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The storm takes the power out a little after midnight. In most houses on the street, that means silence, a warm fridge by morning and a scramble for flashlights. In one house, the lights blink for a moment and stay on. The fridge keeps humming, the Wi-Fi never drops and the sump pump in the basement keeps doing its job. Nobody has to go outside to start anything, and there’s no engine noise and no exhaust. That house has a home battery backup.
In short: a home battery backup is a large battery wired into your home’s electrical panel that switches on automatically when the grid fails. A typical installed system stores 10 to 15 kWh, enough for essentials (fridge, lights, Wi-Fi, a sump pump) for two to four days, but only about half a day for an average whole home. EnergySage puts the average installed cost at about $1,159 per kWh in 2026.
This page starts our Home Battery Backup section: how home batteries work with and without solar, whole-home vs essentials, sizing, outage runtimes, 2026 costs, how they compare with generators and power stations, and our picks.
Home battery backup at a glance
- What it is: a battery, an inverter and a switching device (gateway, transfer switch or smart panel) that keeps your house circuits powered when the grid goes down.
- Two kinds: installer systems that are bolted to a wall and wired in (Tesla Powerwall 3, Enphase IQ Battery, FranklinWH aPower 2, Generac PWRcell 2), and plug-in, expandable kits you buy yourself and connect through an electrician-installed panel (EcoFlow DELTA Pro Ultra, Anker SOLIX E10, BLUETTI Apex 300, Jackery HomePower 3000).
- Two numbers matter: kWh (how much energy it stores, which decides how long it lasts) and kW (how much it can deliver at once, which decides what it can run).
- Solar is optional: a battery can charge from the grid and wait for an outage. Solar lets it refill during a long one.
- Silent and fuel-free: no exhaust, no carbon monoxide, no gasoline to store.
- Cost: about $15,647 installed for a 13.5 kWh system on average (EnergySage, 2026 quotes); plug-in kits start around $1,349 for 3 kWh plus an electrician’s bill.
- No federal tax credit in 2026: the 25D residential clean energy credit ended for systems installed after December 31, 2025. State and utility programs remain in some places.
What is a home battery backup and how does it work?
Every home battery system has three jobs: store energy, turn it into the 120/240 V AC power your house uses, and separate your home from the grid the instant the grid fails. That last part matters. When the power goes out, the system opens a switch so your battery isn’t feeding the utility lines (that would endanger line workers), then powers your circuits on its own. Tesla calls this box a Backup Gateway, Enphase an IQ System Controller, FranklinWH an aGate, Generac a Smart Disconnect Switch, and EcoFlow and Anker a smart home panel or power dock.
In normal times the battery sits charged. Many systems also do day-to-day work: storing solar power for the evening, or charging when electricity is cheap and discharging when it’s expensive on a time-of-use rate. When an outage hits, the switchover takes milliseconds; makers quote 20 ms or less for the EcoFlow Smart Home Panel 2 and the Anker SOLIX E10. Most people notice a blink, if anything.
Installer systems vs plug-in expandable kits
Installer systems are sold and installed through the maker or its certified installers. You get a quote, a permit, a fixed wall or ground mount (often outdoors) and one warranty for the whole job. They store 5 to 15 kWh per unit and stack for more. You can’t buy them on Amazon.
Plug-in expandable kits are big power stations on wheels with add-on batteries. You can buy and use one tomorrow with extension cords. To power house circuits automatically, you add the maker’s panel or dock, and that part must be installed by a licensed electrician. EcoFlow says its Smart Home Panel 2 “requires installation before use,” and Anker says an electrician is required for the E10’s Power Dock or Smart Inlet Box. The upside: a lower starting price, and you can take the battery with you if you move.
Do you need solar for a home battery?
No. A home battery can charge from the grid and hold that energy until an outage. FranklinWH, for example, says the aPower 2 stores energy “from solar, grid, generator, and EV.” Every plug-in kit in our picks charges from a wall outlet too.
