--- title: "Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 650 vs Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 655 - Solar Panel Comparison | ComparePV" description: "Compare Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 650 vs Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 655 side by side: what actually differs, output when it is hot, thirty-year production, and the full specification." source: "https://comparepv.com/compare/q-cells-q-peak-duo-ml-g12s-3-bfg-650/q-cells-q-peak-duo-ml-g12s-3-bfg-655" updated: 2026-09-11 --- # Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 650 vs Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 655 655 leads on the differences that matter The largest is module efficiency: 0.20 pp more efficient. 17 of 18 comparable parameters are identical, with 1 more left out because at least one datasheet does not publish it. ## The two panels | Attribute | A | B | | --- | --- | --- | | Panel | [Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 650](https://comparepv.com/panel/q-cells-q-peak-duo-ml-g12s-3-bfg-650) | [Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 655](https://comparepv.com/panel/q-cells-q-peak-duo-ml-g12s-3-bfg-655) | | Manufacturer | Q-Cells | Q-Cells | | Power | 650 Wp | 655 Wp | | Efficiency | 20.90 % | 21.10 % | | Technology | | | ## Where they differ Ranked by how much the difference matters, not by datasheet order. | Parameter | 650 | 655 | Difference | | --- | --- | --- | --- | | Module efficiency | 20.90 % | 21.10 % | +0.20 pp for 655 | ## Every compared parameter | Parameter | 650 | 655 | | --- | --- | --- | | Rated power | 650 Wp | 655 Wp | | Module efficiency | 20.90 % | 21.10 % | | Power density | 209.2 Wp/m² | 210.9 Wp/m² | | Open-circuit voltage | 45.64 V | 45.66 V | | Voltage at max power | 37.62 V | 37.78 V | | Short-circuit current | 18.30 A | 18.33 A | | Current at max power | 17.28 A | 17.34 A | | Temperature coefficient | -0.340 %/°C | -0.340 %/°C | | Dimensions | 2384x1303x35 mm | 2384x1303x35 mm | | Module area | 3.106 m² | 3.106 m² | | Weight | 38.2 kg | 38.2 kg | | Weight per kWp | 58.8 kg/kWp | 58.3 kg/kWp | | Product warranty | 12 yrs | 12 yrs | | Performance warranty | 30 yrs | 30 yrs | | Annual degradation | 0.45 %/yr | 0.45 %/yr | | Cell technology | - | - | | Cell type | Monocrystalline | Monocrystalline | | Cell count | 132 | 132 | | 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, 650:** 21,405 kWh - **Cumulative output, 655:** 21,570 kWh - **Gap:** 165 kWh ## Output when hot | Condition | Cell temperature | 650 | 655 | Retained | | --- | --- | --- | --- | --- | | Standard test conditions | 25 °C | 650 W | 655 W | 100.0% of rated power | | Cool, bright day | 40 °C | 617 W | 622 W | 94.9% of rated power | | Typical summer roof | 55 °C | 584 W | 588 W | 89.8% of rated power | | Hot roof | 70 °C | 551 W | 555 W | 84.7% of rated power | ## Against the whole database | Measure | 650 | 655 | Out of | Note | | --- | --- | --- | --- | --- | | Efficiency | #10,072 | #9,297 | 14,005 | 655 leads by 775 places | | Power density | #10,011 | #9,459 | 14,005 | 655 leads by 552 places | | Heat behaviour | #8,778 | #8,778 | 14,005 | Tied - the same position in the database | | Weight | #11,891 | #11,654 | 14,005 | 655 leads by 237 places | | Warranty | #21 | #21 | 14,005 | Tied - the same position in the database | | Overall | #3,971 | #3,525 | 14,005 | 655 leads by 446 places | ## Questions ### Which panel is better: Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 650 or Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 655? According to our database: **Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 655** has higher module efficiency (**21.10%** vs **20.90%**). 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 ML-G12S.3 / BFG 650 and Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 655? **Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 650** has a module efficiency of **20.90%**, while **Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 655** 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 ML-G12S.3 / BFG 650 use vs Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 655? **Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 650** uses Monocrystalline cells; **Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 655** uses Monocrystalline. 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 ML-G12S.3 / BFG 650 and Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 655? **Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 650** has a **30 years** power warranty; **Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 655** 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 ML-G12S.3 / BFG 650 and Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 655 bifacial panels? Both **Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 650** and **Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 655** 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 ML-G12S.3 / BFG 650 vs Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 675](https://comparepv.com/compare/q-cells-q-peak-duo-ml-g12s-3-bfg-650/q-cells-q-peak-duo-ml-g12s-3-bfg-675) - 4 differences, the largest is module efficiency - [Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 650 vs Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 670](https://comparepv.com/compare/q-cells-q-peak-duo-ml-g12s-3-bfg-650/q-cells-q-peak-duo-ml-g12s-3-bfg-670) - 3 differences, the largest is module efficiency - [Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 650 vs Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 665](https://comparepv.com/compare/q-cells-q-peak-duo-ml-g12s-3-bfg-650/q-cells-q-peak-duo-ml-g12s-3-bfg-665) - 3 differences, the largest is module efficiency - [Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 650 vs Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 660](https://comparepv.com/compare/q-cells-q-peak-duo-ml-g12s-3-bfg-650/q-cells-q-peak-duo-ml-g12s-3-bfg-660) - 3 differences, the largest is module efficiency - [Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 650 vs Q-Cells Q.TRON XL-G2.3 / BFG 645](https://comparepv.com/compare/q-cells-q-peak-duo-ml-g12s-3-bfg-650/q-cells-q-tron-xl-g2-3-bfg-645) - 13 differences, the largest is module efficiency - [Q-Cells Q.PEAK DUO ML-G12S.3 / BFG 650 vs Q-Cells Q.TRON XL-G2.3 / BFG 640](https://comparepv.com/compare/q-cells-q-peak-duo-ml-g12s-3-bfg-650/q-cells-q-tron-xl-g2-3-bfg-640) - 14 differences, the largest is module efficiency --- Source: https://comparepv.com/compare/q-cells-q-peak-duo-ml-g12s-3-bfg-650/q-cells-q-peak-duo-ml-g12s-3-bfg-655 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.