- American company, part of Tesla's Energy division, selling home batteries since the original Powerwall launched in 2015
- Powerwall 3, the current generation, adds a built-in solar inverter and switches to LFP (lithium iron phosphate) cells
- Each unit stores around 13.5 kWh of usable capacity, with multiple units combinable for larger whole-home systems
- Installed exclusively through Tesla-certified installers rather than sold as a DIY unit
- Available in numerous markets, including the UK, since Powerwall 3's launch in June 2024, backed by a 10-year warranty
Independent coverage
This page reflects our own independent assessment of Tesla Powerwall, not a sponsored placement. If we later add affiliate links to Tesla's site, any commission we might earn does not change what we say about the brand here.
Who is Tesla
Tesla, Inc. is the US electric vehicle and energy company founded in 2003 and now headquartered in Austin, Texas. Its home batteries sit within Tesla Energy, the division that also builds solar products and large-scale grid storage.
Tesla launched the original Powerwall in 2015 and followed it with Powerwall 2 in 2016. In 2024, the company unveiled a substantially redesigned Powerwall 3, with a new battery chemistry and a built-in solar inverter. Tesla confirmed Powerwall 3 as available to order in several markets, including the UK, from June 2024. A network of Tesla-certified installers sells and fits it exclusively, rather than Tesla’s own install teams.
The Tesla Powerwall range
Tesla rates both Powerwall 2 and Powerwall 3 at around 13.5 kWh of usable capacity per unit. Installers can scale up Powerwall 3 with Tesla’s own Expansion units. Tesla’s official installation documentation sets a maximum of four Powerwall 3 units (one Leader plus up to three Followers), plus up to three Expansion units attached to the Leader. That’s seven units in total, for a maximum system size of 94.5 kWh. The actual size your installer fits still depends on your property and local grid connection. Treat that 94.5 kWh figure as the engineering ceiling, rather than a typical install.
The two generations differ more on power and integration than on raw capacity. Powerwall 2 is AC-coupled, meaning it sits alongside a separate solar inverter. Tesla rates it at around 5 kW continuous output and roughly 7 kW at peak. Powerwall 3, by contrast, is a DC-coupled, all-in-one unit with its own built-in hybrid inverter. Tesla’s headline continuous power figure for it is 11.5 kW in its US specification.
In markets with a phased low-voltage grid, such as the UK, Tesla’s own datasheet rates the built-in inverter’s continuous single-phase output as selectable between 3.68 kW and 11.04 kW. This isn’t a weaker unit. It’s a setting the installer configures to match what your local grid operator has approved for your specific connection. In the UK, this approval sits with your Distribution Network Operator (DNO). Properties above the standard 3.68 kW per-phase threshold need DNO permission for a higher output. Other markets apply similar grid-connection approval steps under their own rules.
Both generations also carry a 10-year warranty, with a stated guarantee of at least 70% capacity retention at the end of that period. Most independent summaries describe the cycle allowance within the warranty as uncapped. That said, it’s worth checking the specific warranty document for your market, since the exact wording can vary.
~13.5 kWh
usable capacity per unit on both Powerwall 2 and Powerwall 3
3.68-11.04 kW
Powerwall 3's selectable continuous output, set by your local grid operator's approved connection (DNO in the UK)
10 yrs
warranty, with a stated 70% capacity retention guarantee
Key technology behind Tesla Powerwall
The clearest technical difference between the two current generations is chemistry. Powerwall 3 uses lithium iron phosphate (LFP) cells. This is a shift away from the nickel manganese cobalt (NMC) cells used in Powerwall 2, developed with Panasonic. Tesla itself doesn’t dwell on the Powerwall 2 chemistry in its own marketing. However, industry trade press covering Tesla’s 2021-22 Powerwall 2 fire recall confirmed it as NMC at the time. LFP is generally a more thermally stable chemistry, though it has somewhat lower energy density. As a result, it typically needs more cell material to deliver the same stated capacity.
On round-trip efficiency, the two generations are closer than headline marketing figures suggest. Tesla’s own datasheets state a 90% AC-to-battery-to-AC round-trip efficiency for Powerwall 2. For Powerwall 3, the figure is an 89% solar-to-battery-to-grid round-trip efficiency. Tesla measures both figures under the same conditions (25°C, 3.3 kW charge/discharge, beginning of life). The higher 96-97% figures sometimes quoted for Powerwall 3 aren’t round-trip numbers at all. They describe its separate “solar to grid” efficiency: the direct path solar power takes straight through its built-in inverter without passing through the battery. A DC-coupled design like Powerwall 3 handles this path with one less conversion step than an AC-coupled Powerwall 2.
