--- title: "Viessmann Solar Panels Review 2026: Pros, Cons & Specs | ComparePV" description: "In-depth Viessmann solar panel review 2026. 11 models analyzed: efficiency, cell technology, warranty, top picks. Compare Viessmann panels on ComparePV." source: "https://comparepv.com/reviews/viessmann" --- # Viessmann panels, *read off the datasheets* Viessmann has 11 modules in the database, from 255 to 405 Wp. Everything below is computed from those 11 datasheets: no score out of ten, no ranking of brands against each other, and nothing a manufacturer can pay to change. Where Viessmann does not publish a figure, it is left out of the average rather than assumed. ## The company - **Founded:** 1917 - **Headquarters:** Allendorf, Germany Company facts, not datasheet figures. Tier 1 is a financier's bankability list, and says nothing about how a panel performs. ## Key figures | Measure | Value | Note | | --- | --- | --- | | Panels | 11 | models in the database | | Average efficiency | 19.4 % | across the catalogue | | Best efficiency | 21.3 % | their strongest module | | Power range | 255-405 Wp | smallest to largest | | Bifacial share | 0 % | 0 dual-sided models | | Average warranty | 25 years | guaranteed output term | ## 01. The top of the range The leaders of Viessmann's own catalogue on the two figures a specification sheet leads with. Neither is a verdict: the most efficient module in a range is rarely the one that suits a given roof. ### Most efficient module efficiency | # | Panel | power | efficiency | | --- | --- | --- | --- | | 1 | [M400WG](https://comparepv.com/panel/viessmann-m400wg) | 400 Wp | 21.3% | | 2 | [M395WG](https://comparepv.com/panel/viessmann-m395wg) | 395 Wp | 21.1% | | 3 | [M390WG](https://comparepv.com/panel/viessmann-m390wg) | 390 Wp | 20.8% | | 4 | [M405WE](https://comparepv.com/panel/viessmann-m405we) | 405 Wp | 20.7% | | 5 | [M405WK](https://comparepv.com/panel/viessmann-m405wk) | 405 Wp | 20.7% | - M400WG - Monocrystalline - M395WG - Monocrystalline - M390WG - Monocrystalline - M405WE - Monocrystalline - M405WK - Monocrystalline [Sort the whole catalogue by efficiency](https://comparepv.com/panels/viessmann?sort_by=efficiency&sort_order=desc) ### Highest power nameplate output | # | Panel | efficiency | power | | --- | --- | --- | --- | | 1 | [M405WE](https://comparepv.com/panel/viessmann-m405we) | 20.7% | 405 Wp | | 2 | [M405WK](https://comparepv.com/panel/viessmann-m405wk) | 20.7% | 405 Wp | | 3 | [M400WG](https://comparepv.com/panel/viessmann-m400wg) | 21.3% | 400 Wp | | 4 | [M400WE](https://comparepv.com/panel/viessmann-m400we) | 20.4% | 400 Wp | | 5 | [M400WK](https://comparepv.com/panel/viessmann-m400wk) | 20.4% | 400 Wp | - M405WE - Monocrystalline - M405WK - Monocrystalline - M400WG - Monocrystalline - M400WE - Monocrystalline - M400WK - Monocrystalline [Sort the whole catalogue by power](https://comparepv.com/panels/viessmann?sort_by=power&sort_order=desc) ## 02. By what the array is for Three cuts of the same catalogue, each ordered by efficiency inside its band. An empty column means the brand does not build for that case. ### For a house roof 380-460 Wp | # | Panel | power | efficiency | | --- | --- | --- | --- | | 1 | [M400WG](https://comparepv.com/panel/viessmann-m400wg) | 400 Wp | 21.3% | | 2 | [M395WG](https://comparepv.com/panel/viessmann-m395wg) | 395 Wp | 21.1% | | 3 | [M390WG](https://comparepv.com/panel/viessmann-m390wg) | 390 Wp | 20.8% | | 4 | [M405WE](https://comparepv.com/panel/viessmann-m405we) | 405 Wp | 20.7% | | 5 | [M405WK](https://comparepv.com/panel/viessmann-m405wk) | 405 Wp | 20.7% | - M400WG - Monocrystalline - M395WG - Monocrystalline - M390WG - Monocrystalline - M405WE - Monocrystalline - M405WK - Monocrystalline ## 03. What the catalogue is made of Shares are of the 11 modules in the database, counted once each. A