On a good sunny day, a 40-watt solar panel can generate about 40 watts per hour. if you have 7 hours of sunlight that means you can have roughly 238 watts available to power smaller items. Yes, 7 x 40 is 280 but you need to factor in about 15% for energy loss. This amount of energy is what. It can but you may be waiting up to a week or more before the battery gets recharged. The amount of amps produced by this size of solar panel is about 2 to 2 1/2 per hour. That is about 1/10th. While there are different size batteries, you do need to find the right one for your solar panel. If you get 57 hours of sunlight you are looking at generating roughly 200 to 280 watts of power. In full sun, the number of amps you will get each hour will be between 2 and 2 1/2. If the sun does not stay out for long periods, that production will go down. If the sun stays out for about 8. Two main factors in this process will determine the length of recharging time. One factor is the sun. If you get a lot of it, for example, in the middle of the summer where the sun stays.
