Battery energy storage system (BESS) developer Root-Power has today (10 June) announced that it has submitted plans for four energy storage projects into Ofgem’s long-duration energy storage (LDES) tender.
The four LDES projects submitted by Root-Power for the cap and floor scheme will have a combined 2.4GWh of storage capacity and will, if approved, be built in West Yorkshire, North Yorkshire, Buckinghamshire and Lincolnshire. All four projects will make use of vanadium flow battery systems, a technology which, at present, is relatively uncommon in the UK BESS sector.
Prior to today’s announcement, Root-Power has almost exclusively been involved in delivering 2-hour and 4-hour lithium-ion battery projects, as opposed to the 8-hour duration vanadium flow batteries set to be used for the proposed projects.
Ofgem’s cap and floor investment support scheme for LDES projects launched in April of this year, following an extensive collaborative development process between the Department for Energy Security and Net Zero (DESNZ), the National Energy System Operator (NESO) and Ofgem.
The scheme aims to encourage the development of more LDES projects by balancing investor confidence and public value for money by setting minimum and maximum revenues that can be gained from LDES projects. The first application window for the scheme closed yesterday (9 June 2025). To date, most of the projects expressing interest in the scheme have been pumped hydro energy storage (PHES) projects rather than battery energy storage proposals.
Root-Power was launched in July of last year as a specialised BESS offshoot of the YLEM Group, and has since progressed over 40 projects through some stage of development. At the end of last month, the developer announced that it had broken ground on the Dounreay BESS, a 34MW/68MWh BESS development located in a remote coastal area in the Scottish Highlands; the location was specifically chosen to support the “major overhaul” expected from wind power development in the years to come.
Neil Brooks, managing director at Root-Power, said that the company is committed to leading the future of energy storage in the UK. He added: “Our team has been carefully developing these projects for some time, and it is fantastic to see the culmination of that work as these projects join our wider portfolio of battery energy storage systems.”
