Alectrona
Battery economicsA commercial battery does not earn from one thing. Its return is stacked from several jobs at once, net of the losses and degradation that are part of how the asset works.
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.
The return on a commercial battery is built from more than one revenue stream running together. No single job pays for the asset on its own. The case is made by stacking the value: shaving the demand peak that drives your capacity and demand charges, arbitraging the gap between cheap and expensive periods on a time-of-use tariff, storing more of your own solar so it offsets expensive import instead of being exported for far less, and earning from variable grid-services income where the site qualifies.
Against that you net off the costs that are real and physical: a round-trip efficiency loss every time you cycle the battery, and a slow capacity fade over its life. An honest return is the stacked value minus those losses, modelled against your actual half-hourly load. This page sets out the drivers so you can see how the return is built. The actual figure for your site comes from an on-site survey and a half-hourly PV*SOL model, not a rule of thumb. An interactive ROI calculator is coming; until it lands, your project figure comes from the survey and the model, sized to your building, not from a slider.
Brand-agnostic: the bankable battery that fits the project.
A commercial battery earns by doing several jobs in the same day. Each one is a separate driver, and they add up.
The mix that pays best depends entirely on your load shape and tariff. A site with a sharp afternoon peak leans on shaving; a site on a wide day-night tariff spread leans on arbitrage; a site with a large array leans on self-consumption. Most strong cases use all of them.
Two costs are physical and unavoidable, and any honest model carries them. The first is round-trip efficiency. Every cycle loses some energy to conversion and heat, so a unit stored is always worth slightly less than a unit you bought, and the arbitrage gain has to clear that loss before it counts.
The second is degradation. A battery's usable capacity fades gradually over its working life, so the value it can stack today is a little higher than the value it will stack later. We design around the maker's warranted capacity and cycle life rather than the nameplate, and we model the return across the full life of the asset, including the later years when capacity has faded. The makers we specify from publish these figures, and the warranted terms are part of why we work with them. Alectrona is brand-agnostic and specifies the bankable maker that fits the project.
We do not estimate the return from a rule of thumb. The method is the same one we use for the whole system: an in-house insured drone survey of the roof and site, then PV*SOL half-hourly modelling that runs your real consumption against the generation and the battery's dispatch. That is what tells you which drivers in the stack actually pay on your building, and how much, once the round-trip loss and degradation are netted off.
An interactive ROI calculator is coming and will let you explore the drivers for yourself. It does not exist yet, so we will not point you at a number it has not produced. Until it lands, the figure you rely on for your own project is the one the survey and the model give you, sized to your load and confirmed before contract.
Your return is the sum of the drivers above, minus the losses below them, modelled against your own building. On the value side sit peak and demand-charge reduction, time-of-use arbitrage, extra solar self-consumption and any variable grid-services income the site qualifies for. Against that you net the round-trip efficiency loss on every cycle and the gradual capacity degradation over the life of the asset. There is no single rule of thumb that fits every site, because the mix that pays depends on your load shape, your tariff and your roof. The figure you act on comes from the on-site survey and the half-hourly PV*SOL model, sized to your building and confirmed before contract.
One caveat sits on the battery itself. The capital-allowances treatment of standalone battery storage is not settled in public HMRC guidance, so we do not assert a specific allowance on the battery and you should not build a case on one. Model your own numbers from the survey, and confirm the tax position with your accountant or tax adviser before you commit.
The return moves with the size you install, and not in a straight line, which is why a single figure means little without the size attached to it. A battery sized to clip only your sharpest demand peaks is small, cheap to install and spends most of its capacity on the highest-value job, so the value it stacks per kWh is dense. Scale it up to ride longer arbitrage windows or to carry a backup load and the later kWh do lower-value work, so the average return per kWh softens even as the total saving rises. The honest question is never "what is the ROI" but "what is the ROI at this size, for this load, on this tariff".
That is why we model a curve, not a point. We run several candidate sizes against your half-hourly data and show how the stacked value and the payback shift as the battery grows, so the board can pick the point where the marginal kWh still earns its keep rather than the largest system a supplier can sell. The sizing logic that feeds this sits on the battery sizing page, and the single largest driver for most commercial sites, demand-charge reduction, is set out under peak shaving. The installed cost that anchors the payback half of the calculation is survey-led and explained on the battery costs page; we will not pretend a return without a real cost beneath it.
