Alectrona
Commercial inverters · over 50 kWpCommercial solar inverters are the working heart of a system over 50 kWp. We specify the one that fits the design, the roof and your DNO export position, from a line-up we can actually procure and support through UK distribution.
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 inverter is the part of a commercial solar system that does the work every second of daylight. It converts the DC your modules generate into the AC your building and the grid use, holds the array at its most productive operating point across changing light, and manages how and when power is exported. On a larger roof it also governs how the system behaves under shade, how it shuts down safely for fire crews, and what you can see when something is not performing. Get the inverter wrong and a good array underperforms quietly for years. Get it right and the system earns what the model said it would.
For a system over 50 kWp there is rarely a single correct answer, and the right choice is a set of engineering trade-offs rather than a brand preference. A string inverter is efficient and cost-effective on a clean, uniform roof. A DC-optimised architecture, with electronics at each module, earns its place on a roof broken up by plant, rooflights, dormers or shading, where it recovers yield the string layout would lose and gives you per-module monitoring and rapid shutdown. The phase configuration has to match your supply, the MPPT count has to suit how the roof is split into orientations, and the inverter rating has to be designed around the export limit your Distribution Network Operator will actually grant, which is frequently lower than the array could push.
So we do not start from a datasheet or a price list. We start with an on-site survey and a PV*SOL model of your specific roof, shading and consumption, and we design the inverter into that. The output is a system sized to your site and your connection agreement, with the inverter selected to suit it. There is no published "from" figure on this page, because a meaningful number for a commercial system comes from the model, not from a brochure.
Our commercial inverter line-up is eight brands we can reliably procure and support through UK distribution: Fox ESS, SolaX, Solis, SolarEdge, Sigenergy, SMA, Sungrow and Fronius. We do not lead with a single badge. A specification is only as good as the parts you can actually get on a real lead time, with spares, firmware support and a warranty route that exists in the UK rather than in theory, so the line-up is built around procurability and support as much as engineering, and the brand is then chosen to fit the design. That is the same discipline we apply to our commercial battery storage line-up, and it sits inside our wider commercial solar engineering approach.
We are precise about what each brand is, and we do not borrow trust signals that do not apply. "BloombergNEF Tier 1" is a financeability scheme for PV modules and has nothing to do with inverters, so we never attach it to a brand here. There is a separate BloombergNEF Inverter Bankability Survey, and it is led by Sungrow, which is in our line-up and has held the top position six times. That is the one citable inverter-bankability position any of our brands carries, and we attach it to Sungrow precisely, not to the line-up as a whole. For every other brand, honest inverter standing means an established manufacturer, a named warranty, a working UK distribution and support channel, and the terms confirmed in writing for your specific project.
On that honest basis: Sungrow is the world's largest inverter maker by shipments and leads the BloombergNEF Inverter Bankability Survey, with a continuous three-phase range to 150 kW and a 350 kW machine for large ground-mount. SMA brings 40-plus years of German engineering and the deepest plant-control and export-limitation stack of our brands, which earns its place on large connections where the DNO sets firm conditions; we state its restructuring plainly on its own page. Fronius is the EU-made, family-owned, financially independent choice, with a genuinely strong service and warranty scheme. Solis (Ginlong) is one of the larger global string-inverter makers by shipment volume with a broad three-phase range, a statement about scale rather than bankability. Fox ESS and SolaX give us well-supported value and mid-market three-phase string inverters with established UK distribution, sensible choices for straightforward rooftop arrays. SolarEdge is technically distinctive: its DC-optimised, module-level architecture gives per-module monitoring and rapid shutdown, genuinely valuable on shaded or complex roofs and for safety. It carries one caveat we state plainly: a GAAP net loss of around US$1.81bn for 2024, including write-downs of over US$1bn, and further loss into 2025, so its financial standing warrants current due diligence. Sigenergy is a fast-growing newer entrant, founded around 2022 by a senior team formerly at Huawei, with strong product and a shorter track record we treat honestly by confirming warranty and support per project.
None of this is a ranking. The inverter is chosen to fit the design, the roof and the export agreement, and we will tell you which one we are proposing and why, with the warranty confirmed before contract.
China
Established global inverter maker: third by shipment volume in 2024 and fifth in Wood Mackenzie's first-half 2025 scored manufacturer ranking, with UK distribution and a standard manufacturer warranty. Bankability standing is confirmed per project, not assumed.
China
A new but well-funded manufacturer with active UK distribution, in-stock M1 commercial PV inverters and a stated 10-year product warranty; no independent bankability ranking, so suitability is confirmed per project rather than asserted.
