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Many utility companies are starting to use renewable energy such as wind, solar and geothermal. That means that for some of us, the energy coming from our walls is renewable. But for most of us, the electricity we get from our outlets to charge our gadgets is still based on fossil fuels. Luckily, there is a growing number of ways we can charge our gadgets without plugging in to the wall at all. Here are a few ideas:
Wind
There are several great options out there for harvesting wind power that are more practical than putting a turbine on your roof. The Hymini personal wind charger is one of these options. Small and light, it can hook to your bike and gather wind power while you ride, or just hang out your window to catch a strong breeze. A similar device is the Mini Kin. This device has a suction cup to make it easer to set up to capture wind power.
Solar
Solar chargers are getting cheaper but they're still on the expensive side. They are a great way to charge smaller gadgets and there are even options out there strong enough to power laptops.
For gadgets, solar power is probably the most widely available option for charging up off-grid. From backpacks and fold-up chargers, all the way to clothes, you have your options stretched wide before you.
Rather than list them all, we'll provide some tips for shopping. First, look to make sure the charger can generate enough watts to adequately feed your gadget. If your device uses a lot of juice, a weaker charger might not hack it. Second, look at how long it takes to charge up. If you don't live in a sunny area, it might take days of sun bathing before you have enough juice to charge your gadget. And finally, price shop. Some solar chargers can be really expensive, but they don't have to be. Comparison shop to make sure you're getting a good deal.
Kinetic
Most kinetic charging devices are still in the development stage. Ideas in the works, though, include the iYo-Yo can charge your iPhone by, you guessed it, yo-yoing and you can dance up the battery power of your cell phone with a strap-on charger.
One of the reasons these kinds of devices aren't quite here yet is that they have a lower rate of efficiency when it comes to how much energy it can harvest with movement. It takes a lot of work for a little bit of energy, as shown by this hand-crank cell phone charger. So while powering a gym with those stationary bikes is a great idea, we're still a ways off from doing that on the consumer level.
Charging mobile devices without plugging into the wall is a technology that is already here, and luckily our options will only get better!
For more info on choosing a solar charger, check out this solar charger guide. And for more information on greening your gadgets, including charging them up, check out our How to Go Green Guide for Gadgets.