Like your solar calculator, IllumiCharger runs on energy from interior light.

The promise of wireless electricity transmission has occupied the minds of electrical engineers, physicists and inventors since electricity was discovered in the 1800s. From the time Nikola Tesla dreamed of transmitting enough electricity to power entire cities, until today, there have been numerous attempts at wireless electricity transmission -- although today's iterations are designed to transmit electricity across a room, rather than across town.

And while some of these new wireless electricity technologies have moved out of  product development and onto store shelves, they all have one thing in common:  the device that actually transmits the power must be connected to a power source. What if you could charge your gadgets with the ambient electrical energy in your apartment or office? Enter the IllumiCharger, a light-powered USB wall outlet.

Sound too good to be true? Well, this isn't exactly wireless electricity transfer like Tesla and others envisioned or developed. It's actually not technically wireless energy transfer as is normally understood. The IllumiCharger operates on the same principle as the solar calculators that have occupied classrooms, offices, and desk drawers for over 30 years:  it collects and stores energy from ambient interior lighting via small solar cells embedded in the device; providing what is essentially free charging power for MP3 players, mobile phones and any other personal electronic device with a USB port.

"I've always loved the idea behind classroom calculators that used this excess indoor light energy to power themselves," says IllumiCharger inventor Ryan Hess. "I actually remember the particular calculator I had as a student... it had a protective flip cover that I would always flip back and forth... peeking to the side each time to watch the screen turn on, then off, and so on. This was very entertaining to my mind, even as a child."

Hess says he thought up the idea while brainstorming the notion of using indoor light energy in ways that would be of use to the masses. "The Illumi-Charger's claim to fame will be that it serves so many people, gadgets, and uses with practically zero effort by the user," says Hess.

The IllumiCharger design will be featured at this year's Greener Gadgets conference in New York City on February 25 where it has been named a semi-finalist in the conference's design competition.

Hess says he has talked with a number of product developers and hopes to have the IllumiCharger and a handful of other products to market "within a year or so."

Follow Tim Hurst on twitter @ecopolitologist