What solar adds is staying power. Without it, a battery is a fixed tank: when it’s empty, it’s empty until the grid comes back. With solar, it refills on sunny days, so a long outage becomes a matter of using less at night rather than running out. Powerwall 3 has a solar inverter built in (up to 20 kW of panels on Tesla’s datasheet), and Enphase batteries are designed to work with Enphase microinverter solar. The plug-in kits take solar directly too: up to 5,600 W on the EcoFlow DELTA Pro Ultra and 9 kW on the Anker SOLIX E10, per their makers.
Without solar you also give up most of the money-saving side, unless your utility has time-of-use rates or pays battery owners to share power at peak times. Our guide to the best home battery backup without solar goes through the options.
Whole-home backup or essential loads?
This is the biggest decision, and it drives both size and cost.
- Essential loads (partial backup): the installer moves your most important circuits (fridge, a few lights and outlets, Wi-Fi, furnace blower, sump or well pump) to a separate backup panel, or a smart panel picks them. The battery only feeds those. A smaller battery lasts days this way. The Jackery HomePower 3000 with a manual transfer switch (up to 6 circuits) and the EcoFlow Smart Home Panel 2 (12 circuits) work like this.
- Whole-home backup: the switching device sits between the meter and your main panel, so every circuit stays live. It’s simpler to live with, but the battery’s power limit still applies: an electric range, a dryer and central air all at once can overload it. Installers often add load controllers that shed big appliances during an outage. FranklinWH says one aPower 2 can power an entire home, including A/C, and Generac says PWRcell 2 supports whole-home backup up to 200 A service.
Whole-home means every circuit is available, not that everything can run at once forever; runtime still depends on what you switch on.
How to size a home battery: kWh and kW
Sizing takes two numbers: energy (kWh) for how long, and power (kW) for what can run at the same time.
- List what must run. Fridge, freezer, lights, Wi-Fi, sump or well pump, furnace blower, medical devices. Decide whether you want anything big (central AC, an electric water heater, a well pump on 240 V).
- Add up energy per day. Use yearly kWh for fridges and freezers (from the ENERGY STAR label or the yellow EnergyGuide label), and watts × hours for everything else.
- Pick the outage length you want to ride out. One day? Three? Multiply. If you have solar, the battery only needs to cover the nights.
- Check power and starting surge. Add the watts of everything that could run at once and compare with the battery’s continuous kW. Motors (pumps, AC compressors) pull a big burst when they start; installers compare the motor’s locked-rotor amps (LRA) with the battery’s rating. Tesla lists 185 A LRA for Powerwall 3, FranklinWH 185 A for aPower 2, Anker 155 A for the E10 with two or more batteries, and Enphase up to 90 A for the IQ Battery 10C.
- Leave headroom. Batteries are often kept partly charged for daily savings, cold weather slows them, and plug-in units lose some energy in the inverter. We count 85% of a plug-in unit’s rated capacity as usable.
An outage-day energy budget
| Load (source of the number) | Energy per day |
|---|---|
| Full-size top-freezer fridge (median ENERGY STAR model, 363 kWh/year) | ≈995 Wh |
| Chest freezer (median ENERGY STAR full-size model, 218 kWh/year) | ≈600 Wh |
| Modem and router, 20 W together (example; check your adapters’ labels), 24 hours | ≈480 Wh |
| Five 9 W LED bulbs, 5 hours each (bulb label) | ≈225 Wh |
| Laptop on a 65 W charger, 2 hours (adapter label) | ≈130 Wh |
| Zoeller M53 sump pump: 9.7 A × 115 V ≈ 1,116 W, if it runs 1 hour in total (Zoeller specs) | ≈1,116 Wh |
| Essentials total | ≈3.5 kWh |
| Average US home, everything (EIA: 10,791 kWh a year in 2022) | ≈29.6 kWh |
The gap between those two totals is the whole story of home battery sizing. Essentials are cheap to back up; heating, cooling, water heating and cooking are what make whole-home backup expensive. If your heat is a gas furnace, its blower and controls are usually a modest load; if your heat or hot water is electric, plan on far more.
How long does a home battery last in a power outage?
