Going Green is always good, as long as you find new sources of energy.
In Early school education, we were taught that a lemon with brass, copper plates can generate 0.3 volts. And more intuitively, we’ve seen DIY iPhone Solar charger, but Oranges charging Apple iPhones? Wooah.. needs alot of patience, after all How many Oranges does it take to charge an Apple?
It may not be as good as innovative as Phone that Charges from Coke, but sure is fun for the enthusiasts.