Solar Power can now be generated at NIGHT! It's really TRUE!

[@scottwilliams1623]

Interestingly the majority of the solar power technology originates either directly or indirectly from labs in universities in NSW, much of it under the direction of a single professor, Prof Martin Green, literally a genius in this field of solar. In fact the largest panel producer in China was founded by one of his PhD students who was coaxed home by his government in China to set up what has become the largest solar industry in the world.

[@jimparr01Utube]

Thanks for cool info and history Sir.

[@jb76489]

@@scottwilliams1623 citation needed

[@firstnamelastname9918]

And if I understand the dynamics correctly, China is subsidizing these industries like no other countries are, so they end up with an unfair economic advantage. Yeesh, what a mess we're in. But when it comes down to it, I'm probably going to buy my panels from them. EDIT: Oh, and thank you for posting this too!

[@raifikarj6698]

Damn what a prophecy, name really was carry meaning to the child. How come the person furthering green energy is also have green in his name.

[@jb76489]

@@scottwilliams1623 citation needed

[@karlstathakis7786]

As my thermodynamics professor always told us: the climate crisis won’t be solved by a silver bullet, but by silver buckshot.

[@waylonk2453]

Grin! That's a great analogy.

[@peterd9698]

Climate change not a werewolf.. gotcha.

[@nustada]

As a professor of bullshit, the climate crisis will be solved by acknowledging its not a crisis.

[@jb76489]

A more honest thing to say would have been “the climate crisis won’t be solved” It’s already far too late

[@Leonhart_93]

@@jb76489 Yeah well, more signs point to it being blown out of proportion. Simply because they don't have the data to support those claims.

[@patrickcorcoran4828]

I used to work in an off-grid office for a solar installer back in the early 2000s. The ironically named MidNite charge controller often showed production on days with bright moonlight. For grid-tied systems the moonlight was never bright enough to turn on the inverter.

[@pjeaton58]

Now for a nice big mirror on the Moon !

[@jasonkeith2832]

​@pjeaton58 The moon already is a big mirror, especially considering that it's one of the only stellar objects bright enough to be seen during the day purely through reflective illumination.

[@BrinJay-s4v]

Exactly we have all burned paper with a a lens and sunlight, never works with moon beams. No photon can be more energy / hotter than its emitting surface and energy is always on its gradient high to low , hot to colder.

[@TinCanToNA]

4% albedo go brrrrrrrt

[@jack504]

Saying it could power your wifi router is generous. Lower power routers use around 5W. If they can improve the efficiency of these thermoradiative diodes tenfold to 18% (similar to good PV) instead of 1.8% and you had 20m2 of these on you roof you would get 0.45W of power, a tenfold shortfall on power demand of the router. I'm all for multiple solutions but this is really a distraction which in reality will have very low power niche applications if any.

[@Beregorn88]

the theoretical limit of this thing is 0.125 W/m^2; commercially available peltiers can do 22W/m^2 on the same dT...

[@1155727]

@@Beregorn88 should that not be watts instead of milliwatts in "0.125mW/m^2"? Not that it really makes a material difference in this case...

[@thedamnone]

The first question should be: can it even power the inverter?

[@predabot__6778]

In this application, probably - but within thermally intense INDUSTRIAL processes? I see potential there - within various power plants for instance, where a lot of energy is lost in the various steps - usually in the form of Infrared Radiation. If the technology can be improved to at least a 10+% efficiency, I can see some future for it, harvesting various waste-heat.

[@Beregorn88]

@@predabot__6778 the problem is that even at 100% efficiency, this process is orders of magnitude worse than other already available technologies, and this is before you factor in the extremely high cost of the materials used: in the most ideal case, the best this thing can do is 0.125 W PER SQUARE METER, while commercially available, off the shelf peltiers can do, RIGHT NOW, 22W/m^2...

[@markofdistinction6094]

I was a scientist/engineer working with HgCdTe infrared detectors for night vision sensor for over 31 years. HgCdTe diodes are outrageously expensive. (some of the state of the art sensors the size of a postage stamp can cost tens of thousands of dollars). There is so little energy to be harvested per square inch that even if the cost can be brought down to that of modern "traditional" solar cells, the cost to harvest infrared energy seems impractical.

[@nonotorious1467]

It's the same thing in 99% of these types of videos.

[@manoo422]

It doesnt take a genius to work out there is VERY little energy around at night unless you are in the middle of a desert.

[@thedave7760]

Shh , we don't need your sciency engineery type of thinking around here this whole universe of "renewable" energy relies on unicorn farts, fear and unwarranted hope

[@phizc]

​@@manoo422 deserts tend to be quite cold at night. The average night time temperature in the Sahara Desert is -4°C or 25°F.

[@manoo422]

@@phizc Yes that was the point, deserts give up huge amounts of energy every 24hrs, going from 40C+ during the day to -4C at night.

[@ElkoJohn]

Thanks! from Reno, Nevada USA

[@JustHaveaThink]

Thanks for your support. Much appreciated :-)

[@zatar123]

Any techno trick that can turn ambient heat into usable energy is definitely worth looking into. So far, this is just one more idea than looks good in the lab but has yet to prove itself out in the real world. Even so, I'm always excited to hear about stuff like this because, someday one, or more of these clever ideas is going to make it out of the lab and prove itself highly useful

[@hugegamer5988]

It’s been proven in service to have up to 10% of the energy density of traditional solar. Experiments go back maybe 50 years on this, It’s just a simple thermal gradient supplying the power, the cold of space in the night sky on one side and the relatively warm earth on the other.

[@robertunderwood1011]

One can always look for the jewel in the junk pile….. But how much time do we have?

[@orkin2525]

So many breakthroughs can do everything but leave the lab.

[@BrinJay-s4v]

Only useful if its cost effective and usually it is not like converting wind to generation costs exceeds the benefits.

[@orkin2525]

@BrinJay-s4v it's similar to hydro. There are places where it works, and many more places where it doesn't.

[@Neilhuny]

As a poor supermarket worker I'd like to add my thanks to all the Patreons that support this channel! Dave Borlace is frigging brilliant - well researched, knowledgeable and a great communicator, we all benefit from these videos. Now I need to persuade my flat-earther believing colleagues that cathedral spires have never taken power from the sky ....

[@darkskye5561]

You misinformed, sends power to our alien overlord in the Skye 😅😂😂

[@3nertia]

@@darkskye5561 How do I contact them for a ride of this planet? 😅

[@zombi3lif3]

Call you bozo? Never! You are awesome, Dave!

[@damienflinter4585]

Yep, master communicator of complexity to real bozos like me. I even caught the gist....which beats catching cold.

