Battery Energy Storage System (BESS) Insurance

Why Battery Storage Insurance Has Become So Hard to Buy

Battery energy storage is one of the fastest-growing sectors in the UK — and one of the hardest to insure. Insurer appetite has tightened sharply in response to high-profile lithium-ion fires, and much of the remaining capacity is being reserved for large utility-scale portfolios. The result is a squeeze on smaller and mid-sized operators: punitive premiums, restrictive conditions, blanket exclusions, or outright declinature at renewal.

If you operate a commercial battery storage site, install systems for clients, or have added behind-the-meter storage to your farm, factory or commercial property, you may already have discovered that your existing broker cannot place the risk — or that your commercial combined insurer has added a battery exclusion without much explanation. If that has already happened, our guide to battery storage cover that has been declined or non-renewed sets out the route back in.

Who We Arrange Battery Storage Insurance For

What a BESS Insurance Programme Should Include

Property Damage & Fire

The core of any battery storage policy. Cover for the battery units, inverters, transformers, balance of plant and containers against fire, thermal runaway events, storm, flood and theft. Wording matters here: some policies restrict or exclude damage originating from cell failure, which is precisely the loss you most need covered.

Business Interruption & Loss of Revenue

Battery storage sites earn through trading, grid services and demand management. A fire or equipment failure can take a site offline for many months given current supply chains. Business interruption cover should reflect realistic reinstatement timescales and your actual revenue streams — not a generic indemnity period. We explain why ordinary income cover does not fit a battery asset in our guide to business interruption insurance for battery storage revenue.

Public & Products Liability

Third-party injury and property damage arising from your site or your installed systems, including fire spread to neighbouring property — a key concern for behind-the-meter installations in shared or adjacent premises.

Design & Professional Indemnity

For installers and EPC contractors: claims alleging design errors, incorrect specification, or system underperformance. Increasingly demanded by principals and funders before contract award — we cover this in full in our guide to battery storage installer and EPC contractor insurance.

Contract Works / Construction All Risks

Cover for systems during installation and commissioning — when batteries are at their most vulnerable and often not yet under the operational policy.

Environmental & Additional Covers

Environmental liability for pollution arising from a battery incident, machinery breakdown, terrorism, and decommissioning or grid deposit bond requirements where applicable.

What Insurers Want to See Before They Quote

BESS underwriting is risk-information driven. The difference between a declinature and a competitive quote is usually the quality of the submission. Insurers will look closely at:

• Battery chemistry and manufacturer — tier-one cells with established loss records are viewed very differently from unbranded systems.
• Thermal runaway mitigation — battery management systems, gas detection, ventilation and suppression appropriate to the chemistry.
• Separation distances — between containers, and from buildings, boundaries and neighbouring property.
• Monitoring — 24/7 remote monitoring of cell-level data, with documented response procedures for abnormal readings.
• Standards and certification — installation to recognised standards, commissioning records, and planned maintenance regimes.
• Fire service liaison — site information packs and access arrangements for emergency response.

We prepare submissions that present these factors properly, which is how risks that have been declined elsewhere get placed at sensible terms. Our detailed guide to lithium-ion fire risk and what battery storage insurers require walks through each of these factors and why they matter.

Why Use Miller & Partner for Battery Storage Insurance?

We are an independent, FCA-authorised commercial insurance broker specialising in energy infrastructure and hard-to-place commercial risks. We already act for heat network operators and renewable energy businesses, so we speak the language of energy assets, revenue stacking and grid obligations — and we know which insurers currently have genuine appetite for battery storage rather than a polite no.

Because we are independent, our advice represents you. We review your full risk presentation, approach the right markets directly, and structure cover around how your business actually earns — not around what a call centre script allows.

Battery Storage Insurance — Frequently Asked Questions