How Photovoltaic Systems Work

There are three basic types of solar energy systems available for residential and commercial use: (1) Grid-tie (2) Grid-tie with Backup and (3) Off-grid.

All use solar photovoltaic (PV) panels and are typically installed on the south facing roof of your structure. These panels power the system, producing DC (direct current) electricity when the sun is available. (If roof space is restricted or compromised, we can offer alternative solutions.)

Off-Grid Systems

Off-grid systems are typically employed where access to the electric utility grid is unavailable or when complete energy independence is desired.

For these systems, DC power is sent to a battery charge controller that charges the batteries and prevents over charging. DC power from the solar panels and batteries is routed to either DC circuits in the house or to an inverter that converts DC to AC (alternating current) electricity. The AC power is then diverted to the AC circuits in the house.


Batteries are the heart of the system. If the battery bank is not large enough to compensate for periods without sunshine, the house will not have electricity.

Fossil fuel generators or wind generators are typically used to generate emergency power if the battery bank becomes depleted.

Off-grid requires the most complex engineering and maintenance of the three major types of solar energy systems.

GreenLife Technologies can design a custom off-grid system for your needs.

To see our portfolio visit our projects page here.