Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers

LPF Donation via Stripe | LPF Donation - Other Methods

Links below open in new window

ArcticMyst Security by Avery

Put that waste-heat to use!






Joined
Sep 20, 2013
Messages
17,252
Points
113
I don't see this as useful for laser pointers. It isn't even new technology as we have been able to produce current from PN junctions when heat is applied. If they can get a better efficiency than 19% it could be valuable in areas like large server networks that generate a lot of heat.
 

diachi

0
Joined
Feb 22, 2008
Messages
9,700
Points
113
I don't see this as useful for laser pointers. It isn't even new technology as we have been able to produce current from PN junctions when heat is applied. If they can get a better efficiency than 19% it could be valuable in areas like large server networks that generate a lot of heat.


Yup, it's really not worth it for what's going to amount to no more than a few watts, at most.

Apply it to something like a datacenter that's dumping out megawatts of heat and it becomes a lot more worth while.
 
Joined
Jul 16, 2017
Messages
365
Points
63
I realize it's not much at all...thought it was neat, and they are talking about generating power from smaller, and cooler sources than what was previously possible. Not new technology, but advancing what's already pretty neat.

You guys are right about getting anything useful from our lasers. I was mentioning them in our pointers a bit tongue in cheek...but then again, never say never!! :)
 
Joined
Sep 12, 2007
Messages
9,399
Points
113
The idea is fundamentally flawed, and here's why.

Electronics need to be cooled to prevent over-heating. For low-power devices, stagnant ambient air is sufficient, while high power devices might require chilled water cooling. Thermo-electric generators operate on a heat differential, and inherently pose a thermal resistance across them. All-else-equal, to put them on electronics means your cooling air/water needs to be colder (which requires energy, defeating the purpose of harvesting energy), or your electronics need to be hotter (which is bad for operations and reliability).
 

Benm

0
Joined
Aug 16, 2007
Messages
7,896
Points
113
Indeed, these things would add thermal resistance between diode and heatsinking, which is usually the last thing you want.

The only place i can see it having an application is in things that have huge overkill heatsinking, but in such situation the reason is often just that not much heat is generated to begin with, so there is little power to recover either.

It could be used in buildings where it both improves thermal isolation and recovers energy from the heat gradient. I don't see any application in consumer electronics of any kind for now.
 
Joined
Sep 20, 2013
Messages
17,252
Points
113
From the first law of thermodynamics, a generalization of the conservation of energy, I think if work is done by these devices and they are efficient enough, their work will provide the needed cooling for these devices that need cooling. At least, that is the direction I assumed they are going with this technology.
 
Last edited:
Joined
Sep 20, 2013
Messages
17,252
Points
113
I suspect they will eventually work like a TEC, but won't produce more heat in the process of cooling. I'm sure this technology is no where near ready for that.
 
Joined
Sep 12, 2007
Messages
9,399
Points
113
I suspect they will eventually work like a TEC, but won't produce more heat in the process of cooling.

They themselves don't produce more heat, but if you put a thermo-electric generator between a CPU and a heat sink and try to harvest power from that heat transfer, I promise you (or rather, physics promises you) the CPU will be way hotter as a result.

I use my lasers' waste heat as handwarmers ;)

Put them in your holster instead, and it becomes waist heat :whistle:
 
  • Like
Reactions: GSS
Joined
Sep 20, 2013
Messages
17,252
Points
113
I don't see them working between a device and its heat sink. Rather as part of the heat sink to carry heat away from it. But, they are not anywhere near being able to do that yet. This is my suspicion of where the people working on this are trying to go.
 
Joined
Jul 10, 2015
Messages
9,799
Points
113
Paul, don't you see how the heat harvesting wrap would also produce a restriction in the metal to air heat dissipation rate ? The wrap would turn 15% of the heat into electricity, but it would not pass the other 85% as if it wasn't there, it would reduce the normal metal surface area to air heat transfer causing your device to run hotter, it would be counter productive because the other 85% of the heat energy would be restricted from it's normal transfer into the air.

p.s. I'm not saying the other 85% would be completely blocked, but restricted causing heat buildup in the device at a faster than normal rate.
 
Last edited:
Joined
Sep 20, 2013
Messages
17,252
Points
113
That is why I said in post #2, that once they get the efficiency up way above 19% that this might be a possible way to extract electricity from large server network facilities.
 
Last edited:




Top