--- title: "Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 590 590W Solar Panel - Specs & Review | ComparePV" description: "Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 590 590W solar panel. Specs: 21.10% efficiency, Monocrystalline cells, dimensions, warranty and temperature coefficient." source: "https://comparepv.com/panel/qcells-hanwha-q-cells-america-inc-q-peak-duo-xl-g11s-3-bfg-590" updated: 2026-09-11 --- # Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 590 Warranty pick, heavy for its output 589 panels in the segment PERC 550-600 W ## Identity - **Manufacturer:** Q-Cells - **Model:** Q.PEAK DUO XL-G11S.3 / BFG 590 - **Series:** Q.PEAK DUO XL-G11S SERIES - **Rated power:** 590 W - **Cell technology:** PERC - **Bifacial:** yes ## How it compares Compared against segment PERC 550-600 W (589 panels). | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Power (Wp) | 590 W | 560 W | Strong - top 17% | | | Module efficiency | 21.10% | 21.29% | Typical | 9,297 | | Power density | 211.3 | 212.9 | Typical | 9,241 | | Temperature coefficient | -0.340 | -0.350 | Typical | 8,778 | | Weight (kg) | 34.9 kg | 30.8 kg | Weak - bottom 13% | | | Performance warranty | 30 yrs | 27 yrs | Strong - top 25% | 21 | ### Full peer table | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Module efficiency | 21.10% | 21.29% | Typical | 9,297 | | Power density | 211.3 | 212.9 | Typical | 9,241 | | Temperature coefficient | -0.340 | -0.350 | Typical | 8,778 | | Weight per kWp | 59.2 | 52.7 | Weak - bottom 13% | 12,036 | | Performance warranty | 30 yrs | 27 yrs | Strong - top 25% | 21 | ### Strengths - **30 year performance warranty** - Top 25% of the PERC 550-600 W segment, against a median of 27 yrs. ### Watch out for - **59.2 kg per kWp** - Bottom 13% of the PERC 550-600 W segment, against a median of 52.7. - **Best for:** Commercial, utility-scale and shaded-installations. - **Not ideal for:** Weight-limited structures. ## Specification ### Electrical - **Rated power (Pmax):** 590 W - **Efficiency:** 21.10 % - **Voltage at Pmax (Vmp):** 44.96 V - **Current at Pmax (Imp):** 13.12 A - **Open-circuit voltage (Voc):** 53.60 V - **Short-circuit current (Isc):** 13.74 A - **Max system voltage:** 1500 V ### Temperature - **Temperature coefficient of Pmax:** -0.340 %/degC - **Temperature coefficient of Voc:** -0.270 %/degC - **Temperature coefficient of Isc:** 0.040 %/degC - **NOCT:** 42 degC ### Cell and construction - **Cell type:** Monocrystalline - **Cell technology:** PERC - **Cell count:** 156 - **Bifacial:** yes - **Bifacial gain:** 21.00 ### Physical - **Length:** 2462 mm - **Width:** 1134 mm - **Thickness:** 35 mm - **Weight:** 34.9 kg - **Area:** 2.79 m2 - **Power density:** 211.3 Wp/m2 ### Warranty and degradation - **Product warranty:** 12 years - **Performance warranty:** 30 years - **Output guaranteed at end of warranty:** 85.0 % - **First-year degradation:** 2.00 % - **Annual degradation:** 0.45 % - **Output after 30 years:** 501 W ## Rank in the whole catalogue | Measure | Position | | --- | --- | | Efficiency | 9297 of 14005 | | Power density | 9241 of 14005 | | Temperature coefficient | 8778 of 14005 | | Weight | 12036 of 14005 | | Warranty | 21 of 14005 | ## Pros - **Double-glass bifacial construction** - The glass-glass design combined with Q.ANTUM DUO technology captures light reflected off the ground, delivering up to 20% additional rear-side energy yield compared to conventional monofacial modules - especially relevant for ground-mount and tracker installations. - **Tier-1 bankable manufacturer** - Q-Cells is a South Korean manufacturer (Hanwha Group, founded 1999) with BNEF Tier-1 status, which directly matters for financing commercial and utility-scale projects, as banks and investors more readily accept the brand as loan collateral. - **30-year power warranty at 84.95%** - The manufacturer guarantees 93.95% power output after 10 years and 84.95% after 30 years, providing a predictable, near-linear degradation profile that is critical for investors planning a