FranklinWH Battery: Cost, Key Features, and Installer Reviews

By Sam Wigness · Updated October 2026

Want one battery that can run your whole house? FranklinWH is probably on your list.

The FranklinWH aPower 2 is a 15 kWh home battery with 10 kW of continuous power, run by a controller called the aGate. Installed with new solar, it costs a median of about $17,250 on our marketplace, or about $1,150 for each kWh you can use. It fits homes that want whole-home backup, and homes adding a battery to solar they already have.

Jump ahead:

• FranklinWH specs at a glance
• How much does a FranklinWH battery cost?
• How the FranklinWH system works
• How FranklinWH compares
• What owners say
• Pros and cons
• Who it fits
• Frequently asked questions

FranklinWH specs at a glance

FranklinWH sells two batteries today. The aPower 2 adds to almost any solar system, and the aPower S has a solar inverter built in, for up to 20 kW of panels. Some installers still list the original aPower, which FranklinWH now calls its previous model.

All three use lithium iron phosphate (LFP) cells — a more stable and longer-lasting chemistry than other lithium-ion types, such as NMC.

	aPower 2	aPower S	Original aPower
Usable capacity	15 kWh	15 kWh	13.6 kWh
Continuous power	10 kW	11.5 kW with solar input, 10 kW from the battery alone	5 kW
Peak power	15 kW for 10 seconds	15 kW for 10 seconds	10 kW for 10 seconds
Round-trip efficiency	90%	90.5%, solar to battery to home	89%
Warranty	15 years or 60 MWh	15 years or 60 MWh	12 years or 43 MWh
Batteries per aGate	Up to 15, for 225 kWh	Up to 15, for 225 kWh	Up to 15, for 204 kWh
Weight	357 lb	388 lb	395 lb
Operating temperature	−4°F to 122°F; up to 131°F at reduced power	−4°F to 122°F; up to 131°F at reduced power	−4°F to 122°F
Typical installed price with new solar*	~$17,250	Too few price lists to say	~$14,500

*Median installed price when the battery is added to a new solar system, from the current price lists of installers on the Solar.com marketplace (Sept 2026), before rebates. Specs: FranklinWH data sheets and California's list of certified battery equipment (Oct 2026).

How much does a FranklinWH battery cost?

On our marketplace, an aPower 2 installed with new solar costs a median of about $17,250. About 4 in 10 installers on our marketplace that sell batteries list a FranklinWH battery.

aPower 2, installed	Typical price range*	Median*
With new solar	~$14,700 to $18,100	~$17,250
Added to solar you already have	~$16,000 to $19,600	~$19,000
A second battery adds	~$9,800 to $15,000	~$12,000
Two batteries, 30 kWh, with new solar	~$25,600 to $33,950	~$28,000

*Middle 50% and median of prices on current installer price lists on the Solar.com marketplace, Sept 2026, before rebates. Your price depends on your home, your utility and how many batteries you need. See your real price for your address.

What the numbers tell you:

• Adding it later costs a bit more. The same installer typically charges about $1,500 more to add an aPower 2 to existing solar, because the permits, inspection and labor aren't shared with a solar install.
• Extra batteries cost less than the first. The first battery's price covers the system around it, including the aGate. Two batteries with new solar come to about $930 per kWh.

Is there still a federal tax credit for a FranklinWH battery?

If you buy your battery (cash or loan), there's no federal tax credit in 2026. The homeowner credit ended at the end of 2025. When you add the battery with new solar, the way to still capture that value is a Prepaid TPO (a prepaid lease): a partner owns the system for the first five years, claims the business credit, and passes it to you as an upfront discount on your price. You own it after year five. How the Prepaid TPO works

A Prepaid TPO only covers equipment on the third-party owner's approved vendor list. As of October 2026, FranklinWH batteries aren't on our Prepaid TPO partners' lists, so on our marketplace a FranklinWH battery is a cash or loan purchase. If the Prepaid TPO discount matters to you, ask your installer about a battery that qualifies.

Some utilities and states also offer battery rebates, such as California's SGIP program when funding is open. Your installer should check what applies at your address.

