The Energy2 V3 Black — 17kWh of British-made battery storage. The highest capacity domestic battery in the UK. 15-year warranty. Installed in a single day.
Electricity costs as little as 7p/kWh overnight but up to 27p/kWh at peak. Your Energy2 battery charges when it's cheap and powers your home when it's expensive. The savings are automatic, every... single... day — for the next 20 years.
Your battery charges automatically during the cheapest off-peak hours — typically 12am to 5am at around 7p/kWh.
During the day, your home runs on stored energy instead of expensive peak-rate electricity at 27p/kWh.
Up to 75% off your electricity bill. £1,500–2,500 in annual savings after a 5–7 year payback period.
17kWh vs 13.5kWh. The highest energy density domestic battery available in Britain. And unlike Tesla, it's designed, manufactured and installed by British engineers — with a 15-year warranty, not 10.
17kWh of useable storage in a compact unit. Enough to power most homes for an entire day. Scale up to 272kWh with multiple modules.
12,000 cycles at 80% depth of discharge. LFP chemistry — the safest, most durable battery technology available. Fire-resistant by design.
Complete off-grid capability. When the power goes out, your lights stay on. Genuine energy independence for your home.
Works perfectly with existing or new solar panels. Store excess generation and use it when the sun goes down. Compatible with all major inverters.
Designed to work with heat pumps. Charge the battery at 7p/kWh and run your heat pump at a fraction of the cost — 4× more efficient than gas.
Engineered as repairable infrastructure, not a sealed appliance. If a component needs attention, we replace the part — not the entire battery.
| Energy2 V3 Black | Tesla Powerwall 3 | |
|---|---|---|
| Useable Capacity | 17kWh | 13.5kWh |
| Made in Britain | Yes — designed, built & installed | No — manufactured in USA/China |
| Warranty | 15 years | 10 years |
| Cycle Life | 12,000 cycles | ~6,000 cycles (25 years) |
| Off-Grid Capability | Full off-grid | Limited backup |
| Data Hosting | UK data centres | Tesla cloud (USA) |
| Serviceability | Component-level repair | Full unit replacement |
| Installation | 1 day, by our engineers | Varies by third-party installer |
| Inverter Compatibility | Victron, Sunsynk, Growatt, Solis | Tesla inverter only |
| Useable Capacity | 17kWh |
| Configuration | 16S1P |
| Nominal Voltage | 51.2V |
| Max Power Output | 10kW |
| Cycle Life | 12,000 @ 80% DoD |
| Chemistry | LFP (Lithium Iron Phosphate) |
| Dimensions | 82 × 41 × 27cm |
| Weight | 110kg |
| Communication | CAN port |
| Scalability | Up to 16 units (272kWh) |
| Warranty | 15 years |
| Certification | IEC 62619 and UKCA |
We survey your current and future energy usage and design a system around your property.
A detailed proposal with system design, projected savings and estimated payback period.
Our engineers install your system in a single day. No subcontractors. The same people who build it, install it.
Design your system in minutes, or book a free home survey. No obligation. No pressure. Just honest advice from the engineers who build them.