Solar Inverter and Microinverter Manufacturers in the UK

Every home solar system needs an inverter: the device that converts the direct current made by the panels into the alternating current a home and the grid use. Solar panels are the most common domestic renewable energy source in the UK¹, with around 1.65 million homes generating their own solar energy as of June 2026², so inverters from a handful of makers are now fitted on well over a million roofs. The makers a UK household is likely to meet include SolaX, Fronius, Sungrow, Solplanet, SolarEdge and Sunsynk, alongside microinverter specialists.

There are three broad designs. A string inverter takes the output of several panels wired in series and is the most common and cheapest option³. A microinverter sits behind each panel and converts its power individually. A hybrid inverter combines inverter technology with battery storage. Most makers now sell more than one of these, and several also sell batteries, EV chargers and a monitoring app that ties them together.

The inverter is also the part of a solar system that wears out first. The Energy Saving Trust puts replacement at every 10 to 15 years, usually at a cost of around £800⁴, and most inverters carry warranties of five years as a minimum, which can often be extended by up to 15 years⁵. The maker behind the inverter therefore matters for longer than the purchase: its warranty process, spare parts and app support shape what ownership looks like.

String inverter or microinverter: which suits which roof

The choice between one central inverter and a microinverter behind each panel depends mainly on the shape of the roof and how much shade falls on it. SolaX, which sells both, lists the conditions under which its guidance points to a string inverter⁶:

• the roof is simple and unshaded
• the panels face in similar directions
• lower upfront cost is important
• maintenance at ground level is preferred
• a DC-coupled battery is planned

Microinverters, by the same maker's account, are best suited to residential, shaded and small-scale solar⁷. The reason lies in how a string behaves. Sungrow explains that a string inverter operates at the string level, so if one panel has performance problems, it can affect the output of the entire string⁸. A chimney shadow or a panel facing a different way drags down its neighbours. With a microinverter, each panel works on its own.

Servicing is the other side of the trade. SolaX notes that string inverters are easier to service at ground level, while repairing a microinverter may require roof access and panel removal⁶. A fault on a string inverter in a loft or garage is a simpler job than a fault on a unit bolted under a panel two storeys up.

Between the two sit optimisers and short-string designs. SolarEdge states that its Home Short String Inverter is optimised for complex roofs, including multi-facet roofs and different orientations, and that it can be installed indoors or outdoors⁹. Sungrow's residential package pairs a string inverter with an optimiser and its monitoring platform (covered below).

Microinverters have also reached a new market: plug-in solar. Which? describes one kit, the InstaGen plug-in solar kit, as two 435W bifacial panels with an 800VA microinverter and a mounting frame for gardens, balconies and walls¹⁰. These kits are self-installed, which is a different route from a roof system fitted by an installer.

For the head-to-head between the two best-known exponents of each approach, see SolarEdge vs Enphase, and for the microinverter makers themselves, Enphase microinverters and APsystems microinverters.

The manufacturers a UK household is most likely to meet

The UK solar base is large and still growing, which is why so many inverter brands compete for it. Estimates of its size differ by source and date: the Energy Saving Trust cites over 1.3 million homes generating electricity from solar panels¹¹, Uswitch refers to about a million households with solar panels¹², and Which? reported around 1.65 million homes in June 2026². The figures come from different dates and counting methods, and the newest is the highest.

Hybrid inverters are the fastest-moving part of the range, because they let one box manage both panels and a battery. Marley describes hybrid inverters as combining inverter technology with battery storage¹³. String inverters remain the workhorse for solar-only systems: Sunsynk, for example, sells a String Inverter 10kW 3P intended for solar-only installations¹⁴, and Canadian Solar lists residential string inverters alongside its panels¹⁵.

The brands covered in this section and on dedicated pages include:

Other brands with their own pages include GoodWe, Growatt, Solis, SMA, Huawei, Fox ESS and GivEnergy. The list describes what is sold, not a ranking. Who owns which brand is set out in who owns which energy brand, and where the equipment is made in where home energy products are made.