[@davidwilkie9551]

Didn't specify what type of...

[@6Sparx9]

@@zombi3lif3 "never turn down the offer to call someone a bozo" -Francis Bacon, probably

[@timeenoughforart]

Perhaps we need thermo radiative clown noses to power our phones....and assorted politicians.

[@alangilbert6544]

Thank you as always Dave - doing all that research and giving it to us in simple language.

[@GoofieNewfie69]

Back in 2012, we had a guy from MIT come in to do a presentation on solar, his company was researching materials to make full spectrum solar panels. They could detect and measure infra red and close spectrums but couldn't transform it into an economical usable energy. At that time it cost four times that of nuclear. Looks like the cost is coming down.

[@RichWoods23]

"How the bloody hell do they do that then?" An important question, one which isn't asked nearly enough.

[@twoina]

If you could improve the efficiency by a factor of 20 - which is very optimistic - we are at 50mW/m². Let your watch have 10cm² of area for collecting, it would be 50μW in an ideal (!) situation. But only in the winter, you don't have the temperature difference in the summer. An Apple watch needs about 50000μW on average! An simple Apple watch battery can provide 50μW for 3 years with one charge.

[@phizc]

Also, it would need to be able to radiate the IR, so it would need to be on the top of the smart watch, and you couldn't wear any clothes over it..

[@b3tondu]

@@phizc If the system could be installed in the strap not the watch, then it could make sense. The benefit would be that during training when the watch is usually working harder, the body is also enabling it to get more energy. I know it's a long shot, but I did some math just for fun. Average smartwatch has a 500mAH battery, so this is roughly 1g of Lithium (if I understand correctly). According to demandsage nearly 180 million smartwatches are predicted to be shipped in 2024. So if we could replace the batteries in all of them with this tech, it would mean 180 tonnes of lithium per year. Which would be around 0.1% of the total Lithium production.

[@phizc]

@@b3tondu according to a FedEx document (and backed up by ChatGPT 😅), a rechargeable lithium ion battery has 0.3 grams per ampere hour, so it'd only be 0.15g for a 500mAh battery. But that's the least of the problems. If it didn't have a battery at all, it would lose power any time the conditions weren't right, or it needed some extra power for to vibrate and play a notification sound, and that's if it could even produce enough power for baseline functions (it's not, by a factor of a few hundred). It would also stop working when you put on a jacket. Etc. Etc. Etc. Interesting idea, but wildly impractical.

[@sami.ehlers]

Thanks, Dave! I love hearing new ways to tap into the available energy that surrounds us.

[@electricalychalanged4911]

The problem is the temperature difference required here. 12,5 C is a lot. Your wrist wach will never achieve that neither your smartphone in most circumstances. Space application might be different as there are much higher temperature differencees achivable here though as others pointed out peltiers are right now way more efficient than this diode.

[@robwoodcock8566]

Another great insight - I worked with a company that replaced pub cellar cooling with air source heat pumps/ no silver bullet but a very useful removal of about 25000 kWh of energy per pub ! Shame it peaked too early as a business. Must contact the Heatgeek!

[@jonm7272]

25,000 kWh? Really? Over what timescale was that huge amount of energy recovered?

[@robwoodcock8566]

@@jonm7272 annually, remove the hot water boiler, line coolers working more efficiently , older cellar cooling replaced .

[@robwoodcock8566]

Pubs use huge amounts of energy - bills £50,000 year were common. Very old heating and cooling systems from years of lack of investment .

[@statsmad2812]

Interesting technology and something to look forward for potential commercial applications in a few years' time. The small device powering option seems the more plausible candidate.

[@dertythegrower]

LED are also becoming more efficient... what if sun solar power made enough energy to make using LED on the solar panels a win in production at night... its close already

[@balasubr2252]

The future of energy from photonics is indeed promising 🎉

[@firstnamelastname9918]

@@dertythegrower wait, wha? Are you being silly or serious? If the later, it's not possible -- violates the laws of thermodynamics.

[@alilonghair7792]

So, in the future, we'll be charging our phones from our hot cup of coffee! Cool! 😎

[@jonbeecroft1102]

You are quite right to cover this Dave! Perfect for low power IoT, although your eye candy cover picture is a little misleading 😂

[@_yonas]

Is it? How much energy is required to produce, ship and sell these cells and all the incredibly low-power microelectronics to make them work? These cells may never recover their initial energy cost.

[@michaelbuckers]

It's a worse version of peltier devices. How is this at all good? As for low power devices, a 36CR battery will be able to provide more power and for longer period of time than this thing.

[@jameshughes6078]

@@michaelbuckers A *dead* 36CR battery will provide more power for longer than this

[@1155727]

Perfect? Hardly. A more fitting adjective would be "horrible". There are lots of better options.

[@pawelhyzopski6456]

Iot is better in fission energy. Small battery can power it for decades.

[@patsommer4495]

As someone who painted floor black with a large south facing window, turning heat to energy sounds better than installing AC.

[@firstnamelastname9918]

Whoops. Almost sounds like something I might do!

[@serge8400]

I should try that with a north facing window…in New Zealand.😂

[@1155727]

Ok, let's get this straight - from (7:24) in the video, they got 2.26 mW / m^2 at 1.8% efficiency. So even if we are generously allowing an eventual increase of efficiency to 100% (obviously never going to happen), we would generate 126 mW / m^2. But even that is so ridiculously little that you have to wonder whether this technology will ever recover the energy needed to manufacture a module during the lifetime of the module... There may be fringe applications somewhere, but even that does not look promising.

[@demoniack81]

Not to mention that if they DO manage to get the efficiency up to the point where they're radiating hundreds of W per panel at a decent effieciency, then your panel is just going to get cold and start radiating way less, or get covered in frost and stop working at all because the ice is blocking your IR emission. Heat doesn't just manifest destiny itself into these things, it has to come from somewhere. The only application (other than niche space related stuff) where I could imagine them having any potential (provided they get AT LEAST a 5 orders of magnitude increase in power density) is extracting a small amount of extra energy from the coolant stream of existing thermal power plants. Or possibily from the AC condensers of large commercial buildings. Things that already need to actively reject hundreds of kW of heat.

[@dmazeau]

Most people think that a trip to the Sun would be very dangerous, but I have always thought the trip would be much safer if they just went at night. 🙂

[@matildamcgillicuddy3935]

LOL

[@Rob-e8w]

Suggest that idea to Mr Musk, he'll probably throw a few million dollars at it.

