Generating electricity out of the cold darkness of the night sky.

[32 volt boater]

As described in a paper published on Thursday in the journal Joule, the device is based off of a thermoelectric generator that creates electricity from the difference in temperature between a "hot side" and a "cold side." The researchers—UCLA scientist Aaswath Raman, and Stanford scientists Wei Li and Shanhui Fan—decided to take this idea one step further and use the ambient environment of Earth as a heat source and the cold of outer space as one gigantic cold sink.

This $30 Device Turns the Cold of Outer Space Into Renewable Energy

“It literally is generating visible light out of the darkness of the sky. This is not even paraphrasing, this is exactly what it is."

www.vice.com

Wanted this in General discussion, oh well.

 

[sunshine_eggo]

“The big caveat with this work that I’d like to state upfront…is that the amount of power we’re generating is very small,” Raman said.

How small?

Generating Light from Darkness

Night-time power generation analogous to photovoltaics would be an enabling capability for applications such as lighting and wireless sensors. We demonstrate a low-cost power generation device based on thermoelectric generators where the cold side radiates heat to the cold of space by facing the...

www.cell.com

0.025W/m^2

The typical modern solar panel produces about 8,000X this amount of power.

 

[robby]

You could generate a lot more energy just by strapping a Peltier module to your wrist on a cold day
Dave Jones did an extensive video on that paper on his channel

 

[sunshine_eggo]

 

[32 volt boater]

“The big caveat with this work that I’d like to state upfront…is that the amount of power we’re generating is very small,” Raman said.

How small?

Generating Light from Darkness

Night-time power generation analogous to photovoltaics would be an enabling capability for applications such as lighting and wireless sensors. We demonstrate a low-cost power generation device based on thermoelectric generators where the cold side radiates heat to the cold of space by facing the...

www.cell.com

0.025W/m^2

The typical modern solar panel produces about 8,000X this amount of power.

The first solar panel was invented by Charles Fritts in 1883 where he coated a thin layer of selenium with an extremely thin layer of gold. The resulting cells had a conversion electrical efficiency of only about 1%. This invention led to the launching of a movement for producing solar energy.

 

[robby]

“The big caveat with this work that I’d like to state upfront…is that the amount of power we’re generating is very small,” Raman said.

How small?

Generating Light from Darkness

Night-time power generation analogous to photovoltaics would be an enabling capability for applications such as lighting and wireless sensors. We demonstrate a low-cost power generation device based on thermoelectric generators where the cold side radiates heat to the cold of space by facing the...

www.cell.com

0.025W/m^2

The typical modern solar panel produces about 8,000X this amount of power.

Tell you a funny joke.
The first Installer who came by my house to get the Job of putting the Panels on the roof told me that after his last installation the home owner was so impressed by his work because they were able to generate Power at night using the light from the moon.

After that I got all glossy eyed and just nodded as he talked. My only thought was how to politely tell this guy his services were not needed.

I finally found the right company and even though the only thing I needed a professional for was getting the panels up on a two story high Spanish tile roof I still ended up supervising every aspect of that installation.
BTW DJI drones are priceless for situations like this.

 

[sunshine_eggo]

The first solar panel was invented by Charles Fritts in 1883 where he coated a thin layer of selenium with an extremely thin layer of gold. The resulting cells had a conversion electrical efficiency of only about 1%. This invention led to the launching of a movement for producing solar energy.

139 years later we're up to 20-21% from a technology with a lot of potential. TEG technology was discovered even earlier, and it's able to yield... 0.00025% efficient compared to solar.

A rudimentary understanding of thermodynamics tells one that there's no potential energy available. Even if the TEG was 100% efficient, there's negligible energy available in a 2°C temperature differential.

This is nothing but hype that will never amount to anything useful.

 

[MattiFin]

A rudimentary understanding of thermodynamics tells one that there's no potential energy available. Even if the TEG was 100% efficient, there's negligible energy available in a 2°C temperature differential.

This is nothing but hype that will never amount to anything useful.

There is quite a bit more potential than the piss-poor results of this "experiment"
Idea is barely any new and implementation looks...awfull. At least there is potential for "just poor" results

IIRC radiation loss to outer space in clear-sky conditions and dry weather is closer to 100W/m2
Making that to usable energy would need something similar to vacuum insulated solar collectors but in this case optimized for long wavelenght infrared radiation. And desert location.

 

[MrThisIsME]

As described in a paper published on Thursday in the journal Joule,

Thursday 4 years ago?

 

[Ozark Tinkering]

Thursday 4 years ago?

3

 

[pollenface]

I've played with thermoelectric generators, and for the money I spent/wasted, I could have bought a couple more batteries and been better off.

 

[32 volt boater]

139 years later we're up to 20-21% from a technology with a lot of potential. TEG technology was discovered even earlier, and it's able to yield... 0.00025% efficient compared to solar.

A rudimentary understanding of thermodynamics tells one that there's no potential energy available. Even if the TEG was 100% efficient, there's negligible energy available in a 2°C temperature differential.

This is nothing but hype that will never amount to anything useful.

It works




A wood stove fan works by using a Peltier device to generate electricity that powers the motor to drive the fan blades. The heat from a wood stove is conducted through the bottom half of a wood stove fan and the temperature difference compared to the top half creates an electrical current.




