Commercial Solar Panels in the UK

A Practical Business Guide for 2026

Running a business has never been cheap. Energy prices wobble. Overheads creep. Margins get squeezed from all sides.

Commercial solar panels are one of the few upgrades that flip that script. They cut costs, stabilise energy spend and quietly pay for themselves while you get on with running the business.

This guide explains how commercial solar works in the UK, what it costs, what you can save and whether it makes sense for your building.

Brought to you by Optimum Electrics, specialists in commercial electrical and renewable installations.

Why businesses choose solar panels

Most UK businesses use the bulk of their electricity during daylight hours. Offices, workshops, warehouses, retail units. That timing lines up perfectly with solar generation.

Which means less imported electricity. Lower bills. Faster payback.

The main reasons businesses go solar:

Strong return on investment

Commercial solar systems typically last 25 years or more. Over that lifespan, savings often run into tens or even hundreds of thousands of pounds.

A 20kW system can save around £4,500 per year. In many cases, the system pays for itself within four to five years. After that, it is largely free electricity.

Protection from rising energy prices

Solar lets you lock in a portion of your energy costs upfront. No surprises. No sudden tariff hikes.

Add battery storage and that protection gets stronger.

Income from surplus electricity

If your system produces more electricity than you use, the excess can be exported to the grid through the Smart Export Guarantee. Not huge money, but a useful extra return.

Lower carbon footprint

Every kilowatt-hour generated by solar reduces reliance on fossil fuels. For many businesses, this supports sustainability targets and net zero commitments.

Reputation and credibility

Customers notice. Clients notice. Solar panels send a clear signal that your business takes environmental responsibility seriously.

How much do commercial solar panels cost?

For small to medium-sized UK businesses, commercial solar installations typically range from £16,000 to £60,000, excluding VAT.

The final cost depends on roof size, system capacity, access requirements and whether battery storage is included.

Typical system costs

System size	Business type	Installed cost	Break-even	Estimated ROI
10kW	Small offices, salons	£13,000 to £15,000	5 to 6 years	16 to 18%
20kW	Medium businesses	£16,000 to £30,000	4 to 5 years	15 to 28%
50kW	Refrigeration, workshops	£33,000 to £60,000	3 to 6 years	19 to 36%
60kW	Equipment-heavy sites	£39,000 to £75,000	3 to 5 years	19 to 36%
80kW	Large commercial units	£50,000 to £100,000	3 to 6 years	24 to 48%
100kW	Warehouses, supermarkets	£60,000 to £120,000	2 to 5 years	22 to 45%

Figures are indicative. Real savings depend on usage patterns and electricity tariffs.

How much electricity do businesses actually use?

Most small to medium-sized businesses consume between 30,000 and 50,000 kWh per year.

That is roughly 2,500 to 4,200 kWh per month.Offices sit at the lower end. Supermarkets and food storage sit much higher.

Your energy bill holds the clues. Monthly consumption and cost per kWh determine how quickly solar pays back.

What makes up the installation cost?

Commercial solar is more than panels alone. A typical system includes:

• Solar panels

• Inverters

• Mounting systems

• Electrical infrastructure

• Monitoring and energy management

• Optional battery storage

• Labour and commissioning

Approximate cost breakdown

Component	Share of total cost
Solar panels	25 to 40%
Inverters and batteries	10 to 20%
Mounting systems	10 to 15%
Electrical works	5 to 10%
Labour	15 to 20%
Monitoring and meters	5 to 10%

Larger systems benefit from economies of scale. Cost per kilowatt drops as system size increases.

Maintenance and insurance

Solar panels are low maintenance by design.

• Annual servicing usually costs £100 to £200

• Many issues are picked up early through monitoring software

• Panels require minimal cleaning in the UK climate

Insurance is typically added to an existing commercial policy. Costs vary but often fall between £10 and £20 per month, depending on system size.

Grants and financial incentives for businesses

There are currently no direct UK government grants offering free commercial solar installations. However, several incentives still apply.

Smart Export Guarantee

Businesses exporting excess electricity can earn between 5p and 15p per kWh, depending on supplier and contract terms. A smart meter and MCS certification are required.

Annual Investment Allowance

Solar installations qualify for capital allowances. Businesses can deduct the full cost of the system from taxable profits, subject to limits.

Industrial Energy Transformation Fund

Available to large energy-intensive businesses. Supports decarbonisation projects, including solar.

Local authority schemes

Some councils and regional bodies offer funding or low-interest finance. Availability varies by area.

How much can commercial solar save?

Savings scale with system size.

System size	Estimated annual savings	Payback period
10kW	£2,400	5 to 6 years
20kW	£4,600	4 to 5 years
50kW	£11,900	3 to 6 years
60kW	£14,300	3 to 5 years
80kW	£24,000	3 to 6 years
100kW	£27,000	2 to 5 years

Once installed, running costs are close to zero. Every additional unit generated is pure saving.

Advantages of commercial solar PV

• Long-term energy cost reduction

• Predictable operating expenses

• Lower carbon emissions

• Improved brand image

• Increased property value

• Optional battery backup for resilience

Solar turns electricity from a liability into an asset.

Disadvantages to consider

Solar is not perfect. It does require thought.

• High upfront investment

• Roof or land space requirements

• Planning permissions in some locations

• Longer payback for very small systems

These issues are usually manageable with proper design and professional advice.

Do you need planning permission?

In many cases, commercial solar falls under permitted development.However, permission is required if:

• The building is listed

• The site is in a conservation area

• Panels significantly alter roof appearance

• You are expanding an existing system

Always check before installation. A competent installer will handle this process for you.

Are commercial solar panels worth it?

For most UK businesses, yes. Unequivocally.

While upfront costs can look daunting, the numbers tell a different story. High ROI. Short payback. Decades of reduced energy costs.

Add in sustainability benefits and future-proofing against energy volatility, and solar becomes less of a gamble and more of a strategic move.

Ready to explore solar for your business?

Optimum Electrics (a leading solar company) works with businesses across the UK to design and install commercial solar systems that actually make financial sense.

No guesswork. No over-specification. Just systems built around how your business really uses energy.

If you want clear advice, realistic projections and a system that delivers, it starts with a conversation.