Tesla
Tesla Powerwall 3
B4.4 PW3
13.5kWh battery with a built-in solar inverter and class-leading continuous output, including whole-home backup.
13.5kWh
Usable capacity
Joint best of 3 we compare
11.5kW
Power output
Best of 3 we compare
54kWh
Max with expansion
LFP
Chemistry
10yrs
Warranty
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Our verdict
Powerwall 3 folds the solar inverter into the battery and offers class-leading continuous power, making it excellent for backup and larger homes, at a premium price.
Good
- Very high power output
- Integrated solar inverter
- Strong app and backup
Watch out
- Premium price
- Less modular flexibility
Will it pay for itself?
21.9 years to pay back a £7,500 Tesla Powerwall 3 from £342 a year of off-peak savings. That's 11.9 years after the warranty ends.
A typical home using 9.3 kWh a day, 58% of it at
peak. Day rate 26.32p, Intelligent Octopus Go off-peak 8p, 89% round trip. Hardware only, so installation adds to the payback time. Rates
checked 20 September 2026. Try your own numbers
Specifications
| Usable capacity | 13.5 kWh |
|---|---|
| Power output | 11.5 kW |
| Max with expansion | 54 kWh |
| Chemistry | LFP |
| Whole-home backup | Yes |
| Warranty | 10 yrs |