[@lorenzzorzt]

@@Rob-e8w He wouldn't

[@FarmerRiddick]

This comic put a smile on my face. Thx! 🙂

[@aquelpibe]

Get there by the break of dawn and rush back home before the sun actually comes out. Sounds doable.

[@MrJamesatWork]

Congratulations! You've managed to make someone who's allergic to good news honestly excited. Thank you!

[@1155727]

What good news? Did I miss something? Sorry, I am an electrical engineer and did the numbers on the thing... If you are looking for good news please keep looking.

[@brianmckeever5280]

"Form an orderly queue." So funny. Interesting idea!

[@revblade]

Is this the queue where we all call him a bozo?

[@michaeljamisontigers]

I build a machine that follows the sun with 10 x 650w panels , I have not bought any electricity for a whole year , totally off grit and charge my car , the trick is to get the last sun rays and the very first ones then You can do it with ease , I am in South Africa .

[@rglservices7944]

Ok sir, so let someone learn from you how to build A machine to follow the sunlight

[@daphnescombine]

Thank you, Dave. The application for wearables is exciting. Yet another potential challenge and opportunity to harness energy that is currently being ‘wasted’. I always enjoy your videos. Always positive and very easy for the layperson to understand.

[@NobbsAndVagene]

You're so positive and polite. Watching your videos makes me feel like I am in the presence of a great zen master.

[@OyvindSOyvindS]

Best channel on the entire Internet

[@lauriescott8364]

Always appreciate your research! Keep up the good work!

[@martincotterill823]

Great video, Dave, we'll have this tech before fusion is available for sure

[@JeffBilkins]

Generating power from waste heat seems fun, could also be great at cooling spacecraft.

[@waylonk2453]

Ah, now there's an idea

[@marsupialdungbucket]

That's an interesting thought - the heat differentials between the inside and outside and the dark and light sides are huge.

[@NoHandleToSpeakOf]

Cooling requires heat rejection to be at a certain rate. That rate is low if you are using heat to generate energy.

[@phillipsusi1791]

The Voyager spacecraft operate on this very principal. They have a radioisotope that generates heat, and use a thermocouple to capture some of that heat energy escaping into the void of space to generate electricity. When you have a tiny space probe billions of miles from Earth where that is all you can do, then that's what you do, but that doesn't really help us billions of humans living back here on Earth to power all of the things that we do. Some radioisotope and a 10 or 20 square meter radiator array that can generate 50 watts of power just isn't going to meet the energy needs of my house. Not by a LONG shot. And when such a system that only generates 50 watts of power costs about a million bucks, why are we wasting our time even talking about it? I'd much rather talk about a solar system that costs $20,000 and can run my whole house than a similarly priced project that could barely run my cell phone.

[@massimocole9689]

If your goal is cooling a spacecraft putting as few steps between the heat source and the radiator is the best thing to do. Anything that generates power from the heat flow reduces its temperature, which makes the radiators work way worse and need to be more massive. Radiation increases with temperature to the forth power. Make the waste heat 2 times cooler to extract a bit of electricity from it, and you need 16 times more radiators to get rid of it.

[@PeroniPete]

A battery storage breakthrough will turn everything on its head, Dave. Keep up the great work, what you do is fantastic.!

[@PMA65537]

turn everything on its head - it is New South Wales

[@WilliamCarnell-k9g]

Unfortunately batteries have a limited life whether it be 20 minutes for a non-rechargeable dry cell to a couple of decades for rechargeable at which time entropy has taken its inevitable toll and the battery fails. No problem, build a new one, unfortunately (again) that costs money and it's economically prohibitive. It's cheaper to build a gas-fired power station and keep it on standby than storage batteries, unless your breakthrough is the repeal of physical laws.

[@michaelbuckers]

There won't be battery storage breakthroughs. We're already maxing out physical limits of batteries, as in there aren't even any theoretical places to get gains from. Maybe fuel cells will fare better, but a fuel cell is basically a solid state internal combustion generator, so not the same thing.

[@johnwale2886]

@@WilliamCarnell-k9g A gas-fired power station has a lifetime of up to 40 years, whereas a pumped hydro storage system has an operational lifetime of about 50 years. Vanadium flow battery systems can last for about 25 years. There are long-term storage solutions already available, but they typically have low energy density. In some places this matters, but in others it may not. It might well be cheaper to build the power station initially, but what's the cost of operation over its lifetime? At least with energy storage systems you don't have to keep putting fossil fuel into them and you don't therefore have to deal with so much environmental consequence of that.

[@davidlane1137]

@@johnwale2886 Two things jump out at me here. No mention of nuclear power and its 80 or so year lifespan. Then there is the cost of production in energy of copper. No matter what you use to move electrons in a copper conductor, you still have to mine the copper and make it at a scale never seen before to achieve the electric utopia. Forget storage of chemicals (batteries) forget the age of whatever source you use to move the electrons. Remember you need a very conductive metal for the electrons to move through. That and only that will dictate the success of any device you use to move the electron.

[@agw5425]

You can supply the power you need from passive heat alone by using a heat pump and a stirling generator as follows : from 1 kwh input you can get 4 or more kwh of collected and concentrated heat, this heat drives a stirling generator that is 40% (or more) effective that gives you 1.6 kwh. send 1 kwh back to the heat pump and you will have a 600 wh net gain with no fuel wind or solar, just waste heat we do not want anyway. Scale that up and use optimised components and you will get even higher returns. I have seen (on this channel) heat pumps with 80-90 % efficiency so there should be some engineers that could design/produce what I suggest or even better. I have yet to hear any convincing argument against the numbers/idea, feel free IF you can backup your words with facts of cause.

[@LuaanTi]

