Long-duration energy storage need in GB could mostly be met by lithium-ion, investor says

February 19, 2025
LinkedIn
Twitter
Reddit
Facebook
Email

“We need to allow the technology to show us what the most cost effective solution for is 10-20-hour duration energy storage is”, managing director of Adaptogen Capital James Mills says.

Speaking on a panel at the Energy Storage Summit in London today, Mills said that in the long term, storage and batteries are the “only way” to solve the “massively complex” green grid due to be established by 2040.

While governments are currently primarily focused on the clean power targets set for 2030, continuing on to meet legally binding 2050 carbon reduction targets will require significant battery storage deployment, the panel agreed.

Paul Wakely, head of strategic network development at the UK’s National Energy System Operator (NESO), said batteries are important “in all time scales—it is now part of our daily life in the energy system”.

This article requires Premium SubscriptionBasic (FREE) Subscription

Try Premium for just $1

  • Full premium access for the first month at only $1
  • Converts to an annual rate after 30 days unless cancelled
  • Cancel anytime during the trial period

Premium Benefits

  • Expert industry analysis and interviews
  • Digital access to PV Tech Power journal
  • Exclusive event discounts

Or get the full Premium subscription right away

Or continue reading this article for free

Florent Xavier, director of R&D partnership, valorization and transformation for French transmission operator Réseau De Transport D’Electricité (RTE), said flexibility to enable security of supply is the “main one” in France, where over 5GW flexibility is needed to support the network by 2030.

Meanwhile, David Noronha, head of future networks & strategic offshore planning for Irish grid operator EirGrid, said in Ireland long-duration energy storage (LDES) is crucial to supporting the network of the future, but for all storage it “boils down to location”; the impact storage brings is “dependent on its location in the network”.

This was also the opinion of Andy Willis, CEO and co-founder of UK-based battery energy storage developer Kona Energy. The focus, according to him, should be on developing storage, in the short and long term, in areas that it can solve constraints. To enable batteries to thrive in this scenario, though, Willis said there needs to be proper renumeration: “There is a locational need for batteries, but their value is not being realised.”

Mills took this on, noting that there are two key issues for the grid of 2040: massive constraint complexity and the volume of terawatt-hour duration that the system will need.

“I feel for the transmission owners the green grid of 2040 will be massively complex in a mathematical sense. I don’t think it can be solved from the centre, [the system] can only optimise itself and remain stable if you allow co-optimisation in real time through price.

“My vision is that we will end up with a system of massively distributed BESS at almost every gap.”

Longer duration lithium

Although duration will necessarily increase, Mills said that, cost-wise, it is most likely that this will be realised using lithium-ion battery technology in the most part. There is “no doubt” that the difference between the energy system of today and the system of 2030-40 will be that “we need to push battery storage into 10h+ duration”.

For Mills, this is entirely feasible: “The rate of change in BESS technology and the cost curve is extraordinary.”

15 September 2026
San Diego, USA
You can expect to meet and network with all the key industry players again in 2025 from major US asset owners, operators, RTOs and ISOs, optimizers, software and analytics providers, technical consultancies, O&M technology providers and more.
13 October 2026
London, UK
Now in its second edition, the Summit provides a dedicated platform for UK & Ireland’s BESS community to share practical insights on performance, degradation, safety, market design and optimisation strategies. As storage deployment accelerates towards 2030 targets, attendees gain the tools needed to enhance returns and operate resilient, efficient assets.

Read Next

February 24, 2026
Panellists discussed M&A in large-scale BESS on the ‘M&A Market: How Attractive Is BESS Right Now?’ panel discussion at the Energy Storage Summit 2026.
February 24, 2026
How to enable bankability for large-scale BESS projects was the main topic of the opening panel discussion at the Energy Storage Summit 2026 which kicked off today (24 February).
February 24, 2026
Lightsource bp has sold a 1GW operational solar PV portfolio, with options to build 800MW of co-located battery storage, in Australia.
February 24, 2026
The recent successes of the energy storage market in Europe bring new challenges alongside industry maturity, writes Vicente Abad.
February 23, 2026
Fotowatio Renewable Ventures has unveiled plans for a 1.2GW/5GWh portfolio of battery energy storage system (BESS) projects in Spain.