solar system produces more energy in the summer,As the electricity flows into your solar power electrical system, it is either used in your building. into useful energy that can be used in homes. There are two main types: solar thermal and photovoltaic, or PV. Solar thermal panels use the sun’s energy to heat water that can be used in washing and heating. PV panels use the photovoltaic effect to turn the sun’s energy directly into electricity, which can supplement or replace a building’s usual supply.