Knowledge Centre · Cost guide

What does commercial solar cost in South Africa?

A grid-tied commercial rooftop installation costs from about R10,400 per kWp at 50 kWp down to R6,700 per kWp at 1 MW, excluding VAT: roughly R520,000 to R6.7 million installed. Focal Energy’s own indicative figures, for grid-tied solar only, batteries priced separately.

By Jonathan de Vrye, BSc Eng — Managing Director, Focal Energy · Updated 19 August 2026 · All figures exclude VAT and are budget indications, not quotes.

What is the going rate for a commercial system?

These are Focal Energy’s own indicative budget figures for a standard grid-tied commercial rooftop installation, excluding VAT, with no battery storage. The rate per kWp falls by roughly a third between 50 kWp and 1 MW: economies of scale in procurement and installation, fixed costs (design, sign-offs, registration, mobilisation) becoming a smaller share of the project, and a lower EPC margin at larger scale.

System size	Indicative total	Rate per kWp
50 kWp	R520,000	R10,400
100 kWp	R870,000	R8,700
200 kWp	R1,570,000	R7,850
500 kWp	R3,620,000	R7,240
1,000 kWp	R6,700,000	R6,700

Budget indications excluding VAT, not a quote and not a price list: every roof carries its own structural, access and grid-connection conditions, and intermediate sizes sit between the bands.

Grid-tied means no load-shedding protection. A grid-tied system operates together with the utility supply and is required to switch off when the grid fails. During load shedding it stops generating until supply returns. Riding through outages needs battery storage, which is sized and priced separately against the loads that must keep running.

What is not included in the base cost?

The items below are not included in the figures above. Each one adds to the overall cost where the site requires it, or where you choose to include it.

Waterproofing: Roof penetrations must be sealed and flashed, and sheeting that already leaks is repaired before an array is fixed over it. Remedial waterproofing is real money on older roofs.
Lightning protection: The earthing and surge-protection scope that follows the lightning risk assessment. What the assessment finds determines what must be installed.
Walkways: Permanent access routes over the sheeting so that maintenance staff never walk on panels or brittle roof surfaces. Priced by roof layout, required for safe operation.
Roof access: How people and equipment reach the roof: existing stairs and hatches, or scaffolding, mobile platforms and crane time. Labour cost scales with the building, not the kilowatts.
Inverter housing: Inverters need a ventilated, secure, shaded home. An existing plant room is cheap; a purpose-built enclosure is not.
Mounting structure type: Different roof sheeting profiles and pitches take different mounting systems, and flat roofs need ballasted or penetrating frames. The structure is where roof-specific engineering starts.
Generator integration: Where a site runs standby generation, the solar and battery system must be interlocked with it so the sources never fight. Controls and changeover work sized to the site.

How does that compare with published market guidance?

Published market guidance for South African commercial installations in 2026 sits at roughly R12,000 to R18,000 per kW installed, before battery storage. Those are third-party published ranges, not Focal figures; we publish ours above so the comparison is yours to make.

System size	Published market range	What moves it
20–50 kWp	R400,000 – R900,000	Fixed costs — design, sign-offs, registration, access — spread over few kilowatts, so the rate per kW sits at the top of the range.
50–150 kWp	R900,000 – R2,500,000	The band where most single-tenant commercial roofs land. Scale starts to work in your favour.
150 kWp and above	R2,500,000 upwards	Rates trend toward the lower end per kW, but grid connection, MV work and structural strengthening become the swing factors.

Why check the DC:AC ratio before comparing quotes?

Because solar is priced in rand per kWp (or per Wp), and kWp measures only the DC side: the panels. The AC side of the system, the inverters, cables, protection and switchgear that actually deliver the power, is not separated out in a per-kWp price, when it should be. An installer can put 130 kWp of panels on 100 kW of inverter capacity: the AC hardware is then spread over more kWp, and the price per kWp looks better without the AC side getting any bigger.

Some installers push the DC:AC ratio as high as possible for exactly that reason: it dilutes the AC cost and flatters the headline price. Always check the DC:AC ratio on a quote, and ask the bidder to justify it against your load profile, so a better-looking rate per kWp is not hiding an under-specified AC side.

A ratio pushed too high has real costs. Generation above the inverter’s AC rating is clipped and lost. The whole AC chain, from the cables and breakers to the inverter itself, runs closer to its limits for more hours of the day, which ages it faster and brings replacement costs forward. And in certain circumstances, operating outside the manufacturer’s specified ratio can void warranties. The right ratio is a design output of your load profile, not a pricing lever.

What is actually in the price?

A complete commercial installation is roughly a third equipment and two thirds engineering, labour, compliance and connection. When quotes diverge, it is almost never the modules — it is which of the items below a bidder has left out.

