Allianz UK has expanded its underwriting capability for battery energy storage systems (BESS), giving brokers access to specialist support as clients increasingly explore renewable energy projects involving grid-scale battery installations.
The move comes as battery storage becomes an increasingly critical part of the UK's low-carbon energy infrastructure, helping to manage intermittent renewable generation and strengthen grid resilience.
As of June 2026, Great Britain has around 10 gigawatts of grid battery capacity, with government targets pushing that figure towards 24 to 27 gigawatts by 2030.
According to the Department for Energy Security and Net Zero and Ofgem, battery capacity in the grid connections queue already exceeds the government's 2030 target range by around 14.8 gigawatts, with total surplus capacity in the queue reaching 61.7 gigawatts against 2035 system requirements, reflecting the scale of investment now flowing into the sector.
For brokers, that growth is translating into more clients bringing forward BESS risks, often in a market where insurer appetite and expertise are not evenly distributed.
Developed in the UK and drawing on Allianz's global energy underwriting expertise, the new proposition has been designed for mid-market energy clients and can be tailored to address complex risk features on a project-by-project basis.
Onshore generating stations, including battery storage, are classed as Nationally Significant Infrastructure Projects (NSIPs) once capacity exceeds 50 megawatts, requiring a Development Consent Order rather than standard local planning permission.
Reforms under the Planning and Infrastructure Act 2025, taking effect from 24 July 2026, are intended to speed up the NSIP consenting process, including faster examinations and earlier Planning Inspectorate input.
For brokers and underwriters, that matters because it points to more large-scale, higher-value BESS projects reaching construction and operational stages more quickly, increasing both the sums insured at stake and the technical complexity underwriters must assess.
Battery storage has grown quickly, but insurers have approached it cautiously.
Thermal runaway, the chain reaction in which a damaged lithium-ion cell releases heat that can cascade through adjacent cells and trigger a fire, remains the dominant concern for underwriters.
A number of insurers have restricted or withdrawn capacity from the sector following battery fires in the UK and overseas. Coverage now typically depends on evidence of adequate fire mitigation, including deluge or gas suppression systems, battery management system monitoring and emergency response planning aligned with National Fire Chiefs Council guidance for fire and rescue services.
Christian Simpson (pictured), head of Construction, Engineering and Energy Insurance, Technical and Underwriting at Allianz UK, said the enhanced proposition underscored the insurer's commitment to supporting the transition to net-zero by providing comprehensive cover for low-carbon technologies and renewable energy projects.
Simpson said battery storage is becoming an increasingly important part of the UK's renewable energy infrastructure, with more clients exploring opportunities in the space, and that early engagement with experienced underwriters and renewable energy specialists is valuable given how quickly the risk landscape is developing.
He added that by working closely with Allianz Commercial, the insurer aims to give brokers clearer access to the right expertise across the group, so they can bring BESS opportunities forward with confidence and discuss the controls in place on each project.
The expanded BESS offering sits alongside Allianz UK's established renewable energy capability across wind, solar, hydro, biomass, anaerobic digestion and short-term operating reserve, giving brokers a single route into the insurer's specialist teams across the renewables sector.
Allianz said the expansion forms part of a wider renewable energy strategy, aimed at supporting brokers and clients as they respond to a fast-changing energy market.
The expansion arrives at a point when the UK BESS sector is maturing rapidly but unevenly from an insurance perspective.
Larger, more sophisticated projects with strong fire mitigation and clear technical documentation are increasingly able to secure competitive terms, while smaller or poorly evidenced risks continue to struggle for capacity as insurers remain selective.
With gigawatt-scale projects now entering the pipeline, faster NSIP consenting bringing more large projects to market, and the government's Clean Power 2030 ambitions driving continued build-out, brokers working in this space are likely to place a growing premium on insurer partners able to combine technical underwriting depth with early-stage risk engagement, rather than treating BESS as a standard renewables add-on.
