Solar System Types: Grid-tied, Off-Grid, Hybrid

Grid-tied solar systems are the most common type due to their lower cost and reliability. The solar array sends electricity directly to your home’s main service panel, which is also connected to the utility power grid.

The grid provides a reliable power supply for when the solar is not producing enough energy, as well as a place to send excess energy during times of high production. Net metering, which is available in New York, sees the electricity sent to the grid stored as credits on your utility bill that can be used to cover future electrical costs.

Grid-tied solar systems are the most cost effective – requiring simpler installation and less equipment, particularly needing no expensive batteries. The downside is that, without batteries, the solar cannot be used to power your home during utility outages.

Off-Grid solar systems have no connection to the utility grid and are entirely self sufficient. The most common use for off-grid systems is for rural areas and remote cabins that are not serviced by the utility grid. Otherwise, these systems are for people who want complete independence from utility companies. No grid interaction means having power during utility outages as well as freedom from fees and rate changes.

Keeping a house powered without the grid requires a significant amount of battery storage. During the day, surplus electricity is used to charge the batteries which are used to power your home overnight. For a northern climate like New York, the system needs to be sized around winter energy demands as it is the time of year with the lowest amount of available sunlight.  The possibility of winter weather keeping solar production low for days at a time is one of the reasons many off grid systems have a second source of backup power such as a gas powered generator.

The overhead cost of off-grid systems is much higher than grid tied, as batteries are expensive – especially the amount required to power an entire household. Additionally, without a grid to fall back on, those living off grid have to be very conscious of their energy consumption and production – potentially adjusting their lifestyle around availability of energy.

Hybrid solar systems combine the benefits of grid tied and off grid solar by offering battery storage while still being connected to the utility grid. This offers some of the independence of an off-grid system, without the design and lifestyle restrictions that come from having no grid to fall back on.

Excess energy charges the batteries and can be used during periods of low production as well as during grid outages. However, unlike an off-grid system, the amount of storage to be installed is flexible. It can be tuned to match your personal budget and energy goals as there is no need to power the entire house, only the essential loads you want to run during outages. The grid can cover any demand not met by the batteries. On the flip side, if production exceeds battery capacity, net metering is still available, so no energy is wasted. 

Less batteries means there is less overhead cost for a hybrid system than an off-grid, though the amount of equipment and complex installation is still much more costly than a grid tied. The current push for electrification in New York, however, means there are special incentives available for grid-tied battery systems. To qualify you need to allow the grid to pull from your batteries during times of peak grid wide electrical use. As demand on the grid increases, these incentives are likely to increase.

Choosing a Solar System

A grid-tied system will always be the best financial choice. The lower equipment cost and simpler installation make for the lowest initial cost and greatest return on investment compared to the alternatives. In addition, the simplicity of the design makes for lower potential maintenance and repair charges during the life of the system. For this reason, a grid-tied system is the most attractive option for most customers, whether they are seeking to save on utility bills with solar, or trying to go green without breaking the bank.

Off-grid systems are largely impractical for the typical homeowner. A battery system large enough to supply the average household is very expensive, especially when you consider the need to work around the limited hours of sunlight during winter. For that reason, off-grid systems are best reserved for areas where the grid is not available.

Hybrid systems are a good choice for those who experience a lot of utility outages, or anyone who seeks increased energy independence. Flexible system design and the potential for utility incentives make these systems much more affordable than going fully off-grid. However, the initial cost and potential maintenance will be more than a grid-tied.

At the end of the day, the best way to decide which system is best for your home is to talk to a knowledgeable solar installer. They can walk you through the costs, benefits and potential designs for your specific location, budget, energy use and utility service so you can make your choice with confidence.