The heat pump is the most efficient when the temperature gradient is very low; in contrast, the Stirling engine is more efficient with increasing temperature gradient. Both are two sides of the same coin. For bonus points, both are Carnot engines, so you can literally just say that an ideal heat pump working together with an ideal Stirling engine under ideal conditions will produce... exactly zero net energy. Heat pumps are literally running the same Carnot cycle backwards. Of course, a simple view from laws of thermodynamics makes this rather obvious without going into any details. Of course you can't pump heat there and back again while extracting net energy. Where would that energy be coming from? The only way to make this work would be to have two different heat sinks - one relatively hot, and another relatively cold. Which gets you back to... solar power. It's what we already do! :D Have something that gets heated throughout the day... and use that heat as needed, through day and night. As long as your heat reservoir heats up faster than the ambient environment (whether that's the air, ground or a convenient cold lake nearby :)), you can extract useful energy from that (including even such low-tech solutions as "just use it for heating directly" that are used _everywhere_ in the hotter parts of Europe for hot water, for example). But it still comes from the Sun. Of course, you can use a more passive way - say, ambient air vs. that convenient cold lake. But that lake stays cool by losing water to evaporation and, again, exploiting the difference between the day and night. It's just a heat reservoir, and that added heat changes things. Heat pumps aren't magic, and neither are Stirling engines. We understand both very well, and have understood them for centuries. The first refrigerator was constructed in 1748, and the operation of the heat pump was described in great detail by none other than Lord Kelvin in 1852. Since 1928, Geneva's city hall has been heated with a heat pump that extracts heat from the nearby lake. The thing that tripped you up is that you think of those machines in terms of "A has 80% efficiency, B has 40% efficiency". But efficiency isn't a fixed thing, it depends on other factors - like the temperature gradient in this case. In fact, heat pumps can essentially get unlimited efficiency - a single kW of power in can produce as much kW of heating as you desire... provided the temperature gradient is small enough. But the more efficient the heat pump gets, the less efficient the symmetrical Stirling engine :) And needless to say, the smaller the temperature gradient, the less energy there is to extract and the harder it is to _keep_ the temperature gradient.

[@adus123]

Just imagine how efficient the first solar panels were all them years ago compared to now. The Earth receives and admits a hell of a lot of energy. There must be more ways to capture that energy. We just need to find a way.

[@1155727]

We already have several ways: wind, and daytime solar, just to name two of the most effective ones. Of these two, wind, can still work in the night. The intensity of light (including infrared) during the night is so pathetically low as compared to daylight sunshine that it doesn't look too promising for that... Look at the numbers milliwatts per square meter! Even if they could get efficiency up to 100% it would still be milliwatts... This is not what we need.

[@MikeAG333]

....all (those) years ago.....

[@rachelcarre9468]

I’m looking forward to seeing Pervoskite PV solar panels on homes and remembering that I heard it here first! Thanks Dave, keep up the good work!

[@jaccurtis5789]

Even if these can be made into insanely cheap panels, and they get from the current 2% to near 100% efficiency, I can't see this working for anything other than niche uses for very low levels of power generation. A full size solar panel (around 2m²) would only generate 0.25W at 100% efficiency, which is more than it could reach. If the efficiency can get near regular solar PV at about 20% (still over 10x current efficiency), a full-size 2m² solar panel would get you 0.05W, which might just about run a dim standby LED. Seems that physics says no to this idea being useful on a large scale unfortunately

[@Texacate]

Exactly. The math is the math. Never confuse science with engineering.

[@pawelhyzopski6456]

Same goes for solar panels. More energy used, the better are our lives in general. Solar has a nasty limit. Good tech for some off grid applications or nasa stuff but useless on earth otherwise. I much rather see solar panel on roof of a car to recharge the battery as a backup than try to pull enough to satisfy needs. One has to have enough land to put enough solars to make them usable. High density population areas? Good luck.

[@daniellapain1576]

Did a project after highschool way back around 2009. I was following an instructable on how to build a solar cell from scratch. I managed to synthesize some blueberries in a rudimentary way, to extract a specific chemical from it. I had also used titanium dioxide and graphite. I also managed to get strontium aluminate into the cell. The end result was a solar cell that could store light particles during the day and release them at night. I only managed to get 18v daytime and 2v night time. I couldn't tell you the amps or watts. I would have to rebuild it accept with better materials this time around. Though technically I was just happy to prove a news anchor wrong who joked about solar panels working at night when I seen it on tv. So I figured out a way. Solar cells from scratch is something that isn't easy to do since the hardest part is finding a large enough piece of glass that has a conductive surface. For the time it wasn't easy to source and was expensive back then.

[@jimparr01Utube]

Just guessing, but I suspect this 'breakthrough' is not as efficient as a standard thermocouple device (Seebeck effect). Yup, you would need many thousands of series-wired thermocouple junctions to produce a few useful volts of electricity with small temperature differentials like 10-15 degrees centigrade. However, one major advantage of such a harvesting method, is that the available 'current' is not intrinsically limited by the device itself. High school Science class demo' circa 1966... Two dissimilar-metal bars, each about 200mm long and 25mm square with ends cold-welded together and suspended on tripods at the master's bench. A Bunsen burner going hard out at one end, for about 10 minutes, while the other end was kept cool with dry-ice. An abracadabra flourish as the master closed a knife switch that completed the circuit between each end of the bar. We all jumped at the loud bang, as a ~1kg iron bar instantly lifted about 200mm from the bench-top and 'stuck' to the elevated bar. It remained there for at least a minute after the burner was extinguished.

[@jaganathanjonathon8102]

Wondering if Fresnel lens or multiple convex lenses above a panel with small circular active areas on the panel would produce enough of a temperature difference to produce a useful amount of electricity. Perhaps a PV layer combined with a thermolectric layer combined wit a heat sink. Would love to know.

[@jasonneugebauer5310]

From what I understand most if not all modern grid tie inverters are equipped to receive instructions from the electrical utility company to tell the inverter to perform grid regulation services such as adjusting the phase relationship between current and voltage and also smoothing the wave form. This free power adjusting capability provided to the utility at thousands of end user connections can provide enormous cost savings to the utility and increases power quality and reliability.

[@ItWasSaucerShaped]

the power density is uh YIKES even at much higher efficiencies, the best case scenario for this tech would be, like... emergency LED lighting. which is super niche and it seems far too material intensive and expensive to really accomplish even something like that EDIT: that said, i don't agree that this is a 'distraction'. science is a process of both working out what does work AND what doesn't work. someone has to do the dirty work of crossing technology off of the list of being non-viable, and personally i'm glad someone was both able and willing to build a lab-sized experiment to do just that

[@robertunderwood1011]

Granted . But Dave can’t waste too much time pursuing ideas that he already knows are highly unlikely. Too much of this and the channel loses credibility. There is some credible work to Dave has not given sufficient attention to : That would be the replacement of farming with factories, producing single cell protein, fed by gases, like methane and carbon dioxide…. And hydrogen. And of course, any improvement in the process of fixing nitrogen, would be information to get us all to stand up and cheer .

[@1155727]

Thank you for a very insightful comment. Absolutely agree that the objective of science is to expand and deepen our knowledge and understanding of the world. And this necessarily means that we often end up spending time in areas that turn out to be less productive for practical applications. But being able to quantify these things is often still worthwhile.

[@Tomthumb222]

Don’t put yourself down. Without these videos, the average guy in the street would rarely get to know of advancements. Keep em coming my friend.

[@steverobbins4872]

Seems like you'd get more power from a photovoltaic cell in moonlight than from a thermoradiative cell on a cloudless night.

