Renewable energy
A 'Stirling' idea for charging your cell phone
The idea behind the Epiphany onE Puck is simple: use a Stirling engine powered by heat disparities (a hot or cold drink, a candle, ice, etc.) to fully charge your cell phone. Invented in the early 1800s, Stirling engines are far from new. However, with new materials and modern electronics they are now being put to use...