Sigenergy vs Tesla Powerwall 3 is one of the most common battery comparisons people search for, and for good reason. They are two of the most capable home batteries in the UK, built on quite different ideas. We install both, so here is how they really compare.
The big difference in one sentence
The Powerwall 3 is one powerful 13.5 kWh box with a solar inverter built in. The SigenStor is a modular stack that lets you choose your capacity in smaller steps, with single and three phase options and its own EV charging.
Side by side
| Sigenergy SigenStor | Tesla Powerwall 3 | |
|---|---|---|
| Capacity | 5.2 kWh or 7.8 kWh usable modules, 1 to 6 per controller | 13.5 kWh usable per unit |
| Solar inverter | Built into the Energy Controller | Built in |
| Power output | Depends on the controller and number of modules | Up to 11.04 kW continuous in the UK, configurable |
| Phase | Single and three phase controllers | Single phase |
| Backup | Sigen Gateway, 0 ms load-side with the HomePro SP-F | Tesla Backup Gateway 2, whole-home backup |
| EV charging | Sigen 7 kW AC charger or DC module on the battery’s DC bus | Separate charger, such as a Tesla Wall Connector or zappi |
| App | mySigen with Sigen AI Mode | Tesla app |
| Warranty | 10 years, 70 percent retention or throughput limit | 10 years, 80 percent retention in the UK |
Figures come from each manufacturer’s published information and can change. We confirm exact specifications and warranty terms on every quote.
Capacity: one big block vs building blocks
If around 13.5 kWh is the right size for your home, the Powerwall 3 is a very neat answer: one unit, one install, a lot of power. If you need less, more, or want to grow over time, SigenStor is more flexible. You can start with one or two modules and add more later, up to six per controller, and each module has its own optimiser so new and old batteries can work together.
Power: who runs the kettle, oven and shower at once?
The Powerwall 3’s big selling point is power. Up to 11.04 kW of continuous output in the UK is enough to run most of a home’s heavy loads at the same time, and that matters in a power cut. SigenStor power scales with the controller and the number of modules, so a well designed stack can match the loads you care about, but a single small module will not. We size this carefully for both.
Backup in a power cut
Both need a gateway for backup: Tesla’s Backup Gateway 2, or a Sigen Gateway. Sigenergy specifies 0 ms load-side disruption with the HomePro SP-F when used with its own controller and battery. Tesla’s system also switches fast enough that most households will not notice. In both cases, what you can run is set by the inverter and battery, so we plan the backup circuits with you. See our Sigenergy Gateway guide.
Three phase homes
This is a clear win for Sigenergy. Its three phase controllers, some with up to four solar inputs, make it a natural fit for larger homes, farms and properties on a three phase supply. The Powerwall 3 is designed for single phase.
EV charging
Sigenergy keeps EV charging inside the same ecosystem, with a 7 kW AC charger and an optional DC module that connects to the battery’s DC bus. Tesla owners often pair a Powerwall with a Wall Connector, and many of our customers use a myenergi zappi to charge from spare solar. Vehicle to home is promised by Sigenergy’s DC module, but it depends on the car and software support. More in our Sigenergy EV charger guide.
Warranty and track record
Both carry a 10 year warranty. Tesla’s UK terms guarantee 80 percent capacity at 10 years, which beats Sigenergy’s 70 percent retention figure. Tesla also has a longer track record in home storage, while Sigenergy was founded in 2022. Sigenergy’s hardware is impressive, but if the strongest warranty and the longest history matter most to you, the Powerwall 3 has the edge here.
Our verdict
- Choose the Tesla Powerwall 3 if you have a single phase home, around 13.5 kWh suits you, and you want maximum power from one tidy unit with a strong warranty.
- Choose Sigenergy SigenStor if you are on three phase, want to size your battery precisely or expand later, want seamless backup, or want battery, solar and EV charging in one app.
Also weighing up GoodWe? Read Sigenergy vs GoodWe, and our Tesla Powerwall 3 page for more on the Powerwall.
Talk to an installer who fits both
We are MCS certified, use our own employed installation teams, and fit both Sigenergy and Tesla across Dorset, Hampshire and Wiltshire. We will survey your home and show you which one fits, with a fixed written quote. Visit our Sigenergy installer page or request a free quote.