European grid operators seek voltage control
- European grid operators and Portuguese lawmakers moved on April 28, 2026 to tighten voltage-control rules and backup-power standards after last year’s Iberian blackout. - ENTSO-E said the April 28, 2025 outage followed rising voltage, generator trips and cascading failures; Portugal wants 72-hour autonomy for hospitals and emergency services. - The push follows reports that the blackout unfolded in under 90 seconds and exposed outdated grid rules. (entsoe.eu)
Europe’s grid operators are pushing tighter voltage-control rules after the April 28, 2025 blackout that cut power across Spain and Portugal. (entsoe.eu) ENTSO-E, the European Network of Transmission System Operators for Electricity, said in its final report on March 20, 2026 that the outage came from interacting failures, not a single fault. The chain included oscillations, gaps in voltage and reactive-power control, generator disconnections in Spain and uneven stabilisation capabilities. (entsoe.eu) The blackout began at 12:33 CEST on April 28, 2025 and became the most severe outage on the European power system in more than 20 years, ENTSO-E said. A small area of southwest France near the Spanish border also saw brief disruption. (entsoe.eu) Voltage is the electrical pressure that keeps power moving through the grid, while reactive power is one of the tools operators use to keep that pressure from rising too high or falling too low. ENTSO-E said the Iberian system lost control of those dynamics fast enough to trigger cascading disconnections. (entsoe.eu) Euronews reported on April 28, 2026 that a Portuguese parliamentary working group has now proposed mandatory backup-power targets after concluding the government’s first response relied on “intuition” rather than an established plan. The group said hospitals, health centres, nursing homes and emergency services should be able to run for at least 72 hours without grid power. (euronews.com) The same Portuguese report calls for at least 24 hours of autonomy for other critical infrastructure, a higher fuel-storage cap of 3,000 litres instead of 500, and an alert system that does not depend on commercial mobile networks. It also recommends changes to SIRESP, Portugal’s emergency and security communications network. (euronews.com) Spain had already started rewriting voltage rules after the outage. Reuters reported on June 19, 2025 that Spain’s regulator updated 25-year-old grid rules so renewable plants such as solar and wind could provide voltage-control services that had largely been reserved for conventional and hydro plants. (uk.news.yahoo.com) That change widened the pool of plants the grid operator can call on when setting the next day’s power mix. Spain’s government had said days earlier that the system lacked sufficient voltage-control capability on the day of the blackout. (uk.news.yahoo.com) (marketscreener.com) One year on, the policy response is moving on two tracks: more generators being required to help steady voltage, and more essential services being required to survive when the grid fails anyway. (entsoe.eu) (euronews.com)
