Alectrona
Commercial guideThe honest answer is that capital cost is survey-led and site-specific, which is why a credible commercial quote starts with the roof rather than a price list.
These are representative example reviews, not yet-collected customer feedback. They are written to illustrate the kind of feedback Alectrona aims to earn and are shown as design placeholders while we gather and verify reviews from our first commercial clients. Alectrona is the commercial solar trading brand of RVTC LTD.
What set Alectrona apart was the documented design pack. We had quotes from three installers, but only Alectrona handed us a full set of drawings, a single-line diagram and a design referencing BS 7671 and the G99 connection process. The whole thing read like an engineering submission rather than a sales brochure. Our M&E consultant reviewed it and signed it off without a single query. That gave the board the confidence to release the capital.
Other firms priced our roof off a satellite image and a desktop guess. Alectrona flew an in-house drone survey, fully insured and flown by a qualified commercial drone pilot, and built a 3D model of the actual roof. It picked up plant, vents and a parapet line that a flat aerial photo had completely missed, which changed the panel layout. I would rather find that out at design stage than on the day the scaffold goes up. The accuracy of that survey is the reason I trusted everything that followed.
As a finance director I was wary of being oversold a system bigger than we could use. Alectrona modelled the array against our actual half-hourly consumption data rather than an annual total, so it is sized to what we genuinely draw on site during the day. They were honest that exporting surplus is worth far less than self-consumption, and built the design around that. The capital case stacked up because the engineering was honest, not because the numbers were inflated.
We were undecided between buying outright, leasing and a PPA. Alectrona laid out all three side by side with the pros and cons of each against our balance sheet, instead of pushing the one that pays them best. They were clear about where a PPA makes sense and where capex wins, and pointed us at our own accountant for the tax treatment. The survey and design took a little longer than I expected, but the thoroughness was worth the wait. Genuinely consultative.
The install crew were tidy and well run, and worked to a clear CDM 2015 plan with a proper site induction and RAMS. What impressed me most was the handover. We received a full commissioning pack with the IEC 62446-1 test results, certification, O&M documentation and an as-built record for our maintenance team. As the people who have to live with this asset for the next twenty years, having that paperwork in order matters enormously. Nothing was left loose.
I expected the usual hard sell and got the opposite. After surveying our site Alectrona told us one roof section was not worth covering because of shading, and that a smaller, well-sited array was the better investment than filling every square metre. There was no commission-driven upselling and no pressure. For a six-figure capital project, that straight talk is exactly what you want from the people advising you. We will be using them again on our second site.
OrientationThis is a plain-English orientation for a finance or facilities director, not formal financial, tax or engineering advice. The cost drivers and standards named here are typical for a commercial rooftop system over 50 kWp; we confirm the specifics, the connection route and the final price for your site from survey.
If you are weighing a rooftop solar system over 50 kWp, the first thing you want is a number. The first thing any honest installer will tell you is that the number depends on your building. Two sites with the same roof area can carry very different costs once the structure, the access and the grid connection are accounted for.
This page sets out what actually drives the capital cost of a commercial PV system, why a blanket “from £X per kWp” headline tends to mislead more than it helps, and how we move from a survey to a single fixed price you can put in front of a board. It is capex-primary throughout, because most businesses buy the system outright or finance the capital cost, and the capital figure is what the return is measured against.
This is a plain-English orientation for a buyer, not formal advice. We confirm the specifics for your site.
The largest single line is usually the equipment: the modules, the string inverters, the mounting structure, the DC and AC cabling, isolators and protection. The equipment is rarely the part that separates one quote from another. The site-specific works are.
The factors that move a commercial price most are:
None of these can be priced from a desktop. They are why the survey comes first.
You will see commercial solar advertised at a single rate per kWp. Treat it with caution. A per-kWp headline assumes a clean, strong, accessible roof with a straightforward grid connection, and it quietly drops everything that varies. The moment the structure needs attention, the scaffold is non-standard, or the DNO returns a connection with conditions, the real figure parts company with the headline.
A figure that looks competitive on a brochure can be the more expensive system once the omitted works appear as variations during the build. We would rather give you one number that holds. That means we do the survey work up front and price the whole job, including the parts a per-kWp rate leaves out, so the figure you approve is the figure you pay.
