Energy Storage

The Electricity produced from photovoltaic panels depend on the sunlight. During daytime, there is enough sunlight to keep the cells at maximum output, but during the night the electricity production will be much lower. Despite that the most electricity is consumed during the day, you still need it overnight too.

Unless you connect your photovoltaic panels to the power grid so you can reverse the energy consumption counter, you need to store the electricity produced during the day so it will be available overnight or in extremely cloudly days. With a solar system and a good battery, you can rely only on the electricity produced from the sun.