Modules, inverters, mounting: The visible plant, and usually the smallest source of price variance between serious quotes. Module prices are commodity-driven; the mounting system is where roof-specific engineering starts.
DC and AC reticulation: String cabling, combiner boxes, AC cabling to the point of connection, protection devices, isolators and labelling. Priced by distance and by volt-drop limits, not by system size — a plant room 200 m from the array costs materially more than one below the array.
Structural engineering sign-off: A professional assessment that the roof carries the additional dead and wind load. On older sheeting or long-span purlins this can trigger reinforcement, which is a genuine cost and a genuine reason a cheap quote is cheap.
Electrical professional engineer sign-off: Design certification by a registered professional — required for the supply authority's embedded-generation application and for insurers.
Certificate of Compliance (COC): The installation certificate under the national wiring code. Without it the installation is not legally compliant and an insurer has grounds to decline.
Lightning risk assessment: A rooftop array is an extended metallic structure on a Highveld roof. The assessment determines earthing and surge protection — cheap to do, expensive to skip.
Embedded-generation registration: The application to the supply authority, with single-line diagrams, approved-equipment evidence and grid protection settings. Often a meter change too.
Monitoring and metering: Inverter-level monitoring at minimum. Independent check metering — a meter that is not the inverter's own — is what makes performance claims auditable rather than self-reported.
Commissioning and handover: Testing, protection-setting verification, as-built documentation, warranties and operating instructions. The paperwork is what a future buyer, bank or insurer will ask for.

Why do two quotes for the same roof differ by 30–50%?

Because a quote is four sets of decisions stacked on top of each other, and bidders make them differently:

1
Scope
Which of the base-cost exclusions above are in, which are out, and what has been quietly left off the page (registration, sign-offs, structural work) to win on price. The cheapest quote is usually cheap because of what it does not say.
2
Specification
The DC:AC ratio above, the equipment tier, and whether the AC side is sized for the duty or diluted to flatter the rate per kWp. Two systems with the same kWp on the cover page can be very different machines.
3
Site conditions
The table below: what this specific roof, distribution board and point of connection force on the design. Most of it is invisible from a satellite photograph, which is why desktop quotes diverge from surveyed ones.
4
Margin and risk
Who carries performance risk after handover, what the warranties actually cover, and whether anyone will still be answering the phone in year ten. Priced differently by businesses that intend to be there.

The site conditions are the part no bidder controls, and they move the price more than the choice of module brand:

Factor	Cost	Why
Battery storage	↑	The single largest swing item. Storage can cost more than the entire PV plant it supports, and it is the usual explanation when two quotes differ by half.
Roof condition and age	↑	Sheeting near the end of its life should be replaced before a 25-year asset is bolted to it. Doing it afterwards means dismantling the array.
Structural strengthening	↑	Where the engineer requires purlin or truss reinforcement. Common on older industrial sheds and almost always omitted from the cheapest quote.
Height, access and edge protection	↑	Scaffolding, mobile platforms, fall arrest and crane time are labour costs that scale with the building, not with the kilowatts.
Distance to the point of connection	↑	Copper is priced by the metre and volt-drop limits force a larger cross-section over distance. A long run can cost more than a string of modules.
Existing switchgear and boards	↑	Older distribution boards frequently need replacement or upgrade before a generation source can be connected safely.
MV rather than LV connection	↑	Connecting at medium voltage brings switchgear, protection and metering of a different order to an LV tie-in.
Export limiting or zero export	↑	A controller and metering to hold generation behind the meter. Modest in cost, and often the condition of approval.
System size	↓	Design, sign-offs, registration and mobilisation are largely fixed. Spreading them over more kilowatts is the main reason large systems cost less per kW.
DC:AC ratio	±	Oversizing the array relative to the inverters lifts morning and afternoon output cheaply, at the cost of clipping the summer midday peak. The right ratio depends on the load profile, not on a rule of thumb.
Module and inverter tier	±	Equipment choice moves price less than most buyers expect. What it moves is warranty terms, degradation rates and whether the manufacturer will still exist to honour either.
Operations and maintenance	±	Not capital cost but lifetime cost. Cleaning, inverter servicing, monitoring, reporting and eventual inverter replacement belong in the model, not in a footnote.

The practical defence: issue one scope of works to every bidder and require the same line items back, with the DC:AC ratio and the exclusions stated. Quotes that looked 50% apart usually land within 15% of each other once they describe the same job. The spread that remains is margin and risk appetite, which is a legitimate difference worth understanding rather than a trap.

What does battery storage add to the cost?

Storage is the single largest variable in a commercial energy budget, and it is usually the explanation when one quote is half another. Sizing follows purpose, and it swings the cost more than anything else: a battery that carries a site through a two-hour outage is a vastly different machine, and a vastly different price, from one that must ride through eight hours. Decide what the battery is for first; the size and the cost follow. It should be justified on what it is being asked to do, not added by default.

