this post was submitted on 17 Oct 2023
195 points (94.9% liked)
Technology
59419 readers
4899 users here now
This is a most excellent place for technology news and articles.
Our Rules
- Follow the lemmy.world rules.
- Only tech related content.
- Be excellent to each another!
- Mod approved content bots can post up to 10 articles per day.
- Threads asking for personal tech support may be deleted.
- Politics threads may be removed.
- No memes allowed as posts, OK to post as comments.
- Only approved bots from the list below, to ask if your bot can be added please contact us.
- Check for duplicates before posting, duplicates may be removed
Approved Bots
founded 1 year ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
I was too curious:
Cove's device was a sort of thermocouple, and thus not based on newly-discovered natural processes or scientific principles. In the patent application the device was described as follows: A thermo-electric battery and appurtenances comprising a block of incombustible, non-conductive material, a series of pairs of elements comprising a plurality of elements formed of an alloy of antinomy and zinc, and a plurality of elements connecting said antinomy and zinc elements, said elements connecting said first-mentioned elements being alternatively of copper and of an alloy of nickel, copper and zinc.
https://journals.lib.unb.ca/index.php/MCR/article/view/17744/22231
No such thing as too curious... unless you are a cat. Little dangerous there.
If im reading this correctly, and translated to english:
non conductive block
two different alloys - zinc and opposite to zinc (antinomy) v copper and nickle/copper/zinc.
assuming light hits, produces difference between metal and opposite metal, results in current flow through wire to equalize. Not sure how rare earth Nickle and zinc are, but suppose its not cobalt.
So it’s a Seebeck Effect generator and really isn’t what we’d call a solar device today.
Sorry - above my pay grade knowing what that is. Got a bit of education to get through.
Basically when there’s a temperature difference been two different metals that are touching a small current is produced. You can also go backwards and use electricity to create a temperature difference (Peltier Effect).
They have niche applications because the effect is pretty small. Hardly a realistic substitute for solar panels that use the photovoltaic effect.
Does this mean - in theory - I can put one metal plate out in sun, one in shade, connect with a wire? Or is it a contact surface area thing?
Pretty sure they have to be together like a creme biscuit. You can't put one plate on the equator and one in Antarctica and generate infinite electricity
I mean, it's a DC current so would bleed off over distance anyway.
It could work... but you would need an adequate layer of vanilla creme to compliment the chocolate.
Engineering is delicious.
Well you could, but the resistance in a wire that long would kill it.
Sure that does work but it’s not efficient.
Thermal solar generators do exist but they use a liquid as a heat transport mechanism. These use mirrors to focus the sun into a single point. In general you get more efficiency when there’s a larger temperature difference.
You could also get infinite energy by digging a deep hole since it gets hotter there deeper you dig. It’s just pretty expensive.
Geothermal is the solution we need more of.
This is how fridges work in reverse right? Apply current and make one side really cold?
The device you're thinking of might be a peltier or thermoelectric cooler (TEC). But yes. They're way less efficient than a vapor compression refrigerator, though.
Ohhhh.... Thanks!
Fridges work on gas pressure - compress a gas it heats up, decompress a gas it cools..
Wait.. then what am I thinking of? I'm sure this effect is used somewhere
Looks like you are also a kiwi (that or an AI bot cus i see you everywhere) so probably in an electric chilibin- the reverse effect can be used to cool one plate of metal and heat up the other side.
The whole internet is AI bots bro. You're the only real human here.
If I was a human though, I would be Kiwi. Kia ora!
Yeah, I think that's what I was thinking of.
You are thinking of a thermo-electric cooler (TEC) or peltier cooler. They actually are used on smaller wine fridges but not full sized fridges. They are light-weight, electrically efficient, and reliable. They were also used in the early days of CPU overclocking.
Like the very small fridges that work for a single soda can? Refrigerators use the liquid/gas transition to move heat around. It’s much more efficient.
The only real advantage of Peltiers are simplicity and size.
Nickel and zinc are very common to my knowledge. And much easier to mine than lithium
Oh, it's just a thermopile put out in the sun.
I can see why it never caught on then. You'd be relying on the difference in temperature between the hot side of a thing painted black put in the sun and the cool side in the shade. The amount of energy you'd get from such a setup would be infinitecimal. I'd expect you'd need to do an absurd amount of work and use an absurd amount of material just to power a single house.
The amount of energy it would take to build a "solar cell" thermopile that'd generate 1.5v with a quite high internal resistance would probably be in the megawatt-hours, likely from coal and oil.
There were some numbers in one of the links I posted, hopefully that is able to give some solidity to the theory.
It was early when I read the article, I got the impression that the 9W was for the furnace version of the thermopile electric generator.
The larger versions generated 45, 60 and 240 watts. Another source said 500 watts.
What is the typical conversion efficiency of a solar powered thermocouple?
https://www.resilience.org/stories/2021-10-21/how-to-build-a-low-tech-solar-panel/