Your Energy2 battery charges when it's cheap and powers your home when it's expensive. The savings are automatic, every... single... day.
17kWh of storage in a compact unit — more than a typical UK home5 uses in a whole day. Scale up to 272kWh with multiple modules.2
Rated for 6,000+ full cycles. 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 overnight 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 Black 17 | Tesla Powerwall 3 | |
|---|---|---|
| Useable Capacity | 16.9kWh2 | 13.5kWh6 |
| Made in Britain | Yes — designed, built & installed | No — manufactured in USA/China |
| Warranty | 15 years | 10 years |
| Cycle Life | 6,000+ 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 | 16.9kWh2 |
| Configuration | 16S1P |
| Nominal Voltage | 51.2V |
| Max Power Output | 10kW |
| Cycle Life | 6,000+ (see Warranty Terms) |
| Chemistry | LFP (Lithium Iron Phosphate) |
| Dimensions | 82 × 41 × 27cm |
| Weight | 110kg |
| Communication | CAN port |
| Scalability | Up to 16 units (272kWh) |
| Warranty | 15 years |
| Certification | Safety-Critical Components (Cells, BMS, Breaker): IEC 62619 Tested. System Design: Aligned to IEC 62619 (Limited Production Run) |
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.
Every home is different, so we provide a personalised quote after a free, no-obligation survey. This ensures you get an accurate price based on your actual energy usage and requirements, not a generic estimate. Our engineers will assess your property and recommend the right system for your needs. See our battery sizing guide for a self-service estimate. UK 0% VAT is applied automatically to residential installs.
Most domestic installations are completed within 48 hours. Our engineers handle everything from delivery to setup, testing, and activation. We'll agree a convenient time and keep disruption to an absolute minimum.
In most cases, no. Domestic battery storage systems are typically classed as permitted development. However, there are some exceptions for listed buildings and conservation areas. We'll advise you during your free survey if any permissions are needed.
Yes. We use Lithium Iron Phosphate (LFP) chemistry, which is the safest lithium battery technology available. LFP cells are thermally stable and do not experience thermal runaway. Our systems are fully certified to UK safety standards and carry MCS certification.
Our batteries are virtually silent in normal operation. Unlike some systems with active cooling fans, the Black 17 generates minimal noise that is unnoticeable in a typical home setting.
No. Our batteries work with or without solar. Many customers save significantly simply by charging from the grid during cheap off-peak hours (as low as 7p/kWh) and using that stored energy during expensive peak times (24p+/kWh). See our UK tariff guide for which Octopus tariffs work best with the V3 — including options for households without solar.
Our 15-year warranty is the longest in the UK domestic market. Because we design and manufacture our batteries in Britain, spare parts and servicing are always available. Unlike sealed imported units, our systems are designed to be serviced and maintained for decades.
Yes, our systems can be professionally relocated. We can arrange removal and reinstallation at your new property. A home battery also adds value to your property — energy efficiency improvements are increasingly attractive to buyers.
Book a free home survey and get a personalised quote. No obligation. No pressure. Just honest advice from the engineers who build them.
We don't publish prices online because every home is different. A free survey ensures you get an accurate, personalised quote — not a generic estimate.
Important information
Important Note: The energy performance and benefits of EESS is impossible to predict with certainty due to the numerous functions a system can be programmed to perform.
You should not sign a contract based on specific energy prices. Tariffs vary between suppliers and can change, so these costs can go up or down.