GridHz

GB Grid Stability Digest

The week on the grid — 10–16 August 2026

Issue 2026-w33

Wind and solar peaked at 54.7% of GB generation at Tue 14:15.

System inertia ranged from 125.1 GVA·s to 204.8 GVA·s (average 163.6 GVA·s).

Vital signs

This weekvs last week
Inertia min / avg / max125.1 / 163.6 / 204.8 GVA·s▲ +21.3 GVA·s (min)
Frequency range (sampled)49.814–50.171 Hz · 158 samples beyond ±0.1 Hz▼ −0.013 Hz (min)
Peak wind + solar share54.7% (Tue 14:15)▼ −23.9 pp
Peak demand24.2 GW (Fri 01:15)▼ −1.8 GW
System price max / min£349/MWh / £48/MWh▲ +£151/MWh (max)

Event of the week

The system imbalance price peaked at £349/MWh in settlement period 44 on 2026-08-13.

Learn: Understanding RoCoF

Rate of Change of Frequency measures how fast grid frequency moves after a disturbance. Protection relays act on it, so operators keep it within tight limits.

Read the explainer →

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Data: Elexon BMRS · NESO · Carbon Intensity API · Sheffield Solar · All issues
Free to reuse with attribution (CC BY 4.0).