UK battery storage faces major cyberattack risk, study

Centrii has published an analysis warning there is a 92% probability of a major cyberattack on UK battery energy storage infrastructure within five years. The study puts the potential cost of a single major incident at up to GBP £10 billion.

The report examines a scenario called GRIDLOCK, in which attackers compromise multiple battery energy storage system units to disrupt the balance of the electricity grid. Under industry-average security practices, it concludes that an attack on the UK sector is highly likely before the next decade begins.

According to the modelling, compromising 29% of national battery storage capacity, or about 400 units, could be enough to trigger a nationwide outage affecting 67 million people. The analysis estimates the financial damage from such an event at between GBP £2 billion and GBP £10 billion.

Centrii based its findings on 10,000 Monte Carlo simulations across three security postures: baseline, moderate and aggressive. In the model, the probability of a major attack falls to 78% if security improvements are adopted gradually across the sector, and to 61% if operators implement mandatory IEC 62443 certification and regular attack-readiness drills.

The report also argues that stronger security measures would delay the likely timing of a serious incident. Under its baseline scenario, the earliest attack window is 2027 to 2028; under the most rigorous posture, it shifts to 2029 to 2031.

Grid risk

Battery storage has become an increasingly important part of the electricity system, helping grids balance supply and demand, store surplus wind and solar generation, and provide backup during periods of peak use. As more of these assets are managed remotely through cloud-based systems, researchers and operators have raised concerns that the sector is creating new points of vulnerability.

The analysis says the attack would not need to damage battery hardware or shut down generation directly. Instead, it would interfere with how battery fleets respond to grid signals, causing multiple units to charge or discharge at the same time or respond too slowly to changes on the network.

Rafael Narezzi, Co-Founder and Chief Executive Officer of Centrii, described the mechanism in detail.

“A coordinated attack does not need to stop generation to cause a blackout. It only needs to desynchronise the balancing layer, forcing batteries to charge or discharge together, or delaying how they respond to grid signals. Neither action damages a battery. The effect is closer to a distributed denial-of-service attack than a conventional outage - instead of overwhelming a website with traffic, it overwhelms the grid's ability to stay in balance, using energy itself as the disruptive force. The modelled result is a cascading blackout that unfolds in under two minutes,” said Rafael Narezzi, Co-Founder and Chief Executive Officer of Centrii.

Centrii estimates that raising UK battery storage infrastructure to IEC 62443 Security Level 2 would cost between GBP £400 million and GBP £1 billion across the national fleet. Compared with the estimated losses from a major attack, the report suggests preventive spending could deliver a return of roughly five to 25 times.

US comparison

The study also modelled a coordinated attack on the battery fleet supporting the Texas grid in the United States. In that scenario, it estimated economic damage of USD $12 billion to USD $65 billion, while the cost of bringing the ERCOT battery fleet to IEC 62443 Security Level 2 was put at USD $800 million to USD $2.8 billion.

In Texas, the threshold for serious disruption was lower as a share of total capacity but involved more sites in absolute terms. The report said compromising 5.4% of the ERCOT battery fleet, or around 1,500 units, could be enough to destabilise the grid and potentially affect 30 million people.

In the UK, the concentration of impact is sharper because a smaller share of national battery capacity is modelled as sufficient to produce nationwide effects. The finding comes as the country prepares for a significant rise in battery deployment over the rest of the decade.

Government estimates cited in the report suggest the UK will require between 23GW and 27GW of battery storage by 2030, up from about 4.5GW in 2024. That scale of expansion means cyber risk in grid-balancing infrastructure is likely to attract greater scrutiny from operators, investors and policymakers.

Recent grid events in Europe have added to concerns about how quickly disruption can spread through interconnected systems. The report points to an attempted effort by state-backed actors in Poland to destabilise regional grid infrastructure by rapidly cycling wind turbine output, and to the collapse of the Iberian grid after 2.5GW of generation was lost in less than 20 seconds. Authorities attributed the Iberian outage to technical causes rather than a cyberattack.

Narezzi said boards have lacked a clear financial benchmark for cyber risk in operational technology.

“Every board I speak to already accepts that cyber risk exists. What they haven't had is a definitive assessment that helps them to reach the right figure. Security spending in operational technology is rarely treated as return-generating, because its value shows up in an event that does not happen. This modelling makes that value visible and measurable. Based on these figures, protecting battery storage is one of the highest-return decisions available anywhere in the business, but it's also one of the least discussed at board level,” said Narezzi.