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This is yet another entry in the venerable category of “designers congratulating each other for designing something that is either useless or completely impossible”
Solar chargers for phones have existed for quite some time now. I’ve got one, it’s mildly handy.
So, the product segment really does exist. This is not blatantly impossible. But it’s got three problems.
First.) The on/off switch appears to work by rotating the plug, since designers hate obvious physical controls.
This is not “intuitive”. This is the literal opposite: no product in the world turns on by rotating the AC socket, because you can’t pass UL certification with that design. This product could not be sold as designed.
Second.) The problem isn’t solar cell efficiency so much as the solar constant. The panel just wouldn’t get enough light, even if it was perfectly efficient. It is just too small.
Eyeballing it, I’d say the cell’s about 30mm in radius. 2*pi*r^2 = 5654mm^2 = 0.005654 metres square. That’s tiny.
Assume 1000 watts per square metre solar irradiance, times 0.005654 solar cell area, times .20 cell efficiency, and you get 1.308 watts.
But that’s pointing directly at the sun, and you’re meant to stick this to a window. So reduce the effective area by 30%, maybe. 0.9168 watts. An iPhone 5 draws five times that while charging.
That’s before you lose power to electrical resistance in the wires, and the voltage step-up converter, and battery charging losses.
They say it takes 5-8 hours to charge the 1000mAh internal battery, which seems to indicate it holds about 5 watt-hours, maybe. So, it’d take 5-8 hours to charge an iphone, or an hour if the internal battery was full. But…
Third.) The product photos show an Europlug. All solar chargers use DC output (with a barrel jack or a USB plug) because inverters are damnably inefficient, and running the output AC voltage through another AC to DC converter, the phone’s plugpack, throws away even more power, which this does not have to spare. It’s entirely possible that a line voltage plugpack would refuse to work at all when running off of this— a perfectly efficient inverter would only be able to source 5.4 milliamps at 240 volts, and plugpacks expect to be plugged into the wall, where they can suck down thousands of times as much current.
If this was a real product, which it ain’t, then it would really, really suck.