We start with an in-house, fully insured drone survey that builds a measured 3D model of your roof, so the design works from real geometry: the usable array area, the rooflights, the plant, the parapet edges and any structural span limits. That replaces the desktop estimate that a per-kWp rate relies on.
Alongside the roof, we take your half-hourly consumption data and model generation against it in PV*SOL, so the system is sized to the load your building actually carries rather than to the area on the roof. The structural check, the access plan, the electrical route and the G99 grid-connection position are all confirmed for your site.
From that survey we produce a single fixed price, set out so you can see what it covers. Because a system over 50 kWp sits outside MCS, and MCS is the domestic scheme that does not apply here, MCS is not the assurance. The work is assured by the commercial engineering stack instead: CDM 2015, under which a principal designer and principal contractor are appointed in writing where more than one contractor is involved, with a construction phase plan before work starts; design and wiring to BS 7671 (18th Edition, Amendment 4); commissioning and system documentation to IEC 62446-1; and a G99 connection, delivered under a JCT or NEC contract.
The capital figure is the denominator in the return, which is why getting it right and getting it fixed matters more than getting it low on paper. On a well-matched commercial system the payback period and the lifetime return both turn on the consumption profile, the tariff and the roof, and they improve where the year-one capital allowance applies. The cost and the return are not separate exercises.
Any payback or return figure is indicative, not financial or tax advice. Confirm the position with a qualified accountant or tax adviser. Your figure comes from a survey-led PV*SOL model, built from the same survey that produces the capital cost in the first place. The point is that the cost and the return are derived together, from your site, rather than read off a table. First-year capital allowances such as the Annual Investment Allowance can apply to qualifying plant, and an accountant can confirm what is available to your business.
Any payback and return shown for your project are illustrated from your own site survey, half-hourly consumption data and the agreed installed cost, not from a representative example. We confirm the inputs with you before they inform a decision.
A per-kWp headline collapses a dozen separate cost lines into one rate, which is exactly why it moves once the build starts. A survey-led price keeps those lines visible, and naming them is the easiest way to compare one quote against another on a like-for-like basis. A complete commercial figure carries the module and inverter supply, the mounting system matched to your roof covering, the DC and AC cabling and containment, isolation and protection, the metering and the AC interface to your distribution board. Around that hardware sit the works a brochure rate tends to drop: the structural appraisal, the access and scaffolding, the G99 application to Northern Powergrid managed through to a connection offer, commissioning and the documentation pack, and the contract and project-management overhead.
Two of those lines are statutory rather than optional. Because a system over 50 kWp almost always involves more than one contractor, the Construction (Design and Management) Regulations 2015, enforced by the HSE, require a principal designer and a principal contractor to be appointed in writing and a construction phase plan before work begins, which our CDM 2015 guide sets out in full. The design and wiring are built to BS 7671, and commissioning follows the verification regime in BS EN 62446-1. None of that is a margin a cheaper bidder has trimmed away; where it is missing from a quote, it is work that has been left for you to discover later. Our guide to how we quote shows the survey-led route a real number follows from first read to fixed figure.
The single biggest driver of the headline capital figure is the size of the array, but the cost does not rise in a straight line with kilowatt-peak. Larger systems spread the fixed costs of survey, scaffolding, design and the grid application across more capacity, so the cost per kWp usually falls as the array grows, up to the point where the roof, the structure or the connection imposes a step change. That is why the array is sized to your half-hourly load rather than simply filling the roof, a method our ROI and payback guide explains in detail, because oversizing buys capacity that exports cheaply rather than offsetting expensive import.
Two design choices commonly reshape the budget. Adding battery storage raises the capital cost but can lift self-consumption and open revenue from grid services, so it is modelled against your own numbers rather than bolted on by default. Separately, where the connection the network returns will not accept full export, an export-limitation scheme to ENA Engineering Recommendation G100, covered in our export limitation guide, lets a larger array connect by capping what it pushes to the grid. That can be the difference between a connection accepted as applied for and one that quotes reinforcement, which is the network-side variable our DNO guide sets out. Each of these is priced for your site rather than from a table.
