Solar watches: light charging, reserve and servicing
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A solar watch converts light into electricity and stores it in a specified rechargeable cell. Some models charge under indoor lighting, but charging speed changes substantially with illumination. Use the manual for the exact movement, also called the calibre.
Read the light and reserve figures correctly
Distinguish the time needed to restore operation from the time needed for a full charge, and note the lighting conditions used in the table. A stated power reserve assumes the product's particular functions and energy-saving behaviour.
A watch left covered by clothing or stored in darkness may receive very little useful light. Follow the maker's charging instructions and temperature limits rather than assuming intense heat is a safe way to speed charging.
Solar does not mean maintenance-free
Use the specified rechargeable cell and service procedure. An ordinary disposable replacement battery is not automatically suitable. Water resistance, seals and other parts of the watch still have their own servicing requirements.
If charging or reserve deteriorates, identify the exact model and symptoms for service. The solar drive describes the energy source, not a lifetime guarantee for the complete watch.