The Mystery Flaw of Solar Panels

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Credits:
Writer/Narrator: Brian McManus
Editor: Dylan Hennessy (www.behance.net/dylanhennessy1)
Animator: Mike Ridolfi (www.moboxgraphics.com/)
Sound: Graham Haerther (haerther.net/)
Thumbnail: Simon Buckmaster / forgottentowel
References:
[1] www.statista.com/statistics/2...
[2] aip.scitation.org/doi/10.1063...
[3] www.nrel.gov/docs/legosti/old...
[4] www.solarpowerworldonline.com...
[5] Page 27 www.nrel.gov/docs/legosti/old...
[6] iopscience.iop.org/article/10....
[7] brilliant.org/practice/elemen...
[8] Chapter 3 www.nrel.gov/docs/legosti/old...
[9] www.sciencedirect.com/science...
[10] Page 14 www.nrel.gov/docs/legosti/old...
[11] www.sciencedirect.com/science...
[12] web.wpi.edu/Pubs/E-project/Av...
[10] www.sciencedirect.com/science...
[11]
[12] www.mdpi.com/2076-3417/8/1/10
[13] aip.scitation.org/doi/10.1063...
Thank you to AP Archive for access to their archival footage.
Music by Epidemic Sound: epidemicsound.com/creator
Thank you to my patreon supporters: Adam Flohr, Henning Basma, Hank Green, William Leu, Tristan Edwards, Ian Dundore, John & Becki Johnston. Nevin Spoljaric, Jason Clark, Thomas Barth, Johnny MacDonald, Stephen Foland, Alfred Holzheu, Abdulrahman Abdulaziz Binghaith, Brent Higgins, Dexter Appleberry, Alex Pavek, Marko Hirsch, Mikkel Johansen, Hibiyi Mori. Viktor Józsa, Ron Hochsprung

[@winterloggan]

Seeing a solar cell on top of a roof in the late 1800s and on a Baker Electric Car in the early 1900s looks straight out of science fiction

[@frogga67]

Hi

[@alwynwatson6119]

The only way to cool solar panels is actively don't fall for thiskzbin.info/www/bejne/fn6pd55_n5uopZI fake news. Batteries are the only way to store energy. Don't fall for this highviewpower.com/ fake news. Also the solar panels are just for show because if they worked they would do this kzbin.info/www/bejne/jYrXg6iFr5mKrNk When did you notice I was joking?

[@jj0493]

Alwyn Watson what do you mean joking it’s true look m.youtube.com/watch/dQw4w9WgXcQ

[@lizardlegend42]

@@alwynwatson6119 Ok bot

[@alwynwatson6119]

@@lizardlegend42 Beep beep hoxs beep

[@thomaslauermann2494]

I worked with three of the cited authors in this video on Gallium vs Boron doped Si to eliminate this degradation in my PhD thesis. Lovely to see it acknowledged and explained eloquently on KZbin 8 years later :-) Awesome channel, keep up the great work!

[@OklahomaLubeDude]

Would this be avoidable if the production was done in a straight nitrogen environment? May be a stupid question, but I know it works in reducing oxidation of hydrocarbon lubricants.

[@Ak3rf3ldt]

What is the best solar panel to use currently?

[@thomaslauermann2494]

@@Ak3rf3ldt Silicon based technologies are still king

[@MeatandTatersGaming54]

Everything I've ever read about solor panels has talked about basically just one frequency , many modern military industrial complex weapons can see and target in multiple wave lengths of light at once so could there be some kind of hybrid silicone we could try that might be able collect electrons from non visible light???

[@Rotem_S]

@@MeatandTatersGaming54 You may be able to separate the infrared to a different panel but you'd need a lot of resources for it to be worth it for just 18% of the solar energy

[@adodoes8770]

I'm an EE student and I'm literally studying a subject with semicondoctors, diodes and transistors now. I'm really glad to actually see all of the theory in play. Your explanation was spot on for understanding the basics. Another great video from one of my favorite youtubers

[@slevinchannel7589]

No Solarpanel-Flaw is bigger than BUREAUCRACY. Theres some real 'Accident-Scandals' where good People just wanted to give back Stuff and arent allowed for nonsense-reasons.

[@KimoKimochii]

what’s a semicondoctor

[@gerryjamesedwards1227]

I think that the idea of floating solar panels, for use in pumped-hydro reservoirs, is a good one. The panels are cooled, and evaporation of the water decreases as more surface area is covered by the panels. Also, the infrastructure for distributing the power produced is nearby in the hydro plant.

[@DownWithBureaucracy]

Except the toxic substances that come off the solar panels over time, specifically heavy metals.

[@BenQuigley]

I have to say, I think the presentation on this one is one of the best yet. And I've always rated you very high up that list already.

[@1rstTry]

I couldn’t agree more. I was a little worried a few months back but this video is outstanding. Niche point but, I watched it on my new oled tv and the video quality is stunning. A LOT of work went into this and it shows. Bravo

[@arnefines2356]

@@1rstTry "A liitle worried", the Nikola video had me unsubscribe in desperation.

[@flymypg]

Agreed! Such a well-made video. And the segue to Brilliant was also one of the best I've ever seen, doing much to convince me Brilliant can be a truly useful tool, beyond supporting idle curiosity or entertainment. The tragic coincidence of Nicola's troubles occurring so soon after the Real Engineering video encouraged me to re-watch the video: All it's major points still stand, despite using Nicola as the example. The biggest risk, also mentioned, concerns the source of Hydrogen, which prior Real Engineering videos have covered quite nicely. Covering both the uses of Hydrogen and its sources are important: We can only hope they meet well enough to make a functional infrastructure possible.

[@mattpeacock5208]

Agreed, well put.

[@krzysiekb.3439]

I could not agree more. Incredible video. The amount of knowledge transferred was impressive, but also the quality of animation.

[@speddelic8742]

That has to be one of the cleanest brilliant adverts yet

[@feruchio599]

quite annoying tho

[@voxelfusion9894]

Whenever youtubers talk about learning new things, I always know it'll be brilliant haha

[@feruchio599]

@@voxelfusion9894 or skillshare

[@zaidahmed5464]

clean so much that made me see it and didn't skip

[@arunpillai3007]

@@voxelfusion9894 or Audible

[@jeromebarry1741]

Thank you! I'd been a tech helping design semiconductors since 1983 and 16 months after you published this video I saw and for the first time learned of "shallow acceptors".

[@brucemccall6539]

SOLAR HEAT FROM 1943: My house, in Florida, had a solar powered water heater installed in 1943. The solar unit was a steel box, about 3 inches deep, with a sheet glass on the face. (This box was about 12 feet long and 2 feet wide, but these dimensions can be as big you want.) This box had a 1 inch copper pipe that zigzagged though out the box, with about 3 inches between the rows. There was also a sheet of copper lining the back side of the box. Both the pipes and the coper sheet were painted black so as to absorb the heat of the sun. The box was placed at a 45 degree angle, facing to the south. The pipe then went to a normal electric water heater, which heated the water on cloudy days. This was a simple, but efficient, system that was still in use when the house was sold in 2009.

[@kylemilford8758]

We had a pool heater like this, basically an analog solar panel 😂

[@xithappens]

Not at all what's being explained in the video, but sure, cool.

[@jonathonharwell1764]

As someone who designs and makes solar cells for a living I have to say I'm really impressed with how well you covered this topic! It's a complicated subject with a lot of subtleties and you did a great job explaining it to a general audience! Nice work!