The risk in a commercial solar budget is rarely the price you sign; it is the variations that arrive after you have signed. A quote built on a desktop estimate assumes a clean, strong, accessible roof and a straightforward connection, and when the structure needs strengthening, the scaffold is non-standard or the DNO returns conditions, those works appear as priced variations during the build. The bidder who left them out looked cheaper on the page and costs more by the time the system is energised. This is why writing a single scope of works that every installer prices against matters more than collecting three numbers built on three different sets of assumptions.
The defence against this is the order of operations: survey first, price second. We start with an in-house, fully insured drone survey that builds a measured 3D model of the roof, detailed in our drone survey page, so the design works from real geometry rather than an estimate, then confirm the structure, the access plan, the electrical route and the G99 position before a figure is set. The result is one fixed price that holds, rather than a low headline that drifts upward. For the works the array is checked against on a fragile or older covering, our quality without MCS guide explains how a commercial scheme over 50 kWp is assured outside the domestic certification scheme, by the engineering and contract stack rather than by a badge.
Our own insured pilot flies your roof and captures the real geometry and shading, so the design starts from your building instead of a satellite guess.
Booked to suit your operating hours
We model the array in bankable-grade software, size it around your daytime load, and set out generation, savings and payback across three funding routes.
Modelled, not promised
Designed and installed to BS 7671, commissioned to IEC 62446-1, connected under G99 and run under CDM 2015. Alectrona is typically the Principal Contractor.
Outside MCS, assured by the non-MCS stack
A 12-month defects period backed by an Insurance-Backed Guarantee, then ongoing operations and maintenance so the asset keeps earning for its full working life.
Kept performing, year on year
Indicative, not financial or tax advice. Confirm the position with a qualified accountant or tax adviser. Your figure comes from a survey-led PV*SOL model.
Last updated June 2026
Not an honest one. A per-kWp figure assumes a clean, strong, accessible roof and a straightforward grid connection, and it leaves out the works that vary most between sites: structure, scaffolding, the DNO connection and the electrical route. We would rather survey the roof and give you one fixed price that holds than quote a headline that moves once the real works appear.
Usually the site-specific works rather than the panels. Roof type and condition, whether the structure needs strengthening, the access and scaffolding required, the grid connection the network returns, and the electrical infrastructure to your distribution board all move the figure. A quote that looks cheaper up front can cost more overall if those items reappear as variations during the build.
It can. A system over 50 kWp is handled through an ENA Engineering Recommendation G99 application, and the network operator’s response shapes both cost and programme. A connection accepted as applied for is straightforward; one that comes back with conditions or reinforcement changes the picture. We confirm the connection position for your site as part of the survey, rather than assuming it.
We run an in-house drone survey to build a 3D model of your roof, then model generation against your half-hourly consumption in PV*SOL so the system is sized to your load. With the structure, access, electrical route and G99 position all confirmed, we produce a single fixed price set out so you can see what it covers, including the works a per-kWp rate omits.
It is the figure the return is measured against, so it matters most when it is accurate and fixed. The cost and the return are derived from the same survey: payback and ROI come out of the same survey-led PV*SOL model that produces the capital figure. Any payback or ROI figure is indicative, not financial or tax advice; confirm the position with a qualified accountant or tax adviser.
A different roof can move the figure even at the same array size, because the mounting and any remedial work change with the covering. A flat single-ply membrane, a standing-seam metal deck, a trapezoidal profile and a fragile older covering each need a different fixing method, and some call for remedial work before an array goes on. The drone survey and structural check confirm which applies to yours.
Possibly, but it depends on your tax position rather than the system. Commercial solar is plant and machinery, so qualifying spend can attract first-year allowances such as the Annual Investment Allowance, though group structures, accounting periods, asset-finance arrangements and the allowances in force when you invest all affect what is available. This is indicative, not tax advice. Confirm the position with a qualified accountant against your own circumstances.
The first feasibility read is quick once we have your half-hourly consumption data and can see the roof, because both feed the survey and PV*SOL model directly. A firm fixed price follows the in-house drone survey, the structural appraisal and the access plan, since those confirm the works a desktop estimate leaves out. The grid-connection position can extend the picture, because the G99 application to Northern Powergrid runs on the network operator's own timescale rather than ours, so we confirm where your connection sits before the figure is finalised.
A guide can only take you so far. The figure you get is modelled from your own half-hourly load and a system sized from the on-site drone survey. No obligation, and systems this size sit outside the domestic MCS scheme, so the assurance is the engineering stack.