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First conversation
What the site is, who owns it, how it uses electricity, and what you want the battery to do.
Commercial battery storage, with solar or without
Commercial battery storage holds electricity on your site so the site can use it when it needs it. A battery energy storage system, or BESS, stores surplus solar, charges from the grid in off-peak periods where your tariff allows, and runs the site at its busiest times. We design, install and maintain commercial batteries for businesses and farms across the UK, sized from your half-hourly data, and we handle the network operator's approval.
What is commercial battery storage?
A battery on a business site sits between your supply, your solar if you have it, and the building. It fills up when there is spare electricity on site or when electricity is cheaper to buy, and the site draws on it later.
It is described by two numbers: its power in kW, which is how fast it can charge and discharge, and its usable energy in kWh, which is how much it can hold. Both are set from your site, not picked from a range.
The first thing we ask for is not a product brochure. It is your half-hourly consumption data, which your supplier can provide, or failing that your last twelve months of bills. That shows when you use power, when any solar produces it, and how far apart the two are.
We will tell you in writing if a battery does not make sense for your site.
A battery is sized from your data and your connection, not from a brochure.
How a commercial battery runs across a day
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jobs, set for your siteEvery battery we fit runs to an operating profile set for the site. Across a typical day it does three jobs, in the order your demand, your solar and your tariff call for.
- 01Storing surplus solar. In daylight your panels serve the building first. What the site cannot use goes into the battery for later in the day, instead of being exported cheaply.
- 02Charging off-peak. Where your tariff allows, the battery charges from the grid in lower-cost periods and runs the site when prices are higher.
- 03Discharging at peak times. At your busiest times, such as evening floodlights, a kitchen at full tilt or a row of EV chargers, the battery serves the site and lowers the peak it draws from the grid.
- 04Adjusted as things change. The control settings are set against your tariff, the weather and how full the battery is, and changed when the way the site runs changes.
Fire safety, location and the grid connection are assessed for every battery. Adding storage changes your connection, so we handle the network operator's approval as part of the job.
Battery storage with solar, or without
We fit commercial batteries alongside new solar, add them to existing commercial solar, or install them on their own. The battery does a different job depending on whether the site has panels.
With solar, new or existing. The battery keeps the surplus your panels make at the sunniest times for later in the day. If your solar is already up, we add the battery to it, after checking the existing inverters and what your connection was originally approved for.
Without solar. Where your tariff allows, the battery charges in lower-cost periods and runs the site when prices are higher. It does not rely on the sun, so it works the same way in January as in June.
If you are planning solar as well, we design the two together, so the battery, the inverters and the grid application are worked out once. More on commercial solar.
How we size a commercial battery
Two things set the limits: your import capacity and your export permission, both fixed by your connection. Within them, the size follows your energy profile: when the site uses power, when any solar produces it, and the loads that set the peaks, such as refrigeration, floodlights or EV charging.
A battery that is too small does little, and one that is too big costs more and works no harder.
What to send us
- At least 12 months of electricity bills, or half-hourly data if you have it
- Your MPAN, the supply number on your electricity bill
- Your import capacity and export permission, if you know them
- Details of any existing solar or other generation on the site
- Roof or site plans and photos, and any access constraints
- Your operating hours and major loads, such as refrigeration or EV charging
- Whether you own or lease the building
Missing some of it? Send what you have and we will tell you what else we need.
Which businesses it suits
The test is when your site uses electricity, and what your connection and tariff allow, not the sector.
Car dealerships and garages
Showrooms, workshops and forecourts with long opening hours, and EV charging that is fast becoming one of the biggest loads on site. Demand carries on after the panels stop producing.
Golf, rugby and sports clubs
Clubhouses, kitchens, bars, changing rooms and floodlights, with year-round running costs and evening peaks, when training and matches start after the panels have stopped producing.
Commercial premises
Owners, landlords and occupiers of offices, warehouses, factories and industrial units, with daytime loads from lighting, machinery, chargers and refrigeration. Tell us whether you own or lease the building, because it decides who agrees to the work.
Farms
Barn roofs that generate most around midday, and high loads from milking, refrigeration, grain drying and irrigation that do not all fall at midday.
Solar for farmsIf your site is not on that list, it may still work. Send us the data and we will tell you.
How we design, install and maintain it
Assess, design and approve, deliver and hand over, then look after it: one company from the first look at your data to the maintenance visits afterwards.
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Data and feasibility
From your bills or half-hourly data, your MPAN, your import and export capacity and any existing generation, we size the battery in kW and kWh and check whether the connection can take it.
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Technical survey and design
A survey of the site, where the battery can safely go, the space and fire protection it needs, cable routes and the electrical design.
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Grid approval
Adding storage changes your connection. On almost every commercial site that means a G99 application, approved by the network operator before installation. We prepare and submit it.
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Contract
The scope, the price, the programme and who is responsible for what, in writing, before anything is ordered.
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Procurement and installation
Equipment bought direct from the manufacturer to the approved design. Risk assessments and method statements before work starts, £10 million liability cover, and one short, planned interruption for the electrical connection, agreed with you in advance.
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Commissioning and handover
Electrical testing, protection settings, commissioning and certification. Monitoring is set up, your staff are shown how the system works, and you receive the documentation and test results your insurer or landlord will ask for.
