In grid-connected, on-grid or grid-tied systems, solar energy is used during the day by the system owner. At night, the owner draws on the previously established electricity grid. An addition benefit of the grid-tied system is that the solar system does not need to be sized to meet peak loads, overages can be drawn from the grid. In many cases, surplus energy generated during the day can be exported back to the grid. One limitation of this system is that Inverters will be switched off in case of grid failure.