Could commercial solar be a sound investment?

The Electricity Authority reports that power prices for households and small businesses increased by an average of 6.8% during the first half of 2026, following an 8.0% increase in 2025. Not every customer was affected, but the overall direction makes electricity worth reviewing as a controllable business cost.

For some businesses, commercial solar may be more than an environmental decision. It can be a long-term investment in lower operating costs and greater certainty, particularly when a business owns its premises, has suitable roof space and uses a large share of its electricity during daylight hours.

The important question is whether the numbers stack up for your business.

Start with your actual electricity use

Before considering a solar system, look at at least 12 months of electricity use.

This gives you a clearer picture of how much power your business consumes, how usage changes throughout the year and when during the day you use the most electricity.

Businesses that use a significant amount of power during daylight hours may be better placed to use the electricity generated by solar directly, rather than exporting excess generation back to the grid.

That can make a significant difference to the financial case.

Look at the property

The building itself also needs to be suitable.

Consider the condition, size and orientation of the roof, along with any shading or structural issues that could affect installation or generation.

It is also worth thinking about how long you expect to remain in the property.

If you own the building and expect to operate from it for many years, you may have more time to receive the benefit from the investment. If you are likely to relocate or sell sooner, that should form part of the calculation.

Understand the real cost and expected return

A commercial solar proposal should give you a clear picture of:

• the total installed cost
• the expected annual generation
• how much of that electricity your business is likely to use
• the expected savings
• the estimated payback period
• maintenance requirements
• warranties and expected system life
• whether battery storage is needed

The payback period is only useful if the assumptions behind it are realistic.

It is worth asking what electricity-price assumptions have been used, how future generation has been estimated and what happens if your electricity use changes.

Consider how you will fund it

Solar may be purchased outright or funded in other ways, depending on the provider and the project.

The best option will depend on your cash position, financing costs and wider plans for the business.

An outright purchase may require more capital upfront but could provide a different long-term return from a financed or leased arrangement.

As with any major investment, it is important to look beyond the initial payment and understand the total financial impact over time.

Think about future electricity needs

Your current electricity use is only part of the picture.

If you are planning to expand production, add equipment, increase operating hours or introduce electric vehicles, your future electricity requirements may look quite different.

Those changes should be considered before deciding on the size and structure of a solar system.

Battery storage may also be useful in some situations, but it adds cost to the project and should be assessed based on what your business actually needs it to achieve.

Solar will not suit every business

Commercial solar is not automatically a good investment.

The return depends on the building, the way the business uses electricity, the system size, installation cost, finance arrangements and how long you expect to remain at the property.

However, with electricity prices rising and solar-system costs becoming more competitive, it can be worth running the numbers rather than dismissing it.

The best approach is to treat solar like any other significant business investment: understand the costs, test the assumptions and consider how it fits into your wider business plans.

How we can help

If you are considering commercial solar, we can help you understand the numbers, test different scenarios and assess what your business can realistically afford to invest in.

We can also help you consider the cash-flow, accounting and tax implications before you make a commitment.

The aim is not simply to decide whether solar sounds like a good idea, but whether it is a sound investment for your business.