[@peterfrying4933]

Jonathon Harwell Would love to know your story and how you got into your field!

[@pwnmeisterage]

@ Substances like glass and semiconductors generally aren't recycled. Because it usually takes more energy to melt them down and separate their elements than to just make a new batch. Most electronics recycling is actually concerned only with recovering the gold, silver, copper, and rare earths - the precious stuff - while the rest of the toxic plastic metal silicon garbage is discarded.

[@jonathonharwell1764]

@@peterfrying4933 I'm a physicist by trade and now I work in academia researching new materials and designs of solar cells. I did a degree in physics and basically looked for any research group I could find who worked on solar cells and did a PhD with them (it's surprisingly easy to get into a research group as a phd student as you are essentially free labour. Getting funding is the hard bit!). Now I have a PhD I am (slowly) trying to get my own research group started. It's a tough field to work in and there is a lot of competition, but it does at least have job satisfaction!

[@furripupau]

There is no comparison really, because the extraction, transportation, and storage of coal creates a great deal of waste, and then there is the consequent removal and disposal of ash. Consider also that solar power does not necessarily mean photovoltaic panels, solar thermal plants work on basically the same principle as any fossil fuel powered plant, except the boilers are replaced by solar troughs and heat exchangers. Since solar generation does not require the transport, delivery, and storage of fuel stock, and consequently no rail sidings, docks, etc. (and the carbon emissions associated with all those ancillary activities) all that doesn't even enter into the picture.

[@jonathonharwell1764]

@ TLDR - About 90 % of silicon solar cells go to landfill right now, but this is a big field of research right now so it is likely to improve a lot in the future. -By most metrics solar power wins by about a factor of 10 in terms of lifetime costs of energy production, but this can vary a lot depending on what factors you take into account. Full disclosure - I work mostly on prototyping new materials and designs on the small scale rather than dealing with the large, industrial-scale issues. However I can give you what I have learned at conferences etc. The energy costs of production can vary massively depending on the type of solar panel you are describing, but I shall assume you want to know about monocrystalline silicon since that is the most common kind of solar cell. Thin-film technologies use about 1000 x less material to produce than a silicon cell so they have the potential to improve upon the below stats, but they come with their own problems which i won't go into. Silicon cells are made of about 75 % glass, 10 % polymers, 8 % aluminium, 5 % silicon, and the rest is small amounts of copper, silver, and other metals. There is also a small amount of toxic lead and tin because solar panels are allowed to use leaded solder (unlike most other electronics) so this is obviously also a concern. Currently there are no regulations on disposing of solar cells outside of europe, so about 90 % go to landfill because it's currently not profitable to recycle them. There is a lot of research going into this though because it's a potential goldmine if you can make it profitable. The detailed recycling processes are often closely guarded secrets, but the basic process is you heat the cell up and then peel off the glass panels which make up the bulk of the cell, then you burn away the polymers using sulfuric acid and hydrogen peroxide, and finally you use various acids and chemicals to selectively dissolve all the remaining materials one by one. Hence you can recycle them, but the materials you get out of them are currently worth less than the costs of recycling. Regulation and further research is expected to help with this. It is hard to find unbiased data on lifetime carbon footprints, and it is easy to skew the data by conveniently forgetting certain parts of the life cycle (e.g. the mining costs for coal or the production costs for solar.). Burning coal, you fundamentally get about 340 g of CO2 per kWh of electricity, purely based on how much energy is in coal per molecule and the efficiency of a power station. This does not take into account mining costs or whether you capture the carbon (most places dont capture carbon). A 1 kW solar panel takes between 400 and 500 kg of CO2 to manufacture, and should probably assume that it will only produce an average of about 10 % of its rated output over its lifetime (accounting for night, clouds etc.). Hence this panel will produce about 17,000 kWh over its 20 year lifetime, which works out to about 29 g per Kwh. This ignores the installation costs, space costs, and costs of recycling, but even if these triple the impact then solar still wins. Plus this also doesn't take into account the other pollutants and environmental damage assosciated with coal, so in my view it's hard to argue that solar is worse than coal environmentally. However I'm obviously biased so you should probably look at the arguments I make rather than my own opinion. Solar panels have their own version of Moore's law called swanson's law, where the costs of making them halve roughly every 5 years, so hopefully it won't be long before solar power is no longer a political issue and just one which makes good financial sense. They are already profitable without subsidy in certain places, and once they get cheap enough there will be basically no reason not to integrate them into a new building or whatever (why would you turn down free cash?). It looks like we are approaching that day pretty quickly too! :)

[@dan_draft]

8:23 My name is Bond... Covalent Bond. I'll let myself out.

[@jaidheersirigineedi8110]

MeToo

[@John_Conner222]

🤔🧐🤨🙂😆😂🤣😂😅🤤😥🤯😵🥴☠️

[@highlander723]

I swear to God I just heard a rimshot!!!!

[@sharronkelly115]

Good day Mister Bond👍😲👍😎💣🔪🔫💉💊

[@ObservantAlchemist]

🤣

[@sciuresci1403]

I like how no one mentions the damage done to the environment during the production of solar panels. Nuclear is way more reliable and clean. And thorium is safer compared to uranium. There is a relentless lobbying against research regarding plants using thorium for fuel..

[@markchidester6239]

Until something goes wrong with the nuclear power plant. How much pollution is created then? How much pollution is created with nuclear waste? Where do we put it? Seems that no matter what we do, there is a problem with it.

[@Slicerwizard]

@@markchidester6239 Meanwhile, well run plants don't "go wrong".

[@markchidester6239]

@@Slicerwizard Well the one in Japan sure did. Mother nature didn't seem to like it.

[@Slicerwizard]

@@markchidester6239 Oh, the one where TEPCO didn't bother to protect the backup generators from a tsunami - in a major fault zone? That's your idea of a well run plant? Meanwhile, a dam failure triggered by the earthquake killed more residents than the nuclear plant did. Guess you should start crying about dam construction as well.

[@markchidester6239]

@@Slicerwizard I never said it was well run. My point was that it polluted the planet. YOU said that a well run nuclear power plant doesn't pollute if it is well run. I don't understand how nuclear waste isn't pollution, but what ever. You know all.

[@roberttai646]

This video is one of the very best explanations of the workings of solar cells I have ever seen. I teach teachers how to teach science to tiny kids in an elementary teach education program and this video has helped me understand how solar cells work better than anything else I have come across. I'm excited about sharing this information with my students and helping them develop the confidence to share it with their students. (Just a thought.) There is one thing that should be considered in my opinion. The word, "holes." The understanding that most people have about "holes" is a lack of something in a body of something. A hole in a sheet of paper. A hole in a field of grass. A hold in a wall. "Moving holes" is a concept that does not resonate with many people. No one has ever had a hole in a sheet of paper move to a different part of a sheet of paper. Etc. I know that "holes" are a term used as a short cut for a "position" in the semiconductor lattice that has an overall positive charge. But a student trying to understand this information for the first time can get completely turned around on just this one critical term. I think "holes" needs to be replaced with something else that doesn't have so much conflicting baggage.

[@thelistener1268]

That was THE BEST transition into a sponsor I've ever seen.

[@cupiduspacis4209]

Indeed, it was pretty impressive! It worked too, as I'm now inspired to check it out.