Divide usable kWh by your daily use. For installer systems we use the maker’s usable figure as is; for plug-in units we take 85% of rated capacity. These are our estimates before any solar recharge, not maker claims.
| Battery (usable kWh) | Essentials (≈3.5 kWh/day) | Average whole home (≈29.6 kWh/day) |
|---|---|---|
| BLUETTI Apex 300 (≈2.35) | ≈16 hours | ≈2 hours |
| Jackery HomePower 3000 (≈2.6) | ≈18 hours | ≈2 hours |
| EcoFlow DELTA Pro Ultra or Anker SOLIX E10, one battery (≈5.2) | ≈1.5 days | ≈4 hours |
| Enphase IQ Battery 10C (10) | ≈2.8 days | ≈8 hours |
| Tesla Powerwall 3 (13.5) | ≈3.8 days | ≈11 hours |
| FranklinWH aPower 2 (15) | ≈4.2 days | ≈12 hours |
| DELTA Pro Ultra with five batteries (≈26.1) | ≈7.4 days | ≈21 hours |
| Two Powerwall 3 units (27) | ≈7.6 days | ≈22 hours |
Real homes vary a lot: a hot afternoon with central air running, or a cold night with electric heat, can empty a battery many times faster than the essentials line suggests. The practical answer for most families is to back up essentials for several days, or the whole home for a night, and add solar if outages last longer where you live. Our guide on how long a home battery lasts and how many batteries you need works through more examples.
Two cheap tricks stretch any battery. Ready.gov says a closed fridge keeps food cold for about four hours and a full freezer holds its temperature for about 48 hours, so they don’t need power every minute. And turning off the biggest loads you don’t need (the water heater, the dryer, extra AC zones) buys hours.
How much does a home battery backup cost in 2026?
Installer systems: EnergySage says the average battery cost on its marketplace is $1,159 per kWh of stored energy, or $15,647 installed, based on quotes for a 13.5 kWh system like a Tesla Powerwall 3 (page updated August 2026). That’s before any state or local incentives. A second battery costs less per kWh than the first, because the gateway and much of the labor are already paid for, but installed prices vary widely by home and region. Get two or three quotes.
Plug-in expandable kits (makers’ own prices, October 2026):
| Kit | What’s included | About (maker, Oct 2026) | Per kWh of battery |
|---|---|---|---|
| Jackery HomePower 3000 | 3.072 kWh unit | $1,349 | ≈$439 |
| BLUETTI Apex 300 | 2.76 kWh unit | $1,499 | ≈$542 |
| Anker SOLIX E10 | Power module + one 6.144 kWh battery | $3,999 ($5,799 with Power Dock) | ≈$651 |
| EcoFlow DELTA Pro Ultra | Inverter + one 6.144 kWh battery | $4,199 ($5,599 with Smart Home Panel 2) | ≈$683 |
Add the electrician’s work for the panel, dock or transfer switch, plus a permit where your town requires one. Ask for a written quote before you buy, because an older panel may need upgrades.
Incentives: there’s no federal tax credit for a home battery installed in 2026; the 25D residential clean energy credit ended for installations completed after December 31, 2025. EnergySage notes you can still benefit from the business version of the credit indirectly if you lease a battery. Some states and utilities pay too. California’s SGIP closed its ratepayer-funded budgets at the end of 2025, while a state-funded budget for income-qualified homes continues. In Massachusetts, the Mass Save ConnectedSolutions program pays battery owners for sharing stored power during summer peaks. Many utilities run similar “virtual power plant” programs. Search your ZIP code on DSIRE and ask your utility. Our home battery backup cost guide has the full breakdown.
