Grid Tied and Off-Grid Systems

What does it all mean?

GRID-TIED, GRID-INTERACTIVE ,GRID-TIE WITH BACKUP, OFF-GRID, HYBRID WIND/SOLAR Systems.

 GRID-TIED it means that (you are connected to and your power comes from the local power grid). You are buying your power from Central Public Service or from the local power companies.

A.      Grid-Tied Systems are connected to the local power grid, may also be generating their own power on site with renewable energy such as wind or solar. In this case, they may be using the solar or wind power only as a backup (GRID- TIED or grid connected but not grid- interactive). They are using grid power to recharge batteries after an outage but cannot send power back to the grid.

1.       Direct Grid-Tied Systems: This system is grid-tied system with renewable source of energy, a separate solar or/and wind charge controller and without batteries or backup capability.

2.       Grid-Tied Systems With Backup: This system is grid-tied system with renewable source of energy and there are batteries to store power, a separate solar and/or wind charge controller and/or a load controller on a micro system to make sure the batteries do not overcharge.

3.       Grid-Tied Systems With Backup With (Grid Interactive): This System have batteries to store power, a separate solar and/or wind charge controller and/or a load controller and may draw power from the grid or sell power back to the grid – Bi-directional power flow. This introduces (Net Metering). When the system have excess power being generated, The power system is selling the excess Kilowatt hours of electricity to the power company turning your meter backwards. 

B.      Off-Grid System: Off-grid is exactly that! Off-the- grid. Stand alone systems not connected to the grid. Usually off-grid installations are a product of necessity. Typically, the cost of bringing power to the site is very expensive and the alternative of generating power on site is necessary. With a large network of back roads traversing areas that have never had power lines installed, the availability of off-grid parcels of land is great. Off Grid systems require an inverter, batteries, Switchgear, monitoring, backup generator and a renewable power source. Off grid systems can be designed to run small camps or large homes.

C.      Hybrid Wind/Solar Systems: If more than one source of renewable energy is connected to the system, it is usually referred to as a HYBRID system. A hybrid system can be GRID INTERACTIVE or just GRID CONNECTED also it can be OFF-GRID system. Often, this type of system can be designed to accept all the sources of power with a common battery bank, inverter, controls, switch gear and battery monitoring.