[@alainspecteur1]

yes, it was "Brilliant"

[@TristanVash38]

This was the perfect rick roll that I watched all the way through. I clutched my chest and said, "omg he got me at 100% efficiency to watch the ad versus 18% with Linus Tech Tips."

[@anthonybomberry9935]

Amen

[@anthonybomberry9935]

Amen

[@alexanderkrneta8032]

This is the best brilliant advert I have ever seen.

[@EchoBuildsThings]

*most brilliant? 😁

[@styx5062]

Asa9 I think he’s talking about the website brilliant

[@WokerThanThou]

Yes, but ... I can't take a product seriously when it uses the "first x amount" of people get extra stuff scam.

[@_Amilio_]

a most perfect segway

[@PunzL]

@@_Amilio_ *segue

[@llindamarisol]

I really love absorbing as much information as I can on these solar panels. It’s a great industry to be a part of

[@jz-ez7wx]

Very cool to see the robot arms I used to teach the wafer loading and handoff positions in action, the semiconductor industry has really opened my eyes and encouraged me to pursue a more rewarding career in the industry

[@sayethwe8683]

Already watched it on nebula, but giving you those interaction points here too.

[@hkr667]

I really don't like Nebula that much and still watch all the videos on youtube.

[@renanmendes1299]

@@hkr667 You can abuse the free trial on nebula tho

[@IncroyablesExperiences]

All is extremely well explained, thanks! I thought the 19th century solar panel was a joke, it blows my mind! Way before the photoelectric effect was explained by einstein. I love old innovations of the late 1800s, they just tried everything about energy vs mobility (trolley, comprenssed air, kinetic, and so on.)

[@TheOneG36]

Becquerel and Hertz discovered it decades before Einstein, what Einstein did was the Planck constant with you guessed it Max Planck.......... (the quasi scale for Quantum Mechanics)

[@RandomGuy0400]

Well the 1800's solar panels were real, you aren't wrong in thinking they were a joke; they actually kinda were, having an efficiency of only around 1%

[@AD-kv8iu]

@@RandomGuy0400 I think not appreciating their curiosity and innovativion is a tasteless joke . Now that your armed with a lot more info it seems that way. Think about it If you were to meet yourself a 100 years later you can go on ranting you could have done this and that and what not but the fact is that was the start . At that time the electron was not experimentally verified ... It was a different era . Electromagnetism was just picking up the pace .

[@michael.forkert]

Exactly(!), the great masquerade begun at the beginning of the 19th century, which transformed planet’s societies into what they are now. It transformed Monarchies into Republics, which replaced all monarchs, convincing peoples on earth, through misleading propaganda, that even the good monarchs were blood thirsty plutocratic tyrants. The great masquerade led initially to the First World War, which began 1914 and ended in 1918, and during this period of caos, the Soviet Communist Revolution (1917) was also achieved, by the Bolsheviks led by Lenin, Trotsky et caterva. The great masquerade did not replace the totality of European Monarchies with democracies. In reality it transformed monarchies into communist, nazi or fascist dictatorships, what lead to the Second World War. After the end of WWII, began the implementation, and consolidation of communist regimes throughout the world, (e.g. Iron Curtain, China, Korea, Vietnam, Cuba, just to mention the most important), which was achieved by a blood bath never seen in beforehand in the planets history.

[@danecrude]

@@RandomGuy0400 100 % better than the one they try just before the one that worked

[@jcgoogle1808]

That was the smoothest continuous segue into and ad I have ever seen. I mean the ones you typically get hit with come at you with cheap slap stick cliches you can see coming from a mile away.

[@solargoat]

Pretty cool to take a time machine back to see how old solar panels used to work. All the stuff I install now is boron free in the doping process and doesn’t have light induced degradation.

[@ThomasLee123]

Love your description of basic electronic theory. P-N junctions are what makes transistors and other devices work and almost no one in our population knows this basic information. Thanks again.

[@palapafox1268]

12:04 Nature: you couldn't live with your own failure and where did that bring you? back to me.

[@BrutuxMusic]

"Failure" I'd like to see anyone or anything do better

[@electronresonator8882]

​@@BrutuxMusic watch this video kzbin.info/www/bejne/eJrGnIB8faaNiJI "How Trees Bend the Laws of Physics"

[@TheIcyhydra]

look at that worm eating the leaf....that's called natural selection

[@carso1500]

We take a lot of inspiration from nature, taking what it has created learning from it and perfecting it

[@TheIcyhydra]

@Renato A dude, nobody mentioned chineses, i think you can rest assured...lolol

[@NickRoman]

This explained how solar cells work in a way I don't think I've ever heard before. It's interesting that your intention was to explain a certain flaw, but better explained the fundamental functioning better than anyone else (that I know of).

[@Pingviinimursu]

Finally an excellent way to tie in the sponsor. I saw it coming before you mentioned brilliant, but that didn't matter. What mattered, is that for the first time I've encountered, you showed an actual problem that you solved with the help of brilliant. This might not be a problem I'm facing, but this type of tie in still deserves a ton of more respect than the usual bad puns that are so common with sponsors. Good job!

[@Fabelot1]

This is the best visualization and explanation of semi-conductors that I've ever seen! Thanks for always bringing interesting topics :)

[@zaidahmed5464]

actually I have this topic in high school never understood it like he did explain also when he's talking about fermi level I strangely understood it, the way he explaining things are "brilliant"

[@z3lop59]

But it's not quite right, he misses a few points in the pn transition.

[@jaketyler7088]

@@z3lop59 It's good enough for a short solar video. There are entire college courses devoted to semiconductors; not the easiest to fully explain in three minutes.

[@ReachOutToWilliam]

@@zaidahmed5464 Quick, Watson! The vomit pail!

[@AstralS7orm]

This is high school chemistry level presentation though. The physics is not actually fully known here. (Go ask about Quantum Hall effect, and that's the more known part.) The electron-hole model is known to be an invalid approximation.

[@pace7746]

That was a Brilliant transition into the sponsor.

[@godfreypoon5148]

@Renato A oh yeah, totally

[@nofthet5548]

@ 0.1% .....who hurt you ?

[@thedude4039]

Kind of ironic huh?

[@richardnixon5710]

@01 % ok ok m8 this was about solar cells and advertising you might be on wrong site i think you might be looking for UP IN SMOKE by Cheech and Chong or some other more " plant " based site

[@charlesdomalewski7817]

That was the most incredibly subtle, efficient segway to an ad I've ever seen. Kudos! Well done.

[@grantperkins368]

Segue.

[@charlesdomalewski7817]

@@grantperkins368 Thank you.

[@sarahmandel7179]

Very nicely explained. The Brilliant segue was so smooth. I managed to catch it as it was happening. That's always the bonus part of the video. Thumbs up.

[@Bob_Adkins]

Dust is a highly underrated problem on solar panels that I never see mention of in panel efficiency. It necessitates very hard, very expensive labor to keep up with dust settling. Simply rinsing is not enough, the panels must be rinsed with distilled water or well dried to prevent lime deposits. Improperly drying panels with tap water will make them lose efficiency permanently, so workers must be well supervised.

[@KarldorisLambley]

must the worker's supervisors be supervised too?

[@robinspat]

Now consider solar panels on liveaboard boats, sea water ;)

[@Bob_Adkins]

@@robinspat Good thinking!

