Solar PV panels generate power from Solar Radiation. During cloudy conditions, there are less solar radiation and thus the Solar PV panels produce less electricity. During rainy conditions there are typically no solar radiation and then no Solar PV power. In these conditions where the Solar PV generation is less, the system can use battery and / or grid power to supply the shortfall of power supply from Solar. If connected to the Grid, Grid power can be used to re-charge the batteries under these conditions. Generators can also be used to recharge the batteries.