Move over, solar, there’s a new power source in town.

Most of us feel naked if we don’t have our cell phones, PDAs, laptops, mp3 players, and cameras. We can’t stand being without them for a second—even when they need to be charged.

Thanks to the Fraunhofer Institute for Integrated Circuits in Germany, those charge-up delays may be a thing of the past. Forget looking for a plug. A new power supply—our own body heat—could be all we need to keep our gear going. Give your portable devices some love from your warm hands and they’ll be charged and ready to go. As detailed in the Discovery article:

The technology has already been shown to work on a wireless sensor that could be used to constantly monitor a patient’s temperature and send the information to a nurse’s station. It could also be used to power a hearing aid or to supplement the battery power on larger electronic devices, such as a sports watch or a mobile phone.

And because the circuit essentially converts waste heat into energy, it could have applications outside the body. For example, it could be used to convert the heat from radiators, refrigerators, or air conditioning systems into energy that can be reused by a building.

How does it work? The difference between the body’s surface temperature and the surrounding environment is typically only a few degrees. According to electrical engineer Peter Spies, this can produce 250 millivolts. A typical electronic device needs one to two volts in order to operate, so a charge pump stores our body-heat millivolts until they build up enough potential energy to activate a transistor and provide power!

So, an ultra-efficient way to create energy, or another reason for us to sit on our butts?

Wife of the future: “Honey, will you please walk the dog?”
Husband of the future: “Can’t, babe, I’m storing energy!”

You decide.