Octopus Energy Group and Gresham House sign biggest battery-leasing deal in the world

  • Battery behemoth Gresham House leases 900 MWh of its portfolio management to Octopus Energy Group’s Kraken
  • New deal unlocks Kraken’s cutting-edge asset optimisation to help slash the £800m annual wastage of ‘curtailment’ costs
  • A more effective and efficient grid will drive down energy costs for all

London, 5th June 2024 - Octopus Energy Group, the largest electricity provider in the UK, has signed a record-breaking battery leasing deal with Gresham House Energy Storage Fund plc (GRID) that uses its Kraken platform to unlock the benefits of the green grid for all.

The deal – the biggest of its kind in the world – will connect just over 50% of GRID’s large-scale batteries to Octopus’ technology platform Kraken. Kraken’s unique AI and machine learning optimisation will charge GRID’s batteries when renewable energy is abundant and discharge them when the national grid is under stress.

This intelligent flexibility reduces wasteful instances of ‘throwing away’ cheap clean power - such as when wind turbines are forced to stop turning because of too much energy on the national grid.

The issue is known as ‘curtailment’ in the energy industry and hit UK energy bill payers with a staggering £800 million of costs in 2022*.

Launched in 2018, GRID is already the largest battery energy storage fund in the UK, owning c.20% of the UK battery storage market. Octopus will take over half of GRID’s large-scale battery fleet in the UK for the next two years.

The 14 large-scale batteries can store more than 900MWh of renewable energy – enough to power 1 million homes for an hour, or a city the size of Birmingham.

This deal follows hot on the heels of Octopus reaching 1GW worth of shiftable load – the largest virtual power plant in the UK – through its electric vehicle (EV) tariff, Intelligent Octopus Go.

Kieron Stopforth, Head of Flexibility at Octopus Energy, said: "Every year the UK loses hundreds of gigawatt-hours of clean energy because our system isn’t flexible enough to keep it – PLUS have to pay for this senseless waste.

“Batteries unlock the clean and cheap energy system, storing green energy when it’s plentiful and providing it back to the grid when energy is expensive - and work even better with brilliant tech to manage that optimisation,

“Through this landmark deal with Gresham House Energy Storage Fund, we’re not only increasing the size of our virtual power plant to over 1.5GW, we’re also unlocking the power of flexibility, aiming to drive down grid costs.”

Ben Guest, Fund Manager of Gresham House Energy Storage Fund plc & Managing Director of Gresham House New Energy, said: "These new contracts with Octopus Energy secure revenues which are above those currently being achieved in the national market, demonstrating the value batteries can provide in balancing supply and demand for retail and wholesale market players."


Notes to editors

* Carbon Tracker, Gone with the wind? - Lorenzo Sani, 15th June 2023

Press Contacts

Octopus Energy Group

Press team


+44 (0)20 4530 8369

Gresham House

KL Communications:

Charles Gorman

Charlotte Francis

Effie Aye-Maung-Hider


+44 (0)20 3882 6644

About Octopus Energy

Octopus Energy is a global clean energy tech business, driving the affordable, green energy system of the future. Under its own retail brand, Octopus delivers world-class customer service and cutting edge energy products to 7.8 million households globally.

Its operations span 18 countries and the entire energy value chain. The group invests in, builds and flexibly manages renewable energy, operating a £7 billion portfolio of projects – one of Europe’s largest.

Octopus has licensed its advanced data and machine learning platform, Kraken, to support over 54 million customer accounts worldwide through licensing deals with companies such as EDF, E.ON and Origin Energy.

Kraken enables Octopus to drive the electrification of heat and transport through smart tariffs and innovative cleantech. Backed by pension funds, investors and energy giants, Octopus Energy Group businesses deliver cheaper, greener energy and cutting-edge tech to countries and customers worldwide.

For more information, check out our website.

About Gresham House and the Gresham House Energy Storage Fund:

Gresham House Energy Storage Fund plc seeks to provide investors with an attractive and sustainable dividend over the long term by investing in a diversified portfolio of utility-scale battery energy storage systems (known as BESS) located in Great Britain and internationally. In addition, the Company seeks to provide investors with the prospect of capital growth through the re-investment of net cash generated in excess of the target dividend in accordance with the Company's investment policy.

Gresham House Asset Management is the FCA authorised operating business of Gresham House Ltd, a specialist alternative asset manager. Gresham House is committed to operating responsibly and sustainably, taking the long view in delivering sustainable investment solutions.


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