The first USA solar-powered watch was developed by a talented American engineer out of a humble room in his house. Roger W. Riehl called his invention the Synchronar 2100, bringing it to market in the 1970s and going on to build a successful company around it. An appropriately space-age-looking thing, this innovative gadget brought together multiple fields and technologies for the first time and was the first step in the development and subsequent commercialization of the solar-powered watch.
The oil crisis in 1973 raised global awareness and interest in alternative sources of clean energy was raise again. Responded to the challenge by starting to develop watches driven by light. And in 1976, was created the world’s first Japanese light-powered watch by Citizen.