Where a site carries a demand charge and its highest half-hour falls outside generation hours — a winter morning start-up, for instance — solar alone cannot touch it, and storage sized to shift that peak can carry its own cost. (What those charges actually are on a Johannesburg account is in our City Power tariff reference.) Where the objective is continuity through an outage, the case is operational rather than financial and should be argued that way. What does not work is sizing storage without interval meter data: the half-hourly load profile is what tells you how many kilowatt-hours you need and for how long.

What is the benefit of the Section 12B allowance?

Section 12B of the Income Tax Act is South Africa’s capital allowance for renewable generation assets. It accelerates depreciation on the qualifying asset, which can lift the after-tax return well above the pre-tax figure a proposal shows.

Less well known: the allowance applies to the generation asset as a whole, not just the panels. Waterproofing and the other electrical and civil upgrades associated with the solar project can be included under 12B where they are part of the project and wrapped up in one quote. That is worth knowing before splitting the work across separate contractors and separate invoices.

The rules and rates change with the national budget, so the treatment for a specific business in a specific tax year belongs with a tax adviser rather than a proposal PDF. The point for budgeting is simply that the pre-tax return on a quote is usually the conservative figure, not the optimistic one.

What if the capital isn’t available?

Then the question changes from “what does it cost” to “what does the energy cost”, which is the more useful question anyway.

Under a power purchase agreement, the system is funded and owned by the provider and the business buys the generation at an agreed rate per kWh — no upfront capital, and asset performance risk sits with the owner rather than the tenant of the roof. Partnership structures sit between that and outright purchase. The comparison that matters is the same in every case: the rate per kWh you end up paying, against the tariff it displaces, over the life of the asset.

Focal Energy’s funding options cover outright purchase, PPA with no upfront capital, and partnership.

Common questions

What does commercial solar cost per kW in South Africa?

Focal Energy's indicative budget figures for a standard grid-tied commercial rooftop installation, excluding VAT and without batteries, run from about R10,400 per kWp at 50 kWp to R6,700 per kWp at 1,000 kWp: roughly R520,000 at 50 kWp, R870,000 at 100 kWp, R1,570,000 at 200 kWp, R3,620,000 at 500 kWp and R6,700,000 at 1 MW. Published 2026 market guidance clusters higher, roughly R12,000 to R18,000 per kW installed. Treat any per-kW number as a budgeting shape rather than a quote: the same building can attract honest quotes 30–50% apart depending on roof condition, structural work, distance to the point of connection and whether storage is included.

Will a grid-tied solar system work during load shedding?

No. The prices above are for grid-tied systems, which operate together with the utility supply and are required to disconnect when the grid fails. During load shedding a grid-tied system stops generating until supply returns. Riding through outages needs battery storage or another backup source, sized and priced separately against the loads that must keep running.

Why are solar quotes for the same building so different?

Usually because they are not quoting the same scope. The common omissions are structural reinforcement, roof replacement where the sheeting is near end of life, cabling to a distant point of connection, switchgear upgrades, embedded-generation registration and the professional sign-offs. Ask every bidder for the same line items and the spread narrows sharply.

Is it cheaper to buy a commercial solar system or sign a PPA?

Buying gives the lowest lifetime cost per kWh because there is no financing margin, but it consumes capital and puts asset performance risk on the business. A power purchase agreement requires no upfront capital and shifts performance risk to the provider, at a higher cost per kWh. The right comparison is the PPA rate against the levelised cost of the owned system, both measured against the tariff they displace — not the monthly payment against nothing.

Does a commercial solar system need approval before it can operate?

Yes. A grid-tied commercial system must be registered as small-scale embedded generation with its supply authority before it may run, supported by a single-line diagram signed by a professional engineer, equipment from the authority's approved list, and a Certificate of Compliance for the installation. Requirements and capacity thresholds differ between authorities and change, so they should be confirmed for the specific connection.

Do batteries make financial sense on a commercial site?

It depends on what the battery is being asked to do. Where the site carries a demand charge and its peak falls outside generation hours, storage that shifts that peak can pay for itself. Where the objective is backup during outages, the value is continuity of operations rather than energy savings, and it should be justified on that basis. Storage sized without interval meter data is usually sized wrong.

What ongoing costs follow a commercial solar installation?

Budget for module cleaning at a frequency set by the site's soiling rate, inverter servicing, monitoring and performance reporting, insurance, and inverter replacement once within a 25-year life. These are modest against the energy saved but they are not zero, and a savings model calculated without them is optimistic by construction.

See the published case studies City Power tariffs 2026/27 Glossary Back to Knowledge Centre

See what your site could save.

Tell us your monthly electricity usage and we'll model your consumption and system options against your own tariff. Numbers you can rely on.

Assess your energy opportunity See project results