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Published on October 27th, 2012 | by Nicholas Brown


Benefits of Using Solar Panels to Charge Small Devices

October 27th, 2012 by  

Apart from major appliances that you need to wash clothes, preserve food, and heat water, you may want to stay connected to the internet and keep your phones/tablet PC charged during power outages.

This article is primarily about long power outages caused by hurricanes that last days or even weeks (Hurricane Ivan left me without power for two weeks).

If you don’t want to spend much and just want to keep your phones charged, then you could do so at a lower cost by using a small solar setup (depending on how many devices you want to charge) instead of a typical gasoline-powered generator that would cost hundreds of dollars.

This is due to the fact that generators are normally larger than necessary (often over 1,000 watts), and therefore more expensive than necessary.

Before you buy a factory-prebuilt solar charger or set one up yourself, you should know the power consumption of the devices you need to sustain.

To sustain your wi-fi internet connection, you probably need at least 10 watts of power. As an example, the DSL modem that I have uses 6 watts, and the wi-fi router uses 4 watts.

Cell phones use a fraction of a watt, and tablet PCs use less than 3 watts. Cellphone chargers, however, draw about 5 watts (example: Blackberry 8320) if they are smartphones — generally, for less than an hour. The power consumption averages out to less than 1 watt.

Parts list (to sustain 1 smartphone and wi-fi internet connection only):

  • Inverter — all the inverters I have seen are over 100 watts, and those cost very little (less than $30).
  • 12 volt, 7 Ah deep-cycle lead-acid battery — this size has much better than average value ($20).
  • 20 watt solar panel with a charge controller if your area enjoys more than 10 hours of sunny weather daily ($70).

Total cost: $120.

Other notes:

The inverter will beep when the battery is low. Start conserving stringently as soon as it starts occasional beeping.

Fast beeping means that your time is up. Turn off the modem and router first so you can save the battery for the phone.

Cost of phone-only USB solar charger: less than $30.

Image: solar panel via Shutterstock

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About the Author

writes on CleanTechnica, Gas2, Kleef&Co, and Green Building Elements. He has a keen interest in physics-intensive topics such as electricity generation, refrigeration and air conditioning technology, energy storage, and geography. His website is: Kompulsa.com.

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