China
Established value/mid-market brand with strong UK distribution and stock, named registerable warranties, and good parts availability; not an independent inverter-bankability-survey leader, so no Tier 1 claim. We confirm warranty terms and support per project.
United States
Established manufacturer with a named 12-year inverter warranty (extendable to 20) and UK distribution; we verify warranty backing and current financial standing per project rather than presenting it as a top-tier bankable inverter.
China
Established mid-market three-phase maker with a named 10-year UK warranty (extendable) and live UK distribution; we make no Tier 1 or bankability claim and confirm warranty terms and support per project.
Germany
Long-established German manufacturer (founded 1981) with one of the deepest monitoring and plant-control stacks in the industry and a 5-year standard string-inverter warranty extendable to 10, 15 or 20 years; in restructuring across 2024 to 2025, with the commercial and utility division the healthier part. FY2025 net loss about EUR 181m, EBITDA before one-time items positive at about EUR 107m but negative once one-time items are counted. SMA does not lead the BNEF Inverter Bankability survey (Sungrow does), so no most-bankable claim; we verify the standard warranty term, warranty backing and current standing per project.
China
The strongest standing in our inverter line-up: the world's largest inverter maker by shipments (around 143 GW in 2025, roughly 30% global share) and ranked No.1 in BloombergNEF's 2025 Inverter Bankability Survey with 100% recognition, the sixth time at the top. That is the inverter-supplier survey, distinct from the module Tier 1 list. We confirm the exact warranty term and the supplier standing per project rather than assuming them.
Austria
Established, financially independent family-owned manufacturer with EU manufacturing, a dedicated UK operation and a size-based warranty scheme (free Solar.web extension to a total of 10 years for units under 50 kW and 5 years for units of 50 kW and over such as the Tauro ECO, with a paid extension to a total of 15 years). Not the BNEF inverter-bankability leader, so no Tier 1 claim; warranty term, category and support confirmed per project.
Huawei's SUN2000 is a technically strong inverter and Huawei is a global shipment leader, so this is not a comment on the engineering. We do not lead with it for UK commercial work because of the well-documented security and procurement sensitivity around Huawei equipment in infrastructure, alongside considerations about support longevity through the asset's life. If a client specifically requires Huawei and is comfortable with that position, we can discuss it. For most commercial projects we specify from our UK-procurable line-up of Fox ESS, SolaX, Solis, SolarEdge, Sigenergy, SMA, Sungrow and Fronius, which we procure and support directly through UK distribution.
Yes, and all three are part of our commercial line-up with a page of their own. SMA brings the deepest plant-control and export-limitation stack of our brands for large connections; Sungrow is the world's largest inverter maker and the BloombergNEF Inverter Bankability leader; Fronius is the EU-made, family-owned, financially independent choice. Alongside them we specify Fox ESS, SolaX, Solis, SolarEdge and Sigenergy, all procurable and supported through UK distribution. The inverter is chosen to fit the design, the roof and your DNO export position, not picked for the badge on the case, and we confirm warranty and UK support before contract.
It comes out of the design, not off a price list. We survey the roof, model your specific shading, orientation and consumption in PV*SOL, and design the array around the export limit your Distribution Network Operator will grant, which is often lower than the roof could physically support. The inverter rating, phase configuration and MPPT count are then selected to match that design and that connection agreement. Because the number is derived from your model rather than a brochure, you will not see a published 'from' price here; you get a figure built for your site after the survey.
It depends on the inverter and the connection, and we confirm both before contract. Established brands held in UK distribution stock can be on a short lead time, while a larger central inverter or a constrained connection extends it. The G99 connection process with your Distribution Network Operator is usually the longest single item, so we start it early and design the array around the export position they confirm. We give you a dated programme after the survey and the model, not a generic promise.
Every system we specify reports to the manufacturer's monitoring platform, and on a DC-optimised SolarEdge design that visibility goes down to each individual module, so a single underperforming string or panel is visible rather than hidden in the total. We use that data for ongoing operations and maintenance: spotting drift early, planning service before it becomes a fault, and confirming the array is earning what the model projected. Inverter warranties and support are handled through the UK distribution channel for the brand we specify, and we confirm the warranty term and the support route in writing before contract rather than leaving it to assumption.
The inverter is one line in a survey-led system cost, and on a typical commercial array it is a smaller share of the total than the modules, mounting and electrical work. We do not publish a per-kWp or a 'from' figure for it, because a meaningful number comes from the on-site survey and the PV*SOL model against your half-hourly load, not from a price list. You see it costed inside the whole system, and our commercial solar cost guide covers what drives that figure, while finance covers how it can be funded.
We size the array in PV*SOL, set the export position with your DNO, and specify the inverter that fits, with the model and warranty named and no from-price.