Solar electric power systems are essentially very simple.
You have a device which converts sunlight into electrical energy (a photovoltaic panel or 'solar panel') and this is used to charge up a battery.
The charge controller regulates the amperage and voltage that is delivered to the loads and any excess power is delivered to the battery system so the batteries maintain their state of charge without getting overcharged.
The battery allows you to collect energy when the sun is shining and store it until needed.
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