this post was submitted on 05 Dec 2023
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This has its own applications but I can't say I've ever heard anyone complain about thickness of solar panels. Efficiency, power generated, etc. Sure.
I don't think it's so much about thickness, but being super thin presumably means it requires less of a manufacturing process and also less raw materials. Could bring costs down on panels and make them more financially viable for projects.
On top of that, could make them viable for other surfaces that might not have been a good fit for them with current tech
Indeed, 44 lbs for an 8kw installation is very light.
For most users, I'd guess that unit area is more important. But for satellites, I suppose that as long as they can unfold, space isn't really an issue. You've got all of outer space to spread out into. But weight determines a lot of the cost of putting the thing up in space, so you'd like that to be low.
If they're cheap enough, you can just slap them on any available surface that gets a marginal amount of sunlight. Doubly so if they're flexible.
If you can print them on textiles they can literally be everywhere.
Weight does play a huge role for satellites and to be honest I have very little knowledge of solar panels they use. However since solar sail is a thing, I'd argue surface is indeed a factor with satellites. But perhaps they managed to get some use there. There might be even other use cases I just didn't think about. My original comment was mostly pointing out that thickness was rarely as big of an issue as it was efficiency.
For anything other than house roof solar price per kw is going to be the deciding factor. Rural land is very cheap compared to solar panels - we're talking about a 100:1 cost ratio.
Also I can't imagine you'd want to add too much extra weight to a skyscraper
Use cases increase if they are thin. Instead of limited to rooftops. For example, take a look at what Aptera is doing.
Burning investor money on a DOA meme product just like Lightyear One did?
Ooof
Clearly you've never ~~owned an air fryer~~ wanted a solar powered car. Or imagine shipping containers covered in these powering the trucks that haul them! Or trains! Even boats. Basically any kind of self powered transit, especially ones with greater surface area.
Second edit: Another idea! Clingfilm solar panels for windows, or blinds and curtains that can power the lights!
Or wind turbines skinned in thin, light, flexible solar panels. You'd double dip on energy per square meter. You could have a solar farm on a stick that also makes wind energy.
If you dream of covering a vehicle with panels and have it driven by that power, I have to burst your bubble. That's not even nearly enough surface to generate enough power. Perhaps assist in trickle charging battery, sure. But we already have flexible panels, even self-adhesive ones. And again, their biggest downside is not their thickness but efficiency. There will never be a self-propelled vehicle. Just a nature of things.
As for window blinds, etc. There is already glass that lets enough light through and can generate electricity. Those are even worse when it comes to efficiency due to non-ideal angle, light passing through, etc.
"We already have technology that doesn't do those things well enough, so this new technology that won't see advancement ever has no chance of addressing these issues either."
Trickle charge is awesome. Trickle charge the semi during your 8 hour driving shift and then another 8 hours while the trucker is asleep. If that nets half a charge every other day, that's a charge and a half a week. It's not self powered like a perpetual motion device, those aren't real. But regenerative braking is a worthwhile addition to an electric truck. Why wouldn't solar paper or whatever we want to call it also be part of the solution?
More like, it would take 8 days of constant sun to have an hour of driving.
Currently. Technology gets better
No, there is literally only so much energy radiated by the sun in a certain area. The number of square feet of roof on a car is just too small to propel it, even with magic theoretical 100% efficient panels.
You do know cars don't have to move all the time right? If I was on a road trip and got stuck because of no juice for whatever reason, I would be able to camp wherever I am for a couple days and then have enough to move.
Your thinking is pretty small minded
This isn’t some theoretical thing I’m making up. It’s really basic math and physics you should have learned in high school. To do a trip of a few miles you would have to charge for a week. Here is a good explainer with demonstration cars that have been physically built, maybe that will help drive the point home.
As outlined elsewhere in this thread, you'd have to move the Earth closer to the sun for this to be feasible. You can only get so much solar power as it stands, and even 100% efficient panels would only go so far.
Nah. Even 1% power is better than 0% power
Not when it costs any amount of money to do so.