[@1155727]

That's an equally useful and sobering comparison! Very fair, too.

[@katejackson7432]

awsome vid dude! love it! could've watched another hr on the subject

[@Texacate]

So we're talking 5-6 orders of magnitude less W/m² than today's PV panels? Solar Freaking Roadways baby!!

[@1155727]

Exactly! You are right: even improving the efficiency by a factor of 50 (it will obviously never get that far, because that would be near 100%) is not going to make this look good.

[@Texacate]

Don't tell Dave Jones #eevblog about this video. To suggest that tech is even remotely useful to society is laughable. (Aside from its pure academic value. It does further the list of green energy sources that we should NOT pursue commercially. That has some value, right?)

[@cantbeatpie]

Thanks!

[@JustHaveaThink]

Thanks for your support. Much appreciated :-)

[@Ima-hoot]

2.26 mW per sq m at 1.8% efficiency for 12.5 C differential. 100% efficiency means about 125mW per sq m. The area of a watch is tiny. The human body diff air temp is higher than 12.5C but energy generation will be tiny. More energy generation with hand motion (kinetic energy) than this concept The maths says this is NOT a practical real world solution.

[@marksmit8112]

Using the technique called radiative cooling, which takes advantage of the fact that objects radiate heat to the colder surroundings of space, which can be converted into electricity via thermoelectric generators. Energy can be harvested but its still in development

[@Yanquetino]

If the power would be sufficient to help counter the "vampire" drain in our appliances overnight, it would be a winner!

[@1155727]

No, it wouldn't, because there are more efficient solutions already. The problem with this technology is that it very probably does not even recover the energy needed to manufacture it during its entire lifetime...

[@joecummings1260]

Vampire energy drain for a whole home is like 5 or 10 watts, you are talking about like 2 cents worth of electricity a day

[@patriceblakeway4421]

Good show, nice to have variety and show that basic research can be productive.

[@myphone4590]

Mercury and cadmium. Definitely something you want to deploy everywhere humans live.

[@chesterfinecat7588]

The company will be bankrupt and nowhere to be found long before anybody can prove there was a problem. So sure. deploy away.

[@goobyboxxton8526]

Exactly my thoughts as well. But to be fair there's still a substantial number of homes with lead paint and water pipes, so what's a couple more elements? /sarcasm

[@paulsmallwood8779]

No way am I going to bag out the good folks at UNSW Solar. All power to them!

[@Welgeldiguniekalias]

Pedant here. We most definitely cannot agree that greenhouse gases capturing heat is a bad thing! Without the greenhouse effect, our planet would be a frozen wasteland. The issue with greenhouse gases is we now have too much of a good thing because of two centuries of uncontrolled emissions.

[@crispypancetta681]

Pendant!

[@alexanderdekeuyper2990]

A bit of booze can be good for confidence, to much and you’re a hooligan. The point is where we started (pretty much a sweet spot for greenhouse gases in our atmosphere for Homo sapiens)

[@davidlane1137]

@@crispypancetta681 Okay just for you, a pedant is a book learner. As they say pedantry is its own reward.

[@firstnamelastname9918]

"Frozen wasteland"!? It's not like that's ever happened here before! */s* 😁 (e.g., both snowball Earth periods)

[@kena4977]

Ahh yes, a fellow unrepentant pedant.

[@dprcontracting6299]

Dave, informative as always. And your great sense of humour is right up there too. Thanks again.

[@leftcoaster67]

Solar cells can collect 1% during a clear night during a full moon. It's minimal. But remember it's light it's absorbing, not heat.

[@michaelsmithers4900]

Heat has 3 forms of movement that I’m aware of, convection, conduction, and radiation. Radiation or Electromagnetic radiation is more like light in how it moves. I believe this is what they are capturing.

[@trueriver1950]

Yes, solar panels can get small amounts of power from moonlight, and it's minimal. You're also missing the point: this is energy generation by emitting into a chillier source, not by absorbing anything. That's why this research is not about harvesting moonlight or even starlight. They are exploring the mirror image effect that occurs when the sky looks cooler than the panel. Whether you could get that moon power as well as the cooling power I don't know: but if that is possible one layer of the panel would be absorbing visible photons (in the usual way) and the new layer would be emitting infra red positions. My intuition is that the two processes would interfere, but clearly the hope would be that they can enhance one another.

[@ausnorman8050]

"Moonlight intensity is about million times smaller than sunlight intensity" Moon light = pointless as it doesn't work as you can't get the voltage up enough for the inverter to turn on.

[@monikarathbone3478]

I'm 76 soon to be 77 love your info and don't tink I make it to that day of energy business liberation but I'm hopeful for the world.

[@brucebr1037]

I'm one year behind you. I just hope to make it to lunch each day.

[@lineinthesand663]

This is the thermodynamic equivalent of the Law of Diminishing Returns.

[@firstnamelastname9918]

But it IS also an optimization issue and I'm going to guess that the amount of work done on it is small in comparison to the potential for optimization. If they come up with some combination of doping constituents then it can be a game changer. EDIT: But even at it's current efficiency, it likely has real world implications for select devices, such as satellites and IoT.

[@1155727]

@@firstnamelastname9918 forget it. The big problem is not the efficiency of the device. The big problem is the very low intensity of nighttime IR radiation. That is a much harder and more fundamental obstacle than finding the right material for your device.

[@firstnamelastname9918]

@@1155727 Low intensity given the current physical conditions of a solar panel, but if you design a system to intentionally store thermal energy that you want to radiate out at night, it's a different story. And I'm just examining the possibilities here. Heck, you could use a reflective panel (mirror-ish) or two on each solar panel, and then liquid cool them storing the heat in an insulated tank and then radiate that heat out at night. Obviously, going to need a lot more photodiode efficiency for that to be worthwhile

[@wesleyjake1509]

Wow that was fascinating thanks for sharing. Love hearing about these break throughs and how they might be used. Just subscribed!

[@petergrossenbacher7372]

A quick look at the Seebeck effect and the associated Peltier effect shows that there are other possibilities, even if some of them date back centuries

[@kxqe]

Yeah, the Seebeck effect was discovered in 1821. However, the Seebeck effect can generate more power per degree-K because it uses conductors instead of semiconductors.

[@firstnamelastname9918]

But isn't the problem with thermocouples it's low efficiency? If I'm wrong, kindly educate me. 😁

[@kxqe]

@@firstnamelastname9918 Yeah, it's low efficiency, but it's better than the "solar" power device they're proposing here.

