In the last three to four years, so-called ‘portable power banks’, a special storage case for electrical energy, rapidly conquered the market of mobile IT devices. Closely connected to this trend is Energy Harvesting. “This is a process by which energy is derived from surrounding, external sources such as solar power, light or heat,” explains physicist Dr. Oliver Lang, who founded the Sonnenrepublik together with marketing expert Andreas Guba in 2012. “It is our mission to make this form of environment-friendly energy available to more people around the world.”