The Iberian blackout has highlighted the critical importance of electricity security

It is still too early to conclusively isolate the causes of the recent Iberian blackout in April, which affected tens of millions of people across Spain and Portugal, or to assign responsibility. Official assessments will be essential to fully understand what occurred.

These will come from national authorities as well as from the expert panel convened by the European Network of Transmission System Operators for Electricity (ENTSO-E), with participation from regulators, including the EU Agency for the Cooperation of Energy Regulators(ACER). The investigations, required under EU legislation, will provide the data-based insights needed to comprehensively understand the incident and inform next steps to minimise the risk of such an incident occurring again.

While a considerable amount of public attention has focused on the share of renewable power sources in Spain's electricity generation at the time of the outage, there is not enough information available yet to determine whether this may have been a factor or to what extent.

In the meantime, the heightened international attention the blackout has brought to electricity security issues provides an opportunity to revisit some common elements of security and resilience as power systems evolve and decarbonise. While electricity systems and market structures vary widely around the world, IEA analysis has identified four critical pillars that apply across diverse geographies and circumstances:

• Robust infrastructure and supply chains: Building a solid foundation for power systems requires robust grid networks, including regional interconnections; diverse energy supplies; secure supply chains for critical components; and strategic reserves to buffer against disruptions.
• Diverse flexibility resources: Essential for system balance, power system flexibility can be achieved by adopting demand-side response mechanisms, developing and retaining dispatchable generation capacity, storage facilities and designing markets that appropriately value and incentivise these services.
• Technical stability solutions: Power quality and system integrity, which includes inertia, can be supported by utilising dedicated devices - including batteries with fast frequency response services, synchronous condensers or innovative converters with grid-forming capabilities - alongside conventional generators.
• Adapting operations: As power systems transform, stakeholders should adjust their operational frameworks to accommodate changes, including by updating and enhancing grid codes, reserve requirements, balancing mechanisms and new regulatory structures.

Effectively tackling these priorities calls for coordinated action by system operators, policy makers, regulators and the private sector. It also requires greater investment in electricity systems broadly as they modernise and grow.

One of the biggest energy security risks today relates to electricity grids. After remaining almost flat for a decade, annual spending on grids climbed by about 10% in 2023 and again in 2024, reaching just nearly USD 400 billion last year - suggesting that some countries are starting to respond to the challenges facing their electricity systems. Even so, to fulfil national energy plans and meet countries' energy-related goals, annual grid investment worldwide needs to reach USD 700 billion by 2030.

Increasing the flexibility of electricity systems is also urgent. According to IEA analysis, short-term flexibility needs in key electricity markets around the world are projected to more than double by 2030 due to growing demand for cooling, the uptake of electric vehicles, and rising shares of solar and wind generation. To meet these needs, all available sources of flexibility - including dispatchable generation, storage and demand response - will be necessary, as well as grid infrastructure to make the best use of them.

On technical stability, it is important to note that while proven solutions exist, implementation faces significant barriers. New technologies - including dynamic line rating, grid-forming inverters, synchronous condensers and advanced forecasting tools - can help manage grids and ensure quality access to stable power, but they are often underutilised. These solutions also require increased investment, which can be catalysed through modernised regulatory frameworks with improved incentive structures.