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What Could the UK Version of Tesla's Powerwall 3 Look Like?

Luke Pemberton · 14 Jun 2024

This is the only photo that we have of the Powerwall 3, taken when one of our technicians visited Tesla at the ExCel in London. 

Tesla Powerwall 3 is forecasted to be coming to the UK to replace Tesla’s current Powerwall 2 in the next 6 – 12 months, and from the little of what we know so far from the US product, it will have the same 13.5kWh storage capacity as well as similar technological features but with a new, game-changing integrated hybrid inverter. 

What will the new inverter mean for UK customers? 

Though there are currently plenty of hybrid inverter + battery solutions on the market in the UK, none share as impressive specifications as the ones Tesla have claimed for the upcoming Powerwall 3. With a quoted 11.5kW maximum power, it will be the highest capacity domestic hybrid inverter in the UK. 

There are higher output, specialist hybrid inverters on the market. For more information on high power specialist inverters, please see here about our Victron system. 
What this translates to for consumers are potential charging times of as little as 1 hour 12 minutes (assuming the battery unit can take the full rate of charge from the inverter). Additionally, customers will be able to fit as many as 34 panels on this one inverter, further aided by the 6 MPPT strings this new inverter claims. 
Ground breaking consumer technology.
Faster charging/discharging speeds.
More panels on a single inverter. 

Will this actually make a difference to the average UK household? 

In the Spirit Energy Offices in Reading, the technical design team has lately been buzzing with discussion on whether the Powerwall 3 will be as enticing to ordinary consumers as it is to our highly technical and geeky team. 
Undoubtedly, the inverter is a huge step forward, and is a great sign for the future of renewable technology, but is it overkill? Will the average UK household actually be able to take advantage of the whopping 11.5kW? 

It’s hard to say, and there’s a huge number of factors it will depend upon, but here are the facts: 
Most houses will never be able to fit enough panels to fill this whole inverter capacity, not unless panel output per sqm increases 3-6x, which is a huge ask in itself. 
Most of our domestic solar panel installations ranged from 8 - 16 panels last year, obviously with a few exceptions. Not many roofs in the UK can fit more than 16 panels, which works out to be ~7kW.
The other potential restriction to 11.5kW is that the DNO may not allow for the full capacity to be used. The maximum that you can install on a single-phase supply is 17kW, however, most households would be lucky to be given such a large quote by their local DNO. More often than not, the DNO starts to implement restrictions when we apply for anything above 8kW.  

A solution Tesla could implement to mitigate this issue, and that they have previously implemented, is rating the new Powerwall 3 at multiple different outputs. The Powerwall 2 is rated at two different outputs, 3.68kW, and its full 5kW. We expect that the Powerwall 3 inverter will be modular, meaning that if you do get restricted you can still use the product, just at a lower AC- output. 
So perhaps this will be the beauty of the upgraded inverter. Tesla could release it with different ratings, like the below, for example: 
3.68kW - for heavily DNO constrained systems. 
5kW - for medium sized solar systems, possibly with DNO constraints. 
8kW - for large sized solar systems with minimal DNO constraints. 
11.5kW - for solar and battery systems capable of utilizing the Powerwall 3’s full potential. 

We look forward to the announcement of the Powerwall 3 in the UK, and hope to see it sooner rather than later. The Tesla Powerwall 3 has taken the US battery market by storm and it seems to be somewhat the perfect product for the US market. Let’s hope that Tesla does a good job of adapting it to the nuances of the UK market and hopefully it’ll fly off the shelves as the Powerwall 2 has been doing for over 6 years now. 

Topics: Battery storage, Tesla Powerwall