Solar Panels With Battery Storage

Why Add Battery Storage to a Solar System

A standard grid-tied solar system produces electricity only when the sun is shining, and it typically shuts off automatically during a power outage for safety reasons, even if the sun is out. Adding battery storage lets a home store excess solar production for use at night, during peak utility rate periods, or as backup power when the grid goes down. Battery storage turns a purely daytime, grid-dependent system into one that can offer year-round backup for some or all of a home’s electrical needs.

How Solar Battery Storage Works

During the day, solar panels typically produce more electricity than a home uses. In a system with battery storage, that excess power charges the battery instead of, or in addition to, being sent back to the grid. When solar production drops off, such as at night or during an outage, the home draws stored power from the battery. A hybrid inverter or separate battery inverter manages the flow of electricity between the panels, battery, home, and grid. Most residential batteries use lithium-ion chemistry, similar to batteries used in electric vehicles, and are designed to cycle daily for 10 years or more.

Solar Battery Storage Cost

Battery storage adds meaningfully to the cost of a solar installation. A single residential battery typically costs between $9,000 and $18,000 installed, depending on capacity, brand, and installation complexity; some homes add a second battery for greater backup capacity or whole-home coverage.

Battery costs may be partly offset by available tax credits or incentives, which can apply to battery storage even when added after the original solar installation, depending on current program rules. Confirm current eligibility with a tax professional or installer.

Backup Power: What to Expect During an Outage

How much of your home a battery can power during an outage depends on the battery’s capacity and how the system is configured. Some homeowners choose whole-home backup, where the battery can run most household circuits, while others choose a partial backup setup that powers only critical circuits, such as refrigeration, well pumps, medical equipment, and some lighting. Partial backup setups are generally less expensive since they require a smaller battery and simpler electrical panel work. Ask any contractor to estimate how many hours a fully charged battery can power your selected circuits under typical use.

Battery Types and Capacity Considerations

Residential batteries are rated by usable capacity, measured in kilowatt-hours (kWh), and by power output, measured in kilowatts (kW), which determines how many appliances the battery can run simultaneously. A larger capacity battery can power circuits for more hours, while higher output supports more demanding appliances running at once, such as an air conditioner or well pump. Battery lifespan varies by brand, so compare capacity, output, cycle life, and manufacturer’s warranty terms across proposals, not just price.

Hybrid, AC-Coupled, and DC-Coupled Battery Systems

Battery systems are generally configured one of two ways. In a DC-coupled system, the battery connects directly to the solar array before the inverter, which can be more efficient since power is converted from DC to AC only once. In an AC-coupled system, the battery has its own inverter and connects to the home’s AC electrical system, which is often simpler to add to an existing solar installation as a retrofit. A hybrid inverter combines solar and battery management in a single unit and is common in new installations designed with a battery from the start. Ask your contractor which configuration they’re proposing and why it fits your situation, especially if you’re adding a battery to panels installed by a different company.

Sizing a Battery for Your Home

Battery sizing depends on which circuits you want backed up and for how long. A contractor will typically review your must-run appliances, such as a refrigerator, well pump, medical equipment, or a portion of your HVAC system, and calculate their combined power draw to recommend a capacity in kilowatt-hours. Homes wanting only short-term, essential backup can often get by with a single battery, while homes wanting extended whole-home backup during multi-day outages may need two or more units paired with careful energy management, since even a large battery has a finite capacity and needs to be used efficiently to last through an extended outage.

Getting Solar-Plus-Battery Quotes

Battery storage pricing and configuration options vary significantly between contractors and equipment brands. Request up to 5 no-obligation quotes from independent solar contractors through HomeMatchr to compare battery options, backup capacity, and total project cost for your home. HomeMatchr is an advertising-supported service and may receive a referral fee when you connect with a provider.