New Yorkers with dead phones may be lucky enough to find charging stations in public parks this summer, but until that infrastructure becomes as normal as pay phones once were, we may still have to rely on ourselves to remember to power up. Or we can walk around with shoes that do it for us.
A new startup called SolePower has come up with a shoe insert that creates power as you walk. How much power exactly? According to their Kickstarter page (which is raising $50,000 to bring the prototype into mass production), walking 2.5 to 5 miles could fully power an iPhone.
"Our device is embedded in the insole, right where the user’s heel goes," explains co-founder Matthew Stanton over email. "When the user’s heel impacts the ground, our device absorbs that force and uses it to spin a small electromagnetic generator. All in all, we are creating electricity the same way a crank flashlight or a wind turbine does, except with an extremely slimmed down profile." Stanton adds that many people assume the insert uses piezoelectricity—the method of generating energy from pressure, used in a train station in Tokyo to capture energy from the constant footsteps of commuters, for example), but he calls those materials "expensive and inefficient."
Power generated by the cut-to-fit insert is stored in a battery back, worn around the ankle on a strap or tied up to one’s shoe laces. The founders envision the product being used primarily by anyone really, but it could be particularly useful for hikers or those who find themselves at a situation like a conference where there’s lots of phone-using and walking around, but little time to stop and power up.
They also hope to figure out a way to make the technology cheap enough for users in the developing world, where cellphones are a lifeline but electricity can be unreliable. "For now we are going with the Toms shoe model of buy one, give one away," Stanton says. Microfinancing could be one option to allow people to invest in the technology, but even then, Stanton says they’d need to get the price point to a place where $5 loans could make a difference. (Currently Kickstarter backers have to pay $75 to get one, but that includes other goodies as well.)
"There are a lot of factors to consider and working with NGOs and perhaps local mobile providers is a must to make this product available in such a way that it is practical and impactful," Stanton adds. "We know that anything over $30 is not reasonable. We’re confident that we can get to a price that is practical for people and suitable for us."