How the FranklinWH system works

A FranklinWH system has two main parts: one or more aPower batteries, and the aGate controller, which serves as the system’s brain.

The aGate: your whole-home backup switch

The aGate connects your solar, the grid, your batteries and your home.

• In an outage, it disconnects your home from the grid and switches to battery power on its own. FranklinWH says always-on appliances, like the fridge and Wi-Fi router, aren't affected.
• Whole home or key circuits: it can back up the whole house from your service entrance, or feed a smaller backup panel. FranklinWH says its 280-amp capacity can help some homes skip a main panel upgrade.
• Add-ons: Smart Circuits let you schedule big loads, like an EV charger, or shut them off in an outage. A Generator module ties in a standby or portable generator.
• Warranty: 12 years, shorter than the battery's 15.

Works with almost any existing solar

The aPower 2 is AC-coupled: it has its own inverter and connects to your home's wiring next to your solar inverter. FranklinWH says the aGate works with both microinverters and string inverters, so the battery adds to most existing systems. Each conversion loses a little energy, and the aPower 2 gives back about 90% of what it stores.

The aPower S takes power straight from your panels, so it fits best when you install solar and a battery together. Both can share one aGate. More in our inverter guide.

What happens in an outage

• The switch is automatic. Owners who've been through outages say they barely notice it.
• It can run big loads. One aPower 2 supplies 10 kW continuously, and FranklinWH says it can start a 5-ton central air conditioner.
• How long it lasts depends on what you run. Roughly, 15 kWh runs 1 kW of essentials for about 15 hours, or central air drawing 4 kW for about 4.
• Solar refills it during the day. If it runs empty in a long outage, FranklinWH's black start feature lets solar charge it back up.

The app

The FranklinWH app shows your solar, battery and home use. You can set the battery to store solar for the evening, to run when your utility's rates are highest, or to stay full for outages. FranklinWH says it can also fully charge before severe weather.

How FranklinWH compares

Here's how the aPower 2 stacks up against the two brands installers on our marketplace list most often: the Tesla Powerwall 3 and Enphase's IQ batteries.

Disclosure: Solar.com is a Tesla Certified Installer.

	FranklinWH aPower 2	Tesla Powerwall 3	Enphase IQ Battery 5P	Enphase IQ Battery 10C
Usable capacity	15 kWh	13.5 kWh	5 kWh	10 kWh
Continuous power	10 kW	11.5 kW	3.84 kW	7.08 kW
Warranty	15 years or 60 MWh	10 years	15 years or 6,000 cycles	15 years or 6,000 cycles
How it connects	Own inverter; adds to almost any solar	Built-in solar inverter	Built-in microinverters; best with Enphase solar	Built-in microinverters; best with Enphase solar
Median installed price with new solar*	~$17,250	~$15,000	~$10,650	~$14,250
Price per usable kWh*	~$1,150	~$1,110	~$2,130	~$1,425

*Median installed price when the battery is added to a new solar system, from the current price lists of installers on the Solar.com marketplace (Sept 2026), before rebates. Specs: makers' data sheets and California's list of certified battery equipment.

What stands out:

• The aPower 2 holds the most in one unit, adds to almost any solar system and has a 15-year warranty.
• The Powerwall 3 supplies a bit more power, has a built-in solar inverter and costs about $2,250 less at the median. Per kWh, the two are close.
• Enphase batteries cost less up front and more per kWh. You stack them to add capacity, and they fit best with Enphase solar.

In our best solar batteries guide, we pick the aPower 2 for whole-home backup.

What owners say about FranklinWH

We read the reviews behind our California installer rankings: 158,781 published reviews of solar installers. More than 160 mention FranklinWH, across more than 60 installers, and most were written in 2025 and 2026. They average 4.8 stars, and more than 9 in 10 give five stars. Those stars rate the installer's whole job, not the battery.

