Grid connected or off grid?

When considering a solar installation there two distinct types of systems: grid connected and off grid. There are benefits and costs associated with each and understanding the differences can help you make the choice that best meets your needs.

Grid connected


A grid connected system doesn't have batteries, can transfer electricity to nearby neighbors when production is greater than consumption, and can take electricity from the grid when needed.

Off grid


An off grid system is completely self sufficient, storing energy in batteries for use at night and during periods when production is lower than consumption.

A grid connected system has fewer components than an off grid system and does not store any electricity on-site. With a solar installation connected to the electrical grid a home or business becomes both a consumer and a producer of electricity. Net metering is the term used by utilities to describe how they account for the balance between the amount of electricity used by the customer and the electricity exported to other nearby consumers. A grid connected system can be any size without the compromise of reliability compared to a facility that would be normally connected to the grid. System design is focused on producing the greatest total amount of electricity over the entire year.

An off grid system can be used to power anything from a small remote instrument to a home or larger facility. The size of an off grid system must be thoroughly planned to take into account the desired amount of consumption as well as the duration of usage required during the worst case production scenario (most of the time this would be a period of significant cloudy weather during the winter). System design is focused on providing the desired number of days of autonomy required by the project.

Factor Off grid On grid
Provides electricity when grid is down? Yes No
Transfers electricity to neighbors? No Yes
Is easily scalable if more production is desired? More costly Yes
Cost Higher Lower
Urban locations Less cost effective More cost effective
Rural locations Can become more cost effective Depends on access to grid