⚡ Off-Grid, Lithium-Free: UK’s First Sodium-Ion System Powers an Independent Site

31.07.2025

We’re proud to share a major milestone for both Eleven Energy and the UK energy storage industry: our first off-grid sodium-ion battery system has been successfully installed and commissioned by Icore Security Ltd.

This project, featuring a 6kW hybrid inverter and three 4.5kWh sodium-ion battery packs, is the first installation in the UK where a sodium-ion energy storage system is operating entirely off-grid – with no connection to the national electricity grid.

🔋 A New Era for Off-Grid Energy

Off-grid power solutions are becoming increasingly important in a world where energy resilience, independence, and decarbonisation are front of mind. Whether it's remote infrastructure, security systems, agricultural sites or critical communications, reliable power without grid access is often a challenge.

Traditionally, off-grid systems have depended on lithium-ion batteries, lead-acid banks or diesel generators – each with significant limitations around safety, cost, environmental impact, and sustainability.

This is where sodium-ion technology steps in.

🌱 Why Sodium-Ion is Ideal for Off-Grid Use

Our sodium-ion batteries are a safe, sustainable alternative to lithium-ion, using abundant raw materials and offering excellent performance in a wide range of environments – including the UK’s cold, damp winters.

For off-grid applications, sodium-ion brings some key advantages:

  • High thermal stability – Performs well in both high and low temperatures
  • No lithium or cobalt – Environmentally friendly and geopolitically stable

⚙️ The System in Detail

  • 6kW IP65 hybrid inverter – Suitable for indoor or outdoor installation
  • 3 x 4.5kWh sodium-ion battery packs – 13.5kWh total storage
  • Modular and scalable – The system can grow to meet future site needs
  • Fully off-grid – Designed for complete independence from the electricity grid

The system installed by Icore Security is now powering an off-grid site around the clock, showcasing sodium-ion’s reliability in a live, real-world scenario.

🔭 A Glimpse into the Future

This installation marks a significant step forward in the commercial deployment of sodium-ion energy storage. As the technology matures and production scales, we see huge potential for sodium-ion to play a leading role in off-grid, residential, and commercial energy systems – in the UK and beyond.

At Eleven Energy, we’re committed to pioneering this transition. We believe that clean, decentralised energy should be accessible to everyone – without relying on scarce or controversial materials.

Stay tuned for more updates as we continue to roll out our systems across the country.

Want to learn more about our sodium-ion systems or discuss an off-grid project?
Get in touch with our team →