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Monitoring and maintenance
We monitor performance and system health, and look after the battery under a planned maintenance agreement, alongside any solar on the site.
No step is skipped on a small site. A clubhouse battery gets the same paperwork as a warehouse.
G99 connection, fire safety and standards
Three things are settled before a battery is ordered.
The grid connection. The connection rules treat a battery as generation: EREC G98 and G99 both say so, and the 16 amps per phase limit counts every inverter on the supply, the battery's included. Above that limit it is a G99 application, approved before installation. Issue 2 of G99 added requirements for batteries commissioned from 1 March 2026, so the equipment has to meet the current issue. Where the local network cannot take your full export, an export-limitation scheme designed to G100 keeps the project viable. Our G98, G99 and DNO guide explains the thresholds.
Fire protection and space. Where a battery can safely sit, how it is protected, and how much room it needs around it are part of the design, not a decision for the day. The industry reference is the IET Code of Practice for Electrical Energy Storage Systems, and MCS's battery standard requires installers to follow it.
MCS, and batteries bigger than 50 kW. DB Energy is MCS certified for solar PV and battery storage (certificate NIC-601172). MCS's Battery Installation Standard, MIS 3012, covers battery systems with a maximum power output of up to 50 kW. Many commercial batteries are bigger and sit outside the scheme, so for those our MCS certificate tells you about us, not about that battery. Every battery we fit is installed to the wiring regulations, BS 7671, and to the network operator's connection rules.
Accreditations
DB Energy is MCS certified for solar PV and battery storage (certificate NIC-601172) and a member of RECC (registration 00075024). Our electrical work is carried out under NICEIC registration, we are CHAS accredited (29017638), and our workmanship guarantee is insured through IWA.
MCS certified
RECC member
NICEIC registered
CHAS accredited
IWA insurance-backed guaranteeMonitoring and maintenance after installation
See our commercial O&M serviceA battery is an electrical asset that will sit on your site for years, so it is monitored and maintained, not just commissioned.
We set up monitoring of performance and system health at handover, and show your staff how the system works.
Maintenance visits cover visual and functional checks of the battery system and of the inverters, isolators and distribution equipment around it, with a performance review and fault investigation where needed. The battery is looked after under the same planned maintenance agreement as any solar on the site, and the visits are set out in that agreement.
Commercial battery storage questions
What is a commercial battery?
A commercial battery, or battery energy storage system (BESS), stores electricity on a business site so the site can use it later. It holds surplus solar, charges in lower-cost periods where the tariff allows, and serves the site at its busiest times. It is sized in kW of power and kWh of stored energy, from the site's own consumption data.
Can a commercial battery work without solar panels?
Yes. We install commercial batteries on their own as well as with solar, and without panels the battery charges in lower-cost periods where your tariff allows and runs the site when prices are higher. Whether that suits your site depends on your tariff and when you use electricity, which your half-hourly data shows.
Can a battery be added to existing commercial solar?
Yes, including solar we did not install. We first check the existing inverters and what the site's connection was originally approved for, because adding storage changes the connection and the network operator has to approve it or be told about it.
Does a commercial battery need G99 approval?
Almost always. The connection rules treat a battery as generation and the 16 amps per phase limit counts every inverter on the supply, so most commercial batteries need a G99 application approved by the network operator before installation, with an export limit designed to G100 where the network cannot take your full export. We prepare and submit the application as part of the job, and our G98, G99 and DNO guide explains the thresholds.
Is a commercial battery (BESS) safe?
Safety is designed in, not decided on the day: fire protection, the space around the battery, its location and the grid connection are assessed for every battery we fit. We design to the IET Code of Practice for Electrical Energy Storage Systems, which MCS's battery standard requires installers to follow, and tell you in writing where a battery can go on your site and where it cannot.
What size commercial battery does our site need?
It is set by your import capacity and export permission, which fix the limits, and by your energy profile: when the site uses power, its biggest loads and any solar it has. From your half-hourly data or last twelve months of bills we size the battery's power in kW and its usable energy in kWh, because one that is too small does little and one that is too big costs more and works no harder.
How much does a commercial battery cost?
We do not publish a price, because it depends on the battery's capacity and power, where it goes, and how much work the grid connection needs. We give you a written price as part of the feasibility assessment, from your own data, before you commit to anything.
Is DB Energy MCS certified for battery storage?
Yes, DB Energy is MCS certified for solar PV and battery storage, certificate NIC-601172. MCS's battery standard, MIS 3012, covers battery systems up to 50 kW, so larger commercial batteries sit outside the scheme. Those are installed to the wiring regulations, BS 7671, and the network operator's connection rules.
Who maintains a commercial battery after it is fitted?
We do, under a planned maintenance agreement that also covers any solar on the site, with monitoring set up at handover. Visits cover visual and functional checks of the battery, inverters, isolators and distribution equipment, with a performance review and fault investigation where needed.
Find out whether a battery suits your site
Send us your half-hourly data or your last twelve months of bills, and a photo or address for the site. We will come back to you within two working days with a view on whether a battery makes sense, what size, where it could go, and whether it is worth a site visit. If it is not, we will say so.