Citizen brand watches are another environmentally-friendly option, but instead they focus on solar power energy. While there are other designs on the market that use solar energy, many of those designs are considered bulky and unattractive. The Citizen brand has spent time crafting designs that are both environmentally-conscious and have a nice look. There are a couple of really unique factors about these watches. One thing is the atomic timekeeping, meaning that the watch syncs with the clocks in Germany or Colorado depending on the signal strength. Another interesting feature is that some models actually charge the battery based on the wearer’s skin temperature and the outside temperature. Features such as this make it no surprise that Citizen is a global leading watch manufacturer. Batteries aren’t your thing? If so, the Citizen Eco Drive is a great choice. Powered by any available light source, these fine Japanese watches were conceptualized in 1976. Now, more than 40 years later, they are available in an almost dizzying array of styles for men and women alike. Watches from Citizen’s Eco Drive collection may cost a touch more than models from some competitors, but these timepieces have an outstanding reputation for longevity, exceptional functionality, and style.