three-decade project payback. - **Low -0.34%/°C temperature coefficient** - The half-cut format in Q.ANTUM DUO technology reduces partial-shading losses, and a Pmax temperature coefficient of -0.34%/°C means smaller output drops in hot conditions than many conventional PERC modules in the same segment. - **Assembled in the USA** - Modules are assembled in the United States, which for US-based projects eases compliance with domestic content requirements and can reduce tariff exposure compared to modules imported from Asia. ## Cons - **Production discontinued in 2025** - The Q.PEAK DUO XL-G11S series has been discontinued (released 2022, end-of-production 2025), meaning limited availability of warranty service and spare parts, and added difficulty completing large, multi-year installations with a single module type. - **PERC efficiency trails newer N-type models** - The maximum efficiency of 21.7% is notably lower than the competing GCL SIROT Efficient NT10/72GDF (23.42% at the same 605 Wp power class, N-type technology), meaning lower yield per square meter of roof or ground area. - **Module weight increases BoS costs** - The double-glass construction weighs about 34.9 kg at 2462x1134 mm dimensions, notably heavier than lighter framed monoglass panels - this can raise racking and logistics costs on large-scale PV farms. ## About this series The Q-Cells Q.PEAK DUO XL-G11S series are bifacial modules in a double glass configuration, designed for commercial installations and PV farms where maximizing energy yield from the same surface area and predictable long-term production are key. Thanks to the **double-sided construction**, the panel can also utilize reflected light from the ground, effectively boosting energy production in ground-mounted systems and trackers, thereby reducing the cost of producing 1 kWh. Against the backdrop of numerous competitive modules, it stands out with the **Q.ANTUM DUO technology** featuring a modern cell connection method and half-cell format, which minimizes losses and improves performance under partial shading. In practice, this addresses typical issues in large installations - uneven irradiance, operation under poorer light conditions, and yield drops at high temperatures. Another advantage is the **weather-resistant structure** and load-bearing capacity, as well as the **long warranty package**, which is important for investors, developers, and companies expecting stable project parameters for years to come. ## Notable figures - Efficiency of 21.1% matches the \*\*PERC 550-600W\*\* median - Power density of 211.3 W/m² matches the \*\*PERC 550-600W\*\* median - At -0.34%/°C, hot weather performance is typical for \*\*PERC 550-600W\*\* panels - Weight of 34.9 kg is 4.1 kg above \*\*PERC 550-600W\*\* median (30.8 kg) - verify structural support - Bifacial design (70% factor) captures reflected light - adds 4-10% yield on ground-mount or white roof ## Questions ### Is the Q.PEAK DUO XL-G11S series still available for purchase? The Q.PEAK DUO XL-G11S series has been discontinued — Q-Cells has replaced it with newer module generations. Availability at distributors may be limited to remaining stock. If you need Q-Cells panels with similar specs for a commercial project, ask your distributor about current equivalents from the Q.PEAK DUO or Q.TRON lineup. ### What warranty does the Q.PEAK DUO XL-G11S series carry? The Q.PEAK DUO XL-G11S series comes with a 12-year product warranty and a 30-year linear power warranty — after 30 years, the panel is guaranteed to retain at least 84.95% of its nominal power output. This is one of the longer warranty packages in the bifacial commercial module segment, an important factor for project financing and long-term yield forecasting. ### What does Q.ANTUM DUO technology bring to the Q.PEAK DUO XL-G11S series? Q.ANTUM DUO combines PERC cells in a half-cut format (156 cells) with an optimized multi-busbar layout. The half-cut design reduces resistive losses and improves shading tolerance, while PERC increases light absorption. The