Where a site qualifies, the battery can earn from markets run or overseen by the National Energy System Operator (NESO) and regulated by Ofgem. The Capacity Market pays an availability income for being on call at times of system stress; the Balancing Mechanism and the frequency-response products, such as Dynamic Containment, pay for fast dispatch that helps NESO keep the grid in balance. Each is a real, named mechanism with its own rules, and an aggregator usually routes a small battery into them. None of it is a fixed cheque. The income depends on auction clearing prices, how often you are dispatched, the share an aggregator keeps and your asset's eligibility, so any number is modelled, not promised, and we never attribute a figure to NESO, Ofgem or any auction that those bodies have not published for your contract.
For that reason we build the ROI on the steadier jobs first, the demand-charge reduction, the arbitrage on your tariff and the extra solar self-consumption, and we treat grid-services income as a layer of upside on top. If it arrives it improves the case; if eligibility or prices move against you, the foundation still stands. How these markets work and who can enter them is set out under grid services and the Capacity Market, and the economics route through to commercial finance so the modelled return can be read against the way the asset is paid for.
A return is only as honest as the assumptions under it, so the model is built on figures you can verify rather than optimistic defaults. Degradation and cycle life come from the maker's warranted terms for the exact product, not the nameplate, and the cells are specified to recognised safety and performance standards such as IEC 62619 for industrial battery safety and IEC 62933 for the energy-storage system, with fire safety designed to BS EN and the principles in NFPA 855 and the guidance the HSE expects at this scale. Those standards do not set your return, but they set the warranted life the return is modelled across, which is why we name them rather than wave at "premium" hardware. The detail on this sits under fire safety.
The tariff assumptions, the import and export prices and the demand-charge bands come from your actual bills and your supplier, not a national average, and they are disclosed in the model so you can challenge them. The generation and dispatch profile comes from the same PV*SOL half-hourly run we use for the whole system, fed by an in-house insured drone survey, with the timeline and grid-connection position established early because a deferred connection delays the day the return starts. That sequencing is covered under design and engineering and the grid connection queue, and the way payback itself is constructed is unpacked in the commercial solar ROI and payback guide. Every figure you act on is confirmed before contract; this page explains the method, not a promised number.
The capital-allowances treatment of standalone battery storage is not settled in public HMRC guidance; confirm the position with your tax adviser.
It is stacked from several jobs running together: shaving your demand peak to cut capacity and demand charges, arbitraging the price gap on a time-of-use tariff, storing more of your own solar so it offsets expensive import instead of being exported cheaply, and earning a variable grid-services income where the site qualifies. No single one pays for the asset alone. The case is made by combining them, then netting off the round-trip loss and degradation. The size of the return for any given site comes from the survey and the model, not from a rule of thumb.
Yes. Two physical costs always apply. Round-trip efficiency means every cycle loses some energy to conversion, so a stored unit is worth slightly less than the one you bought. Degradation means usable capacity fades over the battery's life, so the value it stacks falls gradually over time. We model both against the maker's warranted figures and across the whole life of the asset, the later years included.
An interactive ROI calculator is coming and will let you explore the drivers for yourself. It does not exist yet, so we will not point you at a number it has not produced. In the meantime your figure comes from an in-house insured drone survey and PV*SOL half-hourly modelling run against your real load, which is more reliable than any slider because it is built from your actual building.
The capital-allowances treatment of standalone battery storage is not settled in public HMRC guidance, so we do not assert a specific allowance on the battery and we would not build your case on one. Any return figure we model is sized to your building, not a promise. This is not financial or tax advice; confirm the position with your accountant or tax adviser before you rely on it.
That depends on your load shape and tariff. A sharp afternoon peak leans on peak shaving; a wide day-night price spread leans on arbitrage; a large array leans on self-consumption. Most strong cases use all of them. The PV*SOL model tells you which drivers actually pay on your building and by how much, once losses and degradation are netted off, sized to your load and confirmed before contract.
The return starts at energisation, which on a survey-led commercial project is typically several weeks to a few months after contract, driven mainly by the grid-connection position rather than the install itself. A G99 connection or a queued capacity offer from your network operator can extend the timeline, so we establish that early and model the payback from the realistic energisation date, not the order date. We confirm the programme before contract; see the grid connection queue.
We will not print a price on this page, because the honest figure comes from the survey rather than a rule of thumb. The installed cost anchors the payback half of every ROI we model, so it has to be real before any return means anything; we size the battery and inverter to your half-hourly load, then cost the exact configuration, and we will not pretend a return without a real cost beneath it. What drives that number is set out on our battery costs page, and the figure you act on is confirmed before contract.
We model your half-hourly load and your solar against a battery sized from an on-site survey, so the figure you get is yours, not a from-price. Capex first, with the bankable brand that fits the project.