Does your smartphone have that annoying habit of running out of juice when you need it the most and when, of course, there’s no power source anywhere near?

We’ve seen all sorts of contraptions designed to charge your phone on the go, by capturing either solar power or the bike pedal-generated energy. But what do you do if its’ raining and you’re on foot? The SolePower shoe insole takes care of that problem.

SolePower Shoe Insole Harvests Walking Energy

The insole prototype is removable, so it can be used with any pair of shoes and is able to charge portable electronics while you walk.

Developed by Pittsburgh startup SolePower, the device consists of two parts: the insole and the battery. The insole is placed in the user’s shoe, while the battery is strapped to the ankle or the top of the shoe. A wire snakes out of the insole through the laces and is plugged into the battery.  As you walk around, the generated energy is turned into electrical power that charges your battery.

The battery can be used with various portable devices such as phones, GPS units, radios. Manufacturers say a 2.5 to 5 mile walk will provide the battery with enough juice to recharge an iPhone. Given that the battery is fully detachable, users will not have to remove the entire insole in order to power up their devices.

The entire device was designed to be completely weather-resistant and waterproof. During simulated tests, it was rated to last 100 million steps and it can withstand up to 350lb of weight. The smallest insole size can fit a U.S. size 8 for women.

SolePower’s project is currently on Kickstarter, where it is halfway through its $50,000 goal, with over 30 days left to go. Backers who pledge at least $100 will receive an insole device and a bonus T-shirt.

This gadget would be ideal for people who go hiking and camping very often or those who walk long distances every day and would like to use the opportunity to do something else besides losing those extra pounds. Most importantly, the SolePower shoe insole would be very useful in developing nations where access to electricity is limited and waling is the main means of transportation.

[Image via Gizmag]