Solar powered watches are a unique style of watch. They run off of sunlight, that is, they absorb natural sunlight and convert it into energy to power the gears of the watch.
These watches do require regular sunlight and you will have to refer to your user’s manual to find out exactly how much it will need. If it is stored in a dark place for too long (we often see this in watches that were not taken out of their box for several months), it may need to recharge for several hours to several days before it will function properly and accurately again. In some cases, if the power dies down too far, the capacitor inside the watch (it looks like a battery, but functions more like a rechargeable cell) may need to be replaced.
*Note: If you are attempting to recharge your watch, leave it in a sunny place, but not in direct, hot light, such as the dashboard of your car. If the watch gets too hot, it can damage the inner workings. It needs light, but without excessive or prolonged heat.