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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.
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.
Also known as a "flag"
Ha! That could be it too, but I had meant more like a wrap around the pole.
Those all sound like efficiency issues still. Covering any form of transportation with solar panels is primarily pointless because of how little power that would generate. Even if you covered every available inch with the most efficient panels invented, it would take over two weeks of sitting in full, direct sunlight to charge a solar-powered car, which you would drain in four hours of driving. As these panels are half as efficient as traditional panels, you could drive maybe ~~a~~ two minutes per hour you sit in full sun.
Where are you getting that two weeks number?
A car has up to 55 sq. ft. available to panel. A good solar panel gets maybe 20 W/sq. ft. efficiency. An electric car has around an 80 kWh battery. A day has roughly the equivalent of 5 hours of full sunlight.
Then you just multiply/divide everything together, and you get 14½ days.
If it takes 14 days to charge the battery, you just need to use it less then a 14th of its range per day and this all becomes very feasible, no? First link on google tells me high efficiency EVs output 6.4km per kwh. That's 30 km a day at 80kwh, nothing to scoff at in my opinion, although its probably less.
I also think it could become popular to lengthen the in between charging times with higher capacity batteries.
+1 for the use of wolfram
Then factor in the extra cost of the panels and connecting hardware. The ones mentioned in OP are supposed to be dirt cheap, but they're also half as efficient. The tradeoff cancels out the benefit.
Also, this won't help highway driving much. EVs have already solved city driving just fine. 100mi range will do, even without good charging stations outside your home (with caveats for apartment dwellers). Highway range is where we need improvement, but you can't ask people to just drive for 1/14th of the day there.
Gotta be useful during the zombie apocalypse though. No more raiding gas stations and broken down vehicles.
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.
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.