The fire-side charger
What charges your phone while warming your soup? It is a BioLite’s CampStove. A portable stove for the outdoor gadgeteer, this nifty contraption uses the heat from a campfire to generate electricity by way of a thermoelectric generator, which then powers a fan to create airflow for improved combustion. Surplus electricity is sent to the USB port for use in charging electronic devices. Basically, plug in your phone, sit around burning wood and toasting marshmallows for a while and, after around two hours, your empty smartphone will be back to life. The BioLite CampStove might not be the most useful phone charger in the market, but it certainly works and you have to give its creators points for out-of-the-box thinking.
If you’re really keen on using fire to charge your phone, you may just want to consider going all out by using the sun You know that massive ball of burning gas at the centre of the solar system. Well, it turns out that it throws off astonishing 400 trillion watts on regular basis – roughly the amount of energy it will take to power 500,000 years of our current civilisation in a single second. And, yes, that includes charging phones. Of course, harnessing the sun’s rays is the tricky bit — which is why we can be thankful for the Solio Bolt Solar Charger + Battery Pack from the aptly-named Better Energy Systems. With its on-board battery and rotating solar panels, the Solio Bolt charges can charge USB-powered gadgets ranging from smartphone to MP3 player, e-reader and cameras. The maximum voltage is 5V; but there are a few more ingenious ways to recharge your batteries. On average, a smartphone will take around three hours to go from zero to full. Hey, who could dislike a gadget whose slogan tells us to just ‘Plug into the sun’?
A piece of fruit
What could be more appropriate than charging an iPhone with an actual apple (or more subversive than doing the same with a Samsung Galaxy)? Well, provided that you’ve got the right tools, a bit of time and, presumably, some fruit you’re less than keen to eat, it can be done. Essentially, what you’re building here is a circuit – like the ones you used to put together in science classes – using a regulation vegetable battery, created by sticking strips of zinc and copper into your fruit or root vegetable of choice. The electricity comes from the oxidation of zinc, with the organic matter serving as a conductive barrier, and the copper (in the form of a penny) completing the circuit. One fruit/vegetable will generate around half a volt of electricity, with stacks of alternating layers of vegetables, zinc and copper creating a lasagna-like battery series, each set adding to the total voltage. It might be a cool experiment, but it’s by far the least efficient phone charging method on this list (which is presumably why it hasn’t been commercialised). As science enthusiast, Theodore Gray performs an experiment. This is explained in his book, Mad Science 2: Experiments You Can Do At Home, But Still Probably Shouldn’t: “To charge an iPhone I had to rearrange the battery into six stacks of about 20 apple/penny slices each, with the six stacks connected in parallel to increase the current capacity. Even so it charged the phone for literally about one second, just long enough for it to come on and display the charging symbol.”
The wind turbine
Do you think the term iFan applies only to a person who camps outside the Apple Store the night before a new model iPhone is released? Think again. The iFan’s wind turbine approach to charging allows users to harness the ‘green’ power of the wind to energise their smartphones. Designed by ‘3D interior and exterior designer, Tjeerd Veenhoven uses a modified computer fan. The charging process takes around six hours – but enthusiastic (and fit) callers can speed it up by attaching their iFan to a bicycle.
Desperate smartphone users will get around 30 seconds of talk time per minute of cranking the BoostTurbine 2000, with the potential to crank all the way to a full charge. At 2000 mAh, you won’t be able to effectively charge laptops or tablets, but phones, MP3 players and other 5V personal electronics should all work effectively. Eton’s BoostTurbine 2000 is a purveyor of hand-cranked emergency devices – mainly flashlights, radios, and the sort-geared toward outdoor enthusiasts and survivalists.