Solar backup systems have been used for nearly thirty years by businesses and homeowners to supply uninterrupted power during black-outs or whenever necessary. Backup systems work by using batteries to store energy harnessed from sunlight via solar panels. When grid sourced power fails, the solar power stored in the batteries kicks into action and provides a smooth transition and uninterrupted flow of energy to your appliances, lights, and electrical systems.

Most solar systems are connected to the utility grid, drawing power from the grid when needed and sending power back when there is excess available. Grid-tied solar systems are designed to shut down in the event of a power outage. This is why backup solar systems are often utilized to guarantee nonstop power to the home. A solar PV panel collects DC power and sends it to a battery bank by way of a charge controller. The charge controller regulates the level of charge of the batteries in order to prevent overcharging or total depletion.

Backup systems also require a special inverter to convert the DC power into AC to run your home’s electrical systems. For grid-tied systems, inverters are programmed to shut off in a power outage. That is what makes a backup system inverter special; it will continue running regardless of the utility grid’s output.

Backup solar systems are designed to store at least enough power to run your critical loads. Critical load is the power necessary to run essential electrical systems in your home such as heating systems, computers, well pumps, refrigerator, and lighting. A solar backup system which can satisfy critical loads will likely have three or more batteries in its bank. These are connected to the AC panel in your home and set up by your solar installer to switch on automatically whenever needed!