[@RevAnakin]

I recommend visiting any other power generation plant. The sheer volume of skilled workers is significant compared to the few people needed to "wash the car".

[@Bob_Adkins]

@@RevAnakin There's one just down the road from me, and yes it does have a lot of highly paid, happy, skilled workers with 401Ks.

[@IsmaelAlvesBr]

Yes guys! Photovoltaic cells are just diodes with the sun

[@philipschloesser]

I mean... They're also just diodes

[@kraziecatclady]

I've been saying that for a pretty long time now.

[@gelatinocyte6270]

They're LEDs in reverse

[@ColinTimmins]

If you power the solar cell, it can work as a very crude LED, providing IR I believe...

[@philipschloesser]

@@ColinTimmins not if it's made of silicon. Silicon has an indirect band gap, which makes it unusable for LEDs

[@ADEpoch]

You explain why we need your sponsor better than most other Channels (even for the exact same sponsor!), probably because you are being honest about what you know and don't. Thanks.

[@This_is_my_real_name]

Instead of anti-reflective surface treatment to _block_ reflected light, what I'd do is _enhance_ its reflectivity -- but do so selectively. I'd use a dichroic reflector that would _pass_ that part of the spectrum for which silicon cells are most effective (blue), and _reflect_ the _rest_ of the spectrum (green, red, infrared) -- which would have two benefits: It would prevent the photocells from heating up so much, and, it would allow the heat to be _captured_ for a _secondary_ power generation system (i.e., the central _"molten salt tower"_ concept as used in the Sahara).

[@vikraal6974]

Lmao, using only blue light makes the problem worse. You'd be getting even lesser than 10% efficiency

[@This_is_my_real_name]

@@vikraal6974 -- Yawn... then pick the best color. Case Closed. PS: Decades ago, when I had a camera repair store/shop, silicon photocells were introduced as a replacement for the then-universal CdS (resistive) photocells. They were as I recall described as "silicon blue" cells that required filtration to counter the silicon photocell's blue sensitivity. I guess the technology has changed in the past nearly half-century. Go figure.

[@thomaswinstonmontague9272]

@@This_is_my_real_name "prevent the photocells from heating up so much" Photocell heat is not a problem in real-world installations. "Yawn...Case Closed" Your imagination isn't the final arbiter. "photocell's blue sensitivity" So the blue light was filtered OUT, while you want to filter red and green light OUT. Nonsense.

[@ChillinwithLandD]

Irish people say “t’reshold”. Hmm, interesting

[@James-cb7nb]

M'lady

[@nizm0man]

I see/hear nothing too unusual

[@dell899]

they are also scared of heighth

[@johnc7385]

Irish people swallow the h on most words. Thanks becomes t'anks, three, t'ree, think, t'ink and so on.

[@Hissmannen]

First, second, turd...

[@italianbillclinton5582]

Would love a video about why solar cells do poorly in heat if you’re up for it

[@RealEngineering]

As soon as explanations go into quantum physics, my brain is incapable of understanding. Not smart enough for that shit

[@gabrielbloch8837]

@@RealEngineering understandable, have a nice day

[@craigwall9536]

@@gabrielbloch8837 Silly. Increased temperatures mean increased electron energies which mean increased chances of electron _tunneling_ across otherwise insulating junctions. IOWs, increased temperatures mean the damn thing gets "leaky" in places where that leakage loss should be low. Put another way, it starts to _hemorrhage_ electrically.

[@tommegg8486]

@@RealEngineering well that does mean you should go back to that Brilliant course

[@MrSparker95]

@@craigwall9536 Thanks for explanation. Silicon devices degrade with temperature a lot (exponentially!), one can check a datasheet of any seniconductor device (diode or transistor) to see. No surprise it also affects the solar panels.

[@DrinkingStar]

I thank you for explaining quite nicely and simply how solar cells work. I will be viewing your video several more times so as to catch some of the things that I know I missed on just this 1st viewing. Because of the future of and need for "green" (= carbon free) energy, I have been doing much research ( reading and viewing videos) on solar cells and hydrogen fuel cells(batteries). From what I can tell, the energy created using solar cells can be use to release hydrogen from either water or ammonia. Ultimately, the energy associated with this free hydrogen can be stored in fuel cells. Fuel cells batteries can store more energy than lithium based batteries. Lithium is considered "grey" energy and because of mining, it is environmentally destructive. The same cannot be said about water and ammonia which are considered green energy. As a result I have been investing/speculating in both types of ventures(solar cell and fuel cell manufacturing). Below is an excerpt of a news article that relates to the current efficiency of solar cells. Zacks Equity Research Fri, July 16, 2021, 8:44 AM In this article: JinkoSolar Holding Co., Ltd.’s advanced high-efficiency solar module recently set a new record by attaining the highest conversion efficiency at 23.53%. Its large-area N-type monocrystalline silicon solar cells have also set a test record of 25.25%. P.S. JinkoSolar is one of the companies in which I invested.

[@paulfiore850]

Excellent article. In Upstage NY I see solar farms covered in snow on bright, sunny days. I'm completely off grid and I can tell you that there is zero power produced when panels are snow covered. Must lose enormous amounts of energy after a snowstorm

[@freetvable]

I'm in Northeast, we mounted panels on our south facing walls! No snow! Plus snow reflection causes massive power. We are offgrd also 12+ years.

[@paulfiore850]

@@freetvable Where in NE? I'm in Southern Adirondack mountains upstate NY

[@SnowyValk]

I tried to tak a course on brilliant on solar energy but i just started 8th grade so i didn't understand most of the things there but you managed explain in a way that even i can understand some of it you are amazing

[@DiracComb.7585]

I did a paper on photovoltaic cells for a class I had this summer, gotta say, kinda wish this video was released then, still, great work

[@chippysteve4524]

Brilliant.org was around. ;-)

[@abhijitborah]

Kudos: Great video. Band gaps to knowledge gap to becoming brilliant was in a never seen or heard before method.

[@patmaloney5735]

Im really grateful for channels and individuals such as real engineering.

[@bobgreene2892]

I just discovered this channel, and am amazed you do not "water down" the content like so many other, popular video course streams. We not only need, but seek a challenge, and this approach animates everything about Real Engineering-- there is always a rewarding surprise, in store.

[@EXtREMeBuLLsHyTS]

I am a PhD student working on semiconductors, specifically on large area electronics (PV solar cells are in this group) and i totally recommend this video on this topic. Well done Real Engineering! Big thumbs up from me! 👍🏻 (Also subscriber of your Nebula channel)

[@andrewdavis6012]

Germany is held up as the world’s solar and wind capital by “renewables luvvies” but Germans are freezing through winter due to “millions of solar panels blanketed in snow” and turbines sitting idle,no wind this is happening now

[@sunshine7453]

This is the best explanation of solar cell together with the graphics. It takes a lot of efforts. Thank you!

[@ryuuguu01]

I enjoyed this and it was the first Brillant ad I have seen that made it sound useful. Usually, ads talk about teaching basic stuff to people with no science or math background.

[@renownerd.276]

Is it just me or is he talking slower?

[@RealEngineering]

I hosted a TV show in Ireland and I think they may have knocked the fast talking out of me.

[@WarrenGarabrandt]

@@RealEngineering It's a difficult balance of talking fast enough to not drag on, and not talking so fast that people can't understand you. I think you're struck a pretty good balance here. You might be able to go up be 20% or so, but I definitely wouldn't go any slower. Thanks for the quality content though. :D

[@renownerd.276]

@@RealEngineering Video was still great and informative, so it didn't really detract from the experience.

