Battery storage for business — FAQs

Published UK bands put installed commercial battery storage at roughly £20,000 to £40,000 for up to 100 kWh, £80,000 to £250,000 or more for 200 to 500 kWh, and around £140 to £240 per kWh for containerised systems of 500 kWh and above (Reonic, July 2026, drawing on Heatable and GSL Energy). The bands overlap, they are working ranges for a first conversation, and the source does not say whether they include VAT. The cost page sets out the sources, the arithmetic and a calculator.

This site publishes no typical figure, because none is sourced. Simple payback is the installed cost divided by the annual benefit, and the benefit depends on your half-hourly demand, your tariff and charges, and which value streams the battery can stack: peak-shaving and red-band DUoS avoidance, load shifting, solar self-consumption and, for some sites, grid-flexibility revenue. The peak shaving calculator applies the published network rates to your own peaks, and the cost page has a calculator that does the arithmetic on figures you supply.

Usually in several ways at once. It can shave your peak demand to cut time-banded distribution charges and the capacity you pay for. It can charge when electricity is cheap and discharge when it is dear. If you have solar, it can store surplus generation so you use it instead of exporting it. And on some sites it can earn from grid-flexibility schemes through a supplier or aggregator. Which of these apply, and how much each is worth, depends on your own load.

Sometimes. Two routes are documented on our funding page: NESO's Demand Flexibility Service, where the minimum size fell from 1 MW to 0.1 MW in April 2026, and the Capacity Market, which has a 1 MW minimum per unit that aggregators help smaller sites meet. Both normally work through a supplier or an aggregator and pay for delivery. Income is not guaranteed and depends on the site's size and connection, so no figure is published here.

No. A battery can charge from the grid when electricity is cheap and discharge when it is expensive, with no solar involved. If you do have solar, a battery lets you use more of what you generate on site rather than exporting it, and export rates for businesses are usually lower than the price of the electricity you import.

It can. A battery that discharges at your peak reduces what the site draws from the network at that moment, which can let you add load without raising your agreed capacity. Whether that avoids reinforcement depends on the network operator's terms and on how your peak behaves, so ask your operator and check the shape of your half-hourly demand before relying on it.

Large lithium batteries carry a fire risk that has to be designed for, as with any stored energy. Safety rests on the cells, the battery management system, the enclosure and the installation, and the relevant references include the IET Code of Practice for Electrical Energy Storage Systems, Chapter 57 of BS 7671:2018+A4:2026, IEC 62619 for the cells and IEC 62933-5-2 for the system. Ask any supplier for the design basis, the standards the system is assessed against, and how your insurer has been involved.

It depends on the product, the number of cycles it does and the warranty terms, so ask for the guaranteed energy throughput or cycle count, the capacity guaranteed at the end of the warranty, and the conditions that void it. As a planning benchmark only, the US National Renewable Energy Laboratory's commercial battery model assumes about one cycle a day over a 15-year life.

No. HMRC applies the zero rate to batteries installed in residential accommodation or in buildings used solely for a relevant charitable purpose, from 1 February 2024 to 31 March 2027, with supplies reduced-rated after that. A battery at business premises is standard-rated at 20%, which a VAT-registered business can normally reclaim, subject to partial exemption.

A battery is plant and machinery, so the Annual Investment Allowance gives a 100% deduction in year one on up to £1 million a year of qualifying spend, for companies, sole traders and partnerships of individuals. Above £1 million a year, a company claims the 50% first-year allowance on special-rate spend, which is how this site treats a battery, as HMRC treats solar panels; the rest is written down at 6% a year (see our tax guide). Our tax guide sets out the sources.

Two numbers set it: power in kW, which is how much peak you want to remove or back up, and energy in kWh, which is that power multiplied by the hours it must run. Duration is energy divided by power, so 250 kWh at 125 kW is a two-hour battery. Both come from your half-hourly data rather than from an annual total.

The timetable depends on the equipment lead time, the installation itself and, above all, the grid connection process, which the network operator controls. Ask each bidder to separate the dates they control from the dates the network operator controls, and start the connection application early.

Often, yes. A battery can usually be added to an existing array either AC-coupled, which works with most inverters, or DC-coupled, which depends on the inverter. A change to the site's export capability can need a notification or application to the network operator, so check your existing G98 or G99 registration with your installer.