Why don't we have a solar charging phone yet?

[ultimatebob]

You would have figured by now that some phone manufacturer would have made a phone with solar cells on the back of it for trickle charging the phone. I'd give bonus points if it was a fold out panel that created enough energy to charge the phone in 90 minutes.

Come on guys, green energy is sooo hot right now! Those Tesla driving urban hipsters would be lining up to buy one if it actually worked as promised.

 

[mikeymikec]

IMO it seems more sensible to make a portable solar panel which charges a mobile battery and one plugs their mobile devices into that to charge them.

 

[ultimatebob]

IMO it seems more sensible to make a portable solar panel which charges a mobile battery and one plugs their mobile devices into that to charge them.

Yeah, but that's yet another thing that you need to carry around in your pocket. It would be much handier if it was integrated into the phone.

I guess that one challenge would be to make the solar panel durable, since you just lost the ability to put a case on the phone.

 

[WelshBloke]

IMO it seems more sensible to make a portable solar panel which charges a mobile battery and one plugs their mobile devices into that to charge them.

I have one of these and it demonstrates why a panel built-in to the phone won't work.
The one I have finds out to be many times bigger that a phone. It's bigger than my phone when it's folded up!
Unfolded and in bright sunlight I'd estimate that it would take 6 or 7 hours to charge my phone if I don't use it.

I do use it when camping. I use it to charge a battery pack all day, then I use the battery pack to fast charge the phone when the sun has gone down.

 

[ultimatebob]

I have one of these and it demonstrates why a panel built-in to the phone won't work.
The one I have finds out to be many times bigger that a phone. It's bigger than my phone when it's folded up!
Unfolded and in bright sunlight I'd estimate that it would take 6 or 7 hours to charge my phone if I don't use it.

I do use it when camping. I use it to charge a battery pack all day, then I use the battery pack to fast charge the phone when the sun has gone down.

Yeah, I was kinda imagining a single panel on the back of the phone that folded out to something like a 4 panel array for "real" charging. I mean, solar cells are supposed to be more efficient now, right? If we could power a calculator with a tiny 1 inch solar panel in the 90's, you would think that you could charge a smartphone with an 8x8 inch fold out solar panel now.

 

[WelshBloke]

Yeah, I was kinda imagining a single panel on the back of the phone that folded out to something like a 4 panel array for "real" charging. I mean, solar cells are supposed to be more efficient now, right? If we could power a calculator with a tiny 1 inch solar panel in the 90's, you would think that you could charge a smartphone with an 8x8 inch fold out solar panel now.

This is my solar charger with my phone case for a size comparison.

 

[ultimatebob]

Yikes. How long does it take that solar panel array to charge the phone? I'm also curious what the efficiency on those panels are.

 

[WelshBloke]

Yikes. How long does it take that solar panel array to charge the phone? I'm also curious what the efficiency on those panels are.

It takes ages. In that using it to charge the phone is impractical. I use it to trickle charge a battery pack, that way I can plug it in in the morning and just leave it to it.

I do live in the UK so you might get a bit more out of it! (I've used it across Europe and I've had similar results though)

I'd say they are handy as stand alone things but you are definitely not going to want one built into your phone!

 

[SKORPI0]

Not on the phone itself, but something like this. From July 2016. Not sure if the tech has changed/improved.

Here's a selection of chargers from Amazon.

Amazon Best Sellers: Best Cell Phone Solar Chargers

Discover the best Cell Phone Solar Chargers in Best Sellers. Find the top 100 most popular items in Amazon Cell Phones & Accessories Best Sellers.

www.amazon.com

 

[HutchinsonJC]

If we could power a calculator with a tiny 1 inch solar panel in the 90's, you would think that you could charge a smartphone with an 8x8 inch fold out solar panel now.

The oldest calculators using solar also only had a very small & simple lcd display, that in the dark, you couldn't see. As a reference, the TI83 (not a solar calculator) had like a 6Mhz CPU.

With phones, we're talking about very large color displays (OLED) that bring their own light output, CPUs in the GHz of frequencies, bluetooth, wifi, cell modem, some few GBs of RAM, gps, gyroscopes, accelerometer, magnetometer, light sensor, pressure sensor, cameras, speakers, charge controller, temp sensors, etc.

It's a drastic difference in power requirement comparing a phone of today against a solar powered calculator of the 90s. A lot of these phones have a 4 to 4.8 amp hour battery and have considerable power save features to make the most out of that battery.

You're looking at about 15 watts per square foot of solar panel (12" x 12") assuming you have overhead sun and no clouds and efficient panels, which isn't much different than a lot of 2amp chargers can manage. If you want something half that size (12" x 6"), expect close to half the wattage.

 

[pete6032]

Yikes. How long does it take that solar panel array to charge the phone? I'm also curious what the efficiency on those panels are.

That's the answer to why we don't have solar phones. It doesn't provide nearly enough energy at this point. Perhaps one day our phones will consume less energy and panels will be more efficient.

 

[sdifox]

You would have figured by now that some phone manufacturer would have made a phone with solar cells on the back of it for trickle charging the phone. I'd give bonus points if it was a fold out panel that created enough energy to charge the phone in 90 minutes.

Come on guys, green energy is sooo hot right now! Those Tesla driving urban hipsters would be lining up to buy one if it actually worked as promised.

Err phone size panel is not going to charge the phone in 90min.

 

[KentState]

I don't get how this would work. Have to keep your phone, face down, in the sun and for an extended period of time. All while it heats up and thermal throttles to hell. If anything, offer a solar panel hat and shoulder pads since those are sunny side up.

 

[Red Squirrel]

It would be kind of impractical since unless you can make a screen that also acts as a solar panel it would need to be on the back, which is always covered by a case. Suppose a solar case could work if it had a way to plug into the USB but still have a pass through port so you can still plug it in too. The amount of energy you would get out of that surface area would be small though, wild guess, maybe 200mw.

It's best to keep any charging infrastructure/power generation separate from the phone. Separate power bank, retractable solar panel etc. You're always going to have a source of power with you or close by at some point during the day. Home charger, work charger, lot of public places have outlets now too etc. So for those times you don't then the other options can be brought with you separately.

When I go camping I tend to bring a larger solar power pack with me so I can power other stuff too so even out in the bush I would not really make use of a dedicated phone solar panel.

In normal circumstances I tend to just plug in my phone at my PC at home or at work. I find I don't get that good of a charge anymore, it barely lasts a day, so I just charge it whenever I can but it's also not so bad that I have to worry about the battery if I'm away from home. I think if I really stretched it I would get a bit over a day, I just don't like letting it go below 50%.