[@firstnamelastname9918]

@@kxqe Yeah, I dunno. Merriam-Webster defines solar as "of, derived from, relating to, or caused by the sun", so by that definition it is accurate. I feel like I'm going to have to lean towards the author's side a bit on this, though I take your argument. It's better than calling coal and oil "solar power", even though there's truth behind it.

[@eddiedelzer8823]

24/7 power can be made by installing slow speed underwater turbines in all rivers and streams moving 2 to 5 miles an hour. By installing these units below all existing Dams , channels and in fish ladders the World would have more power than most countries could ever use. These units can be moved if needed, won't harm fish, work in coastal tidel flows and yes run 24/7. The Canadian military is replacing diesel generators in the far North with these units, as long as the water is moving work even under Frozen River ice. Using a third of the power made by slow speed underwater turbines can also make drinking water out of the air with atmospheric water generators.

[@johnnydeep7089]

Unfortunately its nearly certain this will not be useful for grid power generation. Solar panels capture a significant portion of ~1000watts per square meter. This sort of device captures vastly less than the black body radiation wattage (optimistically ~450watts per square meter). My extremely generous estimation is that such a device could capture 10watts per square meter. At such low wattage per square meter this could only be useful for grid power if its unbelievably cheap. It is hard to imagine that it could possibly be cheap enough. I suspect any real device would be unable to surpass 1watt per square meter which would require it to cost somewhere around $1 per square meter to be economical.

[@1155727]

Exactly - anyone who does the numbers, even optimistic ones, will quickly see that this is a losing proposition before it even starts.

[@johnmb160]

I think it's a lot less than that. It depends on the thermal heat source and having a cool background. I thinks it's milliwatts per square meter.

[@MikeAG333]

Did you not watch the video? There was no claim it would ever be suitable for grid-scale power generation.

[@EcoHouseThailand]

I have been off-grid with solar and home batteries for 6 years. In the last year I have been using V2L to add extra power into my home solar system at night (videos on my channel) I looked at many options to support the house load at night such as wind power but dismissed them as not economic. What has worked for me is load shifting and V2L. Most people probably only use a few hundred Watts/hour at night so anything that reduces the battery load is to welcomed.

[@1155727]

Surely that should be watt-hours [wh], not "Watts/hour", right?

[@SheilaMink-c2t]

Thank you, Dave. I hope everyone is having a great day or night wherever you are.

[@Imaboss8ball]

This has been accomplished previously through the use of peltier thermo generators and sky cooling coatings.

[@thiemokellner1893]

Thanks. Wouldn't it be much more sensible to insulate buildings than try to recycle the waste heat?

[@nothingbutgianttrees1995]

I'm really sorry to hear people have called you/your videos stupid :( I personally always learn a lot and it fills me with joy to learn about innovations like this. I often share the information with my friends! Any one who thinks themselves smart enough to call another stupid, has already proven themselves wrong. They do not know kindness and its value and that, is true stupidity.

[@GroovyVideo2]

do show on invention of NHIM batteries for EV - patent was bought by BP - they sat on it for 10 yrs - then sold to Chrysler and they sat on it for longer -

[@rickloftus9330]

Dave, thanks for this fascinating video!❤

[@Umski]

2.26mW/m2 vs 1000W/m2 - seems a bit of a waste of time and I do wonder how many fossil fuels are going into that research in the meantime whether it be from the actual lab based work or to the researchers getting to and from work to do it, interesting concept as it may be 🤔

[@1155727]

Exactly! Even if efficiency can be increased massively, this does not look materially more favourable! This tech looks like a losing proposition right from the start. Still good to do the science to build our knowledge and understanding. Just so long as we don't expect any miracles where the bare physics of the affair are against us...

[@RJvanVeen]

As a physics Teacher I loved this idea! Nice work!

[@zapfanzapfan]

The battery from a cell phone would give you more power during the night...

[@peterbathum2775]

right on ! thanks for carrying this story. there's a bit of hope for humans, despite all our worst inclinations ...

[@aguspuig6615]

Im scared that this is gonna get the car that runs on water / cancer cure / stemcell research treatment and just somehow dissapear into nothing despite being promising

[@1155727]

You are mistaken. This is not promising, quite the opposite. It looks unlikely to go much further. There _may_ be some very niche applications. But the numbers just don't add up for anything big at scale, not even with much improved efficiency.

[@Djkudos14]

The most import part of this video is the ide of "no perfect solution, but a broad effort of useful of approaches to chip away our current negative impacts." brilliant

[@12theotherandrew]

OMG! We’ll be wearing electric shirts shortly, Northern Lights shirts on Amazon, glowing sports wear on sweaty footballers. And party wear … that blushes!

[@glennllewellyn7369]

I want my glow sticks really glowing!

[@speters17]

Yep - as with every other efficiency improvement in an economic system driven by profit, this'll just enable us to fuck ourselves over at a lower carbon intensity unless we change that economic system.

[@Kamodomon]

The smartwatch angle is actually REALLY compelling.

[@1155727]

No, it's not. There are already existing solar-powered smartwatches. And this technology delivers so little power that it won't be useful for a smartwatch. Smartwatches, as opposed to "regular" watches are quite power-hungry. The few microwatts this tech would generate from a surface area as small as a watch won't be anywhere near useful.

[@Kamodomon]

@@1155727 Of course. This is super early going and the tech is no where close viable right now. I'm thinking, like, 30 years from now vs next year. It's pie in the sky. But the idea of having a very efficient chip on a smart watch that could just be run from your body heat is REALLY interesting. But, yeah, once again, not realistic as things stand today in 2024

[@ManuFortis]

