What Size Of Solar Battery Does My Business Requires? – Complete Guide 2026 

A UK business would be smart financially to switch to using solar power. In order to reap the maximum benefits of having a solar panelling system, it is essential to select the appropriate size of the battery. It influences your savings, backup capacity and long term ROI which means you cannot make a guess.  

Whether you have a small workshop, a store, or a big commercial location, this guide is what you need to know how to estimate the size of a battery, what affects its size, and how to use batteries with the contemporary solar panels installation, inverter, mounting system and storage system.  

The Concept of Solar Battery Capacity 

The size of solar batteries is measured in kilowatt-hours (kWh) total power that they are capable of storing.  

It was imagined that the battery resembles a wallet in the form of a water tank:  

Bigger tank has more energy 

• Too small = runs out fast.  
• Too large = wasted investment.  

Commercial solar systems that are currently in use typically use panels that are paired with:  

• Solar panel and battery kits  
• Smart solar inverters  
• Solar panel optimizers  
• Systems of solar panel mounting.  
• bird guard of solar panel and mesh (necessary).  

This combination guarantees the efficiency and safety of the whole system.  

How does your business consume a lot of energy?  

The first step is to find your battery size based on your daily electricity use, as indicated in the energy bills in the kwh unit.  

Typical UK business usage:  

Important Factors Which Determine Battery Size

Your Operating Hours 

Should the workload be done majorly during the day, you require a smaller battery since panels already cover work.  

You will require bigger storage when your business operates beyond that of sunset. Solar power is now being utilised in many UK businesses to:  

• Sheds  
• Outbuildings  
• Vehicle charging  
• Garden tools  
• Pumps  
• Solar AA battery chargers  
• House number signs that are solar powered.  

Cases of mini solar battery kits are also applicable to these small setups.  

Backup Power Requirements

Do you want backup for:  

• 1 hour?  
• 4 hours?  
• Full‑day emergency backup?  

A company that has to back up machines, POS machines, or refrigeration on a per-need basis should have a bigger battery bank.  

Solar Panel System Size

Greater size solar panel systems (greater wattage or larger panels) produce more surplus electricity, that is:  

• You are able to charge big batteries.  
• You pay less regarding electricity bills.  
• You develop a greater freedom of the grid.  

Battery works are also enhanced by proper size of solar panels, roof mount and optimizers.  

Budget & Grant Eligibility

The type of the battery you choose might be determined by:  

• Total solar panel cost  
• Solar battery prices  
• Eligibility of your business to UK solar panel grants.  

Solar installation options and Solar installation kits are available in large format as well as mini formats.  

Solar panels servicing and maintenance requirements 

It is better to have a balanced layout than spend too much of the money on storage that will not be utilised.  

Recommended Battery Sizes of various UK Businesses

Small Businesses (Offices, Studio, Clinic) 5000–10000 W  

Ideal in storing power during the day and use during the evening.  

1. Shops, Cafés, Salons – 10 kWh to15 kWh.

A solar panel is often combined with a solar panel powering shed or just a solar panel kit in the UK which includes a battery and an inverter.  

2. Warehouses, Workshops – 15 kWh to 30 kWh  

Machine, motor and heavy load tools.  

3. Industrial Units or Manufacturing– 30kwh to 100kwh+  

Normally involves several battery stacks, sophisticated inverters, solar panel roof mount, and series and parallel wiring.  

How to Just Work out the Ideal Battery Size 

Use this simple formula:  

Daily Usage/Percent of Energy You desire held in battery = Daily Use by the Percent you would like stored in battery.  

Sample A 50 percent storage unit of a shop with this consumption 30 kWh/day would require:  

30 × 0.5 = 15 kWh battery needed.  

When your panels single on a flat roof or garage roof, or you are within a conservation region, to use battery storage is possible however there might be restrictions in using panels.  

Should My Business have solar panels but do I really need a battery?  

Not in every case, but to a large extent, because of:  

• Peak tariff cost avoidance  
• Blackout protection  
• Using solar at night  

Consideration The lessening of grid dependency 

Businesses that do not begin with a battery usually get upgraded at a later stage.  

Advantages and Disadvantages of solar battery business  

Advantages  

• Lower electricity bills  
• UPS in the case of power failure.  
• Better ROI on solar panels  
• Supports EV charging  
• Instals solar panel fence, sheds, outbuildings or carports.  

Disadvantages

• Higher upfront cost  
• Limited lifespan  
• May either needs to be serviced or premeditated.  

Key Takeaways  

• The size of the solar batteries varies based on the amount of everyday energy you consume, the amount of time your business operates, and the reserve power you require.  
• Battery storage of 5000 watts- 20000 watts (5-20 kWh) is needed by most UK SMEs.  
• Long working hours or heavy machinery load of businesses might require 20kwh-100kw.  
• The battery kit is paired to a solar panel and increases the savings to a greater extent during peak tariff times.  
• Solar panels can be applied to flat roofs along with garage roofs, sheds and outbuildings using solar batteries.  

Conclusion  

Selecting the appropriate size solar battery to your business can achieve a lot of saving, enhance energy self reliance, and the worth of your solar panel set-up. Whether it is a small office arrangement or an industrial system, the optimal battery size is based on how much you use on your daily basis, the number of hours you are going to operate and whether you are planning to expand in the future.