Powerwall 3 just got even more powerful
Introducing Expansion Packs - extra oomph for your battery
If you've already got a Tesla Powerwall 3, or you’re looking to get one, you can now add Expansion Packs to boost the amount of energy your system can store - without needing a whole second unit. That means double the power saved for when the sun goes down (or the grid goes dark).
We're a Tesla Powerwall Premium Certified Installer, and we’re now offering Expansion Packs:
If you’re looking to get solar and a battery with us
If you’re after a battery system on its own
If you’ve already had solar installed and want to add a Powerwall 3
If you've already got your Powerwall 3 fitted by us and want to add more storage
Just a heads up - if your Powerwall 3 was installed by someone else, we can’t add an Expansion Pack for you.
What is an Expansion Pack?
Think of it as a battery booster.
It’s a Powerwall 3 without the bits you don’t need twice (like the inverter). It connects directly to your current Powerwall 3 and each additional pack gives you 13.5 kWh of extra storage (that’s the same capacity as the Powerwall 3). So, with an Expansion Pack, you can bank more of your cleaner, cheaper solar energy - ready for when you need it.
Expansion Packs have the same height and width as a standard Powerwall 3, but are a little slimmer in depth, so they slot in neatly next to your existing unit. Up to three packs can be installed alongside a Powerwall 3.
Why add more storage?
Do I need one?
The Powerwall 3 already provides 13.5 kWh worth of storage which is pretty impressive. But you might want to consider more, if:
You regularly see your Powerwall 3 hit 100% before the day’s solar has ended
You’re planning to add a heat pump or EV soon
You’d like to store more off-peak electricity from the grid
You want a bigger backup during power cuts
You can check your battery’s usage in the Tesla app or give us a call on 0808 196 6842 and we’ll help you think it through.
13.5 kWh goes a long way
With 13.5 kWh of extra storage you could power the average UK home for a full day or add up to 65 miles of EV range. See our workings
How much does it cost?
£3,773
If you’re installing an Expansion Pack alongside a Powerwall 3 during the same installation.
£5,409
If you’re installing the Expansion Pack to an existing Powerwall 3 battery.
Ready to expand?
If you don’t currently have solar panels or a battery and you’re looking to place an order, you can get started here.
If you’ve got solar panels or a Powerwall 3 already, select the battery only option below.
If you’d like to chat through your options, give our specialists a call on 0808 196 6842.
Frequently asked questions
An Expansion Pack is just the battery - it connects to a Powerwall 3 and shares the same inverter and control system. It’s a more cost-effective way to add storage.
They both have 13.5 kWh storage capacity.
It’s the same height and width as a Powerwall 3 - just a bit slimmer in depth. Designed to sit neatly alongside the existing unit
Nope - it needs to be installed by a Tesla Certified Installer. (That’s us.)
Check the Tesla app. If your battery often hits 100% while the sun’s still shining, or you’d like to store more off-peak electricity, an Expansion Pack could be a smart move.
If you're adding a heat pump or an EV charger, it’s worth checking if your battery can keep up. A Powerwall 3 Expansion Pack gives you extra storage to:
Charge your EV using solar or off-peak energy
Run your heat pump without relying on peak grid prices
Future-proof your setup for smarter savings
No, we’re only installing Expansion Packs to Powerwall 3 systems that we’ve installed ourselves.
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You'll have the option to pay monthly with a fixed-term loan, or pay in full after installation. We'll ask you to pay a non-refundable deposit of £500 when you sign your installation agreement.
Your solar and battery system could pay for itself in 9-13 years
According to the Energy Saving Trust, a solar system can pay back its cost in 9–13 years, depending on where you live and how much time you spend at home.
Payback periods are affected by factors such as your household electricity use, your roof size and orientation, and whether your system includes a battery.
After a free consultation, our solar specialists can provide a tailored estimate of your potential savings and payback period based on your home and system design.
Solar systems increase the value of your home
Analysis by the Department of Land Economy at the University of Cambridge suggests a 16% value uplift for new-build homes with enough solar and battery storage to eliminate energy bills. A further study of over five million existing properties indicates a 2-3% value increase for existing homes with solar panels or heat pumps (versus like-for-like gas-heated homes). According to the Sustainable Markets Initiative: Sustainable Markets Initiative: Cleantech Homes report, 2024.
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