2025 Iberia Blackout Report [pdf]

Role of Renewables vs. Market Design

• Many commenters stress the blackout was not “renewables = bad” but a multifactor event: price-driven dispatch, grid design, voltage control rules, and plant non-compliance all interacting.
• Others argue high penetration of intermittent renewables inherently stresses a grid built for large synchronous plants, and that their system-level costs/externalities are underpriced.
• Debate over subsidies: one side says guaranteed prices and contracts-for-difference kept solar online at deeply negative prices, distorting behavior; others counter that modern wind/solar are cheapest even without subsidies and that total-system cost is what matters.

Voltage Instability, Not Just Inertia

• Several participants highlight the report’s statement that inertia (spinning mass) was not the root cause; the trigger was a voltage problem and cascading disconnection of generation.
• Chain described as: oscillations → remedial actions that increased reactive power issues → overvoltages → automatic trips → further overvoltage and disconnections → collapse.
• Key point: conventional synchronous plants were supposed to provide dynamic voltage/reactive support and in some cases failed or behaved atypically; many renewables were locked into fixed power-factor behavior by regulation and could not help.

Oscillations, Markets, and Control

• Some see evidence of a harmful feedback loop between quarter‑hour market pricing, fast-responding solar/wind, and grid conditions (“algorithmic trading with physical consequences”); others caution that this is suggestive but not fully proven.
• Multiple commenters note insufficient monitoring/estimation: large oscillations were observed but not well understood in real time, so operators resorted to heuristic actions (reconfiguring ties, flows) that had side-effects on voltage.

Storage and Grid Architecture

• South Australia’s blackout and subsequent large Li-ion batteries are cited as a successful template for fast frequency and inertia-like support; skeptics question inverter peak current limits, supporters respond with real projects providing multi‑GW “equivalent inertia” for short durations.
• Pumped hydro is discussed as complementary but geographically constrained; many prime sites are said to be already used, with economics marginal for new ones.

Cybersecurity and Politics

• Readers note the report devotes many pages to cyber/IT measures despite finding no cyberattack, interpreting this as seizing a rare opportunity to push long-needed security upgrades and to counter early hacking rumors.
• Some believe the public report is politically sanitized (e.g., redactions around why specific plants failed to start), while others emphasize that the technical story already shows multiple conventional and renewable actors not delivering contracted services.