result is module efficiency up to 21.7% and better energy yield under low-irradiance and diffuse-light conditions. ### Is the Q.PEAK DUO XL-G11S suitable for ground-mounted systems with single-axis trackers? Yes, the XL-G11S series is purpose-built for utility-scale and commercial PV plants. The bifacial double-glass construction captures energy from both module sides — on a single-axis tracker or over a reflective ground surface, rear-side gain can add several percentage points of additional yield. The aluminum frame is rated for 5,400 Pa snow load and 3,750 Pa wind load. ### How does high ambient temperature affect Q.PEAK DUO XL-G11S output? The temperature coefficient for Pmax is -0.34%/°C. At a realistic summer module temperature of 65°C, power loss relative to STC conditions is approximately 8.5%. This is a moderate result for PERC-class cells — the double-glass rear side also aids heat dissipation compared with conventional back-sheet modules. ### How heavy is the Q.PEAK DUO XL-G11S and does it work on an industrial rooftop? The module weighs 34.9 kg with dimensions of 2,462×1,134×35 mm, delivering up to 605 Wp. This XL large-format panel is designed primarily for industrial rooftops and utility-scale PV plants where mechanical handling equipment is available. For rooftop use, the mounting structure must be engineered to support the additional weight of the double-glass construction. ## Datasheet [Manufacturer datasheet (PDF)](https://comparepv.com/datasheets/qcells-data-sheet-q-peak-duo-xl-g11s-bfg-series-590-605-2024-ab9ed989c8aa.pdf) ## Alternatives | Panel | Power | How it differs | | --- | --- | --- | | [Longi Solar LR7-60HVH-560M](https://comparepv.com/panel/longi-lr7-60hvh-560m) | 560 W | Cooler, lighter, +3.7 pp | | [AIKO AIKO-A640-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a640-mae72mw) | 640 W | Cooler, lighter, +3.7 pp | | [Longi Solar LR7-60HVH-555M](https://comparepv.com/panel/longi-lr7-60hvh-555m) | 555 W | Cooler, lighter, +3.5 pp | | [AIKO AIKO-A635-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a635-mae72mw) | 635 W | Cooler, lighter, +3.5 pp | | [AIKO AIKO-A630-MAH72Dw](https://comparepv.com/panel/aiko-aiko-a630-mah72dw) | 630 W | +40 W, cooler, +3.3 pp | | [Longi Solar LR7-60HVHL-550M](https://comparepv.com/panel/longi-lr7-60hvhl-550m) | 550 W | Cooler, 19 kg lighter, +3.3 pp | | [Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 580](https://comparepv.com/panel/q-cells-q-peak-duo-xl-g11s-3-bfg-580) | 580 W | -10 W, -0.3 pp | | [Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585](https://comparepv.com/panel/qcells-hanwha-q-cells-america-inc-q-peak-duo-rsf-xl-g11s-3-bfg-585) | 585 W | Heavier | | [Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 595](https://comparepv.com/panel/qcells-hanwha-q-cells-america-inc-q-peak-duo-rsf-xl-g11s-3-bfg-595) | 595 W | Heavier | | [Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 600](https://comparepv.com/panel/qcells-hanwha-q-cells-america-inc-q-peak-duo-rsf-xl-g11s-3-bfg-600) | 600 W | +10 W, heavier, +0.4 pp | | [Q-Cells Q.PEAK DUO XL-G11S.3 / BFG 605](https://comparepv.com/panel/qcells-hanwha-q-cells-america-inc-q-peak-duo-xl-g11s-3-bfg-605) | 605 W | +15 W, +0.6 pp | | [AIKO AIKO-A680-MDE72Mw](https://comparepv.com/panel/aiko-aiko-a680-mde72mw) | 680 W | +90 W, cooler, +4.1 pp | | [AIKO AIKO-A675-MDE72Mw](https://comparepv.com/panel/aiko-aiko-a675-mde72mw) | 675 W | +85 W, cooler, +3.9 pp | | [AIKO AIKO-A700-MAE78Dw](https://comparepv.com/panel/aiko-aiko-a700-mae78dw) | 700 W | +110 W, cooler, +3.9 pp | | [AIKO AIKO-A695-MAE78Dw](https://comparepv.com/panel/aiko-aiko-a695-mae78dw) | 695 W | +105 W, cooler, +3.8 pp | | [AIKO AIKO-G670-MCH72Mw](https://comparepv.com/panel/aiko-aiko-g670-mch72mw) | 670 W | +80 W, cooler, +3.7 pp | --- Source: https://comparepv.com/panel/qcells-hanwha-q-cells-america-inc-q-peak-duo-xl-g11s-3-bfg-590 Not in this file, on the page: a thirty-year output simulator, a bifacial gain calculator and alternatives filtered by how closely they match these dimensions.