---
title: "Q-Cells vs Viessmann - Brand Comparison | ComparePV"
description: "Compare Q-Cells vs Viessmann solar panels: full portfolio, efficiency, cell technology breakdown, warranty terms and company background."
source: "https://comparepv.com/q-cells-vs-viessmann"
---

# Q-Cells vs Viessmann

Q-Cells has the broader catalog (89 vs 11 models). Q-Cells leads on peak efficiency at 23.20%. Q-Cells leans bifacial (39% of lineup).


## The two companies


| Attribute | Q-Cells | Viessmann |
| --- | --- | --- |
| Country | South Korea | Germany |
| Headquarters | Seoul | Allendorf |
| Founded | 1999 | 1917 |
| Employees | 2000+ |  |
| Annual capacity | 11.2 GW/year |  |
| Tier 1 | yes | no |
| Listed | NASDAQ: HQCL |  |
| Website | [https://www.qcells.com](https://www.qcells.com) | [https://www.viessmann.com](https://www.viessmann.com) |

Qcells is a renowned global provider of complete energy solutions, specializing in solar cells and modules, energy storage solutions, downstream project business, and energy retail. The company has a strong heritage dating back to its foundation in Germany and has become a leader in technology innovations. As an...


## Catalog & Power


| Measure | Q-Cells | Viessmann | Margin |
| --- | --- | --- | --- |
| Panel Models | 89 | 11 | +78 |
| Max Power | 675 W | 405 W | +270 W |
| Avg Power | 468 W | 361 W | +107 W |


## Efficiency


| Measure | Q-Cells | Viessmann | Margin |
| --- | --- | --- | --- |
| Max Efficiency | 23.20% | 21.30% | +1.90 pp |
| Avg Efficiency | 21.21% | 19.41% | +1.80 pp |


## Reliability & Warranty


| Measure | Q-Cells | Viessmann | Margin |
| --- | --- | --- | --- |
| Avg Temp Coefficient | -0.325%/°C | -0.362%/°C | +0.037 |
| Bifacial Share | 35 (39%) | 0 (0%) | +39 pp |
| Avg Warranty | 27.0 yrs | 25.0 yrs | +2.0 yr |


## Efficiency distribution

Q-Cells skews to higher efficiency: 2% of lineup is 23%+


| Efficiency band | Q-Cells | Viessmann |
| --- | --- | --- |
| \<20% | 7 (7.9%) | 3 (27.3%) |
| 20-21% | 29 (32.6%) | 6 (54.5%) |
| 21-22% | 30 (33.7%) | 2 (18.2%) |
| 22-23% | 21 (23.6%) | 0 |
| 23%+ | 2 (2.2%) | 0 |


## Power distribution

Q-Cells offers more 600W+ panels (19% of lineup)


| Power band | Q-Cells | Viessmann |
| --- | --- | --- |
| \<400W | 20 (22.5%) | 6 (54.5%) |
| 400-499W | 41 (46.1%) | 5 (45.5%) |
| 500-599W | 11 (12.4%) | 0 |
| 600-699W | 17 (19.1%) | 0 |


## Cell technology

Dominant cell tech: **PERC** (43%)

Dominant cell tech: **PERC** (73%)


| Technology | Q-Cells | Viessmann |
| --- | --- | --- |
| PERC | 38 (42.7%) | 8 (72.7%) |
| N-type | 23 (25.8%) | 0 |
| Unknown | 20 (22.5%) | 3 (27.3%) |
| TOPCon | 8 (9.0%) | 0 |


