Helpful video reference. Eleven Energy, the Cambridge-based company behind the UK's first sodium-ion home storage system, published this installation walkthrough covering the Single Phase Hybrid Inverter, outdoor battery enclosures, battery module connection, and commissioning via the installer app. Watch on YouTube at https://www.youtube.com/watch?v=2LXYoC2NPds.
1. PAS 63100 site survey and DNO notification
Before any hardware arrives, a registered installer surveys the property. They check whether the consumer unit has a spare way for the inverter circuit, confirm the earthing arrangement, and assess the solar array's existing wiring if DC coupling is planned.
DNO notification is submitted under G98 (for most domestic systems up to 3.68 kW AC export per phase) or G99 (for larger systems or properties where the DNO has additional requirements). Eleven Energy's hybrid inverter is export-limited as part of commissioning, which keeps most domestic installations firmly within G98 territory.
2. Plan the inverter and battery locations
The Single Phase Hybrid Inverter is wall-mounted indoors, typically in a utility room, garage, or airing cupboard. It needs to be close to both the solar DC cable entry point and the consumer unit to keep cable runs short and voltage drop within limits.
The outdoor battery enclosures (Eleven Energy's IP65-rated "cool-box" style housings) go on a suitable external wall. The sodium-ion chemistry means there is no requirement for a fire-rated enclosure or a minimum separation from windows and doors, which simplifies siting compared to some lithium systems.
3. Install the outdoor battery enclosures
Each enclosure is fixed to the wall using the mounting bracket supplied. Battery modules slide into the enclosure and lock in place. The enclosures accept two 4.5 kWh modules each, giving 9 kWh per enclosure. Cable entry is via glands at the base.
The installer runs the inter-enclosure cables and the main DC cable back to the inverter at this stage, before the enclosure lids are closed. All outdoor connections are made to the torque settings in Eleven Energy's installation guide.
4. Mount the hybrid inverter
The inverter bracket is fixed to the wall and the unit hangs from it. Clearances above and below are specified in the installation manual and must be respected for cooling airflow. The inverter sits close to the consumer unit so the AC connection and CT clamp cable reach comfortably.
5. Connect the solar DC cables
The DC cables from the solar array run to the inverter's MPPT inputs. Polarity must be confirmed before connection using a DC voltage meter. Cables are routed in the cable safe zones defined in BS 7671 or protected in conduit where this is not possible.
Where an existing grid-tied inverter is already fitted, the installer assesses whether to retain it (AC coupling) or replace it with the Eleven Energy hybrid inverter (DC coupling). DC coupling is generally more efficient; AC coupling avoids disturbing existing wiring.
6. Wire the AC supply from the consumer unit
A new circuit runs from the consumer unit to the inverter's AC terminals. The RCBO rating and cable size follow the Eleven Energy installation specification, which depends on the inverter output. The circuit is Part P notifiable and is tested and certified as part of the completion documentation.
A double-pole isolator is fitted near the inverter so the unit can be de-energised without going back to the consumer unit. This is a maintenance requirement rather than a regulatory one, but most installers fit it as standard.
7. Fit the CT clamp
The current transformer (CT) clamp fits onto the meter tails or the appropriate cable at the consumer unit. It gives the inverter real-time data on how much power is being imported or exported, allowing it to optimise the charge and discharge cycle automatically.
CT clamp position matters: it goes on the live conductor between the meter and the consumer unit main switch. If the tails are too short to clip around, a short extension may be needed, done carefully and compliantly under the DNO's rules.
8. Commission via the Eleven Energy installer app
Commissioning is completed through the Eleven Energy installer app on a smartphone. The process includes Wi-Fi pairing, confirming the CT clamp is reading correctly, setting the import and export tariff (if using smart tariff integration), and configuring any export limitation required by the DNO notification.
The installer hands over the completed commissioning report to the homeowner and confirms the app is working correctly. The homeowner receives access to the Eleven Energy consumer portal showing live solar, battery, and grid data.
When to call us
Eleven Energy sodium-ion battery storage is specialist work that requires a registered installer, DNO notification, and the appropriate certification. Richard can advise on whether the system suits your property and arrange a quotation for the full installation including all paperwork.
Thinking about a sodium-ion home battery?
Richard can advise on whether Eleven Energy is suitable for your property and co-ordinate the installation, DNO notification, and completion certificates.
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