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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

#71

Post by grecy »

galangalalgol wrote: post #68
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…

Could you chain 3 of them using a tank of coolant at room temp as the between value. Or make it water and put the TEC on the cold side of the tank

The plan is to have a tank of glycol coolant sitting outside (at around -20C to -40C ambient) and mount a radiator outside. I'll use a fish tank pump or similar to circulate the coolant. Put water cooling blocks onto the TECs so the wood stove heats one side to around 100C to 200C, and the cold coolant coming in brings it back down, to hopefully get a temperature difference in the range of 100C (ish).

It's all just an idea right now, first I have to find TECs that are up to the heat directly touching the stove.

Re: New Material Breaks World Record Turning Heat into Electricity

#72

Post by adw »

correct_horse wrote: post #60
adw wrote: post #37

Earlier quoted context omitted.

I am twenty years removed from it, but I used to be well-informed on this kind of thing; I have a PhD in mineral physics. Let's see how well I can explain this (haven't read the article, yet, sorry! Waiting for a plane...) So you're no doubt familiar with the physics of a vibrating string; it resonates at wavelengths (length of string, 2 * length of string, 3 * length of string... n as n->inf). So you can express any…

I think you meant to say length of string, length of string / 2, length of string / 3, ... https://en.wikipedia.org/wiki/Harmonic

Indeed I did! Thank you. (This is what happens when you write in a hurry.)

Re: New Material Breaks World Record Turning Heat into Electricity

#73

Post by adw »

agumonkey wrote: post #58
adw wrote: post #37

Earlier quoted context omitted.

I am twenty years removed from it, but I used to be well-informed on this kind of thing; I have a PhD in mineral physics. Let's see how well I can explain this (haven't read the article, yet, sorry! Waiting for a plane...) So you're no doubt familiar with the physics of a vibrating string; it resonates at wavelengths (length of string, 2 * length of string, 3 * length of string... n as n->inf). So you can express any…

Well written I must say. Makes me very curious about crystals and material physics (especially since I got interested in low level electronics and semi conductors). Any suggestion to read ?

Not really light reading, but any good solid-state physics textbook would cover most of this. I learned from https://www.amazon.co.uk/Introduction-Mineral-Sciences-Andre..., which is quite a bit more explicitly mineral-sciences focussed.

Re: New Material Breaks World Record Turning Heat into Electricity

#74

Post by esotericn »

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…

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

Re: New Material Breaks World Record Turning Heat into Electricity

#75

Post by arghwhat »

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…

You'd be actively cooling your wood stove by much more than the power you'd extract, and you won't get more than enough to charge a phone or laptop. TECs are just terrible.

You'd get much better result by making a small steam plant with the same setup: boil water on stove, drive plant (turbine or piston), condense outside, repeat.

However, if you really want to do this with TECs, stack them to lower the per-unit temperature differential, or distribute the heat energy over a larger area and run them in parallel.

Re: New Material Breaks World Record Turning Heat into Electricity

#76

Post by mkagenius »

adw wrote: post #72
correct_horse wrote: post #60

Earlier quoted context omitted.

I think you meant to say length of string, length of string / 2, length of string / 3, ... https://en.wikipedia.org/wiki/Harmonic

Indeed I did! Thank you. (This is what happens when you write in a hurry.)

Hope you had a nice flight. Happy new year.

Re: New Material Breaks World Record Turning Heat into Electricity

#77

Post by hooande »

ragerino wrote: post #66
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…

That's a cool idea. I came across this link because I want to build cheap small sensor stations using LoRa to transmit data (gps location?, temp, humidity, air quality) to a central server. Solar is not really an option because it needs to be cleaned once in a while.

how big of a temperature difference do thermoelectric materials usually require? is it like dozens or hundreds of degrees over a given period, or something that's likely to be encountered in a normal environment?

Re: New Material Breaks World Record Turning Heat into Electricity

#80

Post by agumonkey »

adw wrote: post #73
agumonkey wrote: post #58

Earlier quoted context omitted.

Well written I must say. Makes me very curious about crystals and material physics (especially since I got interested in low level electronics and semi conductors). Any suggestion to read ?

Not really light reading, but any good solid-state physics textbook would cover most of this. I learned from https://www.amazon.co.uk/Introduction-Mineral-Sciences-Andre... , which is quite a bit more explicitly mineral-sciences focussed.

Aight, I'll see if I can digest it.
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