SolaX: string, hybrid and microinverter options from one maker

SolaX is one of the few makers covering all three inverter types for UK homes. The company describes its range as hybrid inverters, string inverter and micro inverter options, home battery storage, solar EV charger integration and all-in-one energy storage systems, with app-based monitoring through SolaXCloud¹⁶. It groups batteries, storage inverters, string inverters, microinverters, the Smart EV Charger G2, heat pump products and SolaXCloud under one platform architecture¹⁷.

The practical point of that breadth is expansion. A household that starts with panels alone can, on the maker's account, add a battery or EV charger later within the same brand and app. SolaX states that its residential string inverters integrate with EV chargers, heat pumps and energy storage, and that they allow up to 200% DC/AC oversizing, meaning more PV modules can be connected than the inverter's output rating alone would suggest¹⁸.

SolaX's own guidance matches its products to use cases as follows¹⁹:

Which? notes that SolaX battery systems are available via UK installers²⁰, which is the usual route for the brand's roof systems.

The single-brand approach cuts both ways for independence. One app and one support line are simpler to live with, and parts are designed to work together. But the whole system then depends on one company's cloud service, firmware updates and continued presence in the UK. How that support ages is covered in firmware updates and product support life, and what happens when registration goes wrong in SolaX warranty registration problems.

Fronius Symo: three-phase and transformerless, for indoor or outdoor walls

Fronius Symo inverters are string inverters built for a three-phase supply. The maker describes the Symo as "the transformerless Fronius Symo is the three-phase inverter", and its datasheets for each model covered here list the same core design²¹. Most UK homes have a single-phase supply, so the Symo applies chiefly to larger homes, farms and properties that already have three phases.

Every Symo model in the datasheets shares three features: a transformerless design, regulated air cooling, and approval for installation indoors and outdoors. The models also share one case size, 432,5 mm wide by 642,5 mm high by 205,5 mm deep²². The Symo 3.0-3-M is listed with protection class 1²¹.

The table draws on Fronius's own datasheets for each model²¹.

Because the Symo is a pure string inverter, it does not manage a battery on its own. A household adding storage to a Symo system would need a separate battery system, and the choice between AC and DC coupling becomes an installer's design question. Fronius's rules on returning faulty parts are covered in Fronius faulty part returns.

Sungrow: string inverters, optimisers and iSolarCloud monitoring

Sungrow makes inverters across the scale from a single panel to a power station. Its product range includes micro-inverters, residential inverters, string inverters, central inverters and modular inverters, the last described by the maker as merging the advantages of central and string designs²⁴. For homes, Sungrow sets out a residential PV solution built from three parts: a string inverter, an optimiser and its iSolarCloud monitoring platform²⁵.

The optimiser answers the string inverter's main weakness. Sungrow itself explains that string inverters provide monitoring at the string level and that one underperforming panel can affect the whole string⁸. Adding optimisers on the panels is the maker's route to panel-level control while keeping a single inverter on the wall.

Monitoring runs through iSolarCloud. Sungrow states that its hybrid inverter comes with intelligent monitoring and control systems and tracks system performance in real time²⁶. In its general guidance on string inverters, the company notes that advanced inverters feature remote monitoring and diagnostics, with monitoring at the string level²⁷. These are the maker's general descriptions rather than tested results for a specific model.

Remote diagnostics have a practical value: an installer or the maker can often see a fault before visiting. They also create a dependence. The monitoring and some control functions rely on the maker's cloud platform, an internet connection and continued app support. Sungrow's batteries and hybrid range are covered in Sungrow home batteries and solar inverters.

Solplanet warranty: 5 years as standard, up to 10 extended, and how claims work

Solplanet makes single and three-phase hybrid inverters for residential, commercial and industrial settings²⁸. Its UK warranty terms are unusually explicit about how a claim works, which makes them a useful example of what to look for in any maker's cover.

