When planning a home solar system, one of the first decisions is whether to include battery storage. A solar-only setup sends excess electricity to the grid, while adding a battery lets you store that energy for later use. This guide compares the two approaches and outlines other key system choices, such as inverter type, to help you understand what each configuration changes and what questions to ask before you commit.

At a glance: Solar with battery storage can increase self-consumption of your solar energy and may provide backup power during outages, but it adds cost and complexity. A solar-only system is simpler and less expensive upfront, but you rely on the grid when the sun isn’t shining. The right choice depends on your energy goals, local net metering rules, and whether you need backup power.

Solar Only vs. Solar Plus Storage: What Changes

According to the U.S. Department of Energy, solar energy is not always produced at the time energy is needed most. Peak power usage often occurs on summer afternoons and evenings, when solar generation is falling. Storage helps solar contribute to the electricity supply even when the sun isn’t shining by capturing excess generation and releasing it later. Without storage, any surplus electricity your panels produce is exported to the grid. With storage, you can hold onto that energy and use it when your household demand is high or when the panels are not producing.

The NYSERDA fact sheet (a New York State resource) notes that pairing solar and storage allows you to store electricity produced by your solar panels for future use, reducing energy costs and providing power to essential appliances during outages. The Queensland Government’s battery buyers guide (an Australian publication) explains that home batteries cannot operate without solar panels, and they store excess energy for later use, helping to balance energy expenses. While the programs and incentives described in these state and international guides may not apply everywhere, the technical principles are the same.

Storage is never 100% efficient, the DOE cautions; some energy is always lost in converting and retrieving it. Still, the flexibility of time-shifting your solar energy can be valuable, especially if your utility’s net metering compensation is low or if you want backup power. For a deeper look at how batteries work, see our Home Battery Storage overview.

When Storage Makes Sense

The DOE’s homeowner guide says storage allows you to save energy and use it later in the day, like when you turn the heat on at night or run the dishwasher after dinner, or even when the power goes out. If your electricity rates are higher during certain hours, storing solar energy for those periods can reduce your bill. The value of storage also depends on how your utility credits exported solar, so ask about it when comparing quotes. Because net metering policies vary by state and utility, check with your local electric provider before deciding. Our How Grid-Tied Solar Works article explains interconnection and net metering in more detail.

Backup Power: It’s Not Automatic

A common misconception is that solar panels alone will keep your lights on during a grid outage. The Queensland guide states that during a power outage, your solar panel system typically won’t work to power your home, even on a sunny day, for safety reasons. To have backup power, you need a battery system and an inverter that can operate independently of the grid. The DOE’s inverter basics explain that solar-plus-battery storage systems rely on advanced inverters to operate without any support from the grid in case of outages, if they are designed to do so. Some inverters are “grid-forming,” meaning they can start up a local grid on their own, a process known as black start.

Even with a battery, whole-home backup is not a given. The NYSERDA fact sheet notes that a battery storage system will continue to function during an outage, but it won’t power your entire home; critical functions like heat, refrigeration, and lighting will still operate. The amount of backup power you get depends on the battery’s capacity, the inverter’s capabilities, and which circuits are connected. If backup is a priority, discuss your needs with a qualified installer and review our Battery Backup guide and the article on Home Battery Backup: Essential Loads vs. Whole-Home Backup.

Inverter Choices: Single Inverter vs. Microinverters

Every solar system needs an inverter to convert the direct current (DC) electricity from panels into alternating current (AC) for your home. According to the DOE’s design basics, PV systems either have one inverter that converts the electricity generated by all of the modules, or microinverters that are attached to each individual module. A single inverter is generally less expensive and can be more easily cooled and serviced when needed. The microinverter allows for independent operation of each panel, which is useful if some modules might be shaded, for example.

The DOE’s inverter basics add that string inverters connect a set of panels to one inverter. Although cost-effective, this setup results in reduced power production on the string if any individual panel experiences issues, such as shading. Microinverters, placed on every panel, prevent shading or damage to one panel from affecting the others, but they can be more expensive. Both types of inverters often include monitoring functions that let you track system performance through a computer network or app. It is expected that inverters will need to be replaced at least once in the 25-year lifetime of a PV array, so factor that into long-term planning. For more on inverter types and their roles, visit our Home Inverters page and the article on Home Solar Inverter Types.

Net Metering and the Value of Storage

The DOE’s homeowner guide defines net metering as an arrangement between solar energy system owners and utilities in which the system owners are compensated for any solar power generation that is exported to the electricity grid. Whether your system qualifies for net metering payments depends on policies and practices in your state and electric utility. How exports are credited affects whether storing energy for later use improves your savings, so compare both options with your installer. Because rules change, always check current official sources and your utility’s rate structure. The PVWatts tool from the National Laboratory of the Rockies (formerly NREL) can estimate production for your location, but a custom estimate from a qualified installer is recommended.

Decision Table: Comparing Configurations

Configuration What It Changes Key Questions
Grid-tied solar only (no battery) Excess electricity is exported to the grid; no backup power during outages; lower upfront cost. What is my net metering rate? Do I need backup power? Can I add a battery later?
Solar plus battery (hybrid or AC-coupled) Stores excess solar for later use; can provide backup power if configured correctly; higher upfront cost. How much storage capacity do I need? Is my inverter compatible? What loads will the battery back up?
Single (string) inverter Lower equipment cost; reduced output if one panel is shaded or damaged; easier to service in one location. Is my roof partially shaded? Will I need to replace the inverter during the system’s life?
Microinverters Independent panel operation minimizes shading losses; higher equipment cost; more units to service. Will shading be an issue? Am I comfortable with more complex servicing over time?

All configurations require a site assessment by a licensed professional, and any work connected to home wiring or the grid must be done with permits and utility approval. For a broader look at how these choices affect your overall costs, see our Home Solar Costs and Decisions section and the Home Solar Financing article.

Frequently asked questions

Do I need a battery to go solar?

No. A grid-tied solar system works without a battery. According to the DOE’s homeowner guide, storage is an optional addition that lets you use solar energy when the panels aren’t producing. You can install solar now and add a battery later, though you may need an inverter upgrade. Check with a qualified installer about compatibility.

Will a battery power my whole house during an outage?

It depends on the battery’s capacity and how the system is configured. The NYSERDA fact sheet states that a battery storage system will keep critical functions like heat, refrigeration, and lighting running, but it won’t power your entire home. Whole-home backup requires a larger battery and an inverter designed for that purpose. Discuss your essential loads with your installer and see our Home Battery Backup article for more details.

Can I add a battery to an existing solar system?

Yes, in many cases. The DOE’s inverter basics note that solar can charge a battery directly over DC or after a conversion to AC. An AC-coupled battery can often be added to an existing system, but you may need to replace or add an inverter. Always work with a licensed professional who can evaluate your current equipment and local code requirements.

For more side-by-side comparisons of solar configurations, visit our System Comparisons page.

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