Battery Storage Knowledge Bank

Tesla Powerwall 3 - Everything you need to know

Tesla Powerwall 3 price Spirit Energy

Tesla Powerwall 3 at a glance

Tesla’s latest battery product has now been announced, whilst not all the information has been released to the public yet and we aren’t allowed to share more, here’s what we can say about Tesla’s latest way to reduce your climate impact, through storage of solar and off-peak charging.

Specifications

Usable capacity: 13.5kWh
Continuous power output: 11.5kW
Round-trip efficiency: 97%
Monitoring: Tesla app
Warranty: 10 years
Mounting: Wall- or floor-mounted
Location: Indoor or outdoor installation - Flood and dust resistant
Weather resistance: -20°C - 50°C
Dimensions: H 1,098.6mm x W 609.6mm x D 193.04mm
Weight: 130.18kg
MPPT strings: 6
Scalability: Up to 40.5kWh max addition per unit

Main Features

-Continuous output 11.5kW

-13.5kWh capacity

-Flood and dust resistant

-Integrated hybrid inverter with 6 MPPT strings

 

How much does the Tesla Powerwall 3 cost?

The price of the Powerwall 3 has not been announced yet, however, given the calibre of the integrated inverter, along with it being at the start of its product cycle, we’d expect the price to be between £12,000 - £18,000 inc. VAT fully installed, compared to the Powerwall 2 which we currently price around £9,000 - £9,500 inc. VAT fully installed.

Powerwall 3 vs. Powerwall 2

Tesla Powerwall 2 current price £8,500 - £9,500 inc. VAT fully installed.

Takeaways

-Price not announced, we predict £12,000 - £18,000 inc. VAT fully installed

 

Does the Tesla Powerwall 3 have a hybrid inverter?

The most exciting new feature Tesla have announced for the Powerwall 3 is the integrated hybrid inverter. There are two key reasons why this is important, 6 MPPT strings and increased DNO acceptance likelihood. Here’s an outline of each.

6 MPPT strings

Essentially what this means for the user is that they potentially will get better shade mitigation than any other domestic inverter, whilst being able to install more solar panels at once than any other domestic inverter.

Further information

You can have 6 independent orientations or shade areas, with a maximum of 6 strings. This means that at 11.5kW, with 20% clipping, it’s possible to install 30-35 panels (panel dependent), with string sizes of 5-6 per string, with each string independently tracked.

DNO acceptance likelihood

A DNO (District Network Operator) application is what you must do when asking for to connect more than 3.68kW to the grid.

Because the inverter combines the solar inverter and the battery inverter, the potential output of the system will decrease, which increases DNO acceptance likelihood.

Whilst it may be unlikely to get approved for 11.5kW output by your DNO, Tesla have a track record of certifying their batteries and inverters to be able to support lower outputs, meaning that you may be able to downclock this inverter to meet your DNO permission. See Powerwall 2 certification at both 3.68kW and 5kW, unlike competition.

Powerwall 3 vs. Powerwall 2

Tesla Powerwall 2 does not have any hybrid inverter, only a separate ‘Gateway’ battery inverter.

Takeaways

Superior shade mitigation

Higher DNO acceptance likelihood

Tesla Powerwall 3 installation Spirit Energy

What chemistry does the Tesla Powerwall 3 use?

Nothing has been officially confirmed yet regarding the battery chemistry of the Powerwall 3. Most in the market use LFP (Lithium Ferro Phosphate), however, Tesla often use LNMC (Lithium Manganese Cobalt), citing its higher power density and lower weight. The weight of the Powerwall 3 would indicate the same chemistry, LNMC, coming in at just 130.18kg at 13.5kWh.

The GivEnergy All in One, a 13.5kWh battery using LFP, comes in at a whopping 173kg. Meaning, even with an integrated inverter, the Powerwall 3 will be almost as energy dense as the Powerwall 2, which uses LNMC.

Powerwall 3 vs. Powerwall 2

Powerwall 2 uses LNMC

Takeaways

Powerwall 3 likely uses LNMC (not confirmed)

 

Round trip efficiency

The Powerwall 3 reportedly has industry leading round-trip efficiency at 97.5%. This is the amount of power put in from solar, minus the amount lost before exporting to the grid. What this means for you is that this system will be able to retain more power than any other major battery in the UK market. Tesla likely achieved this by being able to control the inverter and battery system completely, rather than having a 3rd party inverter.

Interestingly, this is the same efficiency as the Powerwall+, which was never released in the UK, only the US market. The Powerwall+ also had an integrated solar inverter, but with only 4 MPPT solar strings.

Takeaways

Able to retain more power than any other major battery in the UK market

Powerwall 3 vs. Powerwall 2

Powerwall 2 has a round-trip efficiency of >90%

Release date

The Powerwall 3 is set to come out in the US in 2024. This launch date will be later in the UK. You won’t be able to add Powerwall 3 systems to your current Powerwall 2 set up, or vice versa.

Off-peak charging

Similarly to the Powerwall 2, the Powerwall 3 will allow users to off-peak charge, allowing them to take advantage of time-of-use tariffs. This means that Powerwall will offer two different ways to use it, either self-powered, or time based control:

 
Mode Backup reserve Solar self usage %  Savings  Who should do this?
Self-powered Configurable (0-100%) Great! OK "I want to minimise my carbon footprint"
Time-based control Configurable (0-100%) OK Great! "I have a ToU tariff and want to maximise my savings"

You don’t even need a solar system to benefit from time-of-use charge and discharge. That said, the best savings will be realised through a combination of solar self-consumption and ToU charging and discharging.

Backup

Tesla Powerwall 3 enables you to continue providing power to your property during power cuts. It also allows your solar PV system to keep running in a power cut.

You can specify a custom reserve percentage (e.g. 30%) and the system will always keep that percentage of the capacity in reserve for a power cut. 

At 30% capacity (4kWh), the Powerwall should power a standard home for around 4 hours, whilst allowing you to keep the TV, fridge, lights and WiFi on.

Typical loads are as follows:

Kitchen

  • fridge / freezer: 500W;
  • kettle: 3,000W;
  • oven: 3,650W;
  • induction hob: 1,500W;

Office and entertainment

  • laptop: 50W;
  • TV: 80W;

Lighting

  • average lighting load 500W (2,500W all LED lights blazing for a typical 4 – 5 bed house);

Laundry / dishwasher

  • dishwasher: 1,250W;
  • washing machine: 500W;
  • electric clothes dryer: 4,000W.

Battery storage for solar panels: summary page

Interested about finding out about other battery systems?

Read our summary page on battery storage for solar panels.