--- title: "Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585 vs Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 590 - Solar Panel Comparison | ComparePV" description: "Compare Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585 vs Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 590 side by side: what actually differs, output when it is hot, thirty-year production, and the full specification." source: "https://comparepv.com/compare/qcells-hanwha-q-cells-america-inc-q-peak-duo-rsf-xl-g11s-3-bfg-585/qcells-hanwha-q-cells-america-inc-q-peak-duo-rsf-xl-g11s-3-bfg-590" updated: 2026-09-11 --- # Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585 vs Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 590 Identical on every published parameter All 18 comparable parameters agree, with 1 more left out because at least one datasheet does not publish it. Two records this alike are usually one panel sold under two names, or two bins of the same production line - decide on price and on who you would rather buy from. ## The two panels | Attribute | A | B | | --- | --- | --- | | Panel | [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) | [Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 590](https://comparepv.com/panel/qcells-hanwha-q-cells-america-inc-q-peak-duo-rsf-xl-g11s-3-bfg-590) | | Manufacturer | Q-Cells | Q-Cells | | Power | 585 Wp | 590 Wp | | Efficiency | 21.00 % | 21.10 % | | Technology | PERC | PERC | ## Every compared parameter | Parameter | 585 | 590 | | --- | --- | --- | | Rated power | 585 Wp | 590 Wp | | Module efficiency | 21.00 % | 21.10 % | | Power density | 209.5 Wp/m² | 211.3 Wp/m² | | Open-circuit voltage | 53.57 V | 53.60 V | | Voltage at max power | 44.75 V | 44.96 V | | Short-circuit current | 13.72 A | 13.74 A | | Current at max power | 13.07 A | 13.12 A | | Temperature coefficient | -0.340 %/°C | -0.340 %/°C | | Dimensions | 2462x1134x35 mm | 2462x1134x35 mm | | Module area | 2.792 m² | 2.792 m² | | Weight | 36.4 kg | 36.4 kg | | Weight per kWp | 62.2 kg/kWp | 61.7 kg/kWp | | Product warranty | - | - | | Performance warranty | 30 yrs | 30 yrs | | Annual degradation | 0.45 %/yr | 0.45 %/yr | | Cell technology | PERC | PERC | | Cell type | Monocrystalline | Monocrystalline | | Cell count | 156 | 156 | | Bifacial | Yes | Yes | ## Thirty-year yield Each panel's own declared degradation curve, at 1,200 kWh/kWp a year Same temp coeff. for both panels (-0.340 %/°C), so a warmer roof scales both curves by the same factor: the totals fall together and neither panel gains on the other. - **Cumulative output, 585:** 19,265 kWh - **Cumulative output, 590:** 19,429 kWh - **Gap:** 164 kWh ## Output when hot | Condition | Cell temperature | 585 | 590 | Retained | | --- | --- | --- | --- | --- | | Standard test conditions | 25 °C | 585 W | 590 W | 100.0% of rated power | | Cool, bright day | 40 °C | 555 W | 560 W | 94.9% of rated power | | Typical summer roof | 55 °C | 525 W | 530 W | 89.8% of rated power | | Hot roof | 70 °C | 495 W | 500 W | 84.7% of rated power | ## Against the whole database | Measure | 585 | 590 | Out of | Note | | --- | --- | --- | --- | --- | | Efficiency | #9,758 | #9,297 | 14,005 | 590 leads by 461 places | | Power density | #9,941 | #9,241 | 14,005 | 590 leads by 700 places | | Heat behaviour | #8,778 | #8,778 | 14,005 | Tied - the same position in the database | | Weight | #12,754 | #12,677 | 14,005 | 590 leads by 77 places | | Warranty | #21 | #21 | 14,005 | Tied - the same position in the database | | Overall | #8,794 | #8,523 | 14,005 | 590 leads by 271 places | ## Questions ### Which panel is better: Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585 or Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 590? According to our database: **Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 590** has higher module efficiency (**21.10%** vs **21.00%**). See the full spec comparison and 30-year energy simulation above for a complete picture. ### What is the efficiency of Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585 and Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 590? **Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585** has a module efficiency of **21.00%**, while **Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 590** is **21.10%**. Higher efficiency means more electricity from the same roof area - useful when space is limited. ### What cell technology does Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585 use vs Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 590? **Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585** uses **PERC** cells; **Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 590** uses **PERC**. Modern **n-type** technologies (**TOPCon**, **HJT**, BC) typically deliver higher efficiency and lower degradation compared to older **PERC** (p-type) cells. ### What is the warranty on Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585 and Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 590? **Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585** has a **30 years** power warranty; **Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 590** has a **30 years** power warranty. The power warranty guarantees a minimum percentage of rated output at the end of the warranty period (typically 80**-87%**). Product (materials) warranties are usually shorter. ### Are Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585 and Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 590 bifacial panels? Both **Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585** and **Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 590** are bifacial - they capture reflected light from the ground, which can add 5**-15%** more annual energy on ground-mount or elevated rooftop installations with a light surface beneath. ## Related comparisons - [Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585 vs Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 600](https://comparepv.com/compare/qcells-hanwha-q-cells-america-inc-q-peak-duo-rsf-xl-g11s-3-bfg-585/qcells-hanwha-q-cells-america-inc-q-peak-duo-rsf-xl-g11s-3-bfg-600) - 3 differences, the largest is module efficiency - [Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585 vs Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 595](https://comparepv.com/compare/qcells-hanwha-q-cells-america-inc-q-peak-duo-rsf-xl-g11s-3-bfg-585/qcells-hanwha-q-cells-america-inc-q-peak-duo-rsf-xl-g11s-3-bfg-595) - 3 differences, the largest is module efficiency - [Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585 vs Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 675](https://comparepv.com/compare/qcells-hanwha-q-cells-america-inc-q-peak-duo-rsf-xl-g11s-3-bfg-585/q-cells-q-peak-duo-ml-g12s-3-bfg-675) - 12 differences, the largest is module efficiency - [Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585 vs Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 670](https://comparepv.com/compare/qcells-hanwha-q-cells-america-inc-q-peak-duo-rsf-xl-g11s-3-bfg-585/q-cells-q-peak-duo-ml-g12s-3-bfg-670) - 12 differences, the largest is rated power - [Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585 vs Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 665](https://comparepv.com/compare/qcells-hanwha-q-cells-america-inc-q-peak-duo-rsf-xl-g11s-3-bfg-585/q-cells-q-peak-duo-ml-g12s-3-bfg-665) - 12 differences, the largest is rated power - [Q-Cells Q.PEAK DUO RSF XL-G11S.3 / BFG 585 vs Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 660](https://comparepv.com/compare/qcells-hanwha-q-cells-america-inc-q-peak-duo-rsf-xl-g11s-3-bfg-585/q-cells-q-peak-duo-ml-g12s-3-bfg-660) - 11 differences, the largest is rated power --- Source: https://comparepv.com/compare/qcells-hanwha-q-cells-america-inc-q-peak-duo-rsf-xl-g11s-3-bfg-585/qcells-hanwha-q-cells-america-inc-q-peak-duo-rsf-xl-g11s-3-bfg-590 Not in this file, on the page: the thirty-year yield curve year by year at a cell temperature you pick and a written summary generated on request.