There are physical limits at play to how much power this can provide. No amount of technological improvement can break them.
Imagine the driver plugging in the truck during the 8 hours while they're asleep. That's an achievable goal.
Here's a video of a camper van with traditional solar panels on the roof using a slide-out awning technique.
https://youtu.be/Ev5C9gf0zFc?si=97piy-3mV9TIsRlu
You might say that's impractical for regular use. Sure, it is, but your previous argument was that is was impossible due to physics, which the video clearly shows isn't physically impossible, so we're already much closer to a reality. I'm not saying it could drive forever without stopping or be the only power source. That's silly. But if it reduces the need to charge from a grid by X% it can be a useful technology. Go on now and tell me how it could never ever work.
A camper van. Which has electrical use for things besides turning a motor. Yeah, that's useful, but it doesn't exactly help your case.
Under optimal conditions, the sun gives us 1000Wh per square meter. Let's say you have a 100% efficient solar panel. A semi truck trailer has a max of 42 sq meters on top of its trailer. So you get 42kWh out of this.
It takes about 280kWh to keep a semi truck at cruising speed on the highway. Thus, in this most optimal scenario, it would give you an additional 15%. Even this assumes there is no additional aerodynamic drag from the panels, mounting hardware, or wiring. It wouldn't take much to completely blow that 15% away.
If it's a cloudy day, all of it is now deadweight, and now hurts more than it helps. If you don't drive on the equator, its output drops and it now hurts more than it helps. If you have solar panels that actually exist that do around 20% efficiency instead of 100%, it now hurts more than it helps.
I guess we could move the Earth closer to the sun. Won't help our global warming problems, though.
It also turns the motor bro, did you watch it?
Of course it does. Doesn't mean it's a good idea.
Did you math?
You first said is was physically impossible. I've shown you it wasn't and predicted you'd move the goal post from possibility to practicality. And you did. Thanks for proving that you don't really care about whether it could even possibly work, but just that you wanna dunk on excitement and be right on the Internet. Have a good day.
I never said this.
"There are physical limits at play to how much power this can provide. No amount of technological improvement can break them."
Also, the fact it powers the motor for the camper AND all the appliances and such just proves the viability that much more, as the extra power draw is still supported by the camper's solar power system.
Yes, there are physical limits. It cannot provide enough power to justify having it only for the purposes of turning a motor. A camper van can justify it because it has lots of uses for electricity besides turning a motor, and as long as you're paying the cost anyway, might as well connect it to the battery charging circuit.
You started this conversation with:
All things that primarily turn a motor. None of these are feasible to be powered this way.
Your physics isn't terrible but you're making absurd leaps into nonsence with the rest, you also don't seem to have practical awareness of trucking logistics.
Here's a thought experiment, if sticking news paper to the outside of your truck was proven to give a 5% fuel cost reduction how long do you think it would take before you see a truck covered in news paper? Probably hours at most, truck drivers don't like stopping to piss because the extra fuel required to accelerate to highway speeds cuts into their margins so you can be damn sure that if there was an inexpensive way to reduce the cost of charging their truck everyone will be on that.
Also trunks have a lot of stuff beyond the motor, security and logging systems for example as well as various forms of climate control. Also being able to leave a vehicle idle and have it's fuel slowly increase instead of decrease / denature is a huge thing in a lot of situations.
If course is not going to make a truck that can drive a heavy load without recharging but if its only going to cost the same as a paint coating and can supply a slow trickle then it'll be a very popular product.
Even more so for things like agricultural machinery, leasure vehicles such as campers and boats, or anything with large gaps between uses.
So let's think about how a hypothetical electric truck would charge throughout the day. Driver makes a 20 minute stop and there's a 350kW charger available (about the max of what's out there for this sort of thing right now). They'll get 105kWh of charge out of that.
The top solar panels I can find at the moment are 540W and take up 2 sq meters each. So a 42 sq meter can have 21 panels for 11kW. That's the power they'd be rated for in direct sunlight on a bright day.
