A candle and some water could keep your phone charged in an emergency

During a disaster, there are few options for charging the electronic devices that are so important to our modern lives. But now there's one more, courtesy of a company called Stower, and this one depends on very basic elements.It's kickstarting a 'Candle Charger' that exploits a nifty physics trick to charge any USB-powered device using just fire and water. That trick is the thermoelectric effect - a property of certain semiconductors. The effect turns a thermal gradient - when one part of the m