Commercial battery storage myths vs facts
| Myth | The fact | Verdict |
|---|---|---|
| Lithium batteries are a serious fire hazard on a commercial site. | Correctly specified modern systems use LFP cells, and commercial installations are designed to the IET Code of Practice for Electrical Energy Storage Systems, BS EN/IEC 62619 and BS EN/IEC 62933, with detection, thermal monitoring and separation (PAS 63100 is the dwellings standard). The risk lies mainly in poorly specified kit and poor siting. This is a genuine concern, handled by design, not a reason to avoid storage. | Concede + handle |
| A battery pays back in 3-4 years — the numbers are amazing. | Treat very short paybacks with caution. Payback depends heavily on the site: red-band DUoS exposure, solar surplus, and whether grid-services income is assumed, which has become more volatile. Ask for the payback to be modelled from your own half-hourly data, with any grid-services income shown separately as upside rather than the case. | Discredit inflated claim |
| Installing is quick — a few weeks and you are done. | The installation itself usually takes weeks, but the programme is set by the DNO: the G99 study and connection offer can take months. Submitting G99 at survey stage and using G100 limitation on constrained networks helps, but no honest installer can promise a fast go-live without the DNO position. | Myth |
| Commercial battery storage gets 0% VAT like home batteries. | No. The 0% VAT relief applies only to residential accommodation and relevant-charitable buildings, and reverts to 5% on 1 April 2027. General commercial premises do not qualify: the commercial route is capital allowances (the Annual Investment Allowance, then full expensing or the 50% first-year allowance depending on classification), not zero-rated VAT. | Myth |
| You need a big new grid connection to install a battery. | Often the opposite. A behind-the-meter battery with a G100 export/import limitation scheme can let you add load within your existing agreed capacity, if the DNO accepts it, avoiding or deferring a costly reinforcement. The battery is frequently the route around a constraint, not a victim of it. | Myth |
| Any electrical contractor can install a commercial battery. | Partly true, partly not. Many can wire the kit; far fewer can deliver the G99 application, G100 protection design, a fire strategy to the commercial references, half-hourly metering and witnessed commissioning. Ask to see a commissioning pack and a fire risk assessment from a comparable job. | Concede + clarify |
If you have heard a claim about commercial battery storage that sounds too good — a two-year payback, a same-month install, zero-rated VAT on a factory — check it against your half-hourly data and your DNO position before you commit. Read an independent view on whether it is worth it, and for the fire question, the standards that apply to a commercial battery.