Looks like Nokia is planning to make solar energy redundant by making cellphones that can be powered by radio waves. A prototype radio wave-powered cell phone is already in development at the Nokia Research Centre where it will be able to harvest 50 milliwatts of power which is enough to charge a switched off phone. If this technology works, then it could be used for a variety of appliances like MP3 players and other electrical devices that use around 100 milliwatts of power. Nokia plans to release the technology in three to five years probably as an add-on to solar powered cellphones.

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