I think it's correct. Heat is the flow of thermal energy. A portion of that flowing energy is converted to electrical energy. Perhaps you're confusing heat with thermal energy? There must be some heat flowing to generate electrical power because of the 1st law, so even if the effect is described as being due to a temperature difference, in practice, you also need a heat flow to be useful. Your quote about "without an…

Heat is the energy, not the flow. That flow is flux or power. A temperature difference is how we perceive or measure a difference in thermal energy density between two places, and is the potential that drives heat flux. A thermoelectric barrier between those two wells can extract energy from that flow, within thermodynamic limits.

Re: New Material Breaks World Record Turning Heat into Electricity

#108

Post by asdfman123 »

dghughes wrote: post #95
grecy wrote: post #64

I've always wanted to build a little hobby project where I put TECs on top of my wood stove and have a radiator outside with coolant to get a nice big heat difference (maybe 100C to 200C) across them and make power in winter when solar isn't so great in the Yukon. I know it won't be a massive amount of power, but given it will be 24/7 for about 6 months of winter when the wood stove runs, I think it will be a useful…

Hello fellow Canadian :) Wouldn't a home made Sterling Engine be easier and cheaper? Then use the motion to power a small generator. But like others commented you may just end up cooling your stove. The Yukon can get pretty cool. Maybe an old washer motor, a prop to generate power from wind? Or solar in the summer when light is ample.

Yeah, I've seen people who use small wind turbines to generate electricity far north. Seems like the best way to do it.

Re: New Material Breaks World Record Turning Heat into Electricity

#109

Post by lgats »

grecy wrote: post #96
esotericn wrote: post #74

Earlier quoted context omitted.

Won't this reduce the thermal output of your stove quite significantly? I suppose that might not be a problem in practice (most wood stoves I've used end up overheating the room if you're not careful), but it's not like it's free energy :P

> Won't this reduce the thermal output of your stove quite significantly I'm going to chime in and say that I think it will be insignificant. I don't know for sure, but I really doubt you could do much to cool the stove. When it's cold in the Yukon, I'm literally stuffing in ~8-10 big logs every ~12 hours. It's not at all uncommon for the base of the chimney to be glowing red. Obviously not ideal, but it happens. Whe…

I think you could build a panel of TECs and just set it up near your wood stove. The radient hear from the stove would be enough to keep the TECs at high temp on one side and room temp (maybe with some heatsink) on the other side.

You could adjust the distance from the stove to keep things within operating range.

Re: New Material Breaks World Record Turning Heat into Electricity

#110

Post by lopmotr »

icris wrote: post #38

does this imply an overall entropy reduction for a whole system comprising a device and support apparatus for reusing its heat as energy source supply?

Are you asking if it violates the 2nd law? Of course not.

It's just a heat engine like any other electrical generator so it's not going to have fundamentally new kinds of applications.

Don't forget you can also use the waste heat from a device (like a computer) to run a mechanical heat engine to generate power to help run the device. But only partially. I guess we don't do that much because it's probably not economically feasible. That's kind of what turbochargers in cars do though.

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