No Stupid Questions

A device, which is only used when it is really cloudy for photovoltaics has to be one of the dumbest ideas ever.

People always severely underestimate how little power solar panels actually produce. In optimal conditions they get around 1000 watt per square meter, but are only around 20% efficient. So that means 200 watt produced at the panel. Once you convert that into something useable and transport it to where you need it, you'll probably lose another 5 - 10%. And that's a square meter, that's more than you can comfortably carry. Think a flat panel of around 2 meters in length and 0.5 meters wide and lifting that above your head, pointed perfectly at the sun.

And the reality is, most solar panels even in permanent installations don't experience perfect conditions. They don't track the sun, so most of the time they aren't perfectly aligned to catch all that energy. They are most likely never aligned perfectly, or if they are just a few days out of the year for like an hour a day. The sun isn't always out, not just because you know night time, but also because of clouds and other weather or human related stuff. Lots of times there are shadows that prevent optimal workings. Dust and grime also plays a part. But another thing is temperature, solar panels are rated at around 20 degrees C. But when you put a black thing in full sun, you know it's going to get scorching hot. This also reduces the amount of energy you can usefully extract from the sunlight as well.

The annoying thing about solar panels is they aren't linear at all. It isn't like when conditions are 80% from optimal, they produce 80% of the power. No, usually it's more like 60%. And once you drop below 40% of optimal, you just produce basically zero. With a bit of effort this can be improved upon. For example I use microinverters which can regulate each panel individually, but even then it's not great. And that's with state of the art panels, which are very fragile, so they have a sturdy metal frame, a very tough plastic backing and a big ass layer of glass on top to protect them. If you get those more sturdy thin and light panels, you'll be lucky if they get 15% efficiency (most likely a lot less).

So putting solar on anything that isn't a permanent installation is usually pointless. It's way too hard to get those ideal conditions and the panels aren't very good to start with. If it's moving, it's hard to point at the sun all the time. Exceptions are maybe a small panel on the top of a campervans, which is probably the best case for a mobile installation and gets just a little bit of energy. But only if it doesn't disrupt the wind profile of the van, otherwise it probably costs more in gas to push it along at high speed than it ever delivers back in electricity. One of those small foldable panels can also be useful when hiking for example. You can carry it collapsed on your back and if you take a break, you can fold it out, point it at the sun and get some useful energy for a couple of hours while you get some rest. Putting it on when hiking would be pointless, as it would be bulky when folded out, usually not pointed at the sun and under cover of trees for example.

Maybe the technology will improve in the future, but for now any useful personal solar is very niche.

Get a wind powered hat instead

Probably because it would weigh 40 pounds and cost $1700. It would probably also suck, and break very easily.

And having any of that shit anywhere close to saltwater? Hell no. The electronics should be corroded within a week.

Edit: while we definitely have the technology to do this, we just don’t have the capability to mass produce them at a reasonable price or of any reasonable quality. Current technology and materials also come with a lot of really crappy limitations. Maybe something like this might get developed if a lot of people suddenly show interest in it, but aside from that happening, it could be a while.

Developing a product like this could take hundreds of millions of dollars and 10 years to get something like in the picture above.

why would you have a solar powered umbrella instead of a parasol? isn't the only difference one is used when no sun lol

also sound like a bad idea either way

Get/create a solar backpack with a powerbank instead. That way weight is less of a concern and you can charge it when the sun is actually out without looking like a weirdo 😅

Looks like this guy couldn't get financed to make something similar: https://www.homecrux.com/solarbrella-turns-beach-umbrella-charging-dock-phone/74666/

-- but my search did turn up alibaba results for similar stuff, so they probably just stole the idea from him.

Nitpick: You want a parasol or sunshade, not an umbrella. Umbrellas are for rain (latin origins aside). It is cloudy when it rains.

Is your plan to walk around with your umbrella up when it's bright and sunny, or to wait until it's overcast, dark, and rainy—hoping I charge something?"

Maybe a parasol would be a better idea?

It would get stolen real quick too, unfortunately. Also probably very fragile or very heavy, and would only be useful for a very specific time of the year only (during very hot summer). No clue how much output that would make though, but I'm gonna guess it's not going to be anywhere near useful.

I have had the same idea. Photovoltaic cells are sadly all quite stiff and/or fragile ...

Do you usually use an umbrella when it's sunny or would you do it just to charge the battery? I know it's a thing but only very rarely see people do that, probably not enough to have demand for something like this. Backpacks with solar panels exist but I think these are pretty hard to find too.

What exactly is the benefit of having an umbrella mounted solar panel over regular solar panels

Like I feel like that would be an obvious thing,

I would have NEVER thought of this...

How are there no personal versions for wandering around on a sunny day with portable shade that gets you a charged battery pack?

Oh my god! THATS what umbrella man was doing! Whew! Solved a huge conspiracy there!

.....wait, but that STILL proves he was a time traveler! Dammit!

Solar cells are crystalline and rigid. You wouldn't be able to fold the umbrella up and put it away. Also, as someone else pointed out, solar cells work best in sunlight... which you won't want an umbrella for.

Why not add a bluetooth speaker and some search lights, maybe a perfume dispenser and a toothpick holder. fucking genius.

Ecoflow makes a hat with panels that charge a battery pack.

There are foldable and flexible solar panels that go on a backpack. An umbrella would be kind of silly. What are you trying to do? How much power do you need?

Here is a 6.5 watt solar backpack though I robably wouldn't buy it. It shoud be able to charge a 40WH USB power bank in a day or so lying down facing the sun. You never get the full rated power from solar cells. It weighs about 3 lb per the mgfr page.

https://sidedeal.com/deals/outdoor-tech-mountaineer-solar-panel-backpack

I just have never felt a need for something like that. The power to weight ratio is too low compared to recharging batteries from a wall plug, unless you have to go for long periods (like weeks) without access to a wall plug AND you are able to park the solar panel in good sunlight all day. If you want to use it while walking around, power collected will be several times lower.

Solar is great for stationary installations or maybe on top of an RV, but portable is of very limited usefulness.

fragile.

You could put them on a fixed awning, but you generally don't want solar cells flopping around, being vibrated or moving at all if you can help it

I know this sub is called "nostupidquestions" but c'mon.