You may already know of the standard ways of charging your electronic gadgets like your iPhone – plugging your charger into the electric socket or the USB port of your computer, or using additional battery packs. But do you know of these alternative green ways to charge your gadgets? How viable are they as of the year 2012?

1) Solar

Solar-powered chargers for your phones are very common nowadays – you can see more than 4,000 results when you search in Amazon for “solar chargers”. For example, see the solar charger in the video below.

Assessment: Commercially available. It works, though efficiencies can still be improved.

2) Motion

Motion is another form of energy (kinetic energy) that can be converted into energy to charge your phone. For example, there are a number of hand crank generators in the market that you can use. However, a more convenient device is the nPower PEG, a tube-shaped device that acts as a back-up charger for your phone, which you can hold onto or put in your bag as you are moving around. This is useful for hikers, bikers or other even walkers.  (See video below.)

However, the nPower PEG does not seem to be in large-scale production – to order one of these things, you have to leave your name on the company’s website to reserve them.

Assessment: Commercially available.

3) Sound

It has been reported that some researchers in Korea are working on a technology to charge your gadgets using the power from the human voice. This might mean that in future, you could charge your mobile phone just by talking on it, though you might have to yell!

Other than the human voice, other types of sound (or some people may call it noise) can charge your mobile phones. The company Orange came up with a T-shirt called “Sound Charge” that uses sound for example from the music at a concert to charge your phone – this was tested at the Glastonbury Festival 2011 and described in the video below.

Assessment: Experimental stage. Available for niche applications.

4) Electromagnetic Waves in the Surroundings

An Economist article in 2010 mentioned this technology – basically you tap on the energy from electromagnetic waves (e.g. radio waves, WiFi) in the surroundings to charge your phone. In 2010, a company called RCA said that its Airnergy Charger can scavenge WiFi signals and convert them into battery power to charge your phone. However, there has not been any further word from them since then, and there have been comments that the power from WiFi is insignificantly low and that it would take an extremely long time (in terms of years) to charge your phone.

Assessment: Not viable. 


5) Onions and Fruits

Last but not least, some guys figured out how to charge your gadgets with an onion, an orange and even a durian. Unfortunately, this has been shown to be a hoax by Mythbusters in the video below! (So this doesn't count as Technology N0. 5)

Assessment: It’s a hoax!

These are the 4 alternative green technologies that could charge your iPhone or other electronic gadgets - 2 are commercially available (solar, motion), 1 is experimental or in niche applications (sound) and 1 is not viable (electromagnetic waves and WiFi). 

So go green and get yourself a solar charger or a motion charger today!