Portuguese Prepper
Portable Solar Panels: How to charge your phone from the sun
If the grid is down for more than 3 days, your power bank will die. To maintain communication, you need a way to harvest energy from the sun.
Warning: Do not buy “Solar Power Banks” (batteries with a tiny solar panel on the back). The surface area is too small; they take 40+ hours to charge.
Instead, you need a dedicated Foldable Solar Panel (15W to 30W) that spreads out to capture maximum sunlight and folds down to the size of a magazine.
You need ~20 Watts to charge a phone at full speed.
Direct sun is required; they do not work well through windows.
Best practice: Charge a battery bank, NOT your phone directly.
The Community Favorite: BigBlue 28W
The BigBlue 28W is widely considered the best value in the survival market. Why? Because it includes a built-in Ammeter (digital display).
Solar charging is finicky. Without a display, you never know if your angle is correct. The BigBlue tells you exactly how many amps are flowing, so you can adjust the position to get maximum speed. It is rugged, waterproof (ETFE coating), and has reliable USB ports.
The Premium Brand: Anker 21W
The Anker PowerPort Solar is lighter and slightly more compact than the BigBlue, but it lacks the digital display.
It features Anker’s “PowerIQ” technology, which handles the “restart issue” well (if a cloud passes over, some panels stop charging entirely; Anker resumes charging automatically). It is a solid choice if weight is your primary concern.
Which panel belongs in your bag?
The “Buffer Battery” Rule
Solar output fluctuates constantly with clouds. Phones hate this and may stop charging to protect themselves.
The Pro Move: Use the solar panel to charge a “dumb” battery bank (like the Nitecore NB10000), and then use that smooth battery power to charge your phone later.
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