## Top panels, Q-Cells


| # | Model | Power | Efficiency | Temp. coefficient | Technology |
| --- | --- | --- | --- | --- | --- |
| 1 | [Q.PEAK DUO ML-G12S.3 / BFG 675](https://comparepv.com/panel/q-cells-q-peak-duo-ml-g12s-3-bfg-675) | 675 | 21.7 | -0.340 | Monocrystalline |
| 2 | [Q.PEAK DUO ML-G12S.3 / BFG 670](https://comparepv.com/panel/q-cells-q-peak-duo-ml-g12s-3-bfg-670) | 670 | 21.6 | -0.340 | Monocrystalline |
| 3 | [Q.PEAK DUO ML-G12S.3 / BFG 665](https://comparepv.com/panel/q-cells-q-peak-duo-ml-g12s-3-bfg-665) | 665 | 21.4 | -0.340 | Monocrystalline |
| 4 | [Q.PEAK DUO ML-G12S.3 / BFG 660](https://comparepv.com/panel/q-cells-q-peak-duo-ml-g12s-3-bfg-660) | 660 | 21.2 | -0.340 | Monocrystalline |
| 5 | [Q.PEAK DUO ML-G12S.3 / BFG 655](https://comparepv.com/panel/q-cells-q-peak-duo-ml-g12s-3-bfg-655) | 655 | 21.1 | -0.340 | Monocrystalline |
| 6 | [Q.PEAK DUO ML-G12S.3 / BFG 650](https://comparepv.com/panel/q-cells-q-peak-duo-ml-g12s-3-bfg-650) | 650 | 20.9 | -0.340 | Monocrystalline |
| 7 | [Q.TRON XL-G2.3 / BFG 645](https://comparepv.com/panel/q-cells-q-tron-xl-g2-3-bfg-645) | 645 | 23.1 | -0.290 | Monocrystalline |
| 8 | [Q.TRON XL-G2.3 / BFG 640](https://comparepv.com/panel/q-cells-q-tron-xl-g2-3-bfg-640) | 640 | 22.9 | -0.290 | Monocrystalline |
| 9 | [Q.TRON XL-G2.3 / BFG 635](https://comparepv.com/panel/hanwha-q-cells-america-inc-q-tron-xl-g2-3-bfg-635) | 635 | 22.7 | -0.300 | Monocrystalline |
| 10 | [Q.TRON XL-G2.3 / BFG 630](https://comparepv.com/panel/hanwha-q-cells-america-inc-q-tron-xl-g2-3-bfg-630) | 630 | 22.6 | -0.300 | Monocrystalline |


## Top panels, Viessmann


| # | Model | Power | Efficiency | Temp. coefficient | Technology |
| --- | --- | --- | --- | --- | --- |
| 1 | [M405WE](https://comparepv.com/panel/viessmann-m405we) | 405 | 20.7 | -0.340 | Monocrystalline |
| 2 | [M405WK](https://comparepv.com/panel/viessmann-m405wk) | 405 | 20.7 | -0.340 | Monocrystalline |
| 3 | [M400WG](https://comparepv.com/panel/viessmann-m400wg) | 400 | 21.3 | -0.340 | Monocrystalline |
| 4 | [M400WE](https://comparepv.com/panel/viessmann-m400we) | 400 | 20.4 | -0.340 | Monocrystalline |
| 5 | [M400WK](https://comparepv.com/panel/viessmann-m400wk) | 400 | 20.4 | -0.340 | Monocrystalline |
| 6 | [M395WG](https://comparepv.com/panel/viessmann-m395wg) | 395 | 21.1 | -0.340 | Monocrystalline |
| 7 | [M395WK](https://comparepv.com/panel/viessmann-m395wk) | 395 | 20.1 | -0.340 | Monocrystalline |
| 8 | [M390WG](https://comparepv.com/panel/viessmann-m390wg) | 390 | 20.8 | -0.340 | Monocrystalline |
| 9 | [P265PGHC](https://comparepv.com/panel/viessmann-p265pghc) | 265 | 16.3 | -0.420 | Polycrystalline |
| 10 | [P260PGHC](https://comparepv.com/panel/viessmann-p260pghc) | 260 | 16.0 | -0.420 | Polycrystalline |