Home battery vs generator vs portable power station
| Home battery | Standby generator | Portable generator | Portable power station | |
|---|---|---|---|---|
| Switches on by itself | Yes, in milliseconds | Yes, within seconds | No, you start it and connect it | Only for what’s plugged in (or with a maker panel) |
| How long it runs | Until the kWh run out (or forever with enough solar) | As long as natural gas or propane lasts | One tank, then refuel | Until the battery runs out |
| Fuel, exhaust, noise | None | Natural gas or propane, exhaust, about 65–69 dB(A) running on maker sheets | Gasoline or propane, carbon monoxide, loud | None |
| Example price | About $15,647 installed for 13.5 kWh (EnergySage average) | Generac Guardian 22kW from $6,119 MSRP, unit only, before installation | Westinghouse WGen9500DFc $1,399 list | EcoFlow DELTA Pro 3, about $2,799 (maker sale) |
| Installation | Licensed installer or electrician | Dealer: pad, gas line, transfer switch, permit | Electrician for an inlet and transfer switch | None for cords; electrician for a panel |
A standby generator wins on endurance: on a natural gas line it can run a whole house, central air included, for a week-long outage. Watch the ratings on gas, though: Generac’s 22 kW Guardian is rated 19.5 kW on natural gas. A home battery wins on quiet, zero maintenance, no fumes and everyday savings, and with solar it can ride out long outages too. Some homes combine both: Generac says PWRcell 2 can work with a Generac standby generator up to 28 kW. Read more in home battery backup vs generator and in our home generators guide.
A portable power station is the low-cost entry point: no installation, safe indoors, and enough for a fridge and Wi-Fi for a day. See portable power stations and the best portable power station for home backup. The bigger ones blur into home batteries once you add a maker’s home panel.
Installation and safety
- Anything connected to your house wiring is installed by a licensed electrician, with a permit where required. That covers installer systems and the panels, docks and transfer switches for plug-in kits.
- Never backfeed. Don’t plug a battery, power station or generator into a wall outlet with a double-ended cord. FEMA warns that power fed into a wall outlet can flow back onto utility lines and electrocute line workers or neighbors. CPSC adds that backfeeding bypasses some of your home’s built-in circuit protection.
- Look for safety listings. EcoFlow lists UL 9540 and UL 1973 for the DELTA Pro Ultra, and Enphase says the IQ Battery 10C was evaluated to UL 9540A. Your installer and local code decide where a battery may go (garage wall, outside wall, distance from doors and windows).
- Mind the temperature. Batteries have charging limits in the cold. Enphase lists –4°F to 122°F for charging the IQ Battery 10C. Plug-in units are usually kept indoors.
- Medical devices: if someone at home depends on oxygen, a CPAP or other equipment, talk to your doctor or equipment supplier about an outage plan, and tell your utility. Jackery, for example, says its power stations are not recommended for medical or life-support equipment.
Batteries make no carbon monoxide, but generators do. If you also run a generator, CPSC says to run it outdoors only, at least 20 feet from the house, with the exhaust pointed away from the home, never in a garage, and to keep battery-powered CO alarms on every level.
The best home battery backup systems in 2026
Prices change often. The prices below are what we saw at the maker in October 2026; check the current price before you buy. Installer systems have no public price; get quotes.
Tesla Powerwall 3
- 13.5 kWh usable
- 11.5 kW continuous, built-in solar inverter
- Sold and installed by Tesla and certified installers
FranklinWH aPower 2
- 15 kWh, 10 kW continuous
- Expands to 225 kWh
- 15-year warranty (60 MWh)
Enphase IQ Battery 10C
- 10 kWh, 7.08 kVA, LFP
- Modular, stack more units
- 15 years or 6,000 cycles
EcoFlow DELTA Pro Ultra
- 6.144 kWh per battery, 7.2 kW, 120/240 V
- Expands to 90 kWh
- About $4,199 (maker, Oct 2026)
Anker SOLIX E10
- 6.144 kWh per battery, 7.68 kW
- NEMA 4 (IP66) outdoor
- About $3,999 (maker, Oct 2026)
Jackery HomePower 3000
- 3,072 Wh, 3,600 W
- Pairs with a 6-circuit transfer switch
- About $1,349 (maker, Oct 2026)
- Tesla Powerwall 3: 13.5 kWh and up to 11.5 kW in one wall unit, with a solar inverter built in and room for more units. Tesla’s warranty is 10 years with 70% capacity retained. Installed through Tesla and certified installers.
- FranklinWH aPower 2: the most energy per unit here (15 kWh, 10 kW), LFP chemistry, and a 15-year warranty. It stores power from solar, the grid, a generator or an EV, through FranklinWH’s aGate.
- Enphase IQ Battery 10C: 10 kWh per unit with built-in microinverters, LFP chemistry and a warranty of 15 years or 6,000 cycles (to 60% capacity). The natural choice if you already have Enphase solar.
