Grid Tie inverters are the heart of grid tie systems. Grid Tie inverters convert the DC power from your solar panels into AC power for your home, office or industry. They do not connect to batteries for electrical storage for use at a later time. They allow you to use the electricity that you produce while they are working and if you produce more electricity than you need they will sell the electricty back to the electric company. One thing to understand is that if the power goes off from your electric provider...Grid tie systems shut down. They do not work when your electricity is down!