[@victorang928]

@@RealEngineering woahhh

[@Redstoneghost133]

play it at 1.25x speed

[@ororc]

I've worked and researched in solar in several years and I'm super impressed that you were able to create such and excellent and detailed introduction to photovotaics after a couple weeks of research. This is so clear without skipping on vital details. There only thing that bothered me was that silicon does not balance spectral constraints the best. Thr ideal bandga0 for a solar cell is 1.3-1.5 eV

[@nickbaires2864]

Thanks from Buenos Aires Argentina. I subscribed to your channel. My calification is genius level. And the information you provide in this video is a guide to buy the better technology in solar cells to install in houses and facilities or even vehicles. This year I'm gonna buy a system to install in my house. Of course there are another components like batteries, charge regulators, power and voltage converters, large section diameter copper wires, installation in combination with public power supply.

[@danpacleb790]

Nicely done. I applaud you for providing insight and understanding. Question - as solar technologies age (panels) and are replaced, these old panels...how are they disposed of? Do they provide a real hazard to us and the environment. Much like the disposal of CRT tvs and computer screen, computer components themselves, nuclear fuel and even the cars and its components, we've learned its disposal provides hazards. For all its good intended values do the solar technology components have a 'dark side' in its after life.Is this too being managed?

[@thefeds7462]

No one really recycles old panels as they are past use by dates. So, disposing of panels is a massive future issue. Not to mention 2 things the Greenies will not mention. 1. The resources needed from the planet to build them. Simply put we need to rape and pillage the earth so it is probably more environmentally friendly to stick with coal fired plants or nuclear 2. And destroying acres of land to put solar farms is just dumb and defeats the purpose. Then to this add electric car manufacturing. What a environmental catastrophe that is. Refer to recent talks from Manhattan Institute。

[@miked7923]

I'm taking a solid state devices class right now and you are 100% correct in the fact that they assume you already know advanced topics and skip over steps.

[@jansenart0]

Still waiting on the rest of that Space Elevator analysis.

[@CaptainSeamus]

A space elevator would be great!!! Just read the Red Mars, Blue Mars, Green Mars trilogy to see just how "great" they could be...

[@zorro19934]

Great video! Very informative. And the solar energy course on Brilliant is also very good and helpful.

[@bullettube9863]

I still have a solar cell I used on a crystal radio I made in high school in 1967, it's output is hilariously puny compared to the solar cells recharging the batteries on the garden lights on my balcony. But I learned the basics of both solar technology plus how radios worked. I later made my own transistor radio, I had to make the printed circuit board, install the transistors, and fit it all into a small plastic storage box. The speaker and battery were the biggest parts, plus some space set aside for the ear bud. It worked and a couple of years ago I took it out, installed a new battery and let my grand-daughter play with it. My question is, why did schools do away with industrial arts, or as we called it; shop?

[@markchidester6239]

I wish the highschool I went to had a program like that. I would most likely be in a better position now.

[@BaltimoreAndOhioRR]

They had to make room for Gender Studies and Critical Race Theory, that's why.

[@bullettube9863]

@@BaltimoreAndOhioRR No that is not the reason. Critical race theory is not taught in high school, it is an optional course in college only. Too many people thought that the future was in computer use. I told the local board of education in 1980 that in the future everyone would be able to use their own computer and professionals would not be needed. They didn't listen to me and continued to teach data processing which soon became useless. While math and science are very important, not all students are Einsteins. History, music and art are also important, and kids should learn basic skills in using tools and how things work. Thankfully more and more schools are coming around to this idea and bringing back industrial arts and vocational training. AND in addition learning how to be tolerant of people who aren't like them.

[@stopvoting4oldppl952]

Education budgets keep getting cut. Your only gonna find shoo available in upper class neighborhoods and charter schools

[@altoticket]

There's actually lots of deep research for this video, what a treat you presented us with! Thanks!

[@nicoz4122]

Amazing content. Super clear ! The PV panels are a complicated matter that mixes mathematics, Physics and some chemistry. This content is important to explain in less than 15 minutes what is the current state of the PV panels, the limitation, efficiency and even a little bit the possible future evolutions. Great content ! Keep on the good work !

[@pieteruys2032]

You need to discuss the vast tracts of land that have to be given over to the renewable power sources. What is the lifespan of the panels and how will aged panels be disposed of?

[@chrisbusenkell]

another great video, thanks so much for all your hard work. it is most appreciated.

[@michaos1]

I truly like how you put your sponsor messages. It's even fun to watch so I won't skip.

[@cdl0]

N.B: selenium cells generate electricity by the photoelectric effect, which is not the same as a in a photodiode. An important factor not considered in this video is that silicon has an indirect bandgap; thus, the generation of an electron is necessarily accompanied by a phonon (lattice vibration) which represents another source of inefficiency. This is a fundamental property of the material which cannot be altered. Also note that oxygen is an intentional impurity in silicon made by the Czochralski method, which makes the wafers stronger. Without oxygen, large wafers would be too weak to handle during the manufacturing process.

[@Blue1Sapphire]

If only I understood u.

[@gamesbond2733]

@Renato A wtf ! We were taking about solar cells

[@msb3235]

Yup you're correct. That's why now we (Solar cell researchers) are moving on from Silicon based Solar Cell to 2nd Generation thin-film and 3rd Generation organic Perovskite Solar Cell. Both are direct bandgap and can be built thinner and more flexible.

[@EXtREMeBuLLsHyTS]

@@msb3235 true. But the organics and perovskites are way too sensitive to atmospheric conditions. Exposure to the air and humidity instantly kills them. They need proper encapsulation which further reduces efficiency and increases cost and manufacturing complications. Inside labs these materials are only worked on in a glove box. Sadly we have yet to reach a breakthrough. Cuprous oxide was once thought of as a good candidate but seemed like that research direction is no longer present.

[@cdl0]

@@EXtREMeBuLLsHyTS & @MS_B Both true! It is a really tough problem. Silicon, as you well know, is cheap as chips, and it works, so if you have the space, then it is not a great hardship to add some extra solar panels to compensate for low efficiency.

[@bergfpv6486]

Your segway into the "Brilliant" ad was brilliant. Great video.

[@Redsson56]

Great job. I am also an Engineer and am a believer when serious technical resources are applied in several places consistently there will be progress. Apparently more than $200B/yr will be spent on photovoltaic by 2026. Question: how much land area will be dedicated to solar energy?

[@v.gedace1519]

Very nicely made video! Would like to give you a second thumb up for the fact that you clearly say that you have some missing knowledge to explain it 100%. This makes you likeable! And you explained it well enough to have now a much much better understanding whats going on in these cells! Thank you very much!

[@gangleweed]

Yes, but without the complicated explanation of how the things work, the fact that they do work in large numbers even with some deficiencies means the future with them is still very bright.

[@stevenalcantara1451]

I can feel the satisfaction from how you first said the energy (Si = 1.1eV) needed to push out an electron from it’s valence band to it’s conduction band then, later revealed that it was a surprise to you when you first read “band gap”. ❤️💯 For those asking, a simple explanation of band gap is the distance (in terms of energy) of the valence band to the conduction band. Think of the valence band as the ground state of an electron around an atom and conduction band is when that electron is energized out of the shell “ENOUGH” for us to be able to use it.

