Folding Solar Panel Is Underpowered

If you hang out on certain kinds of sites, you can find huge-capacity USB drives and high-power yet tiny solar panels, all at shockingly low prices. Of course, the USB drives just think they are huge, and the solar panels don’t deliver the kind of power they claim. That seems to be the case with [Big Clive’s] latest folding solar panel purchase. The nice thing about the Internet is you can satisfy your urge to tear things open to see what’s inside of them vicariously instead of having to buy a lot of junk yourself. Thanks [Clive]!

The picture on the website didn’t match the actual product, which was the first sign, of course. The panel’s output in full sun was around 2.5 watts instead of the claimed 10 watts. He’s also seen sellers claim they are between 20 and 80-watt panels. But the interesting bits are when [Clive] decides to rip the panel into pieces and analyze the controller board.

The tiny circuit board uses a buck regulator chip to feed 5V to the attached USB port. There are hardly any other components: a Schottky diode, an inductor, two capacitors, an LED, and the LED’s resistor.

Maybe those little panels would work for a Game Boy. We’ve seen some simple buck regulators before, but this one may be the most minimal.

30 thoughts on “Folding Solar Panel Is Underpowered

  1. Ahh, yes. The infamous “eBay Watt”. If flashlight shopping, you will also encounter the “eBay Lumen”… The way some crooks inflate their item specs is just absurd! (999000000 lumen flashlights that run on one 18650… riiiight….)

    1. ^ this, these days there’s not a single LED, solar panel, battery, or power tool being sold that’s not making utterly ridiculous claims about performance, usually beyond the laws of physics never mind plain old sanity or credulity.

      Honestly it sucks because I’ll happily buy your cheap product that doesn’t perform quite as well as the one that costs 5x the price, but when you advertise massive lies it’s impossible to know whether it will work at all.

  2. And while we’re at it let me sell you (for an enormous price) an antenna the size of your pinkie nail whose bandwidth and gain violates any possible interpretation of the Chu-Harrington volumetric criterion, entirely based of course, on the priescent works of Nikola Tesla.

  3. He has a big problem. And he can’t normally take something apart without destroying it.
    500mA at 5V is perfectly enough to charge any USB device. In fact, it is the typical capacity offered by these ports.

        1. That’s another fun one they’re putting milliamp or milliwatt instead of just moving the decimal point makes it seem bigger than what it is right it’s a half amp then once it’s hooked up to a battery you get a fifth of an amp pendng on the charge state of the battery

  4. Look up the data sheet for NS6322, it is capable of 5V/2.4A
    If you connect a variable load directly to the PV array, you can directly measure the V-I curve.
    Or at least measure the open circuit voltage (which Clive estimated at 5.5V) and short circuit current (which Clive claims as 0.5A and the protect spec ’10W’ claims as 2.0A)
    As an engineer, I always like to see real measurements, not hearsay claims.

  5. I recently bought pair of 150×130 mm 5V solar panels and a small, USB powered, motorized turntable from amazon. The turntable said it used 5V at 0.5A and required 0.25W – yes, it said both! The solar panels are claimed to be good for 500 mA each. I got lucky. A single solar panel powers the turntable just fine.

    Now when the sun streams through my window, my mirrored mushroom spins and throws light beams everywhere like it’s 1978!

    Now I need to figure out what to do with the other solar panel…

  6. 20w? 80w? I’m calling for 10,000w solar panel from Aliexpress and eBay by the end of this year to go with $20 256TB SSD and bazillion mAh 2032 sized rechargeable lithium batteries.

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