Solar absorption refers to the process by which solar energy is converted into heat. This occurs when sunlight, made up of photons, strikes a surface and causes the molecules in that material to absorb the energy from those photons. The absorbed energy can cause the molecules to become excited or vibrate at higher frequencies, resulting in an increase in temperature.
In the case of solar panels, this process is used to generate electricity by converting sunlight into direct current (DC) power through the use of semiconductor materials that absorb photons and create a flow of electrons. However, some of the absorbed energy is lost as heat due to the natural properties of these materials.
Overall, solar absorption refers to the ability of certain materials to take in sunlight and convert it into usable forms of energy such as heat or electricity.