Can I request for Linus to make a weird project?

[WereCat]

2 minutes ago, DocSwag said:

That's just making a pc to heat something up.

 

Changing it into using that waste heat to generate some electricity that can, say, power case lighting or charge a phone or something would actually be interesting, imo. I might actually consider doing that. Because why not.

Heat rises up.

Place small turbine above the case and let the warm air spin it.

Use the turbine to convert the spin energy into charging a battery.

Use the battery.

[Unimportant]

4 minutes ago, kidlat020 said:

and a LED bulb requires really low power.

 

 

 

 

pump the heat from the cpu and gpu to the radiator and work from there?

If you're happy with a single LED, perhaps...

A pump, water, leads and a radiator themselves dissipate heat, there'd hardly be anything left for the peltier, these things don't work with a few degrees delta. Also, the common PC is not watercooled, adding a pump which uses much more energy then you'd ever could hope to produce is counterproductive.

[DocSwag]

1 minute ago, WereCat said:

Heat rises up.

Place small turbine above the case and let the warm air spin it.

Use the turbine to convert the spin energy into charging a battery.

Use the battery.

The amount of convection that results from the heat a pc produces probably isn't enough to get much electricity out of a turbine, hence why I'm thinking more towards TEGs

[kidlat020]

I agree that the turbine method would be a no here. there's not enough heat, maybe unless you're running a mining cpu/gpu running at 100% load always. but that's for another time.

[WereCat]

3 minutes ago, DocSwag said:

The amount of convection that results from the heat a pc produces probably isn't enough to get much electricity out of a turbine, hence why I'm thinking more towards TEGs

It definitely will be a small amount but you can also use it in the PC case to work as a heat powered exhaust fan.

[DocSwag]

2 minutes ago, Unimportant said:

If you're happy with a single LED, perhaps...

A pump, water, leads and a radiator themselves dissipate heat, there'd hardly be anything left for the peltier, these things don't work with a few degrees delta.

ambient to heat from a rad probably is at least 20-30C delta, I'd imagine.

[Unimportant]

2 minutes ago, DocSwag said:

ambient to heat from a rad probably is at least 20-30C delta, I'd imagine.

Still negligible, these are not the wonder devices you seem to think they are, otherwise the entire world would already use them on anything that gets hot.

My main point stil stands: from wikipedia: Low thermal conductivity: Because a very high thermal conductivity is required to transport thermal energy away from a heat source such as a digital microprocessor, the low thermal conductivity of thermoelectric generators makes them unsuitable to recover the heat.

 

The peltier will extract heat from the CPU much too slow to keep it cool - putting them in series does not help, the opposite in fact. Adding extra heatsinks and whatnot is not an option - you want the heat to go to the peltier, even ignoring the fact you cannot put a peltier AND a heatsink on a single CPU.

[kidlat020]

12 minutes ago, Unimportant said:

Low thermal conductivity: Because a very high thermal conductivity is required to transport thermal energy away from a heat source such as a digital microprocessor, the low thermal conductivity of thermoelectric generators makes them unsuitable to recover the heat.

soooo, what's needed after the heat is removed from cpu/gpu is to store heat?

[Unimportant]

8 minutes ago, kidlat020 said:

soooo, what's needed after the heat is removed from cpu/gpu is to store heat?

Yes, no small feat tough. Storing heat in a usable form is hard. The second thing you'd need is a way to concentrate the heat to make it more usefull in existing conversion techniques. Ideally, you'd want a way to have your 50°C or so CPU heat up your storage device to much higher temperatures, which is also hard since temperature wants to equalise by nature.

[kidlat020]

1 minute ago, Unimportant said:

Storing heat is hard.

Not really.

 

I think of those pizza deliveries where, after driving for half an hour, the pizza is as though it just came out of the oven. and there's no oven in the motorbike. sure, some heat has escaped but this is half an hour, sometimes even on traffic.

[DocSwag]

23 minutes ago, Unimportant said:

Still negligible, these are not the wonder devices you seem to think they are, otherwise the entire world would already use them on anything that gets hot.

My main point stil stands: from wikipedia: Low thermal conductivity: Because a very high thermal conductivity is required to transport thermal energy away from a heat source such as a digital microprocessor, the low thermal conductivity of thermoelectric generators makes them unsuitable to recover the heat.