[@jimgraham6722]

Thankyou. I have noticed my solar panels get lighter in colour as they age. It seems UV is bleaching them. That said I have found they get twenty years useful service at 80%+ rated power. They do accumulate damage though. Hail, lightning (both flash and strikes) cracked wafers and cracked covering glass, corroded frames take their toll. By twenty five years most have a fair bit of damage and need replacing. My oldest panels still working are thirty years old. I have one that is thirty five years now being used as top of a coffee table.

[@salvatorecali9687]

The main issue with PV panels is that they only work, obviously, if there is sunlight. When there's no sunlight, nor wind to use wind turbines, you have to go back using traditional energy sources. If we want to get rid of fossil fuels, the only solution to this is to increase nuclear power and only intermittent renewables to cover the daily peaks in electricity demand.

[@amcluesent]

TBH the sun is a bit overrated. At least the moon gives a bit of light off at night. The sun only shines in daytime, when it’s light outside anyway so it is.

[@123pathTube]

Lol

[@YodaWhat]

Very droll. For your next one, try the student trip to the Sun. They have to go at night, when it's cooler.

[@ayushagarwal7631]

"iT Is LiGhT oUtSiDe DuE tO tHe SuN oNlY aNd ThE mOoN rEfLeCtS tHe LiGhT oF tHe SuN. tHe SuN iS tHe SoUrCe Of AlL EnErGy DuMbAsS" - Someone probably

[@ileksoku]

Nicely done sir

[@e1123581321345589144]

@@ayushagarwal7631 there is much power in the light of the moon, for 'tis only under the pale silver light that we can unlock our true nature. The sun sits out more energy, yes. But it's energy is destructive to us. It interferes with he bio-chemical bounds which enables our transformation. - some werewolf

[@timmonapier8832]

You are a great advert for the course. Thank you for taking the time and effort to produce this vid.

[@Eat_Ride_Sleep]

This was an excellent, digestible explanation. Nice work.

[@TheRoidemortetfleur]

I saw one video that added groves. A row of plant then solar then plants. The sweating of the plants keeps the area cooler. similar to adding a fountain to an outside area

[@marcozorzi6770]

20% efficiency is for panels installed on a dual axis solar tracker. In a fixed position installation a realistic efficiency conversion rate is around 14% , taking into account the incident angle modifiers, plus losses due to external temperature, cables and inverter.

[@lorenwilson8128]

All solar cells underperform their stated (nameplate) power generation rate. Typical actual production rates are about half of what the solar cell is rated to produce. This does not include the fact that they only work about half the time. They also slowly degrade over time. While they are appropriate in locations where more reliable power is expensive (islands without fossil fuel resources) they are still much more expensive than a gas turbine or coal-fired power plant.

[@pbajaj]

the 14% is history long ago. panels are now delivering 19% efficiency on static/fixed tilt systems.

[@marcozorzi6770]

Prem Bajaj sure, this could be possible using a premium brand and panels that are at the top of the range, which possess the best efficiency rate, low degradation over time and longer longevity. Certainly these premiums come to a higher capital costs compared to the average panel used in commercial applications.

[@marcozorzi6770]

Loren Wilson good points! We have come a long way but we certainly need to improve their quality, conversion efficiency and reliability! Let’s hope we can achieve that in the near future as we really need to move away from all forms of fossil fuels.

[@pbajaj]

@@marcozorzi6770 Hi Marco. Knowing fully well a 25 year production outlook. and minor variance in price/kw, but much superior efficiency and generation, lower degradation levels - think the price setoff on cheaper panels doesn't cut the objective of transition for those getting later into the market. Lets not forget, todays market, installing poly 300-330W panels, is already a 5 year old technology (why carry forward another 25?). Surely there are regions where they can be utilised - but not in enterprising / dynamic economies. This' like continuing sales of ICE vehicles thru till natural downfall - which just may not happen?

[@nicodiveira]

What an amazing video. I'm an Electrical Engineer and I did a course during my graduation about photovoltaic energy generation and yet I didn't knew about all of this theorical limitations of the so photovoltaic cells. I use to thought that the low efficiency was due to technological limitations. So, can we all agree that fission nuclear power plants are the best way to produce clean energy by far?

[@hairyhothead3006]

We are currently looking into covering our roof with solar panels, apparently you can buy solar panels that are cooled, which in combination with a heat pump can also contribute to heating the home for a significant amount.

[@iHelpSolveIt]

Hybrid panels also help keep the panels cool, this improves the solar panel efficiency. Remember to get individually rectified panels, smaller cells also help when panels fail and to cover more of the roof

[@DrakeyC]

Excellent video, I appreciate the in-depth explanation of how solar panels work. My takeaway is that another area we should look at; if the grid-design for solar cells is causing an 8% loss of efficiency, then we're only tapping 2/3rds the power we could from solar cells. A more economic way to create more efficient patterns for the metal could be a solution, but perhaps a conductive material that is semi-transparent could also reduce the loss. Of course, I'm no engineer or scientist, etc., so I've no idea if the latter could even be done.

[@waylandsmith]

It's 8% of the total 80% loss, not 8% of the 20% remainder. So improving it would definitely be of value, but would not reduce efficiency losses by 1/3rd as you imply. And there do exist transparent conductive films (TCFs) but what's holding them back from wide usage in PV cells are cost, but apparently that is improving.

[@DrakeyC]

@@waylandsmith That's what I meant with the 2/3rds comment - if we could tap that 8% successfully, we'd achieve 28% total efficiency, compared to 20% now.

[@jimmyhack7336]

Some high efficiency solar cells get around this problem by putting all of the metal grid on the back side. But this doesn't work if you also want to collect light that hits the back side (which is becoming more popular). There is also a lot of work using transparent conducting materials, but most silicon cells still use a metal grid.

[@shaqibkhan5392]

10:45 slight correction here, actually electrons move from n-type to p-type and also from +ve terminal to -ve terminal. What you have shown is direction of flow of current, electron flow is in reverse direction of current flow.

[@w0ttheh3ll]

actually the animation shows exactly what you just described.

[@Lostsage01]

Great video, and this has been a strange problem. Although I would add that the biggest issue with solar power isn’t panel efficiency (although improving it would certainly help) but actually storage technology since power production is intermittent throughout the day. If we can develop a better battery that doesn’t have the limitations of lithium ion tech, etc., that would allow us to to build economical utility-grade storage plants that could supply on-demand power needs at all hours. Until then, the limiting factor of a 100% renewable grid in the US is still the need for stable baseload power, which means either fossil fuel sources or nuclear.

[@1SmokedTurkey1]

Yep. I'm an Electrical Engineer. We care less about efficiency and more about storage when it comes to practical applications. After all, batteries are much more expensive than solar panels and solar panels are efficient enough these days.

[@elgracko]

what about using all that surface area to sandwich an insulating material between two conductors to create a parallel plate capacitor behind the solar panel?

[@tomwebster2494]

Superb video and what a fantastic advert for Brilliant. I've never been tempted to actually look into a sponsor before, but I'm heading to the Brilliant website now.

[@brianmuhlingBUM]

YOU'RE MAKING IT UP! WOW! I could not believe the complexity of PVC until I watched this great or should I say BRILLIANT explanation. It is well above my intelligence. Here in Western Australia the uptake of PVC's is huge because of our many hours of cloud-free daylight each year. Soon all new houses, factories and offices will have PVC energy. Regretfully, I won't be around to see it happen ..but it will?

