System Inertia
Summary
NESO publishes estimates of outturn inertia and market-provided inertia for the GB transmission system, excluding Stability pathfinder contributions. This data tracks the system's ability to resist frequency changes as thermal generation declines and renewable capacity increases.
Why it matters
Inertia data reveals the growing frequency stability challenge as the grid transitions from synchronous thermal plant to inverter-based renewables. The exclusion of pathfinder units understates actual system capability, masking how much expensive stability services NESO procures to maintain grid frequency within statutory limits.
Key facts
- •Published July 2021
- •Excludes Stability pathfinder unit contributions
- •Covers GB transmission system only
Areas affected
Related programmes
Memo
This dataset contains an estimate of the outturn inertia and market provided inertia for Great Britain Transmission System. It does not include the contribution from Stability pathfinder units