Island Mode or Solar islanding is when a homes or business solar power system continues to generate electricity even though the grid is down. This scenario will not happen with a standard AC inverter as these require an AC connection to function, so were directly referring to the Powerful hybrid inverters here. Many people would consider this a good thing, as your home still has power from your solar panels or battery while everyone else has no power. However, things become dangerous when your solar panel system produces electricity and goes directly to the grid. This situation poses serious safety concerns to utility workers who are trying to fix the grid, as they could be injured if the grid is still "live". Anti-islanding means your inverter can detect loss of grid power and island your property as a safety feature. Creating a small “solar energy island” your solar panels and battery storage can keep operating your home without the risk of adding any unexpected electricity to the grid.  Once your inverter has put your property into "island mode", usually within 20 milliseconds of grid failure,  it will create you a new local UPS grid by combining earth and neutral together for safe operation. Island mode installations are complex and require advanced knowledge in electrical design and engineering.