Tesla Powerwall 3 Explained: Specs, Cost, Warranty and How It Works With Solar

The Tesla Powerwall 3 is a 13.5 kWh home battery with a built-in solar inverter and 11.5 kW of continuous output, enough power for many whole-home backup setups. It stores solar or grid energy for use at night, during peak-rate hours or in an outage. In EnergySage's first-half 2026 data, Tesla batteries averaged about $967 per kWh, or roughly $13,055 for a 13.5 kWh system before incentives.

Key takeaways

• Powerwall 3 combines a battery and a hybrid solar inverter with six solar inputs and up to 20 kW of DC solar.
• One unit stores 13.5 kWh and delivers 11.5 kW continuously. A system can hold up to four Powerwall 3 units plus three Expansion units.
• Tesla's US warranty covers 10 years with 70% energy retention.
• Powerwall 3 needs a grid connection. Tesla does not support fully off-grid systems with it.
• The federal residential clean energy credit does not apply to expenditures made after December 31, 2025.

What is the Tesla Powerwall 3?

Powerwall 3 is Tesla's third-generation home battery. Unlike the Powerwall 2, which Tesla describes as designed to be added to existing solar, Powerwall 3 has an integrated solar inverter. Solar panels can wire straight into it.

That makes Powerwall 3 a DC-coupled battery in most new installs. Berkeley Lab noted that the 2025 shift toward Powerwall 3 systems, which are typically DC-coupled, contributed to a sharp drop in the use of panel-level power electronics on new home solar.

Like other home batteries, Powerwall 3 can:

• Store extra midday solar for the evening
• Cover expensive peak hours on a time-of-use plan
• Run your home or chosen circuits during a grid outage, with a Tesla gateway or backup switch

Tesla Powerwall 3 specs

These figures come from Tesla's North American datasheet and installation manual, checked November 2026.

Tesla's installation manual also lists 15.4 kW of off-grid discharge when powered by solar alone in cooler conditions. The battery is rated NEMA 3R, can be floor or wall mounted and is listed at under 50 dB(A) typical noise at 1 meter.

Installation and placement

Powerwall 3 does not switch your home to backup on its own. Tesla's datasheet describes Gateway 3 and Backup Gateway 2 as providing automatic disconnect for backup, and the Backup Switch also detects outages automatically. Tesla's design guide lists Backup Gateway 1 as not compatible. Your quote should name which device you are getting.

Other installation details from Tesla's documents:

• The battery and power electronics are rated IP67, and the enclosure is NEMA 3R, so outdoor installs are common.
• Tesla limits systems to three Powerwall 3 units in outdoor wall-mount or indoor setups (detached garages and storage sheds are excepted).
• Output is derated above 104°F, so a shaded spot helps in hot climates.
• For solar rapid shutdown, Tesla's specifications list Tesla Mid-Circuit Interrupters, so ask how your array will meet this requirement.

Sizing a Powerwall 3 system

Berkeley Lab found that the median home battery installed in 2025 was 13.5 kWh, the size of one Powerwall. It also found that battery power ratings rose sharply in 2025 because Powerwall 3 has much higher output than earlier models.

When sizing, think about both energy and power:

• Energy: Each Powerwall 3 or Powerwall 3 Expansion adds 13.5 kWh. Tesla's design guide allows up to four Powerwall 3 units and up to three Expansion units per system.
• Power: Tesla recommends that total Powerwall supply be able to power the single largest automatic load in the backup circuit, such as a central air conditioner or well pump.
• Backup scope: Powerwall 3 supports whole-home or partial-home backup.

Our guide on how big a solar battery you need walks through a load list step by step.

How much does a Tesla Powerwall 3 cost?

Here are the dated price points we could verify. Your quote will depend on your home's wiring, location and installer.

Among the brands EnergySage listed, Tesla had one of the lower average prices per kWh. Extra costs can include a main panel upgrade, a backup gateway or added solar.

Tax credit: The IRS says the residential clean energy credit is not available for expenditures made after December 31, 2025. A Powerwall 3 whose installation is completed in 2026 does not qualify, even if older sales materials say otherwise.

Adding Powerwall 3 to existing solar or an older Powerwall

Powerwall 3 can work with existing panels, but there are limits:

• DC-coupled: Existing panel strings can be rewired into the Powerwall 3's inverter. Tesla says third-party optimizers wired to the Powerwall 3 are not compatible.
• AC-coupled: Powerwall 3 works with AC-coupled solar from Tesla or third-party inverters. With AC-coupled solar only, Tesla allows a maximum of 7.68 kW AC per Powerwall in the backup circuit, or up to 10 kW with Expansion units at certain settings.
• Older Powerwalls: Tesla's own information conflicts, as checked in November 2026. Its US "Combining Systems" support page still says Powerwall 3 cannot be added to a Powerwall 2 or Powerwall+ system. But Tesla's US installer design guide lists Powerwall 2 as compatible, links to an application note on installing Powerwall 3 in an existing Powerwall 2 system, and lists Powerwall+ as not compatible. Tesla's backward-compatibility support page says Powerwall 2 systems need software version 26.26 or later, that Gateway 1 and Neurio meters are not supported, and that supported setups include up to four Powerwall 2 units, one Powerwall 3 and up to three Expansion units. That page appears to be written for Australia and New Zealand. If you own a Powerwall 2 or Powerwall+, ask Tesla or a Tesla Certified Installer to confirm in writing what your system supports.

Read our full guide to adding a battery to an existing solar system.

Backup power vs bill savings with Powerwall 3

For backup, the Powerwall 3's 11.5 kW output and 185 A motor-start rating help it run large appliances. Tesla's specifications list a higher off-grid discharge rating (15.4 kW) when the system runs on solar in cooler conditions, which shows solar wired to the system can keep supplying power while the grid is down.

For savings, Tesla's warranty describes solar self-consumption and time-based control modes, which let the battery store solar and use it during expensive hours. Tesla also says recent installs can charge from the grid if the installer and owner allow it. This pays most on time-of-use rates or where export credits are low. In California, the CPUC says net billing customers get export credits usually below the retail rate, and that storage helps maximize savings. If you still have full retail net metering, the savings case is weaker. See are solar batteries worth it.

Powerwall 3 warranty and lifespan

Tesla's US Powerwall warranty covers Powerwall 3 for 10 years from installation. Key terms:

• Energy retention: 70% of the 13.5 kWh rating at 10 years.
• Cycles: Unlimited for solar self-consumption, time-based control and backup. For other uses, coverage is limited to 37.8 MWh of throughput.
• Internet connection: If a Powerwall is offline for an extended period, Tesla says it may not honor the full 10 years. It promises at least four years either way.
• Transfer: A later owner with proof of ownership can make warranty claims.

Tesla also says relocating the unit without its written consent is excluded, so check with Tesla before you move a Powerwall.

Next steps

Compare Powerwall 3 with rivals in our Powerwall 3 vs Enphase IQ Battery guide. Then check quotes with the solar quote checker.