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Tesla Powerwall 3: One Year On
As the third generation of Tesla Powerwall reaches its first year of UK installations, CCL Technical Manager, Kevin Gospage, caught up with Gary Stirling, UK & Ireland Country Manager – Residential Energy at Tesla Energy, to explore how Powerwall’s upgrades are transforming installations and performance. From higher power to easier installation and smarter integration, they discussed how Powerwall 3 is helping you work more efficiently on site and delivering even greater benefits for homeowners.
“Essentially what we’ve done is massively upgrade the power output,” Gary says. “We’ve made it significantly easier to install and we’ve also integrated our solar inverter. We’ve ramped up how flexible it can be and brought as much as we can into a single box.”
Caption: In the video interview, CCL’s Kevin Gospage joins Gary Stirling from Tesla Energy to explore Tesla home battery storage, including the features and benefits of the latest Powerwall generation for installers and homeowners.
A New Generation of Powerwall
Caption: Powerwall 3 UK, designed for straightforward installation.
Launched in the UK in 2024, Powerwall 3 is a compact home battery that stores energy generated by solar and from the grid, allowing installations with or without solar. With customisable power modes, homeowners can optimise their stored energy for outage protection, energy independence or savings on their electricity bills.
Tesla Powerwall Upgrade
This latest model replaces Powerwall 2 with upgrades across the board, from installation flexibility to software intelligence and performance, resulting in three headline gains:
- Increased output power
- Simplified installation
- Integrated solar inverter
Integrated Solar Inverter
One of the biggest changes to Powerwall is the built-in inverter. By including a hybrid inverter within the unit, Tesla has made installation even easier and more cost-effective.
Maximising Yield
The built-in inverter enables DC oversizing of up to 20kW to maximise system yield as light levels change throughout the day and year. It supports string lengths of between two and fifteen solar modules, and includes three MPPTs to mitigate losses from complex roof designs or partial shading.
“It gives you tons of flexibility in terms of how you design,” comments Gary.
One Product Fits All
Rather than multiple variants, there’s just one Powerwall unit for you to purchase with a single SKU. When it comes to commissioning on site, you simply select one of the power ratings, from 3.68kW to 11.04kW, along with the DNO permissions and power approval, and Powerwall will set itself to meet those parameters.
For export limitation, you free-type the limit given by the DNO and Powerwall will take that into account when it manages the flow of energy within the home and to the grid.
Upgradable Capacity
If the customer requires a greater power output at a later date, it can be changed remotely once approved by the DNO.
Scalable Storage for Growing Needs
Powerwall includes 13.5kWh of usable storage, which is enough to power most homes’ daily demand. For larger systems, there’s no longer a need to parallel-connect more units to the system, and no longer a requirement to get DNO approval. The new DC expansion packs allow you to add additional 13.5kWh storage capacity via a harness that plugs into the side of the system, with an installation time of under 30 minutes per expansion pack.
Caption: With the Tesla Powerwall DC expansion pack, you can have four Powerwall units on a single site and get 44kW of power with 54kWh of capacity.
You can also fit up to three expansion packs to give a total storage capacity of 94.5kWh. Depending on space constraints on site and how the homeowner wants it to look, they can be stacked front-to-back or side-by-side.
DC-Coupled Storage
Since the Tesla solar battery is now DC-coupled, in addition to simplifying DNO permissions, your customers will see even greater efficiencies through lower conversion losses as the Powerwall charges directly from the PV.
Built for the British Weather
Designed and built for indoor or outdoor installation, Powerwall is IP67-rated and floodproof up to 60cm. The units are thermally managed from –20°C to 50°C through a combination of heating and cooling, to ensure that the battery operates within its optimal temperature range, even in extreme conditions.
Backup Power and the Gateway
Using the familiar Tesla Backup Gateway, you can configure Powerwall 3 for whole-home backup or isolated essential loads such as lighting, fridge or boiler. Most customers choose whole-home backup, but the option of wiring non-essential loads avoids draining the battery with high-demand items like EV chargers or hot tubs during a power cut.
The Gateway also includes free space at the bottom of the unit with a DIN rail, which is useful for other system components such as an EV charger. And since it’s the same Gateway, customers who want to upgrade from Powerwall 2 to Powerwall 3 benefit from a straightforward swap with the majority of the cabling kept the same.
Storm Watch – Automated Energy Security
Available in the UK and optional via the Tesla app, Storm Watch ensures that Powerwall has enough stored energy to power the home in the event of a grid outage. The system monitors weather data and syncs with local forecasts from the UK Met Office to proactively prepare for storms. It activates automatically during amber or red weather warnings and prioritises charging to the maximum capacity, ready to provide backup power if required.
Unique Packaging – and Tesla Want It Back
One of the standout items for the CCL team when the first stock of Powerwalls arrived at our Glasgow and Leicester warehouses was the new packaging. Made from a durable plastic, the “clamshell” protects the unit in transit and is fully recyclable. Reflecting Tesla’s sustainability goals, it’s designed to be returned and reused.
Powerwall Dolly
Powerwall Dolly is purpose-built for Tesla Powerwall installation. The transportation and lifting tool includes hydraulic disc brakes and slide rails for rough terrain and descending stairs. It interfaces directly with Powerwall and uses a battery-powered drill to drive the lifting mechanism, allowing you to manoeuvre and position Powerwall on site for an easy and safe installation.
Smart Control via the Tesla App
The app was designed to bring the entire Tesla ecosystem into one place, so homeowners can see real-time solar generation and monitor and control battery capacity, EV charging and home loads. Gary notes:
“You can see exactly, at a glance, every way you’re using energy within your home.”
Taking Away the Guesswork
Powerwall also includes Opticaster, an intelligent software tool that keeps the home running at the lowest cost possible. By taking the homeowner’s usage patterns into account, as well as weather forecasts and the user’s energy tariff, it makes smart decisions to run the home, adjusting charging and discharging to get the very best out of the system.
A Warranty to Support Over a Million Powerwalls
“We have just built our one millionth Powerwall … you get to that number by having reliable products and our warranty backs that up,” comments Gary.
Tesla’s warranty provides 10 years’ cover with unlimited charge cycles. Powerwall has 100% depth of discharge and, if Powerwall drops below 80% energy retention, Tesla will replace it.
For you, as an installer, Tesla manages the RMA process directly so, in the rare case of a fault, they will handle the return of the units to be recycled and supply the new parts. Importantly, the warranty covers both parts and labour. Tesla pays engineers to return to site, so you’re not left out of pocket.
Supporting Installers
Tesla is determined that installers have the knowledge and tools to deliver high-quality installations from day one. To install Powerwall, your company must be Tesla-certified and that brings with it a number of benefits:
- Online training via the partner portal
- In-person roadshows and events
- On-site field trainer support
- A dedicated UK account team
Final Thoughts
Kevin summarises the latest generation of Tesla home battery storage: “With its integrated inverter, flexible expansion, extreme weather resilience and smart software, Powerwall 3 is a solid choice for any installer looking to provide a premium solution.” Powerwall offers homeowners greater energy independence and gives you, the installer, a simpler and faster installation.