Home battery backup without solar: Is it worth it?

If you've lived through a multi-day power outage, you already know the cost of being unprepared. Spoiled food, no heat or AC, a sump pump that can't do its job—the list goes on. For many homeowners, a backup power system starts sounding very appealing after that experience. 

Generators have traditionally been the go-to option, but they’re noisy, require fossil fuel, and need regular maintenance. Battery backup systems offer a quieter, cleaner, lower-maintenance alternative—and what many people don’t realize is that you don’t need solar panels to install one.

A standalone home battery charges from your power outlets like any other appliance, then holds that charge until you need it. When the power goes out, it kicks in automatically. You can say goodbye to generator fumes, long extension cords, and trips to the gas station for fuel.

That said, a battery without solar has real limitations worth understanding before you commit. Here's what you need to know.

A home battery is a large rechargeable unit—typically wall-mounted in your garage or utility room—that stores electricity and releases it on demand. The most popular models on the market today include the Tesla Powerwall, Enphase IQ Battery, and FranklinWH aPower2.

Most residential batteries store between 10 and 20 kilowatt-hours (kWh) of electricity per unit. To give you a sense of scale: the average U.S. household uses about 29 kWh per day, according to the U.S. Energy Information Administration. That means a single battery won't keep your entire home up and running as usual, but it can power your essentials for one to four days.

When you install a battery without solar panels, it charges directly from the grid. Your utility sends power to your home the same way it always has; the battery just stores some of that power to have on standby for when the grid goes down. Think of it like a bigger version of a portable charging bank you might have for your cell phone.

In nearly every scenario, it’s going to make the most sense to pair a home battery with solar panels. But, there are a few legitimate reasons a homeowner might want a battery on its own.

Battery costs have dropped considerably in the last decade, but they’re still a big investment. The average home battery installation costs $15,228 for 13.5 kilowatt-hours (kWh) of storage—the amount most homes need to keep essential devices running during outages.

There’s good news: You may qualify for home storage incentives that can lower the price. While the federal investment tax credit (ITC) for batteries expired in 2025, some states and utilities offer additional rebates, tax credits, or programs—like enrolling in a virtual power plant (VPP)—that can increase your overall savings.

The payback period for a standalone battery is harder to calculate than for solar, because your primary benefit is insurance-style protection rather than direct savings. If you're primarily buying for outage backup, you're paying for peace of mind. If you're also using it for TOU arbitrage, your utility bills will tell you fairly quickly whether it's paying off.

This is where a lot of homeowners get surprised. A 13.5 kWh battery (the capacity of a single Tesla Powerwall 3) may sound like a lot, but what it can power depends entirely on how your appliances pull energy from it.

If you're running only essential loads—a refrigerator, a few lights, phone chargers, and maybe a gas furnace's fan motor—you might get two to three days out of one battery during an outage. But if you're also running a central air conditioner, heat pump, or an electric water heater, that time drops to less than a day. A 5-ton central AC unit can draw 3.5 kW or more when running, which means a fully charged single battery could be drained in a few hours of continuous use.

Most battery installers will work with you on what’s called a critical loads panel—a separate electrical subpanel that connects only your essential circuits to the battery. This lets you be strategic about which appliances will use power from your battery rather than trying to run your whole home through it. Even then, if you need whole-home backup or extended power for several days, you'll likely need multiple batteries. Some homeowners in high-outage-risk areas install two or three units.

A standalone battery is useful on its own, but the real benefit comes when you add solar to the system. A grid-tied battery without solar is, effectively, a one-time reserve. Once it's empty, you're waiting for the grid to come back on like everyone else. Add solar panels, and your battery charges every day the sun comes out, which means a multi-day outage becomes much more manageable.

Beyond outage resilience, solar panels improve the financial case. The average EnergySage shopper with a 12 kW solar panel system pays about $30,505 (before incentives) and saves an average of $61,093 on electricity over 25 years. The savings range is wide ($37,000 to $154,000), depending on where you live and how much electricity you use, but for most homeowners in most states, solar pays for itself. The average payback period on our Marketplace is about 10 years.

A battery alone won't generate those kinds of returns. It reduces your exposure to rate fluctuations and protects you during outages, but batteries themselves don’t produce any energy. Solar, combined with a battery, both produces electricity and stores it—which is why the two work better together than either does alone.

If adding solar right now isn't in the cards, that's a valid decision. Just know that most modern batteries are designed to pair with solar panels down the road.

The best battery for your home depends on a few things: how much backup capacity you want, what loads you need to power, and whether you have any interest in pairing with solar in the future.

If your main goal is outage protection for essentials only, a single 10–13.5 kWh battery is likely enough. If you want to run more of your home or need coverage for multiple consecutive days, plan for two or more units.

For homeowners who eventually want to add solar, it's worth choosing a battery that's solar-compatible from the start rather than buying equipment you'll need to replace later. Most reputable installers can help you think through that tradeoff.

The most useful thing you can do before committing is get a few quotes. Battery pricing varies more than most people expect, and what an installer proposes for your specific home matters more than a national average. EnergySage's Marketplace makes it easy to compare quotes from pre-vetted installers in your area, whether you're looking at battery-only or battery-plus-solar. Our Energy Advisors can also help you think through which setup actually makes sense for your situation at no cost to you.