power ladder of one module counts as its rungs, which is why a large catalogue is not the same as a wide one. [Cell technology across the market](https://comparepv.com/stats/cell-technology) ### Cell technology share of the catalogue | # | Panel | share | panels | | --- | --- | --- | --- | | | PERC | 72.7% | 8 | | | Unknown | 27.3% | 3 | PERC accounts for 72.7% of the catalogue - 8 of 11 modules. ### Efficiency spread share of the catalogue | # | Panel | share | panels | | --- | --- | --- | --- | | | \<20% | 27.3% | 3 | | | 20-21% | 54.5% | 6 | | | 21-22% | 18.2% | 2 | ## 04. Strengths and gaps Both lists are derived from the figures above rather than written about the brand. A gap here is a gap in what is published, which is not always a gap in what is built. ### What this catalogue is good at - **Strength:** Strong warranty coverage averaging 25 years - **Strength:** Established manufacturer with 109+ years of experience ### Where it is thin - **Watch out:** Average efficiency of 19.4% is below the industry leading edge - **Watch out:** Limited bifacial panel options - **Watch out:** No high-power panels (500W+) available for commercial use - **Watch out:** Limited adoption of latest cell technologies (TOPCon/HJT) ## 05. In short > **Viessmann:** Viessmann is a solid option, offering 11 panels suitable for residential installations. With an average efficiency of 19.4% and top models reaching 21.3%, their panels deliver competitive performance. ### Common questions #### Is Viessmann a good solar panel manufacturer? Viessmann offers 11 solar panel models with an average efficiency of 19.4%. Check their full panel lineup on ComparePV to find the best model for your needs. #### What types of solar panels does Viessmann make? Viessmann manufactures panels ranging from 255W to 405W, covering both residential and commercial applications. Their portfolio includes PERC (73%), Unknown (27%) cell technologies. #### How efficient are Viessmann solar panels? Viessmann panels have an average efficiency of 19.4%, with their most efficient model reaching 21.3%. This puts them at a solid mid-range level in the current market. #### What warranty does Viessmann offer on their solar panels? Viessmann panels come with an average performance warranty of 25 years. This warranty guarantees that the panels will maintain a specified level of power output over time, protecting your investment against degradation beyond normal levels. #### Are Viessmann panels good for residential use? Viessmann offers panels in the residential-friendly 380-460W range. For home installations, look for models with high efficiency and compact dimensions to maximize power from limited roof space. Browse their full lineup on ComparePV to filter by power range and specifications. ## 06. Compared with A brand comparison weighs the two catalogues against each other - what each builds, at what efficiency, and how deep the range goes. [Build your own](https://comparepv.com/comparisons) - [Viessmann vs Jinko Solar](https://comparepv.com/jinko-solar-vs-viessmann) - [Viessmann vs JA Solar](https://comparepv.com/ja-solar-vs-viessmann) - [Viessmann vs Trina Solar](https://comparepv.com/trina-solar-vs-viessmann) - [Viessmann vs LONGi](https://comparepv.com/longi-vs-viessmann) - [Viessmann vs Canadian Solar](https://comparepv.com/canadian-solar-vs-viessmann) - [Viessmann vs Q-Cells](https://comparepv.com/q-cells-vs-viessmann) - [Viessmann vs AIKO](https://comparepv.com/aiko-vs-viessmann) - [Viessmann vs Hyundai](https://comparepv.com/hyundai-vs-viessmann) ## Elsewhere - [All Viessmann panels 11](https://comparepv.com/panels/viessmann) - [All manufacturers](https://comparepv.com/reviews) - [Panel database](https://comparepv.com/panels) - [Market statistics](https://comparepv.com/stats) --- Source: https://comparepv.com/reviews/viessmann