## Summary

Q-Cells traces its roots to Germany, where it was founded in 1999 in Bitterfeld-Wolfen before being acquired in 2012 by South Korea's Hanwha Group and operating today as the Hanwha Qcells Division. The brand holds BloombergNEF Tier 1 bankability status and operates what it describes as the largest solar manufacturing facility in the Western Hemisphere, located in Dalton, Georgia, with combined global annual capacity reported at around 11 GW. Viessmann is a German heating and energy systems conglomerate founded in 1917 and headquartered in Allendorf (Eder), with solar PV representing one segment of a broader portfolio spanning heat pumps, boilers, and home energy management. Viessmann's solar division does not appear on published BloombergNEF Tier 1 module-maker lists, and the company does not publish a comparable GW-scale production figure. On institutional scale and bankability, Hanwha Q-Cells has the demonstrably stronger footprint.

Hanwha Q-Cells addresses both residential and commercial buyers through two main module families: the Q.TRON series, built on TOPCon cell technology with efficiency cited at up to around 23.7% on high-output variants, and the Q.PEAK DUO series, a PERC-based line at more moderate price points. Its US manufacturing base and Tier 1 standing make it a widely specified choice for installers on both rooftop and mid-scale commercial projects. Viessmann's solar offer centers on the Vitovolt 300 range, where newer bifacial models use N-type TOPCon cells and reach up to 445 Wp per product data, alongside an older PERC line. Viessmann's real competitive edge is system integration - its panels are designed to pair with Viessmann heat pumps and home energy storage, giving the brand particular traction in European residential markets and earning it the EUPD Top Brand PV designation in Germany.

For buyers seeking standalone solar panels - whether for a US rooftop or a mid-scale commercial system - Hanwha Q-Cells is the clearer default in 2025, backed by confirmed Tier 1 bankability, a domestic US manufacturing option, and broad installer support. Viessmann becomes more compelling for European homeowners already committed to the Viessmann heating ecosystem, where integrated PV-and-heat-pump packages add genuine value. Outside that scenario the two brands are not interchangeable: Q-Cells is a dedicated solar manufacturer operating at scale, while Viessmann treats solar as one component among many.

\---LINKS---

\- https://www.solarreviews.com/blog/hanwha-q-cells-solar-panels-complete-review \| Hanwha Q CELLS Solar Panels - Expert Review \| review

\- https://www.energysage.com/solar/best-solar-panels-complete-ranking/q-cells-solar-panels-complete-review/ \| Q CELLS Solar Panels Complete Review - EnergySage \| review

\- https://www.energysage.com/supplier/201/viessmann/ \| Viessmann Solar - Profile and Reviews - EnergySage \| review

\- https://www.pv-magazine.com/2021/09/13/hanwha-q-cells-unveils-plan-to-produce-perovskite-topcon-solar-modules/ \| Hanwha Q Cells TOPCon and perovskite module plans - PV Magazine \| article

Sources:

\- \[Hanwha Q CELLS Solar Panels - Expert Review (SolarReviews)\](https://www.solarreviews.com/blog/hanwha-q-cells-solar-panels-complete-review)

\- \[Q CELLS Solar Panels Complete Review - EnergySage\](https://www.energysage.com/solar/best-solar-panels-complete-ranking/q-cells-solar-panels-complete-review/)

\- \[Viessmann Solar - Profile and Reviews - EnergySage\](https://www.energysage.com/supplier/201/viessmann/)

\- \[Hanwha Q Cells TOPCon and perovskite module plans - PV Magazine\](https://www.pv-magazine.com/2021/09/13/hanwha-q-cells-unveils-plan-to-produce-perovskite-topcon-solar-modules/)

Written by claude-sonnet from the figures above.


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- [ARTsolar vs Viessmann](https://comparepv.com/artsolar-vs-viessmann)


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Source: https://comparepv.com/q-cells-vs-viessmann

Not in this file, on the page: the distributions above drawn as charts.