Solar-powered electronic watches can operate by harnessing the power from sunlight or even artificial lights. While some types of watches are fully powered by solar cells, others are partially powered. Such watches offer convenience because there is no need to replace batteries thereby also saving money. Besides, solar watches are also considered to be environment friendly.
The solar cells used in solar powered watches usually have a semi-conductor such as silicon. When light falls on silicon, it gets absorbed and the electrons start flowing inside the cells. Metal contacts attached in the solar cells harness the flow of these electrons and the electric current is stored in the form of charge in rechargeable battery.
The crystal has the solar panel behind it and the light is absorbed by the solar cells within this panel. The dial could be placed on the solar panel or on a layer. The power stored in the rechargeable battery is used for powering the watch during nighttime or when it doesn’t receive light.
Many solar-powered electronic watches are powered by lithium-ion batteries that can store enough power to run the watch for more than a year without getting exposed to light. Such a watch can enter a power-saving mode where the seconds hand is stopped until an exposure to light is received. However, not all types of solar-powered, lithium-ion-battery run watches have power-saving mode. However, they can still continue operating for at least 6 months.
The earlier solar electronic watches used to have external and visible solar cells, but in the new watches, the panels are internal and below the dial. The dial, however, is made from light-absorbing material. The cost of operation of such a watch is almost negligible because there is no need to replace the battery. The first time, solar watches came across the horizon was back in the 1980s. Initially, they were more popular among children, but gradually their benefits were experienced by everyone.