GRID TIED SYSTEMS
Grid-Tied systems use PV panels to generate DC power. The DC power goes to a grid interactive (grid-tied) inverter which converts the PV panel DC power to 240 volts AC power that is compatible with the power grid. The power from the PV panels goes (via the grid tie inverter) to supply the household power needs. If the PV system is generating more power than the house can use, the excess is sent out over the grid to supply others. If the house needs more power than the PV system can supply, then the extra is drawn from the grid as usual.
Grid tied systems only work when the grid is up. If the grid power goes out, the grid tie inverter is required to shut down immediately.
- Lowest initial cost (because there is no need for batteries and charge controller)
- Lowest ongoing maintenance cost (no batteries to maintain and replace)
- Simplest to install
- Most efficient (because there are losses associated with charging batteries)
- You can start small and add (with some limitations)
- During day time the solar array powers the load or shares the power with the grid thus minimizing the usage of electricity from the utility.
- At night time or the sun is on its minimum solar radiation, power is taken from the grid.
- In the event of power failure at night time, there will be no power produced.