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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).

Solar panel and battery

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?

sleek solar panels

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?

Constantine with a battery

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.

Power the average UK home for a day

Based on the UK average electricity usage of a typical home of ~3,900 kWh/year or ~10.7 kWh/day (Ofgem Typical Domestic Consumption Values, 2024).


Tesla Powerwall 3 Expansion Pack provides 13.5 kWh of storage which is more than the 10.7 kWh which is enough to power a typical home for a day.


Add up to 65 miles of EV range

Based on average EV efficiency of 4.8 miles per kWh (source: ZapMap, EV Database). Actual range will vary depending on vehicle model, driving conditions and efficiency.

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