Consider these alternatives, a solar PV system with:
- No batteries, grid connected system
- Some batteries, grid connected system
- Only batteries, no grid connection
System 1 is used to supplement your energy usage. In the event of a blackout or power outage, your solar system is by international standard requirements forced to shut down. Therefore, even if the outage occurs in the middle of the day during full sunlight hours- no power will be produced. If net-metering is allowed, this type of system provides a one for one credit on your monthly electricity statement.
System 2 is commonly referred to as a hybrid system and with the correct installation will act a UPS (uninterrupted power supply) in the event of a power outage. The PV system will charge up the batteries first and the excess production will supplement your household/ business energy needs.
System 3 is useful for areas where no grid exists. The energy produced will charge up the batteries which should allow for 3 days’ worth of energy needs and these batteries will feed the power requirements of the property.
It is however even more important to note that as you add batteries, you add cost and therefore the systems are ranked from the least expensive to the most expensive.