[@thomaslebreuilly7891]

Great video, on an important topic applicable to the vast majority of currently available PV modules (mostly mono PERC). Just a small correction : typical LID of modern PV modules is 2%, meaning that after initial sunsoaking the PV module performance would be 98% of its initial one. So 98% of the initial ~20% efficiency. Which means a 0,4% decrease of efficiency, not 2% decrease. In terms of energy production the loss due to LID is then 2% and not 10%.

[@foxyvisionsvideographer]

that's right, just after 30 years it reduces to 18%

[@deus_ex_machina_]

@Randy Alvarado But that drop-off is almost certainly not linear, is it? That doesn't really mesh with what we see elsewhere.

[@thomaswinstonmontague9272]

@@deus_ex_machina_ The loss is .5% of the remaining efficiency, meaning multiply .5% times the current year's efficiency, and subtract that amount to get the next year's efficiency. So it is exponential decay, not linear.

[@thomaswinstonmontague9272]

@@randyalvarado6401 The solar expert meant to say "the panels would have 50% of their initial efficiency" or they would be only half as efficient as when they were new.

[@jessecooper9093]

That was a masterclass in how to transition into an ad. Hooked me so well I wasn't even upset I had just watched an ad, not gonna lie.

[@davidbruce2159]

Commercial solar power is a CANCER on the planet. The technology when paired with the use of FAKE money causes a wealth transfer from the working class to the elite class. Be careful of what you wish for.

[@davidbruce2159]

@@zucadasilva937 Solar panels cause Toxic waste during their manufacture. The resources that go into the manufacture and installation of solar panels, require mining companies to pollute and burn hydro carbons, like diesel and gasoline. The mining companies dig holes that don't need to be dug. The panels have a 25 year operating life span, then part of the solar panel ends up in the land fill forever. YUCK, I don't like toxic waste.

[@listerdave1240]

Perhaps you need to compare that toxic waste against the amount of toxic waste that is prevented by reducing the amount of electricity that needs to be generated by other means.

[@davidbruce2159]

@@listerdave1240 Let's not forget that the main ingredient, silica, is made by Mining high purity quarts and mixing it with coking coal, and then firing the mixture in a electric blast Furness. I also submit that the thermo/electrical energy consumed is also greater that the pannel will ever produce in the pannels life cycle. You people need to come to your senses. You are destroying the planet when think that your helping it.

[@listerdave1240]

@@davidbruce2159 I think you may need to recheck and/or update your calculations with regards to how much energy PVs produce compared to the energy needed to produce them. What you state would have been true about forty to fifty years ago. Today it takes well under a year for a typical PV to offset its carbon footprint. Also, if you were to consider the carbon footprint of building a standard thermal power plant (coal/oil/gas) you will find that even building the thermal plant has a higher carbon footprint per megawatt of capacity even before it starts consuming fuel to produce electricity. Thermal power plants need vast amount of steel, concrete and other materials produced in blast furnaces, kilns and such. The only issue with solar panels is that they currently only offer a partial solution and therefore can only be used to substitute part of the fossil fuel production rather than all of it. That is likely to change very soon though with the introduction of liquid metal batteries and possibly other storage systems.

[@abloogywoogywoo]

The final nail in the coffin for solar panels for me was the fact that their thermal efficiency drops when they get hot. I mean, what is the freaking point??? You mow down the desert's natural habitat and vegetation (yes there is life in the desert) to stick acres of panels there, where sunlight is abundant... and they don't work.

[@sirnikkel6746]

Thermal exchange: *bonjour*

[@antontaylor4530]

That's not exactly a "final nail". Even with the loss in efficiency, solar is still the cheapest way of generating electricity. Plus, as stated in the video, you can cool the cells. I mean, he actually states in the video what they do to recover some of the efficiency - not sure why you are ignoring that. Thing is, in cooler countries such as England or Germany, Solar PV's can be extremely effective and crazy cheap. My father-in-law has solar on his roof, and it's bonkers cheap and very effective. I'd have it on my roof if I didn't live in a ground-floor flat with no access to the roof. Plants are less than 2% efficient. Anywhere that plants can live, you can be sure that solar PV will work very well.

[@abloogywoogywoo]

@@antontaylor4530 I get the feeling you're talking about something completely different. If not, what are you on? Solar Panels are NOT cheap. They have large amounts of high-purity silicon which is expensive to manufacture. They require installation from qualified workers (you can't set these up yourself, because otherwise you could screw up the inverters and electrical protection).

[@antontaylor4530]

@@abloogywoogywoo I'm "on" reality. As I said, we just installed Solar panels on my father-in-law's roof. Just over €100 per panel, 200w per panel. It wasn't difficult and we didn't screw anything up. Probably another few hundred euros for the inverter, batteries, brackets, power cables and charge controller. Your assumptions are wrong, and show very clearly that you don't have real world experience with PV. You're making assumptions and then presenting those assumptions as if they're facts. They're cheap. At the rate that dad's panels are making power, the system will have paid for itself in a year or two, and then it's free electric for another 18 or more years. If you think solar is expensive, then you have no real world experience with solar PV. And just for clarity - solar power is now officially the cheapest way to make electricity. www.carbonbrief.org/solar-is-now-cheapest-electricity-in-history-confirms-iea Perhaps look in the mirror if you want to see the person who's "on something".

[@russiannpcbot6408]

@@antontaylor4530 Cheapest with massive subsidies. It's not reliable enough for most Americans. They don't provide enough electricity for day and night use for an American family. I have a large family in a 5 bedroom house. It gets very hot in the Summer and very cold in the Winter. Summer is frequently upwards of 38 C while Winter can get to -18. We use 2700 watts just for air-conditioning. Solar cannot meet our household needs. It can't for most Americans. Typically a coal or natural gas plant has to stay throttling manage dips in grid capacity for solar here. That negates much of any real emissions savings or total grid cost. Solar energy analysis typically doesn't include that necessary expense when calculating the cost of solar energy.

[@ronnyvbk]

There is a belgian company ilumen selling the PID box that reverses the degradation process, it has to stay in the circuit and regularly applies some reverse voltage on the cells to refresh them to factory state and avoids the efficiency drop.

[@creator8101]

15:18 wow that is the smoothest transition to sponsor I've ever seen

[@nobodyisn0tdead]

@dustybroom16 Last time I checked, smoothest didn't mean unexpected... A transition can be smooth and predictable.

[@csanton3946]

Polymatter is much smoother, that dude always caught me by surprise

[@daalhead1098]

"The problem solving website that teaches you to think like an engineer" - oh man, great! I really want to get a buzz out of writing a risk analysis of breathing

[@googiegress7459]

A risk analysis of risk analyses will really shut them up though

[@1SmokedTurkey1]

Think like an engineer= develop anxiety and overthink everything. Not recommended.

[@bernardwatts5339]

Risk analysis on breathing. Have you ever worn a mask in a dusty environment?

[@xiro6]

I hope Engineers know a loss from 20% to 18% is not a 10% loss. 01:00

[@PersonalTrainerLamar]

@@xiro6 Not an engineer (just a thinker), but I'm thinking that would be a 2% loss... But I also completely understood what he was getting at, and isn't THAT what truly matters in our interactions with one another (not nitpicking innocuous malaprop or semantic paraphasia)?

