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.
Alectrona
Commercial guideESOS and SECR: how solar lowers the energy and carbon you report
If your business is large enough to fall under ESOS or SECR, on-site solar is a recognised energy-efficiency measure that lowers the energy use and the Scope 2 emissions you have to disclose.
- Commercial scale, over 50 kWp
- On-site 3D drone survey + PV*SOL
- Engineer-led, outside MCS
The feedback we work to earn
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.
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.
- ESOS Mandatory phased energy audit for large undertakings
- SECR Energy and carbon disclosure in the directors' report
- Qualification Set by employee, turnover and balance-sheet tests; confirm with your advisers
- Solar's effect Lowers reported energy use and Scope 2 emissions
- Carbon basis Displaced grid kWh x published government carbon factor
ESOS and SECR
OrientationThis is a plain-English orientation to ESOS and SECR for a commercial buyer, not formal compliance or accounting advice; we confirm the energy and carbon inputs for your project, and your advisers confirm your reporting obligations.
For a large UK business, energy is not only a cost line. It is a reporting obligation. Two schemes sit behind that: the Energy Savings Opportunity Scheme (ESOS), which makes qualifying organisations audit their energy use and identify ways to cut it, and Streamlined Energy and Carbon Reporting (SECR), which makes qualifying companies disclose their energy consumption and carbon emissions in their annual accounts.
Commercial solar is relevant to both. It is an energy-efficiency measure an ESOS audit can identify, and it directly lowers the energy consumption and Scope 2 emissions that SECR asks you to report. What follows is a plain-English orientation to how the two schemes work and where a roof-mounted array fits, so the regulatory upside of a project is something you can weigh alongside the bill saving.
What ESOS and SECR each require
The two schemes do related but different jobs, and it helps to keep them apart.
- ESOS is an energy-audit scheme. Qualifying organisations must, on a recurring phased cycle, assess their total energy consumption across buildings, processes and transport, and identify cost-effective opportunities to reduce it. The output is a set of recommended energy-saving measures, signed off and notified to the regulator.
- SECR is a disclosure scheme. Qualifying companies must report their energy use, their greenhouse-gas emissions and at least one intensity ratio within their annual directors' report, alongside a narrative on the energy-efficiency action taken in the year.
ESOS asks you to find the savings; SECR asks you to publish the numbers. Solar is relevant to both, because it is a measure ESOS can identify and a change SECR will show in the reported figures the following year.
An energy-audit scheme
Qualifying organisations must, on a recurring phased cycle, assess their energy use and identify cost-effective ways to cut it.
- Assesses total energy consumption across buildings, processes and transport
- Identifies cost-effective opportunities to reduce it
- Output is a set of recommended energy-saving measures
- Signed off and notified to the regulator
A disclosure scheme
Qualifying companies must publish their energy and carbon figures in the annual directors' report each financial year.
- Reports energy use, greenhouse-gas emissions and at least one intensity ratio
- Sits within the annual directors' report
- Adds a narrative on the energy-efficiency action taken in the year
- Read by auditors, lenders and shareholders
Who has to comply
Both schemes are aimed at large undertakings, and qualification turns on tests such as employee numbers, annual turnover and balance-sheet totals, with quoted companies brought in under SECR as well. Those thresholds are set in the regulations and are revised over time, so the precise tests, and whether a particular group structure or subsidiary is caught, are best confirmed against the current rules rather than a fixed figure quoted here.
The practical point for a finance or facilities director is that if your organisation is large enough to be weighing a commercial solar array above the domestic MCS scale, there is a good chance one or both schemes already apply, or will as you grow. We do not determine your qualification, and nor should you rely on this page for it. Your compliance or accounting advisers confirm the status; what we can do is make sure a solar project is specified so the energy and carbon effect is clear and usable in your reporting.
How solar moves the numbers you report
On-site solar changes the figures in both schemes in a direct, measurable way. Every unit the array generates and you consume on site is a unit you do not import from the grid.
- Reported energy consumption falls. SECR reports total energy use, and self-consumed solar reduces the grid electricity that sits in that total. The reduction shows in the year the system is generating.
- Scope 2 emissions fall. Scope 2 under the GHG Protocol covers the emissions from electricity you buy. Generating your own and importing less cuts that figure. The saving is calculated as the displaced grid kWh multiplied by the relevant grid carbon factor, using the published UK government conversion factors, rather than as an invented headline tonnage.
- The ESOS audit has a measure to point to. An array sized to your daytime load is exactly the kind of cost-effective, identified opportunity an ESOS assessment is meant to capture.
The honest framing is that solar lowers the energy and carbon you report and meets the schemes' intent of using energy more efficiently. The size of each effect depends on how much of the array's output your site consumes, which is why we model self-consumption against your real load before specifying anything.