Powerwall 3’s other headline change is its built-in hybrid inverter, with several MPPT solar inputs. This lets a single unit connect directly to solar panels, rather than needing a separate inverter the way Powerwall 2 and AC-coupled rivals do. In practice, this can simplify what’s fitted inside an installation. However, it also makes Powerwall 3 more of an all-in-one commitment than a drop-in addition to an arbitrary existing inverter.
The Tesla app monitors both generations. It shows live charge, generation and consumption data, and lets you choose modes such as self-powered, backup-only, or time-based control for exporting during higher-price periods. Tesla’s Storm Watch feature can automatically charge the battery ahead of forecast severe weather. A separate piece of hardware, the Backup Gateway, manages the switch to backup power during a cut.
Strengths and limitations
As with any brand, Tesla’s own marketing understandably leads with its strengths. Here is a more balanced picture.
Strengths
- Strong brand recognition and one of the largest installed bases of any home battery worldwide, giving it an unusually long track record for the sector
- Powerwall 3's built-in hybrid inverter and LFP chemistry can simplify installation compared with separate battery-plus-inverter combinations
- Tesla's own app and Storm Watch feature give integrated monitoring and automatic pre-storm charging without juggling third-party apps
- A straightforward 10-year warranty with a stated 70% capacity retention guarantee and, on most accounts, no cycle cap within that period
Worth checking before you buy
- Not a DIY product; professional installation through a Tesla-certified installer is required, which adds cost and limits who can fit it
- Tesla does not publish a fixed retail price list in most markets, so getting a comparable figure means requesting installer quotes rather than reading one number off Tesla's site
- Powerwall 3's continuous power output is a configurable setting rather than one fixed number: Tesla's datasheet for markets with phased low-voltage grids, such as the UK, allows 3.68 to 11.04 kW, with the actual figure capped by what your local grid operator approves for your connection rather than by the unit itself
- We have not independently tested Tesla's pricing, support or installation process ourselves
Where Tesla Powerwall fits the market
Tesla Powerwall is a whole-home, professionally installed battery system, not a plug-in or DIY product. Globally, that puts it alongside brands such as GivEnergy, Sunsynk, Alpha ESS and Fox ESS. These sit apart from the plug-in, socket-connected batteries covered elsewhere on this site.
Within that whole-house segment, Tesla’s main selling points tend to be brand recognition and its own tightly integrated app. On Powerwall 3, there’s also the simplicity of a single all-in-one unit. The trade-off is that you’re committing to Tesla’s own hardware, software and certified-installer network, rather than mixing and matching inverter and battery brands. If you’re still working out what capacity your home actually needs, our capacity guide and free calculator cover that ground independently of any one manufacturer. Use them before comparing whole-house brands like this one.
Common questions about Tesla Powerwall
What is Tesla Powerwall?
Tesla Powerwall is a whole-home rechargeable battery system that stores solar power, or cheap off-peak grid electricity, for use later in the day or during a power cut. It's a fixed, professionally fitted unit rather than a portable or plug-in battery.
Is Tesla Powerwall worth it?
That depends on your household's usage, any solar setup, and what you'd actually pay for installation, which Tesla doesn't fix at one UK price. For most households, the main value comes from shifting self-generated solar or cheap overnight electricity into peak-rate hours, plus backup power during outages. It's worth running your own numbers against your actual bills and roof size, rather than relying on brand reputation alone.
Can I install a Tesla Powerwall myself?
No. Tesla does not sell Powerwall as a DIY product. Tesla-certified installers install it exclusively. The work also involves electrical installation, which only a qualified, registered installer should carry out in any case.
How much does a Tesla Powerwall cost?
Tesla does not publish one fixed retail price. The final cost depends on your market, the installer, any Backup Gateway and additional hardware, and your property's wiring. Get quotes from Tesla-certified installers in your area for an accurate figure. Then use our calculator to work out the capacity you actually need before comparing costs.
Which markets is Tesla Powerwall available in?
Tesla sells Powerwall in numerous markets worldwide. It confirmed Powerwall 3 as available to UK customers from June 2024. UK customers order it through Tesla's own site, and a Tesla-certified installer fits it. Availability and launch timing vary by country.
Can Tesla Powerwall provide backup power during a blackout?
Yes, when fitted with Tesla's Backup Gateway hardware, Powerwall can automatically switch to backup power during a grid outage. How much of the home it can power, and for how long, depends on the number of units installed. It also depends on what's drawing power at the time.
Not sure if a whole-home battery like this suits your property?
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