I think it has potential. Just need to find a good heat source.

Like geothermal.

 

[efficientPV]

I find that a really odd design. The fan motor is placed in the hottest location and airflow is cooling the stem which should be kept the hottest. The fan motor should be placed up in the heat sink where all the air circulation would cool the heat sink the most. Art over function.

 

[curiouscarbon]

“The big caveat with this work that I’d like to state upfront…is that the amount of power we’re generating is very small,” Raman said.

How small?

Generating Light from Darkness

Night-time power generation analogous to photovoltaics would be an enabling capability for applications such as lighting and wireless sensors. We demonstrate a low-cost power generation device based on thermoelectric generators where the cold side radiates heat to the cold of space by facing the...

www.cell.com

0.025W/m^2

The typical modern solar panel produces about 8,000X this amount of power.

now i am super curious about the cost per watt comparison, but it's quite apparent that the watt per meter squared is very low.

if the panels could become absorbing instead of emissive, heat could be accumulated in a tank with relatively low power? that could boost the delta temperature perhaps? would of course need a little auxiliary photovoltaic for pump.

 

[AJCrow]

I was researching how to make off grid electricity in winter time when it gets to freezing temperatures and I get average 1 hour sunshine per day. I discovered TEG and there is potential. If I understand correctly the key thing here is to get enough temperature variants to each side of the peltier module yes? Well if I need to heat my house or cabin with wood stove there's the heat source AND if it's freezing temperatures outside there's the cold source, right? So if I build closed liquid loop for each source which will provide needed temperature variants for the peltier elements I get electricity out.. perhaps to charge my LiFePo batteries, no?

 

[Old_Skewler]

So if I build closed liquid loop for each source which will provide needed temperature variants for the peltier elements I get electricity out.. perhaps to charge my LiFePo batteries, no?

could you build a peltier effect system big enough to generate the required current to keep batteries charged?

Or how big of a system would you have to build to give you the current?

 

[AJCrow]

could you build a peltier effect system big enough to generate the required current to keep batteries charged?

Or how big of a system would you have to build to give you the current?

I was thinking more like 100-200w output. Not sure how big this system would be. Maybe 50-100 peltier elements which are 40x40mm in size? I'm baffled that there are no youtube videos trying this? In Canada and Northen Europe there are several situations where you have a house or a cabin with solar panels, then winter comes, you get no sun, it's freezing temperatures and you heat your cabin with wood stove. Extreme heat inside the cabin and extreme cold outside the cabin. Perfect conditions to build something like this.

 

[octal_ip]

I was thinking more like 100-200w output. Not sure how big this system would be. Maybe 50-100 peltier elements which are 40x40mm in size? I'm baffled that there are no youtube videos trying this? In Canada and Northen Europe there are several situations where you have a house or a cabin with solar panels, then winter comes, you get no sun, it's freezing temperatures and you heat your cabin with wood stove. Extreme heat inside the cabin and extreme cold outside the cabin. Perfect conditions to build something like this.

That temperature difference will decrease very quickly as your peltier pumps the heat out of the building. You'd find yourself burning much larger amounts of fuel to keep the building warm, fighting an uphill battle against the relentlessly inefficient peltier stripping whatever heat comes near it.
Given the cost of the TEG modules themselves and the additiional fuel you'd need to burn, I think you'd be far better off with just a normal generator.

 

[AJCrow]

That temperature difference will decrease very quickly as your peltier pumps the heat out of the building. You'd find yourself burning much larger amounts of fuel to keep the building warm, fighting an uphill battle against the relentlessly inefficient peltier stripping whatever heat comes near it.
Given the cost of the TEG modules themselves and the additiional fuel you'd need to burn, I think you'd be far better off with just a normal generator.

Yeah, this is my thought as well. But I would like to see someone try to perfect this. It's logical conclusion that whatever heat I turn into electricity I lose that heat and need to burn more fuel. But somehow my brain says that by using peltier elements I can utilize the cold outside as well and it would be net positive outcome. And this is a situation where it's freezing temperatures outside and there's nothing you can do about it, you need to burn fuel to heat your cabin and there's nothing you can do about it AND you need to charge your batteries somehow since you are using electricity in your cabin. So could this be more efficient than basic generator? At least it would be less noise.

 

[octal_ip]

Yeah, this is my thought as well. But I would like to see someone try to perfect this. It's logical conclusion that whatever heat I turn into electricity I lose that heat and need to burn more fuel. But somehow my brain says that by using peltier elements I can utilize the cold outside as well and it would be net positive outcome. And this is a situation where it's freezing temperatures outside and there's nothing you can do about it, you need to burn fuel to heat your cabin and there's nothing you can do about it AND you need to charge your batteries somehow since you are using electricity in your cabin. So could this be more efficient than basic generator? At least it would be less noise.

You'd probably receive a Nobel prize and would revolutionise energy generation across the world if you managed to outperform a normal generator with a solid-state device.
I have a peltier and have experimented with it. They're fun to play with and demonstrate some interesting concepts, but fail to impress when you try to do anything non-trivial with them.
The old steam powered turbine is still king for thermal-to-kinetic-to-electrical energy conversion. Your time might be best spent trying to find a small scale option? At least then the waste steam could still be used to heat your house before condensing back to water. You could even run a closed loop with the low temperatures outside assisting with the condensing step.