Where we fit, and where your advisers do
Our role is the engineering. We assess the roof with our in-house drone survey, size a system to recognised component and installation standards for arrays above the domestic MCS scale, and model the generation and the self-consumption you can expect. From that we can give you the displaced grid kWh that feed an ESOS measure or an SECR disclosure.
The reporting itself stays with your own people. The ESOS lead assessor signs off the audit, and your accountants and compliance advisers prepare the SECR disclosure in the directors' report. We provide the system specification, the expected generation and the carbon methodology they need; we do not file your return or certify your compliance. That division keeps each part with the party accountable for it.
How does the ESOS four-year compliance cycle actually run?
ESOS is a phased scheme rather than a single audit, and the phase you are in sets the deadline you work back from. The Energy Savings Opportunity Scheme runs in compliance phases, each opening on a fixed qualification date and closing on a compliance date by which a qualifying organisation must have completed its energy assessment and notified the Environment Agency, which administers the scheme in England and acts as the lead UK regulator alongside the devolved equivalents in Scotland, Wales and Northern Ireland. The cycle repeats, so an organisation caught in one phase plans for the next rather than treating compliance as closed.
The assessment itself has a defined shape set out in the ESOS Regulations and the Environment Agency's published guidance on gov.uk. It must cover the organisation's total energy consumption across buildings, industrial processes and transport, identify the areas of significant energy use, and surface cost-effective energy-saving opportunities. The work is signed off by an approved ESOS lead assessor and a board-level director, and recent changes to the scheme have added an action-plan element, so the obligation now leans towards acting on what the audit finds rather than filing it. Phase dates, qualification dates and the detail of the action-plan duty are set in the regulations and revised between phases, so treat this as orientation and confirm the current phase and its deadlines against the live Environment Agency guidance rather than any date fixed on this page. Where the array itself drives the energy picture the audit characterises, the modelling sits in our feasibility study guide.
What does SECR actually require a company to report, and where does it appear?
SECR is a Companies Act 2006 disclosure that lives in the directors' report rather than a standalone return to a regulator. Streamlined Energy and Carbon Reporting was introduced through regulations amending the Companies Act 2006, and for a quoted company, a large unquoted company or a large limited liability partnership in scope it requires specified energy and carbon information to be disclosed within the annual report each financial year. Because it sits in statutory accounts, the figures are read by auditors, lenders and shareholders, which is what makes the underlying method matter as much as the headline.
The disclosure has a defined content set under the regulations and the government's published SECR guidance on gov.uk. In broad terms a large unquoted company reports its UK energy consumption in kWh, the associated greenhouse-gas emissions, at least one intensity ratio, a narrative on the energy-efficiency action taken in the year, and the methodology used; a quoted company reports global emissions on a wider basis. The emissions are quantified using the Greenhouse Gas (GHG) Protocol and the UK government conversion factors, which is the same framework an honest solar carbon figure is built on, set out in our carbon savings methodology guide. The exact scope, the de minimis exemptions and which company size tests apply are set in the regulations and have been amended since introduction, so confirm the current content requirements with your accountants rather than relying on a list here. Our part is the metered generation behind the energy and Scope 2 lines, drawn from the half-hourly metering data your site already produces.
How does on-site solar move the SECR intensity ratio, as well as the total?
The intensity ratio is where a solar project often reads most clearly in a SECR disclosure, because it normalises the saving against a measure of business activity. SECR requires at least one intensity ratio: emissions or energy expressed per unit of an activity metric the company chooses, such as per square metre of floor area, per unit of output or per full-time employee. A ratio strips out the noise of a growing or shrinking business and shows whether the organisation is genuinely using energy more efficiently, which is precisely the question the scheme is built to surface.
On-site self-consumption acts on both halves of that fraction in your favour. Every kWh the array generates and you use behind the meter lowers the grid electricity in the numerator, so the emissions figure falls while the activity denominator holds steady, and the ratio improves. The GHG Protocol Scope 2 guidance governs how the emissions side is quantified, and the location-based and market-based distinction it draws affects how the self-consumed and exported shares are treated, so the ratio has to be stated on a consistent basis year on year. The honest framing is that solar improves a reported intensity ratio measurably, but the size of the move depends on how much of the output your site actually consumes, which is why we model self-consumption against your real load before any figure is offered. Where export complicates the boundary, we keep the carbon side and the financial side apart and route the latter to our finance guidance.
Can an ESOS audit name solar as a recommended measure, and what does that lead to?
An ESOS audit is designed to surface cost-effective opportunities, and an array sized to your daytime load is exactly the kind of measure it is meant to recommend. The scheme's purpose, as the Environment Agency sets out on gov.uk, is to identify where an organisation can use energy more efficiently and to put those opportunities in front of a board that can act on them. On-site generation sized against the demand the building actually carries through the day fits that test directly, so a lead assessor can list it among the recommended measures rather than it sitting outside the audit's scope.
