The Tesla Powerwall has long been a leading choice in the UK domestic battery market. Tesla is a trusted brand in all things electric, from their electric cars to their solar batteries, and more recently the development of solar tiles (yet to be available on the UK market) and an application to Ofgem to become a UK energy supplier.
Tesla’s most recent contribution to the solar battery market is the Powerwall 3, which takes things to the next level. With a sleek, modern design, upgraded power capabilities and a built-in hybrid solar inverter, the Powerwall 3 is the latest in home energy storage innovation.
At SolarTherm UK, we’re Tesla-approved installers, offering expert installation for the Powerwall 3. Here’s everything you need to know about its system specifications, performance and warranty.
Capacity and Expandability
Both the Powerwall 2 and Powerwall 3 store 13.5kWh per unit, which is plenty for most UK households to cover daily energy needs or a short power outage. The Powerwall 3 is expandable with an additional 3 units (DC-coupled) giving a total of 54kWh. The Powerwall 2 supports up to 10 units at 135kWh, most UK households average 8-12kWh per day so 135kWh is a bit excessive for UK households.
The modular approach makes it easier to scale up and upgrade your system as your energy needs grow, whether that’s as you add an EV, heat pump or your lifestyle changes.
Performance and Efficiency
The Powerwall 3 significantly improves power output, delivering up to 11.5kW continuous power, more than double the Powerwall 2’s 5-7.2kW, meaning your home can run multiple appliances simultaneously, even during peak energy times.
Efficiency is slightly higher too at 90& on the Powerwall 3 compared to 89% on the Powerwall 2. Both modules allow 100% depth of discharge allowing you to use the battery’s full capacity without shortening the lifespan.
Warranty and Reliability
Both the Powerwall 2 and Powerwall 3 come with a 10-year warranty, guaranteeing up to 70% capacity retention after 10 years. Tesla further stands out from the crowd with unlimited cycle coverage, meaning you can fully charge and discharge your battery as often as needed without it affecting the warranty. This added benefit gives homeowners maximum flexibility and confidence in the long-term performance of the Powerwall battery.
Tesla Powerwall 3 Cost
To install a Tesla Powerwall 3 with SolarTherm UK you would be looking at prices starting around £7500, however when installed as part of your whole solar PV system prices will be reduced.
Not all installations are the same, at SolarTherm UK we design your system bespoke to your property and usage.
Tesla Powerwall 2 vs Powerwall 3
| Feature | Tesla Powerwall 3 | Tesla Powerwall 2 |
| Usable Capacity | 13.5 kWh | 13.5 kWh |
| Max Units Installable | Up to 4 (54 kWh) | Up to 10 (135 kWh) |
| Round-trip Efficiency | 90% | 89% |
| Depth of Discharge | 100% | 100% |
| Continuous Power Output | 3.68–11.5 kW | 5–7.2 kW |
| AC/DC Coupled | AC or DC (built-in hybrid solar inverter) | AC only |
Key differences: the biggest upgrade with the Powerwall 3 is the all-in-one hybrid system, featuring the built in solar inverter, eliminating the need for a separate inverter. Installation is simpler and install costs are reduced. The Powerwall 3 is also compatible with an existing solar array and microinverters, making it the perfect option for a amooth and hassle-free system upgrade.
Why Choose the Tesla Powerwall 3?
- Integrated hybrid design – built in solar inverter simplifies installation and reduces costs.
- High performance – up to 11.5kW continuous power, double the previous generation of Powerwall.
- Expandable – add additional units for more storage capability up to three units for a total of 54kWh of storage.
- Efficiency and reliability – 90% efficiency, 100% depth of discharge, 10-year warranty and unlimited cycle coverage.
- Seamless solar integration – compatible with existing solar arrays and microinverters.
The Powerwall 3 is a future-proof solution for homeowners looking to increase energy independence, reduce grid reliance and integrate renewable energy seamlessly. The Powerwall 3 is EPS (Emergency Power Supply) ready and can be set up to power your home in the event of a grid power failure.
Next Steps for Your Battery Storage Journey
If you’re considering battery storage for your home, you need to consider the following:
- What size battery do you need
- Whether you need battery storage without solar panels or higher storage than solar generation
- Pros and cons of battery storage
At SolarTherm UK, we provide bespoke battery quotes and flexible payment options, backed by MCS accreditation, Tesla certification and EPVS verified estimates.
Get a quote today for your Tesla Powerwall 3 upgrade and join thousands of happy SolarTherm UK customers enjoying smarter, cleaner energy and reduced energy bills.
At SolarTherm UK, we do the research so you don’t have to.