Length of cover

Solplanet offers end users a standard warranty of up to 5 years, which can be extended for up to 10 years²⁹. The two figures appear on the same warranty pages and describe the standard term and the extended option; they are not in conflict, but the extended cover is not automatic. The maker states the warranty sits alongside the legal rights a buyer already has:

When the clock starts

Making a claim

1. Check the warranty status of the inverter, connection or monitoring device with Solplanet's online validation tool²⁹.
2. Contact the customer support department, or go directly to the Online Claim Form³⁰.
3. A Service Specialist provides support on the fault³⁰.
4. If necessary, Solplanet's logistics network delivers a replacement inverter directly to the owner³⁰.

How this compares

Solplanet's standard term sits at the minimum the Energy Saving Trust describes for most inverters, five years, with extension possible up to 15 years at some makers⁵. Plug-in kits are showing longer headline terms: Which? reports a 12-year warranty on the InstaGen kit's inverter¹⁰. Solar panels, by contrast, commonly carry warranties of 25 years or more, so the inverter is almost always the first component to fall out of cover. General guidance on terms and registration is in manufacturer warranties and registering a warranty and keeping it valid.

Costs and availability: replacement around £800

Inverters are rarely priced to householders on their own when a system is new: the price of a roof system is quoted by the installer as a whole, and the inverter is one line within it. Published figures for a replacement inverter are clearer.

The independent figures agree on the middle of the range: around £800, within a band of about £500 to £1,000. The difference comes down to system size and brand. VAT treatment is not stated in these figures. The two maker figures come from companies selling portable power and batteries, so they are a guide to the market rather than an independent benchmark. The same battery maker notes that prices for the same capacity can vary by 20 to 30 percent between installers³³.

The Centre for Sustainable Energy expects an inverter may need replacing after around 10 years³¹, and the Energy Saving Trust gives every 10 to 15 years⁴. Over a panel lifetime of 25 years or more, a household should therefore expect to buy at least one replacement inverter. That replacement need not be the same brand, but the choice may be limited by the battery, app or optimisers already fitted.

Most roof-mounted inverters are sold through installers and wholesalers rather than direct to householders; the trade-offs are explained in buying direct from a manufacturer or through an installer. Plug-in solar is the exception: plug-in panels are now available to buy and self-install in the UK³⁵, with microinverters included in the kit.

What owning the inverter means for your energy independence

The inverter is the gate between a household's own generation and its own use. Without it, panels produce nothing a home can run on. That makes it the component that most determines how independent a solar home really is.

What it gives

A working inverter lets a home use its own electricity first and export the rest. With a battery on a hybrid inverter, Uswitch reports a self-consumption rate of 70% with a 10kWh battery³⁶. Across the country, UK homes had 6.6GW of solar capacity installed as of May 2026³⁷, and Solar Energy UK links solar growth to reducing dependence on fossil fuel imports³⁸.

What dependence remains

• The grid. A standard grid-tied inverter shuts down during a power cut for safety, so panels alone do not keep the lights on. Backup needs a hybrid inverter and battery designed for it.
• The maker. Warranty claims, replacement units and spare parts depend on the manufacturer staying in business and in the UK market; see when an energy equipment manufacturer fails.
• The cloud. SolaXCloud, iSolarCloud and similar platforms depend on the maker's servers and a home internet connection. Firmware updates arrive through them, and support periods differ by brand.
• The replacement cycle. An inverter replaced every 10 to 15 years⁴ means a recurring cost and a recurring chance to choose a different maker.

Reducing single points of failure

The evidence points to a few things that make ownership less fragile: a registered warranty with the installation date recorded, knowing the start rule for the warranty (as in Solplanet's six-month shipment rule), and understanding which functions work locally and which need the app. Microinverters spread the risk: one failed unit costs one panel's output rather than the whole array's, though the repair itself may need roof access⁶.

The wider picture across batteries, heat pumps and chargers is set out in manufacturers and household energy independence, and the full list of equipment makers in the manufacturers guide.