Definition: A solar panel is a device that is used to absorb the sun's rays and convert them into electricity or heat. Description: A solar panel is a collection of solar (or photovoltaic) cells, which can be used to generate electricity through the photovoltaic effect. So, please note that the solar panel needs to be used with a power station, and the only way to use the solar panel is to put it under the sunlight. It can't store any electricity, nor can the solar panel be charged by a wall charger or other charging devices.