[@Dr_Larken]

As I collect the comments I notice the listener noting that to him realize that was also the best transition into the sponsor! It actually maintained my attention long enough to realize how awesome it was!

[@101personal]

Great video. I am subscribing to Brilliant thanks to your sharing of your learning progress needed to make this video. Thanks again

[@uss_04]

Feels like we’re going to have a major reckoning when PV panels have to be recycled. Electrification is great but there are a lot of intermediate steps to take place

[@FloryJohann]

Don't have to worry for another 40 years or so. glass and crystalline and the frame can be recycled and the back coating may also find a way to be reused.

[@sladeoriginal]

reckoning already here. you wont hear the negative side of all the wasted materials, it heresy to speak against renewables.

[@sladeoriginal]

@@FloryJohann you make it sound so simple. solar panels have been helping fill landfills for the past 15 years. cheaper to make new.

[@motor2of7]

The same reckoning is coming for all the electric vehicle batteries

[@m2heavyindustries378]

@BRAVOZULU DWEST boathouse Nice boat boomer, why don't you go and complain about your exwife on a fucking gold course

[@KemoTherapy69]

Answer: night bad, day good

[@spartendeath]

Well something has to be bad for another to be identified as good.

[@Marahute0]

You replied with a snarky comment without even watching the video. That makes you seem less smart, not more smart.

[@omarakhtar3075]

Actually, vampires and other nocturnal species think night good, day bad. It's a matter of perspective my friend

[@satelliteprime]

@@Marahute0 It was a joke. A simple silly joke, you walking humor deficiency. You seem to be having either a very bad day or are very insecure, but I do hope your day improves if it's the former. Hopefully if it does you'll stop policing comment sections for inaccuracies or lighthearted humor like an anemic, constipated killjoy.

[@gnomsrepnay]

@@satelliteprime the comment isn't the answer though...

[@jazmynkizzar4713]

Thank you so much for citing where you got your information from!

[@dieselhead24]

The smoothest and most seamless transition into a sales plug I have ever witnessed. Simply ... BRILLIANT

[@seanajacobs]

Really well done. I don’t comment much but since I have a masters in electrical engineering specializing in high efficiency solar cells, I really wanted to say nice work! Next step talk about tandem cells and see how they can push the efficiency limits to the 40% range (expensive - only for space or concentrator purposes). Also it would nice to mention that there is NO theoretical lifespan for photovoltaic cells. Unless physically damaged they’ll last forever! So also a big area of research is in better encapsulation so no moisture get in which is the typical failure mechanism.

[@dorothymadden7523]

Does this mean that the existing solar PV is not worth getting until the issues addressed in the video have been addressed?? They don't seem to be very efficient at all.

[@realGBx64]

But in the end chaos reigns supreme. The enthropy of a closed system always increases in time. Nothing lasts forever.

[@seanajacobs]

Dorothy Madden no. Solar PV is quite good currently. It is exponentially reaching the LIMIT of efficiency. This means there won’t be massive gains anymore unless somebody can break physics (or discover new physics :) ) This means that you shouldn’t skimp on cheap products though. As better workmanship and manufacturing will likely outlast any 20 year warranty they provide.

[@realGBx64]

@@seanajacobs sorry to be pedantic but you literally can't grow exponentially towards a limit. Exponential growth is towards infinity :P

[@seanajacobs]

You’re right. The term I was looking for was logistic growth. As it’s approaching an upper bound as an inverse exponential rate. Thanks for making me find the right term. I had forgotten it.

[@ludwigagawin]

I used to work at Sunpower, these brings back memories. I work In manufacturing so I understand everything you said. I still remember every step how we manufacture our solar cells. And how to break the 30% efficiency barrier? They already know what's the problem, unfortunately there is no solution yet.

[@ndvorsky]

No "yet" about it. The maximum theoretical efficiency is around 29%-27% depending on which limits you choose to measure by. We will never exceed this with single junction silicon solar cells.

[@knightofcydonia1192]

Quantum Dot film. Look it up. It's on the way already, and could allow 35%. Question for you though, if a person works at Sunpower are they able to buy / purchase a Sunpower panel without giving a home address you plan to install them on? Because Sunpower panels aren't up for purchase directly by consumers unless you supply them a home address. I have pleaded with them to sell me some as I live in an apartment, but they simply tell me no because they only sell them to home owners. :|

[@markchidester6239]

Still, loosing 70 percent of free doesn't cost much other than space needed to store it.

[@johnduff-tytler3548]

The brilliance of your knowledge being passed down to us , is astounding and beyond being one.s capacity.

[@nharlow_4303]

I cannot get over how smooth that sponsor transition was. (Seriously, though, I'm actually considering trying Brilliant.)

[@majapahitsumatra5771]

I've to say this is the best video, in terms of explaining science and keeping it interesting, many other KZbin science videos either take concepts too fast with little details or make it boringly long, like a class.

[@guffaw1711]

Wow, I didn't know how similar both in principal function and in design leafs and solar cell are, up until I saw this video! There's so many science channels that tell you the same things over and over again, not adding anything new. But Real Engineering is an exception. I've come to the conclusion that engineers make the best science educators. Other channels like Applied Science or Tech Ingredients are also much more in-depth than your average science channel on KZbin that are run by scientists that have become journalists.

[@adihus67]

Very nice and clear explanation. Thanks a lot. God bless you.

[@danyilkovalov6453]

Thank you so much. I write bacalour work about solar panels,and your video helped me to understend and also aknowledg some new about them.

[@ghaatakhb]

Being a solar engineer myself i can vouch on the efficiency of this video. Beautifully done ! Btw there is also LeTID which is a growing concern in PERC cells due to hydrogen passivation. Maybe you could do an immersive video like this on it sometime.

[@Broxine]

Hardik Bhatt could you elaborate a little about letid in perc?

[@ghaatakhb]

@@Broxine Where LID is a consequence of formation of Boron Oxygen complexes LeTID has been observed as a consequence of (to put it simply) too much hydrogen content in the form of rear side passivation. With increased temperature and illumination on field the hydrogen atoms are freed into the Si-Bulk this is just another way of saying that the free electrons available are reduced by the presence of extra hydrogen. This effect accelerates and is visible when perc modules are subjected to high irradiation and temperature. Ask a manufacturer about it..and they will either have no clue or will simply deny this. I don't know why. With more than 10% of the global industry immersed in PERC technology this is something that should have been studied extensively and the least they can do is educate the public about it.

[@ghaatakhb]

@@Broxine the losses due to LeTID have been observed to go all the way upto 10%

[@Broxine]

Hardik Bhatt wow thanks for the explanation. So is it better in your opinion to avoid buying perc modules?

[@ghaatakhb]

@@Broxine that is not an option since the industry is slowing moving towards this technology. The best thing to do would be to have a strong legal contract which ensures that you're covered on linear warranty in the event that the degradation is very high

[@NotAverageAfro]

Linus would like to know where you get your segways from.

[@c.j.hatton]

he would haha

[@snorttroll4379]

prolly not lttt store

[@DeathBringer769]

The word is segue. "Segway" is just a type of brand of those auto-balancing "scooter" type things, lol.

[@NotAverageAfro]

@@DeathBringer769 Cheers

[@richardmarkham8369]

Great video. I learned a lot. No mention of the different crystal types in solar panels?

[@bob_greene]

this is a good video to explain transistor construction, too (n-type & p-type topic)