- EcoFlow DELTA Pro Ultra: 7.2 kW at 120/240 V, starting at 6.144 kWh and growing to 30 kWh per inverter. Add the electrician-installed Smart Home Panel 2 for automatic backup.
- Anker SOLIX E10: a weatherproof (NEMA 4/IP66) power module with 7.68 kW and up to five batteries, plus 9 kW of solar input. Electrician-installed Power Dock or Smart Inlet Box.
- Jackery HomePower 3000: a 3 kWh essentials battery with 3,600 W of output; pair it with a manual transfer switch (up to six circuits) installed by an electrician. Not expandable.
We researched and compared these from the makers’ spec sheets and warranties; we didn’t test them. Full reviews, Generac PWRcell 2 and BLUETTI Apex 300 included, are in the best home battery backup. Choosing between the two biggest names? Read Tesla Powerwall vs Enphase and our Tesla Powerwall 3 review.
Which guide do you need?
| If you want to… | Read |
|---|---|
| Compare the best systems, installer and plug-in | Best home battery backup |
| Back up a home with no solar panels | Best home battery backup without solar |
| Know what you’ll pay, installed | Home battery backup cost |
| Decide between a battery and a generator | Home battery backup vs generator |
| Choose between the two best-known systems | Tesla Powerwall vs Enphase |
| Look closely at the Powerwall 3 | Tesla Powerwall 3 review |
| Work out runtime and how many batteries you need | How long does a home battery last? |
| Start smaller, with no installation | Best portable power station for home backup |
| Look at generators instead | Home generators |
For the bigger picture, see how batteries store chemical energy, how they pair with solar energy, and how backup generators run on natural gas, propane or gasoline. Browse every article in our home battery backup and generators categories.
Home battery backup questions
Can a home battery power my whole house?
Yes, if it’s wired for whole-home backup and its power rating covers what runs at once. A 13.5 kWh battery runs an average home for roughly 11 hours by our estimate, and essentials for close to four days. Big loads like electric heat, ranges and central air drain it fast, so most whole-home systems use load management or more than one battery.
How long does a home battery backup last?
In an outage, divide usable kWh by your daily use: a 10 to 15 kWh battery covers about 3.5 kWh of daily essentials for roughly three to four days. Over its life, EnergySage says most batteries last about 10 to 15 years. Warranties differ: Tesla 10 years, Enphase and FranklinWH 15 years, each with its own capacity and energy limits.
Do I need solar panels to get a home battery?
No. Batteries charge from the grid and stand by for outages; FranklinWH, for example, stores energy from the grid, solar, a generator or an EV. Without solar, though, the battery can’t refill during a long outage, and you’ll save less money day to day unless your utility has time-of-use rates or a battery program.
How much does a home battery backup cost?
EnergySage’s 2026 average is about $1,159 per kWh installed, or $15,647 for a 13.5 kWh system, before incentives. Plug-in kits start lower: about $1,349 for a 3 kWh Jackery HomePower 3000 or about $4,199 for an EcoFlow DELTA Pro Ultra with one battery, plus an electrician for the home connection. Get two or three quotes.
Is there a tax credit for home batteries in 2026?
Not a federal one. The 30% residential clean energy credit (25D) ended for batteries and solar installed after December 31, 2025. Some states and utilities still offer rebates or pay battery owners to share power at peak times, such as Mass Save’s ConnectedSolutions in Massachusetts. Check DSIRE and your utility before you sign.
Is a home battery better than a generator?
It depends on your outages. A battery is silent, fume-free and switches on instantly, but it holds a fixed amount of energy unless you have solar. A natural gas standby generator runs a whole house for days, but needs fuel, maintenance and a safe outdoor spot. For frequent short outages, a battery suits most homes; for week-long ones without solar, a generator wins.
Can I install a home battery myself?
You can set up a plug-in battery and run appliances from it with cords. Connecting any battery to your home’s wiring (a panel, dock, inlet or transfer switch) must be done by a licensed electrician, with a permit where required. Installer systems like Powerwall, Enphase and FranklinWH are only sold and installed through the maker or certified installers.