What came up most:

• Outages: owners who've been through them describe a switch they barely notice. The lights don't flicker and the Wi-Fi and freezer stay on. Some only learned about an outage from the app's alert.
• The app: when owners bring it up, it's almost always praise: easy to use, full of detail, with simple schedules. Good installers walk you through it before they leave.
• Install time: the work at your home usually takes one to three days. The wait is for permits, inspection and the utility's approval, which can take weeks or months.
• Service after the install: the best stories are about quick fixes. The few low-star reviews were about installers, not the battery: missed permit steps, setup errors, an unfinished utility hookup or an app login never handed over.
• Adding to existing solar: many reviewers added FranklinWH to solar they already had, including some whose original solar company went out of business.
• One thing to ask about: a couple of owners with Enphase microinverters had monitoring glitches after the battery went in, which their installers fixed. If you have Enphase micros, ask how your installer will handle it.

The takeaway: as with any battery, who installs it matters as much as which battery you pick.

FranklinWH pros and cons

Pros:

• 15 kWh capacity and 10 kW continuous power in one battery: enough for whole-home backup in most homes, including some central air.
• Adds to almost any existing solar system.
• A 15-year warranty that covers up to 60 MWh, or about 4,000 full charges.
• Generator and smart-circuit options built into the aGate.
• Room to grow: up to 15 batteries on one aGate.
• Owners like the app.

Cons:

• A higher price up front than a Powerwall 3 on our marketplace, though the two are close per kWh.
• Fewer installers to choose from: about 4 in 10 installers on our marketplace that sell batteries list FranklinWH, against about 6 in 10 for the Powerwall 3 and more than 8 in 10 for Enphase.
• Big and heavy: 357 pounds and about 45 by 30 inches, so it needs a garage wall, an outside wall or floor space.
• The aGate's 12-year warranty is shorter than the battery's.
• FranklinWH is a younger company. We know of no financial problems, but long-term app and warranty support is worth weighing with any newer battery maker.

Who the FranklinWH battery fits

1. You want whole-home backup, including central air. One aPower 2 with an aGate covers most homes. Add a second for long outages or big loads.
2. You already have solar. The aPower 2 works with almost any inverter. Expect to pay a bit more than adding it with new solar.
3. You're installing solar and a battery together. Compare the aPower 2, the aPower S and the other batteries in our best batteries guide.
4. You want backup for long outages. The aGate's Generator module ties in a generator.
5. You mostly want a lower bill and rarely lose power. A smaller battery, or one without backup, may cost less. See backup vs no-backup batteries, or try our interactive battery explainer on your utility's rates.
6. Your garage gets very hot or cold. The aPower 2 runs from −4°F to 122°F, and up to 131°F at reduced power.

FranklinWH battery FAQs

How much does a FranklinWH battery cost?

On our marketplace, an aPower 2 costs a median of about $17,250 installed with new solar, or about $19,000 added to solar you already have, before rebates. A second battery adds about $12,000.

How much does it cost to add a battery to an existing solar system?

For an aPower 2, the median on our installers' price lists is about $19,000. That's typically about $1,500 more than the same installer charges with new solar, because the permits, inspection and labor aren't shared.

Are FranklinWH batteries any good?

On paper, the aPower 2 is one of the most capable home batteries: 15 kWh, 10 kW of continuous power, LFP cells and a 15-year warranty. Reviews that mention FranklinWH are very positive, but those stars rate installers, not the battery. Most problems we read about were installation or setup errors.

Is FranklinWH better than Tesla?

It depends on your home. The aPower 2 stores more, has a longer warranty and adds easily to existing solar. The Powerwall 3 has more continuous power, a built-in solar inverter and a lower median price on our marketplace: about $15,000, against $17,250. Per kWh, they're close.

What is the warranty on a FranklinWH battery?

The aPower 2 and aPower S are covered for 15 years or 60 MWh of energy, whichever comes first. The aGate has a 12-year warranty.

How many kWh is a FranklinWH aPower 2?

15 kWh usable per battery. You can connect up to 15 batteries to one aGate, for 225 kWh.

Can I get a tax credit for a FranklinWH battery?

Not if you buy it. The federal homeowner credit ended at the end of 2025. A Prepaid TPO can pass the credit's value to you as an upfront discount, but as of October 2026 FranklinWH batteries aren't on our Prepaid TPO partners' approved equipment lists. How the Prepaid TPO works

Get your real FranklinWH price

Your price depends on your roof, your electrical panel, your utility and how much backup you want. See your real price for your address in about 90 seconds, with no sales calls.