Three Ways to be Energy Independent
Battery systems are installed in one of three different configurations; Off Grid, Grid Interactive and Grid Independent.
Battery systems installed in the Off Grid configuration are for homeowners who do not have access to utility power. The battery system (when installed with a renewable energy source such as PV or wind) is the only source of electricity. The system is required to meet all the electrical loads of the home and provide power to the homeowner day and night, 365 days a year.
Battery systems installed in the Grid Interactive configuration are for homeowners who have utility power and want seamless backup power for when the grid goes down. In this configuration, the utility is the primary source of power and the batteries are used for backup. For times when the grid becomes unstable or no longer provides power, the battery system automatically steps in, continuing the electrical service to your home. Homeowners who have grid interactive battery backup systems usually only find out about blackouts when they notice their neighbor’s lights are out.
Battery systems installed in the Grid Independent configuration are for homeowners who want to use the battery system as the primary source of power and use the utility power as the backup. In this configuration the battery system acts as the primary source of power. When the battery system runs low on power, it automatically switches over to the utility to provide power. Using the utility as a backup gives the added security of always having power, even during extended periods of low sunlight (extended rain) where the PV system does not generate the normal amount of energy. An added feature of the Grid Independent configuration is since you are not operating your PV system in parallel with the electric utility, no interconnection agreement for your PV system is required. This can be especially attractive for homeowners who are having a difficult time getting an interconnection agreement approved by the local utility.