Sorry, gotta correct you on something. Yes, the GHG's trapping heat can be a bad thing if it goes too far, but that effect is also what helps keep our temperatures from swinging violently like what happens with planets without an atmosphere. So saying it's definitely a bad thing, really overshoots the complexity of the problem as it were. It's like blankets really in a simple way. Just the right blanket, or just enough of the right blankets, and you're comfortably warm. Too many of the right blankets, and you over heat. Similarly a really heavy blanket capable of retaining heat really well will also do this, especially if the ambient temperature is also warm. I.E. It's a balancing act between what is just the right amount of heat retention and dissipation. Right now, we have too many blankets. Not too much of one blanket. CO2 isn't doing it all on its own. Water vapour in the atmosphere also does this, and so does the methane both naturally and otherwise unnaturally released by the earth and us humans. Each one is as effective as it is at retaining heat, and makes them more or less important than the other for managing. We generally need things to eat, and to be able to drink water, so the water vapour is basically good by default. The planet needs it overall. CO2 is part of the food chain as well, like it or not. We simply just need to manage it better. Methane however, is not really needed at all (that I know of) in the atmosphere. Perhaps a small amount of it, to help retain the heat we do want to retain, but too much of it causes that to cascade into a very hot problem for us. Again, if GHG's were entirely a bad thing, then planets without atmospheres wouldn't be constantly either super hot on one side, and super cold on the other. The atmosphere does more than just help protect us from what is out in space. It helps keep us from getting too cold as well. Well, too cold comparatively to the potential extremes otherwise. Let's just say our insulation for our homes would have to be double or triple thick to get through some of those nights. Not winters. Nights. And that sort of building method increases the number of resources needed, and the cost over all. Let's just say it wouldn't be a good time for us humans. People would start using methods to stay warm that environmentalists probably wouldn't like much. Like wood heat to suppliment their gas heat, because it's so dang cold in their home built using petrol products to power equipment and make materials used in the home. Anyways. Sorry again to have to correct you on that, but yeah... this was grade school science class stuff that you got wrong. Not just potentially outdated stuff either. Scientific data that has yet to be proven false.

[@pawelhyzopski6456]

I like Venus. Day or night. Same temps. Co2 is food. More co2 needed 😊 Methane is part of chain. I agree controlling it all would be ideal but we first need to understand the dynamics. All the green movement so far is just pushing agenda to buy something.

[@ManuFortis]

@JustHaveaThink01 Thanks for caring, but you have directed it towards the wrong person it seems. You seem to have mistaken me for someone who needs help, just because someone has the nerve to correct misinformation, intended as such or not. I mean, surely you aren't the kind of person to post a fake help line number, right... person who is pretending to be the channel owner... right? I mean, if you aren't the actual owner of the channel, which I suspect is the case, then isn't it you who needs help, pretending to be someone you aren't? On the otherhand, if this is actually the owner, well... certainly you could do better to actually understand the information being presented, instead of lashing out like a child... Anyways, you have a wonderful day now, and I hope whoever needs that help properly can get it.

[@LuisManuelLealDias]

You're not a fool at all, I always enjoy your videos and commentary which seems very fair and reasonable, going through the harsh environment of super kumbaya tech hype videos or doomsaying pessimism about everything to the other side of just being rational and informative!

[@Guvament_bs]

I am after investors into my perpetual motion machine. Looks like most of the viewers of this channel are a good resource to tap into.

[@scalbaldyfruub7499]

Kudos! Excellent video!

[@dermotdonnelly5495]

Great video as usual 👌

[@jamescappelletti9380]

I really enjoyed you breaking this down to my level. Thank you

[@hugegamer5988]

Fun fact, about 1/3 of the heat coming back out at night is actually heat left over from the formation of earth and internal radiological decay, and not from the sun that day.

[@thekaxmax]

Source?

[@paulmichaelfreedman8334]

@@thekaxmax thousands of geologists that have dedicated their lives to the profession.

[@cornoc]

@@paulmichaelfreedman8334 and what's their source???

[@MightyDrunken]

The Earth loses about 0.09W/m2 from its internal heat and radiates about 400W/m2 at night in total. So what you say is entirely wrong. If it were true, if you put lots of insulation on the ground, you would get some very hot soil, like you get a hot surface during the day from the sun.

[@paulmichaelfreedman8334]

@@cornoc High IQ. Unlike yours.

[@thoriummarcell403]

Yes, the "silver bullet" does exist. It is called breeder reactors. The spent fuel is extremely valuable and useful (not a "waste" as almost always deceptively called), and with fast-neutron reactors the "radioactive waste that has to be stored for thousands of years" problem simple does not exist. (even with PWR technology only 0.0015 kg/person/year spent fuel is produced today - that is world average, 0.008 kg/person/year in USA - 99% of which is valuable and useful and usable either for energy or in industrial processes, like Pt, Rh or Nd). Nuclear energy with breeder reactors (with Thorium or 238-U using material from spent-nuclear fuel as a kindof "catalyst" to keep the reactors operational) is the last great untapped energy source on Earth, that requires 100 times less resources and produces orders of magnitude less waste (including toxic waste and radioactive waste) and produces orders of magnitude more value in useful resources than any other "untapped" or tapped energy source (most of the fission products is valuable and useful, and for each GWyear energy very small amount of waste is produced, much less than other technologies). The amount of Th and U in the Earth's crust is enough for 80 billion years at current energy consumption rate (and billions of years even with increased rate), and unlike solar energy, transporting Th or U from space/asteroids is feasible, so is using them on objects that will be home of life-support systems for most of the next 20 billion years, when the Earth will not be habitable in any way. Th and U are MORE renewable than the resource-wasting weather dependent intermittent renewables that (when sized to 50..80% of energy needs, together with storage) consume more resources and energy than they produce in their lifetime. Not just the toxic waste stream of manufacturing wind+solar renewables is extreme... They will certainly crash the global economy if the nonsense does NOT stop immediately, and concepts are based on sane calculations, not LCOE and lack of calculations (stupidity). See Simon Michaux's calculations. Yes, breeder reactor technology works (eg. in Russia BN-800 and we can do better than that). Why wasn't it built? It was actually built. SNR-300. Built and demolished without allowing to operate. (yes, by anti-environment and anti-human criminal politics, riding wave of stupidity). The title of this video was very deceptive. Please stop deception, because it is a crime. Look into breeder technologies, and compare fairly to fusion and renewables. Even the radioactive waste and harmful substances (Hg, Pb) getting into the environment is much less with breeders than with batteries, wind and solar for a certain amount of continuous power (say 3..5 kW/person for 80 years, that is consistent with modern agriculture, fertilizers and high-standard living).

[@tjam4229]

It’s basically a recuperative heat pump. He flows from hot area to cold area, and you’re capturing energy while it does so. The same way you capture energy from water flowing out of a dam

[@Mrjrich37055]

Very thought provoking as always. Love all that you do.

[@mutantinfant]

Don't forget that clouds act as a thermal blanket and reflect infrared; quite possibly being another avenue of energy production at night!

[@hughbrackett343]

That reduces the ability of the diodes to radiate heat. They would work best against a dark, cloudless sky.

