The inverter is the heart of every solar system – and in 2026 the choice falls primarily between the established names Fronius, SMA, Huawei and SolarEdge, plus providers such as Kostal or Sungrow. More important than the make is the appropriate design (string, power optimiser or microinverter) and a manufacturer whose service and continuity over the lifespan are right. For a typical single-family home with an unshaded roof, a good string inverter is usually the most solid choice. (As of: July 2026)
Key points in brief
- There are three basic designs: string inverters, systems with power optimisers and microinverters.
- The big names in 2026 are Fronius, SMA, Huawei and SolarEdge – plus Kostal, Sungrow and others.
- For unshaded standard roofs, a good string inverter is sufficient; optimisers/microinverters show their strength in the event of shading.
- The design decides the result more than the brand.
- Service presence, spare parts availability and the continuity of the manufacturer count for more over 10 to 15 years than a data sheet detail.
Which types of inverters are there?
Before it comes to brands, it is worth looking at the design – it shapes the result more than the logo. The article The inverter of the solar system explains what an inverter basically does; here are the three approaches in comparison:
| Design | Principle | Strength | typical use |
|---|---|---|---|
| String inverter | a central device for a row of modules | robust, proven, good price-performance ratio | unshaded standard roofs |
| Power optimiser | small electronics per module + central inverter | gets more out of partial shading, module monitoring | shaded or angled roofs |
| Microinverter | one microinverter per module | each module autonomous, no central point of failure | small, heavily shaded or complex roofs |
Rough classification, as of: July 2026. The appropriate design depends on shading, roof shape and budget.
SolarEdge made power optimisers known, Huawei offers similar options in its own ecosystem, Fronius and SMA are classically strong with string inverters. The article Hybrid inverter deals with whether a device can also integrate a battery directly.
Fronius, SMA, Huawei, SolarEdge – who suits what?
All four are established manufacturers with good devices. The differences lie in philosophy, ecosystem and – relevant for the coming years – in the stability of the company.
- Fronius (Austria): strong string specialist with a good reputation for service in the DACH region, solid monitoring software, hybrid options. A classic for standard roofs.
- SMA (Germany): one of the pioneers, proven technology. However, the company is undergoing a major restructuring with a shift in focus towards large systems – a point to keep in mind when choosing.
- Huawei: technologically strong, closed, well-coordinated ecosystem of inverter, battery and wallbox with native surplus charging. For some buyers, the origin is a point of consideration.
- SolarEdge: pioneer of power optimisers with fine module monitoring. The company had a financially turbulent phase and is stabilising – continuity is a factor that a serious comparison names.
The more in-depth duels are covered in two separate articles: Fronius or SMA and Huawei or SolarEdge. How widespread the ecosystems are in Switzerland is shown by the Swissolar Battery Monitor 2026 using the example of energy management: around half of the surveyed installation companies use products from Fronius and Huawei, and Fronius has also strongly increased its presence in batteries (as of: September 2026).
Which inverters does ecoEn install?
We work independently of manufacturers: first we determine the type of construction according to the roof and shading, then the device – with a view to service and replacement over the entire service life. Currently the most frequently requested and offered by us (in no particular order, as of: September 2026):
| Manufacturer | Typical devices | Fits well with |
|---|---|---|
| Huawei | SUN2000 (string/hybrid), combinable with optimisers | Systems with LUNA2000 battery and wallbox from one ecosystem |
| Fronius | Symo, GEN24 Plus (hybrid) | Standard roofs, BYD battery, Wattpilot wallbox |
| SolarEdge | Optimiser systems with SE inverters | shaded or angled roofs |
| Kostal | Plenticore (hybrid), Piko CI (business/apartment building) | Apartment buildings, condominium ownership (STWEG), larger roofs |
| SMA | Sunny Tripower, Sunny Boy | Proven string technology, large systems |
| Sungrow, Sigenergy | String and hybrid devices | Price-conscious or battery-centric projects |
From our projects: Huawei SUN2000 in seven systems from 5 to 100 kW (including Winterthur glider airfield, Uitikon, Zollikon) · Fronius Symo in four systems (including Embrach, Zurich Hofackerstrasse) · Kostal Piko CI 50 and 30 on two condominium ownership (STWEG) roofs in Fällanden · SolarEdge in Ebertswil – key data on the Projects page. You can find the entry point for your roof on the Photovoltaics page.
What really matters when choosing?
Three things count more over the service life than every single data sheet detail:
Fit to the roof situation. An unshaded south or east-west roof does not need optimisers – a good string inverter is more robust and cheaper. Only with partial shading, dormers or angled areas do optimisers and microinverters show their strength.
Service life and replacement. The inverter is the component that you are most likely to replace once over the service life of the system. How long devices last and what the replacement means is covered in the article Service life of the inverter. All the more important: a manufacturer that still exists then and supplies spare parts.
Service and continuity. A good device from a manufacturer without a service presence in Switzerland is of little use in the event of a fault. What to do if the inverter reports errors is shown in the article Inverter fault.
The brand question almost always comes first – although the type of construction is the more important decision. We regularly see quotes with expensive power optimisers for roofs that have no shading at all – where the customer pays for an advantage that will never come into play for them. Conversely, we have roofs with dormers and chimneys where a pure string inverter leaves yield behind. Our sequence: first look at the roof, then determine the type of construction, only then talk about the brand. And when it comes to the brand, we don't just look at the data sheet, but at who will still provide service and supply replacements in ten years' time – for a component that you replace once, that is the decisive question.
Frequently asked questions
Which inverter is the best?
There is not one best one. Fronius, SMA, Huawei and SolarEdge are all established and deliver good devices. More important than the brand is the suitable type of construction for your roof: string for unshaded standard roofs, optimisers or microinverters for shaded or complex areas.
Do I need power optimisers?
Only if your roof is significantly shaded, angled or divided into several orientations. On an unshaded standard roof, optimisers add hardly any value and increase costs and the number of components. A good string inverter is usually the more robust and economical choice there.
Does the financial situation of the manufacturer play a role?
Yes, indirectly. The inverter is often replaced once over the system's operating life and requires service. A manufacturer with a stable presence and a good spare parts supply is therefore an advantage – not as a panic argument, but as one of several points in the comparison.
Can I change the inverter later?
Yes. The inverter is the most easily replaceable component of a system. When replacing, you can also change the make, provided the device is compatible with the system and any battery. This makes the initial choice less final than many think.
Free initial consultation
The right inverter for your roof.
We first determine the type of construction according to your roof situation and then select the device – with a view to service and replacement over the entire service life.
Want to calculate yourself first? Solar calculator with official roof data →
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Swissolar-certified specialist company · ESTI installation authorisation (Art. 14 NIV) · in Zurich since 2017 · over 150 systems completed · a personal answer from the specialist company, no call centre
Sources: Swissolar, Battery Monitor Switzerland 2026 (distribution of energy management and battery brands); manufacturer data sheets and software (Fronius, SMA, Huawei, SolarEdge, Kostal, Sungrow), Swissolar technical information, public reporting on the situation of the manufacturers, empirical values of ecoEn GmbH (Zurich region). As of: July 2026.
Last updated: 9 July 2026 · Author: ecoEn editorial team
