2026-041 Engineering and Cost Support for LDES

Ofgem is currently assessing Long Duration Electricity Storage (LDES) projects ('Project(s)') which have bid for the first LDES Cap & Floor Licences through application Window 1, and are working to design the next iteration of this process (Window 2).

Ofgem requires support from a supplier with the timely and appropriate assessment of technical project parameters submitted as part of LDES Window 1 and thereafter the technical aspects policy design for Window 2 and potentially the assessment of technical project parameters for Window 2. This work is key to delivering Ofgem's

statutory obligations, most notably protecting the interests of current and future consumers.

Ofgem needs support from a supplier to assess the VfM of proposed costs and project parameters which will affect the overall value of projects, and to design project reporting frameworks. Once projects have taken their Final Investment Decision (FID), Ofgem may also seek support to determine whether project spend represents best VfM

for consumers, especially if projects incur unanticipated costs as a result of Force Majeure (FM) type events, Changes in Law/Regulation, or issues that were not included in project risk registers. Thereafter, Ofgem will need support from the supplier to critically assess the outcome of Window 1 and refine and improve policies and processes used to bring projects forward through Window 2 and, depending on strategic decisions yet to be

made on the future of Window 2, to assess project submissions and Licence parameters for Window 2.