Hot Espresso Can Recharge You and Your Phone
If in the morning you wake up and realize that during the night your Smartphone’s battery ran out and you're away from the normal charger, the remedy is to give it a good coffee, provided it is hot. It works with the same principle invented in 1816 by the Scotsman Robert Stirling. He invented a device to exploit thermal efficiency, which he called a heat economiser and he further exploited the patent to build a hot air engine incorporating such a device. With this same principle of Stirling's, the modern "Puck One" disk draws energy from heat and transfers it via a USB cable to the phone battery. The first working prototype of the new device was developed by an American business, Epiphany Labs. It is designed to produce a maximum power of 5 watts, the same as a standard mobile phone charger.