What is a Powerwall battery?

Tesla unveiled the Powerwall on April 30, 2015, as the first product of its new Tesla Energy division. On the grid alone, it shifts a home's electricity use away from expensive peak hours; paired with solar, it can keep the house running through long outages.

Inside Powerwall 3

The current version, Powerwall 3, is a flat lithium-ion battery (a chemistry that packs a lot of energy into little weight) that holds 13.5 kilowatt-hours (kWh, the energy a microwave uses running for about an hour) and builds the solar inverter, the part that turns solar panel output into the current your house uses, right into the battery. One unit weighs about 130 kilograms and carries an IP67 rating, which means it is sealed against dust and water and can stay outside through rough weather.

Powerwall Benefits

These are the features Tesla lists for Powerwall 3.

Why the Powerwall Exists

The reasoning Tesla gave was direct. A home makes solar power during the day but needs it most at night, and the grid charges more when everyone wants electricity at once. A battery bridges that gap, storing cheap or self-made power for later, moving your demand off the pricey hours, and keeping the lights on when the utility goes down. The bigger goal, shared across all of Tesla Energy, is to speed up the switch to clean power and lean less on fossil fuels. Tesla's business case was to drive down the cost of each unit, sell far more of them, and add solar and grid services on top.

How it Works

A Powerwall is wired between the utility meter and the home's breaker panel. Solar charges it by day, the grid tops it off when rates are low, and the battery gives that power back when the home needs it or the grid goes dark. The biggest leap from one generation to the next came in the hardware. Powerwall 1 in 2015 gave you 6.4 kWh of usable storage. Powerwall 2 in 2016 doubled that to 13.5 kWh and added a built-in inverter rated at 5 kW. Powerwall 3 in 2023 kept the storage the same but poured all its gains into raw power.

That jump in power is the whole reason one unit is now enough. Powerwall 2 delivered 5 kW, while Powerwall 3 delivers up to 11.5 kW, can kick on heavy motors rated up to 185 amps, and accepts up to 20 kW of solar across six inputs. Elon Musk wrote: "What matters most about Powerwall 3 is that it can handle peak power of ~30kW, which is enough to handle dryers & air-conditioners. This means that a single Powerwall is now enough for most homes." Building the inverter into the battery also makes it easier to install.

The Economics of the Powerwall

The first Powerwall launched at $3,000 for the 7 kWh daily model, which gave you 6.4 kWh of usable storage, and $3,500 for the 10 kWh backup version, both before installation. The long-run math rests on a 10-year warranty that promises the battery still holds 70 percent of its capacity after a decade. For a household, the payback is the peak-rate power you never have to buy, the solar you store instead of selling back cheap, and the power that stays on through an outage. For Tesla, every install builds a lasting relationship across solar and grid services.

Current Status of Powerwall

The Powerwall is the face of a fast-growing storage business. Tesla does not break out Powerwall-only figures, so the clearest measure is total Tesla energy storage, which counts the utility-scale Megapack alongside the home battery.

Storage deployments climbed from 6.5 gigawatt-hours in 2022 to 46.7 in 2025. Powerwall installs rose too.

Total Powerwall installs roughly doubled in about two years, passing 1 million worldwide in September 2025. Tesla's energy generation and storage segment, which includes Powerwall, brought in $12.8 billion of revenue in 2025.

What Comes Next

The next chapter is about the network Powerwalls form together. Powerwall 3 scales up: stack several units and Expansion packs, and a home can reach up to 44 kW and 94.5 kWh of storage. Thousands of these batteries can be enrolled in virtual power plants, where a utility calls on home batteries all at once to steady the grid during a demand spike. As Elon noted when the team hit its milestones, a Powerwall gives a home "guaranteed continuous power during utility blackouts or brownouts," and adding solar lets a household "operate off grid."

The Bottom Line

The Powerwall changed how a home uses the grid: it stores the home's own solar power, keeps the lights on in a blackout, and can send power back when the grid runs short. Tesla's fourth-quarter 2025 update said Powerwalls had supported more than 89,000 virtual power plant events.