 

The peltier will extract heat from the CPU much too slow to keep it cool - putting them in series does not help, the opposite in fact. Adding extra heatsinks and whatnot is not an option - you want the heat to go to the peltier, even ignoring the fact you cannot put a peltier AND a heatsink on a single CPU.

Interesting... so basically what you're saying is the TEG won't be able to get the heat quick enough before the heat basically transfers over to the cold side making electricity generated super duper low?

 

And this is why we need better TEGs . Too bad we're fighting physics to do that...

[Unimportant]

1 minute ago, kidlat020 said:

Not really.

 

I think of those pizza deliveries where, after driving for half an hour, the pizza is as though it just came out of the oven. and there's no oven in the motorbike. sure, some heat has escaped but this is half an hour, sometimes even on traffic.

You do realise those courier's pizza bags are heated, right ?

[kidlat020]

1 minute ago, Unimportant said:

You do realise those courier's pizza bags are heated, right ?

even if it is, the point is about storing heat and not losing much while on the road.

[Unimportant]

15 minutes ago, DocSwag said:

Interesting... so basically what you're saying is the TEG won't be able to get the heat quick enough before the heat basically transfers over to the cold side making electricity generated super duper low?

 

And this is why we need better TEGs . Too bad we're fighting physics to do that...

You seem to be confused, stating "cold side" constantly.

A peltier can be used in 2 ways:

• As a heat pump when you apply power to it (a lot). The peltier will then pump heat from one side to the other side (this is where the terms hot and cold side come in). The hot side will get extra hot as it will now contain the pumped heat from the cold side and the power applied to produce the pump action. But the cold side can get colder then ambient. This is not the usage we're interested in, it uses power, not produce it.
• As a electricity generator, converting heat to electrical energy. In this mode the peltier is a poor thermal conductor, heat will only very slowly pass trough it by natural convection, there is no way to force it to go any faster then it does naturally. As such, the produced amount of electricity is tiny. (and your CPU will cook)

[Unimportant]

7 minutes ago, kidlat020 said:

even if it is, the point is about storing heat and not losing much while on the road.

My point is a lot of heat IS lost, that's why they add a heater to the bag.

 

In any case, the thing that seems to be overlooked is that any system you might come up with to solve these problems is likely to use energy itself, most often more then could ever be hoped to produce, that's why no such solutions are commercially available.

[Unimportant]

4 minutes ago, huilun02 said:

There is science behind nuclear fusion

That one's easy, just a 10 minute clip of the sun

[DocSwag]

59 minutes ago, Unimportant said:

You seem to be confused, stating "cold side" constantly.

A peltier can be used in 2 ways:

• As a heat pump when you apply power to it (a lot). The peltier will then pump heat from one side to the other side (this is where the terms hot and cold side come in). The hot side will get extra hot as it will now contain the pumped heat from the cold side and the power applied to produce the pump action. But the cold side can get colder then ambient. This is not the usage we're interested in, it uses power, not produce it.
• As a electricity generator, converting heat to electrical energy. In this mode the peltier is a poor thermal conductor, heat will only very slowly pass trough it by natural convection, there is no way to force it to go any faster then it does naturally. As such, the produced amount of electricity is tiny. (and your CPU will cook)

By cold side I'm referring to if you use the TEG to generate electricity and are looking at the side that's going to be cooler than the other.

[ostrops]

I'm all for it.

[You_are_a_cunt]

I'll say no.

TEG is a nice principle but it's highly inefficient (typical efficiency is 5-8%) and a combined heat output of a PC wouldn't be enough to do much. And you still need to prevent the components from overheating. No, moving heat from one spot to another does not solve the problem.

A watercooling loop is essentially a way of moving the heat from a CPU (or GPU) to a radiator and you're moving the heat from the radiator into the ambient. There's no way going around the law of conservation (or, in this case, capitalizing on the heat generated by the components and keeping them from overheating at the same time)

[Pixel5]

On 26.8.2017 at 8:58 PM, kidlat020 said:

I agree that the turbine method would be a no here. there's not enough heat, maybe unless you're running a mining cpu/gpu running at 100% load always. but that's for another time.

didn't you just say that LED´s don't use much energy so that wouldn't be a problem when someone said the peltier element wouldn't be enough.

 

Same applies to all the solutions you may want, this whole idea will simply not work because you cant get the right conditions to convert the heat back into electricity without having very bad conditions for the PC components itself.

 

there simply is no magic heat to electricity conversion, the other way is easy but sadly can not easily be reversed.