“Black start is no longer about having a few new technologies—it’s about redefining what restart actually means,” says Dlzar Al Kez, Research Associate at Net Zero Infrastructure, in conversation with Strategic Energy Europe, when asked how the UK is preparing for events similar to the Iberian Peninsula blackout.

The traditional recovery model—based on thermal or hydro plants capable of starting without external supply—is no longer viable in a grid dominated by variable renewables. Technologies like solar and wind typically use grid-following inverters, which require a live grid signal to operate. “When the grid goes dark, they go dark too,” Al Kez highlights.

Grid-Forming Technology and Storage: The New Protagonists

In response, the UK is pursuing an innovative, distributed and adaptive approach, focused on three core pillars: enabling grid-forming capability, planning regional restart routes, and elevating the role of distribution network operators.

“Storage technologies, if configured correctly, can energise dead networks, establish voltage and frequency, and support stable reconnection,” says Al Kez. Grid-forming batteries are increasingly expected to replace the role of traditional synchronous machines in blackout scenarios.

From Centralised Recovery to Regional Restart Pathways

This technical progress must be accompanied by a shift in operational planning. The country can no longer assume the system will restart from a single, central location. Instead, it is developing regional restart strategies, especially in areas with high renewable penetration or far from legacy black start hubs, such as northern Scotland and offshore corridors.

“We can’t keep thinking everything will restart from a central hub. Places like the North, the South West or offshore corridors need local restart strategies—based on grid-forming inverters, synchronous condensers and zonal planning,” Al Kez explains.

The Rising Role of Distribution Network Operators

This transition also demands a greater role for Distribution Network Operators (DNOs). In line with this, the National Energy System Operator (NESO) is promoting the Distributed Restart programme, which explores how small-scale assets on the distribution grid can actively support system restoration, instead of waiting passively for reconnection from the transmission network.

Interconnectors: Strategic Allies, Not Guarantees

Another key focus is the role of interconnectors. Although they do not share frequency or inertia with the British system, as HVDC links, their value is increasing as tools for balancing and cross-border flexibility. “If one of these links trips during low-inertia conditions, it can trigger rapid frequency swings,” warns Al Kez. The UK’s 2019 blackout exposed just how vulnerable the system can be during compounded events.

For this reason, the UK is not only expanding its interconnector capacity but also ensuring new links include built-in ramp rate control, fault ride-through and interface protection from day one. “Interconnection makes the system more efficient, but it doesn’t make it immune,” Al Kez affirms.

Structural Lessons from the Iberian Blackout

Structurally, the British grid has notable advantages over Iberia’s. It features a highly meshed transmission network, a single national system operator with full oversight, and tools such as Dynamic Containment to enhance operational resilience. However, “resilience today isn’t just about structure—it’s about how fast the system can respond, how well distributed assets are coordinated, and whether control systems are designed for the grid we actually have, not the one we used to have,” stresses Al Kez.

Engineered Stability: A New Pillar of the Energy Transition

The energy transition demands more than just clean generation—it requires a new way to protect, restore and stabilise the grid under pressure. The UK is moving beyond reactive crisis management, investing instead in smart planning and rapid-response technologies.

“Stability is no longer a passive attribute of the system. It has to be actively engineered—with real-time controls, distributed coordination, and fast-response tools embedded at every level,” concludes Dlzar Al Kez, of Net Zero Infrastructure.