Being named in the audit gives a project a documented, assessor-reviewed place in the organisation's own energy strategy that a bare bill saving does not carry. With the action-plan element now part of the scheme, a recommendation also feeds the forward plan the board signs, which is useful when a capital request needs internal justification. The recommendation is the lead assessor's call, made against the evidence; our part is to supply the system specification, the modelled generation and the self-consumption analysis that let the measure be assessed properly. The same evidence base overlaps with a commercial EPC recommendation report, which we cover alongside the building-rating duty in our MEES, EPC and commercial solar guide. None of this is a substitute for your lead assessor's judgement; treat it as orientation on how a solar measure can be carried through the audit rather than a promise that it will be.
How do the ESOS audit and the SECR reporting timelines line up with a solar install?
The two schemes run on different clocks, and a solar project lands in each at a different point, so the timing is worth planning rather than leaving to chance. ESOS works to a fixed compliance date at the end of each multi-year phase, with the assessment and notification due by that date. SECR works to your own financial year, with the disclosure appearing in the directors' report for the year in which the energy was used. A system commissioned partway through a year therefore shows a part-year saving in that year's SECR figures and a full year in the next, while its place in an ESOS audit depends on where commissioning falls relative to the phase deadline.
The practical sequence is that the metered generation data is the connecting thread. From commissioning, the array produces the half-hourly generation and self-consumption record that feeds both a SECR energy and Scope 2 line and, if the timing aligns, an ESOS measure or its evidence base. Because SECR is read year on year, a consistent, dated methodology matters more than a single impressive first-year number, which is the same discipline our carbon savings methodology guide applies. Confirm your own ESOS phase deadline and your financial-year end with your advisers, since those two dates, set respectively by the regulations and by your accounts, determine when a given install first appears in each report. The wider commercial cost picture stays survey-led and specific to your roof and load, set out in our commercial solar cost guide rather than quoted here.
Past the guide, this is how your figure actually gets set.
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Survey On-site 3D drone survey
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
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Model PV*SOL design and proposal
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
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Install Engineered and installed
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
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Aftercare Operations and maintenance
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
Last updated June 2026
ESOS and SECR: common questions
ESOS, the Energy Savings Opportunity Scheme, is an auditing scheme: qualifying organisations assess their total energy use on a phased cycle and identify cost-effective ways to cut it. SECR, Streamlined Energy and Carbon Reporting, is a disclosure scheme: qualifying companies report their energy consumption and greenhouse-gas emissions in their annual directors' report. ESOS finds the savings; SECR publishes the numbers.
It depends on tests such as employee numbers, turnover and balance-sheet totals, with quoted companies also brought into SECR. Those thresholds are set in the regulations and change over time, so we do not state fixed figures here. If you are large enough to be considering a commercial array, one or both schemes may well apply. Your compliance or accounting advisers confirm your status; this page is orientation, not a qualification determination.
Scope 2 under the GHG Protocol covers the emissions from the electricity you buy. When you generate your own power on site and import less, that figure falls. The saving is calculated as the grid electricity you displace, in kWh, multiplied by the relevant published UK government carbon conversion factor. It is a methodology applied to your real generation, not an invented absolute tonnage.
Yes. ESOS audits are meant to identify cost-effective ways to reduce energy use, and on-site generation sized to your daytime load is exactly that kind of measure. An array can be one of the opportunities an assessment surfaces and recommends. The audit itself is signed off by your ESOS lead assessor; we supply the system specification and expected generation that inform it.
No. We design and build the solar array and model the generation and self-consumption, then give you the displaced grid kWh and the carbon methodology behind them. The ESOS audit is signed off by a lead assessor, and the SECR disclosure is prepared by your accountants and compliance advisers in the directors' report. We provide the engineering inputs; the reporting stays with the parties accountable for it.
No. The metered generation and self-consumption data that feed an ESOS measure or a SECR energy and Scope 2 line fall out of the half-hourly metering and modelling we already do, so there is no separate compliance-data line. The system cost itself is survey-led and specific to your roof and load rather than a per-kWp rate, which is why we set it out in our commercial solar cost guide rather than quote a figure here.
It depends on the two clocks. For SECR, the saving appears in the directors' report for the financial year the array is generating in, part-year if commissioned partway through, full-year after. For ESOS, it depends on where commissioning falls against your phase compliance deadline. The metered generation record starts at commissioning and feeds both, but confirm your financial-year end and current ESOS phase date with your advisers.
Get the numbers for your roof.
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.
- On-site 3D drone survey, fully insured in-house pilot
- Half-hourly load modelled in PV*SOL before anything is specified
- Engineer-led, assured to the non-MCS standard (CDM 2015)
- Capex, lease-purchase or PPA, whichever suits you