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I want to see if I can charge my netbook with solar panels. With 16 smalls solar panels(they are from Westinghouse Turbo Rocket Solar Path Light with a 1.2v 150mAh a piece) the voltage and amps come out to be 19.2V and 2.4A. The power strip that came with the netbook has an output of 19V and 2.1A. Will charging it with a slightly higher volt and amp mess it up or anything? Thanks

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marked as duplicate by Ƭᴇcʜιᴇ007, Hennes, Mokubai, Shekhar, Breakthrough Sep 30 '13 at 1:56

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

Most of the answers to charger / volts / amps questions on the mess of duplicates this links to are crap. The one useful answer I've found is here - - basically, your input should have equal volts (lower fails safely-ish but erratically, higher risks damage) and equal or higher amps (lower risks damage) than the normal charger of your target device. Make sure your solar setup includes a DC regulator that enforces minimum and maximum volts and amps. And don't mix up amp hours (Ah) with amps (A), Ah is storage, A is current. – user568458 Jun 23 '15 at 21:54

You've made two mistakes. First, you blew the units. How did 150mAh turn into 2.4A? Where did the hours go? You're using the specifications for the battery as if they were the specs for the solar panel. The battery holds 150mAh. The solar cells most likely output more like 50mA.

Second, even if it did put out 150mA, you would need 256 cells to get 19.2V at 2.4A, not 16. You can connect two cells in series to raise the voltage or in parallel to raise the current, but you cannot do both without using more cells.

A solar panel that could charge your laptop the same way your power supply does would need to be about 4 square feet in size. A good rule of thumb -- a 20 watt solar panel can produce, in a typical day, enough power to run a small notebook for an hour and a half. A 40 watt solar panel can give you three hours. And so on.

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