The three Boxt Tesla offers, side by side
| Offer | What you get | Deposit | Monthly (48 months, 0%) | Total cost | Who qualifies |
|---|---|---|---|---|---|
| Renewable Energy Bundle | 8 solar panels + Powerwall 3, installed | £1,747 | £199 | £11,299 | Existing Tesla vehicle owners |
| Powerwall 3 finance | Powerwall 3 only, installed | £193 | £149 | ~£7,345 | Open, subject to credit approval |
| Powerwall 3 standalone (cash) | Powerwall 3 only, installed | n/a | n/a | £7,499 | Open |
All three routes end with you owning the equipment outright. The finance is a fixed-sum 0% credit agreement provided by HomeServe Finance Limited or Propensio Finance Limited, with Boxt acting as credit broker. There is also a headline-grabbing three-way option that adds a Tesla Model 3 to the bundle for a combined £494 a month.
What you are buying: the Powerwall 3 in brief
The Powerwall 3 is Tesla's third-generation home battery: 13.5 kWh of usable storage, an integrated solar inverter rated to handle up to 20 kW of solar input, backup capability, and the Tesla app ecosystem. It carries a 10-year warranty with unlimited cycles, one of the strongest warranty positions on the UK market (see our battery warranty comparison). On hardware quality there is little to criticise.
The questions worth asking are about fit and price, not quality. A 13.5 kWh battery with a high-power inverter is more capacity and more power than a typical UK three-bed home needs for tariff arbitrage, and the integrated solar inverter is wasted money if you never add panels. Note that a Powerwall's inverter rating also puts installations on the G99 application route rather than simple G98 notification, which can add weeks to the timeline depending on your DNO.
Bundle or battery-only? Run the solar maths first
The bundle adds roughly £3,950 to the cost of the battery-only finance route (£11,299 vs £7,345). Once a battery is charging cheaply overnight on a smart tariff, eight panels of solar only add around £250 to £350 a year of extra savings, which means the solar slice of the bundle takes 12 to 16 years to pay for itself. If you are not on a time-of-use tariff and plan to stay that way, the solar earns considerably more and the bundle case improves.
We work through this arithmetic in full, including who the bundle genuinely suits, in our Tesla £199 bundle deep dive. The one-paragraph version: strong fit for Tesla car owners with an unshaded south-facing roof who want one turnkey supplier and a fixed monthly cost; weak fit for anyone already on Octopus Go, Cosy or Intelligent Octopus Go who just wants the battery savings.
How the battery-only routes compare on price
| Option | Usable capacity | Total installed cost | Cost per kWh | Typical annual saving (Octopus Go) |
|---|---|---|---|---|
| Powerwall 3 via Boxt (cash) | 13.5 kWh | £7,499 | ~£555 | £800 – £950 |
| Powerwall 3 via Boxt (finance) | 13.5 kWh | ~£7,345 | ~£545 | £800 – £950 |
| Habo Energy 11.5 kWh | 11.5 kWh | £4,599 | ~£400 | ~£900 |
The annual savings are close because tariff arbitrage saturates: once the battery covers your full evening and overnight consumption, extra capacity stops adding savings. A typical home cycles 8 to 11 kWh through the battery daily, which both systems cover. The Powerwall's extra 2 kWh and higher power rating matter for large homes, heavy EV charging, or whole-home backup ambitions; they do not change the Octopus Go arithmetic for an average three-bed house. The £2,700 to £2,900 difference is the price of the Tesla badge, the bigger inverter, and the app ecosystem. For some buyers that is worth it. Our cost per kWh guide explains how to compare any two quotes on a level footing.
How to order through Boxt
The process is straightforward: get a quote on the Boxt website (Tesla's UK site routes Powerwall enquiries there), complete a remote survey with photos of your consumer unit and proposed battery location, pass credit approval if financing, then book the installation date. Boxt handles the DNO application and building-regulations notification. Check that your quote covers any G99 application fees and, for the bundle, scaffolding costs for the panel install.
Just want the savings, not the badge?
The Habo Energy 11.5 kWh battery is £4,599 fully installed, MCS-certified, pre-configured for Octopus Go, and G98-compliant by design so there is no DNO approval wait. Same annual savings as a Powerwall on the same tariff, £2,900 less spent.
Reserve for £49