A grid-tied solar system, also called tied to grid or grid tie system, is a semi-autonomous electrical
generation or grid energy storage system which links to the mains to feed excess capacity back to the
local mains electrical grid. When insufficient electricity is generated, or the batteries are not fully
charged, electricity drawn from the mains grid can make up the shortfall.
Direct Current (DC) electricity is passed to an inverter which is grid tied. The inverter monitors the alternating current mains supply waveforms and generates electricity that is phase matched. The DC electrical system is attached to the mains via this mechanism. Because the local system is phase matched, electricity can be drawn from the mains in the situation of a generating shortfall or discharge in batteries.
There are a few key differences between the equipment needed for grid-tied, off-grid and hybrid solar
systems. Standard grid-tied solar systems rely on the following components:
» Grid-Tie Inverter (GTI) or Micro-Inverters
» Power Meter
Electricity has to be spent in real time. However, it can be temporarily stored as other forms of energy (e.g. chemical energy in batteries). Energy storage typically comes with significant losses. The electric power grid is in many ways also a battery, without the need for maintenance or replacements, and with much better efficiency rates. In other words, more electricity (and more money) goes to waste with conventional battery systems. The utility grid is a virtual battery