FranklinWH Battery (aPower 2): Cost, Specs, and Is It Worth It? (2026)

What is the FranklinWH battery?

The FranklinWH battery is an AC-coupled lithium iron phosphate (LFP) home battery made of two parts: the aPower 2, which stores the energy, and the aGate, the controller that runs the whole system. The aPower 2 has its own built-in battery inverter to turn stored DC into household AC, but because the system is AC-coupled it does not replace your solar inverter. That is the design's main practical advantage: it bolts onto an existing solar array of almost any brand, which makes it one of the easier home batteries to add to a system you already own. It does the same core job as any home solar battery, turning daytime solar into around-the-clock power and keeping the house running through an outage.

The aGate is what sets FranklinWH apart. It is a smart microgrid controller that sits between the grid and your home, disconnects automatically when the grid fails, and switches to battery power fast enough that most electronics never blink. It also coordinates four power sources at once: solar, grid, the aPower 2 batteries, and a backup generator. That generator integration is uncommon in this class and is a real reason people pick FranklinWH over rivals. You watch and control everything from the FranklinWH app, which shows live production, home use, and battery level. Despite people calling it a 'Franklin Powerwall,' it is not a Tesla product; it is its own system from a separate company.

How much does a FranklinWH aPower 2 cost in 2026?

The equipment for a FranklinWH system, one aPower 2 plus the required aGate, costs roughly $10,000 to $12,000, and installed you should expect somewhere around $15,000 to $20,000 for the first battery, which works out to about $1,000 to $1,350 per usable kWh. The install total includes the battery, the aGate, wiring into your main panel, and permits, and the cost per kWh drops as you add more aPower 2 units because they share one aGate and much of the labor. Bundling the battery into a new solar install is usually cheaper than adding it later. These are estimates that move with your installer, your region, and how much electrical work your panel needs, so treat any quote as specific to your home and see our disclaimer.

One thing changed for 2026: a battery you buy and own no longer qualifies for the 30% federal residential tax credit. The Section 25D credit that used to cover home batteries of 3 kWh or more expired for anything placed in service after December 31, 2025, so do not budget around a federal credit that is gone. Only third-party leases and power-purchase agreements can still reach a federal credit, and it is claimed by the system owner, not you. Some states and utilities still offer storage rebates, and those vary widely and change often, so check your current local programs. The full picture is in is there a federal solar tax credit in 2026.

What are the FranklinWH aPower 2 specs?

The aPower 2 holds 15 kWh of usable energy and delivers 10 kW of continuous power, with a 15 kW peak for 10 seconds that FranklinWH rates to start a 5-ton central air conditioner. It charges at up to 8 kW, uses lithium iron phosphate (LFP) cells, and runs at about 90% round-trip efficiency, meaning you get back roughly 90 cents of every dollar of energy you put in. It carries a 15-year warranty or 60 MWh of energy throughput, whichever comes first, which is one of the longer coverage terms among home batteries.

Those numbers make the aPower 2 a high-power, high-capacity single unit. Its 15 kWh beats most single-enclosure rivals, and its 10 kW continuous output with a 15 kW surge is enough to run demanding loads like an air conditioner, well pump, or electric range that trip up smaller batteries. You scale a system by adding more aPower 2 units to one aGate, up to 15 units for 225 kWh total, far more than a typical home will ever need. For how these kWh and kW ratings translate into real runtime for a fridge, lights, or an air conditioner, the watt-hour math is walked through in solar batteries explained, and the LFP chemistry itself is compared to other lithium types in LiFePO4 vs lithium-ion.

FranklinWH vs Tesla Powerwall: which should you get?

Get the FranklinWH aPower 2 for whole-home backup and retrofits, and the Tesla Powerwall 3 for a new solar-plus-storage build. The aPower 2 wins on raw capacity and surge, 15 kWh and a 15 kW peak against the Powerwall 3's 13.5 kWh and 11.5 kW continuous, and its AC-coupled design drops onto an existing array of any brand without touching your solar inverter. The aGate's ability to fold a backup generator into the system is something the Powerwall does not match, which matters if you want batteries for daily use plus a generator for multi-day outages.

The Powerwall 3 answers back with a solar inverter built into the battery, so on a brand-new install it replaces a separate string inverter and can be cheaper and cleaner in one box, and its 11.5 kW continuous output is higher than the aPower 2's 10 kW for sustained heavy loads. Both use LFP chemistry and both back up a whole home well. If you are installing solar and storage together from scratch, the Powerwall 3's integrated inverter usually gives the better value; if you are adding storage to existing panels, want generator integration, or need the extra capacity and surge, the aPower 2 is the stronger pick. See the full Tesla Powerwall writeup for its cost and specs, and the modular Enphase IQ Battery for a third approach that adds storage in small blocks.

How many FranklinWH batteries do you need?

For most homes, one aPower 2 (15 kWh) covers a whole-house backup for essentials plus some comfort loads through an evening or a short outage, running a fridge, lights, internet, outlets, and even an air conditioner for a while. To carry a whole house overnight including central heating or air conditioning, many owners add a second unit for 30 kWh, since the average US home uses around 30 kWh a day. The high 10 kW output means a single aPower 2 handles big appliances that would overwhelm a smaller battery, so you often need fewer units than the raw capacity comparison suggests.

Size the battery to your backup goal, not your entire power bill. Decide which circuits you need to keep alive and for how long, add up their daily watt-hours, and buy enough usable kWh to cover that window with margin. The aGate lets you set priority circuits so the battery protects what matters most first. The panel side is a separate calculation: size your array to your usage with the solar panel calculator, and remember the battery only has to be big enough for the loads you want to protect. For ready-to-compare home units beyond FranklinWH, see the best solar battery backup for home.

Is the FranklinWH battery worth it?

A FranklinWH battery is worth it in three situations. First, if you get frequent or long outages and want true whole-home backup, the aPower 2's high output and the aGate's generator integration make it one of the best home batteries for keeping a full house, not just a few circuits, running through a blackout. Second, if your utility has weak net metering or net billing that pays little for exported power, storing your surplus instead of selling it cheap recovers much of that lost value; weigh the export side in how net metering works. Third, on steep time-of-use rates, the battery charges on cheap daytime solar and discharges during the expensive evening peak.

FranklinWH's specific edge is power and flexibility in one box. The 10 kW continuous output and 15 kW surge start heavy loads that smaller batteries cannot, the AC-coupled design makes it a clean retrofit onto existing solar, and the aGate is the only controller in its class that manages solar, grid, battery, and a generator together. The LFP chemistry runs cooler and safer than older lithium types, and the 15-year, 60 MWh warranty is generous. The tradeoffs: it is a large, premium unit, so it costs more upfront than an essentials-only battery, and its continuous output trails the Powerwall 3 slightly. If you are on full-retail net metering with a reliable grid and rarely lose power, a battery of any brand is mostly a comfort and backup purchase rather than a money-saver, especially now that the federal credit is gone. Compare it head to head with other home units in the best solar battery backup for home.

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