[@junkerzn7312]

Hahahah, "no, don't switch off!". Great line. But it doesn't look practical even if they manage to get high efficiency conversion. 2.26 mW/m^2. 2.26 milliwatts verses roughly 1000W in daylight. That's not just 1000 times less. That's 442000 times less. Approximately. I'm glad they are doing the research though. In anycase, a wifi router burns around 15W. Ignoring efficiencies and running it from a DC source, 12 hours of operation is 180 watt-hours of energy. Which is to say, a very small 15Ah 12.8V LiFePO4 battery. We can scale that up to useful amounts of overnight wattage but it still translates to a relatively small LiFePO4 battery that could just soak up that energy during the day, store it, and dish it out at night. -- POWER DEVICE WITH SOLAR AND A POWER STATION -- $160 - EcoFlow RIVER 3 or similar power station $60 - 1 x 100W solar panel Use 12VDC output from RIVER 3 to power the 12V device. Most wifi routers and other small digital devices use wall power adapters that produce 12VDC. You can run these directly from a power station's 12VDC output instead of using the power adapter if you want. Look at the power adapter for the device carefully to see if it's compatible. Additional tools and probably some 5521 or 5525 barrel adapters will be needed to clip its power adapter and wire in the 12V directly to the device. -- SAME THING WITH DISCRETE PARTS (NO POWER STATION) --- A fun DIY home project that anyone can do on the cheap to run a 12V appliance. Or just wants to get started playing around with solar and LiFePO4 batteries. Quick equipment list. No AC output here, just as the final output (though nothing prevents you from connecting up a little pure sine wave car inverter to the 12VDC battery). $50 - 1 x 20Ah 12.8V LiFepO4 battery (scale-up as needed). $67 - 1 x Victron Smart Solar 75/15 charge controller (can parallel more controllers w/ bigger batteries). $60 - 1 x 100W solar panel (expandable to three or four in parallel with that charge controller) $20 - 12 AWG red and black wire (up to 15A, roughly). $20 - Auto blade fuse kit including fuse holders and wires and a fuse assortment (use a 2A to 4A fuse between the battery and the device as appropriate). $30 - MC4 crimp kit: $30 (crimper, MC4 ends, etc... for solar panel interfacing to the charge controller) $20 - misc butt crimps or WAGOs or whatever you need. Wiring: Solar panel -> "solar" input of Victron Victron BAT output -> battery battery -> fuse -> device to be powered The output can be run to any 12V appliance up to 250W or so. Check the wall warts for your various routers, devices, etc. They usually output 5VDC or 12VDC. This stuff can run 12VDC appliances. Total: $270 or so, not including tools (wire stripper, wire cutter, misc screw drivers, or device interfacing), and not including longer cabling for the solar panel. --- BONUS PROJECT - ADD UPS / LOAD SHIFTING FEATURE -- Bonus Project: For reliable operation of the device in all weather conditions, or to use the system as a load shifter, then you can wire the original power adapter into the circuit to backup the solar + battery when the battery gets low. $8 - 20pcs 20SQ060 Schottky Barrier Rectifier Diodes 20A (can handle 4A in free air without a heat sink). NOTE: Device limit is 50W. Put more diodes in parallel to handle devices that take more than 4A to prevent diode overheating. Connect the original power adapter for device with the negative common to the battery negative, and the positive running through the diode. Take the battery positive and also run that through another diode. The common output from the two diodes (the side with the painted stripe on the diode) can be tied together and then go first to the fuse, and from the fuse to the device to be powered. As long as the original power adapter outputs a voltage in the 11VDC to 12.5VDC or so, the LiFePO4 battery will power the device until it gets too low and then the power adapter from the mains will continue powering the device after that until the battery recharges from solar again the next day. If the original power adapter outputs a higher voltage than this it will act more like a UPS rather because the power adapter will have priority over the solar + battery system much of the time. -Matt

[@michaellucas7177]

Sir, you are no Bozo. I like your videos, disagree with some of your presupositions, but like your research, presentation, style, and consistency. Thank you for your good work.

[@fireball75677]

Solar Nanoantennas would be way better at this, they do however need to be the right length to absorb IR to convert into electricity which makes them unreasonably small, and those have been invented over 10 years ago

[@philplasma]

Once the technology is significantly improved, I can see this thermal energy capture as the exterior layer of the back side of solar panels. Yes, as noted elsewhere in these comments, it would still be a fraction of the daytime electricity, but over vast solar farms, it could continue to generate over night in a place there is already the PV infrastructure.

[@1155727]

Unlikely. At this point, from the numbers, even with vastly improved efficiency, it is most likely that this technology would not even be able to recover the energy needed to make the modules...

[@NightRunner417]

I have long done experiments and design with a project I call "The Starlight Listener" which is really just a tiny solar cell (photodiode) fed into an extremely high gain amplifier. An offshoot of the Starlight Listener is Project DeepStar, which does the same thing but outputs the total light level instead of the fluctuations only. This mad little thing taught me that what I'd hoped is true - it is possible to harness feeble light levels even at night under clear skies, because duh, the moon emits light, nearby cities emit light, the stars themselves emit light, and to a lesser extent various solar and Earth phenomena. And lightning; distant lightning can be detected over 100 miles away pretty easily. Anyway, the point is, there is ALWAYS light available even on the darkest night. All you need is the efficiency to make use of it in electronics. We're already there. It was never a question of "if" you can capture light energy from feeble sources, just how much.

[@ramblerandy2397]

Nice video again, Dave. Solar panels that can capture more wavelengths of the spectrum. That should push the overall efficiency up. Incidentally, a couple of years ago a local relative rang me about his newly installed standard solar array/battery. It appeared to be generating a tiny amount of power at night. On impulse, I looked out my own window. It was a cloudless sky with a bright Full Moon.

[@faithce4936]

Hello, I was hoping you could cover the new article in the guardian titled: “trees and land absorbed almost no CO2 last year.” You are brilliant at explaining more significant topics

[@richardmcdonald7565]

Thank you, Dave, for another wonderful and interesting problem.

[@A.R.O.T.A.]

There is also a device in ham radio, that while still in the early stages of development, has been successful at pulling small amount of electricity out of any radio waves that may be in the air.

[@shawnr771]

Thank you for the commentary, Dave.

[@Beregorn88]

7:27 here, I'll do the math for you, since you always refuse to: 2.26mW/m^2 at 1.8% efficiency means the POTENTIAL energy density is 0.125W/m^2. 125 milliWatt. Per square meter. And that's the absolute maximum you can theoretically achieve. RIGHT NOW, commercially available thermoelectric generators can do 22W/m^2 with that temperature differential...

[@kearneyIT]

great video my man

[@j7ndominica051]

The wristwatch will stop working in summer when there is no temperature differential between the arm and outside. A home wi-fi needs a cable anyway. Maybe a security camera on a remote plot of land.

[@shadowofmyfutureself]

You're REALLY good at this complex reality translation into digestible information Dave Borlace

[@infinitykiyen6270]

This is amazing and i can always smell a great green business