Solar + Storage

Pair solar electricity with a battery storage system for a more sustainable and resilient home

An increasing number of solar installers in Massachusetts are offering battery storage as an option to pair with residential solar electric systems, or as a retrofit to a previously installed system.

The most common use of batteries in a home is for backup power in the event of a utility power outage. When there is a utility grid outage, the battery storage system can isolate some or all of the household electricity needs (called loads) from the utility grid and continue to provide power to those loads. When utility grid power returns, the backed-up loads automatically reconnect to the grid. A home battery system can serve a similar purpose as a traditional fossil fuel generator, but unlike a traditional generator, there is no fuel to be purchased and stored during an outage.

If you have a solar electric system without a battery storage system installed, your solar panels will not be able to operate in the event of a power outage. Alternatively, if a battery system is installed without a solar array, it will be charged with electricity from the grid.

Combining a solar PV system with a battery storage system provides two main benefits:

Resilience

Solar panels can help recharge your battery to power your home’s critical loads through a power outage. Loads that are backed up by the battery system can range from small (lights, plug loads from electronics, small appliances) to large (refrigerator, well pump). Both the size of the loads tied to backup battery power, and the duration of time that the loads would be isolated from the grid will influence the size of the battery system installed.

Reduced greenhouse gas emissions

Solar panels charge your battery with clean electricity to power your home when the sun goes down or when the power goes out and maximize self-use of the electricity generated by your solar electric system.

If you do not or cannot have a solar electric system to pair with your battery storage system, consider joining a community solar farm or purchasing clean electricity to support clean energy on the grid.

Note: Some of the content featured in this article is derived from a Battery Storage Guide published by Solar United Neighbors.