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ESO
NOA Stability Pathfinder – Phase 2 updates
Phase 2 is focused on increasing Short Circuit Level in Scotland. Short Circuit Level is the amount of current that flows on the system during a fault.
As traditional coal and gas plants are phased out from Britain’s energy system, the transmission system short circuit levels are falling. Renewable generators like wind and solar connect to the grid in a different way, which doesn’t give us the same stabilising properties. So we need to find new providers to help support the system.
Latest updates
The feasibility study stage has now concluded and the connections review work is ongoing. An updated timeline for the Phase 2 process has been published here.
Step 1: Identify stability needs across Great Britain (complete)
The System Operability Framework (SOF) highlighted the operability risks expected due to the decline in transmission connected synchronous generation over the next decade.
Step 2: Launch RFI (complete)
We launched a Request for Information (RFI) for Phase 2 in June 2020, seeking feedback on the process we’d proposed and any impacts of Covid-19.
Step 3: Launch EOI (complete)
The Expression of Interest (EOI) was an opportunity for any interested commercial and network owners to submit their solutions. The EOI window for Phase 2 closed in January 2021 and submissions have been reviewed. A summary of submissions can be found here.
Step 4: Launch feasibility study (complete)
Solutions which passed the EOI stage were subject to a feasibility study to ensure they meet the technical specifications. This included the submission of desktop-based power system simulations and manufacturer datasheets or specifications. A feasibility study summary can be found here.
Step 5: Launch connections review (in progress)
Solutions without connection offers or agreements are undergoing the connections review process. The connections review scope document explains the scope of the work and associated limitations.
Step 6: Launch tender (pending)
Providers whose solutions pass the feasibility study will be invited to participate in the commercial assessment stage, where we assess commercial solutions alongside those submitted by network owners.
Providers whose tenders are accepted will be awarded contracts and can begin work on developing their solutions.