Even if we assume they have that direct sunlight for 12 hours straight (they won't, not even in equatorial regions), they'll get 136kWh out of that per day. Only a bit more than what they'd get out of a 20 minute stop.
US regulations require that a driver take a 30 minute break after 8 hours of consecutive driving. I also understand that this rule is broken all the time, but I don't feel the need to pander to exploitative and dangerous behaviors on the part of trucking companies.
Then we get to the cost. Those panels will be around $5000 for the set, and there are significant labor costs involved, too. Call it $10k/trailer to save a 20-30 minute stop each day that the driver will probably take, anyway.
There's also significant weight added, which reduces how much cargo they can carry. The factor you're talking about in getting the truck back up to highway speed just got worse. The panels ones noted in OP would be extremely lightweight, yes, but they also cut the power delivered in half.
None of this can happen until the industry electrifies. Current electric semi trucks are barely suitable, and there needs to be some improvements in battery tech before they can be.
This idea doesn't even look good on paper with unrealistic assumptions made in its favor. Put the solar panels at the charging stations, not the trucks.
Or better, forget about long haul trucking and replace it with electrified rail. Mount the solar panels on racks above the trains, not on the trains.
And this technology is ideal for going over rail, road, parking areas and all that sort of stuff so of course it's likely to end up used in those places.
It's also almost certainly going to be painted onto truck roofs, RVs, trailers, boat decks, fencing, marquees, and just about everything else. We'll certainly see rolls of it carried in pretty much all groups that go camping or work in off grid locations - take the roll, steak out two corners then unroll it onto a sunny bit of ground and suddenly you've got twenty square meters of PV charging your vehicles, phones, laptops, and tools. Life boats with power to run desalination equipment and satellite communications will save many lives.
At a low enough price point it's worth it just to maintain charge in an ICE's starter battery when left idle and to power monitoring systems, for electric trucks it's a no brainer - free fuel and extended range for the cost of a paint job? It doesn't matter how little range it adds or how slow the fuel trickes in it'll become ubiquitous pretty much over night.
So you did say that. But you just told me you didn't. You're confusing. I also showed you a motor powered this way yet you say it isn't feasible. So I really feel like I'm done with this conversation. Good day.
Not my fault if you don't understand the difference between "impossible" and "infeasible".
Also known as a "flag"
Ha! That could be it too, but I had meant more like a wrap around the pole.
First, the thickness factor plays into flexibility. Just imagine surfaces of every shape being covered in solar cells. Flexible panels could also be less prone to breakage.
Second, with "as rapid as printing a newspaper", this might be a major cost-reduction thing, even on top of the process needing less high-pure Si material.
This might make solar power generation more attractive even if the efficiency would be lower than other methods, because this would drive the ratio $/kw down.
Kind of like these? Flexible solar panels are not a problem. And no, being newspaper thin will never be stronger than mounted on rigid surface. If it bends it has a definite limit in number of times you can bend it.
As for "printing a newspaper" and rapid production, when I see it I'll believe it. At the moment it's nothing more than speculation as they themselves have not made it yet. Every manufacturing process starts slow and then speeds up as process is optimized. The problem is whether there is a financial incentive to start producing in the first place.
By "flexible" I did not imply "use it as a hinge". It was more like: "you can install it on a non-flat surface", e.g. by gluing it down. Now that surface would provide the needed overall stability. Imagine having you cars roof and engine hood being completely covered in solar cells - or basically be a solar cell. No, you would not be able to drive it as an EV with the amounts of power provided, but it could trickle charge a battery, or power a fan in hot weather so the interior will not be boiling when you return to your vehicle after a day at work.
We already have the panel type which is glued on. But I guess it remains to be seen whether there's a financial incentive to mass produce this.
Indeed. Price is the key issue.
Bulky, heavy, stiff, ....
Which would all be a valid concern if you had to carry them all the time or bend them. There are flexible solar panels which you can glue on roof of your boat or car though.