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What happens when supply runs tight?

When the Grid is Tested

A renewable grid's hardest hours — the windless, sunless spells it must plan for, the batteries that ride the gap, and the day the lights actually went out.

Dunkelflaute Chart

The cold, dark, windless spells when wind and solar all but vanish and the price climbs.

14 spellsspells on record since 2021

Storage Chart

The batteries that live off the daily spread — charging cheap midday, discharging into the peak.

~6×grid storage since 2021

Capacity & Adequacy Chart

Can firm capacity cover the worst residual-load hours — and what the policy to ensure it costs.

12 GWgas tender, provisional

Iberian Blackout Historical

A sober, sourced replay of 28 April 2025 — what the grid data recorded, asserting no cause.

Shows what the grid data recorded. Asserts no cause.

~0.1 GWPT load at the floor
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