--- title: "Silfab SIL-520 QM vs Silfab SIL-590 XM+ - Solar Panel Comparison | ComparePV" description: "Compare Silfab SIL-520 QM vs Silfab SIL-590 XM+ side by side: what actually differs, output when it is hot, thirty-year production, and the full specification." source: "https://comparepv.com/compare/silfab-sil-520-qm/silfab-sil-590-xm" updated: 2026-09-11 --- # Silfab SIL-520 QM vs Silfab SIL-590 XM+ 590 XM+ leads on the differences that matter The largest is module efficiency: 0.90 pp more efficient. 8 of 19 comparable parameters are identical. ## The two panels | Attribute | A | B | | --- | --- | --- | | Panel | [Silfab SIL-520 QM](https://comparepv.com/panel/silfab-sil-520-qm) | [Silfab SIL-590 XM+](https://comparepv.com/panel/silfab-sil-590-xm) | | Manufacturer | Silfab | Silfab | | Power | 520 Wp | 590 Wp | | Efficiency | 21.90 % | 22.80 % | | Technology | N-type | N-type | ## Where they differ Ranked by how much the difference matters, not by datasheet order. | Parameter | 520 QM | 590 XM+ | Difference | | --- | --- | --- | --- | | Module efficiency | 21.90 % | 22.80 % | +0.90 pp for 590 XM+ | | Rated power | 520 Wp | 590 Wp | +70 W for 590 XM+ | | Power density | 218.8 Wp/m² | 228.6 Wp/m² | +9.8 Wp/m² for 590 XM+ | | Open-circuit voltage | 47.52 V | 52.50 V | 4.98 V apart | | Module area | 2.377 m² | 2.581 m² | 0.204 m² apart | | Weight | 26.2 kg | 28.5 kg | -2.3 kg for 520 QM | | Voltage at max power | 40.48 V | 44.79 V | 4.31 V apart | | Cell count | 132 | 144 | 12 cells apart | | Weight per kWp | 50.4 kg/kWp | 48.3 kg/kWp | -2.1 kg/kWp for 590 XM+ | | Bifacial | No | Yes | No vs Yes | | Dimensions | 2098x1133x35 mm | 2278x1133x35 mm | 2098x1133x35 mm vs 2278x1133x35 mm | ## Every compared parameter | Parameter | 520 QM | 590 XM+ | | --- | --- | --- | | Rated power | 520 Wp | 590 Wp | | Module efficiency | 21.90 % | 22.80 % | | Power density | 218.8 Wp/m² | 228.6 Wp/m² | | Open-circuit voltage | 47.52 V | 52.50 V | | Voltage at max power | 40.48 V | 44.79 V | | Short-circuit current | 13.65 A | 13.91 A | | Current at max power | 12.85 A | 13.17 A | | Temperature coefficient | -0.290 %/°C | -0.290 %/°C | | Dimensions | 2098x1133x35 mm | 2278x1133x35 mm | | Module area | 2.377 m² | 2.581 m² | | Weight | 26.2 kg | 28.5 kg | | Weight per kWp | 50.4 kg/kWp | 48.3 kg/kWp | | Product warranty | 25 yrs | 25 yrs | | Performance warranty | 30 yrs | 30 yrs | | Annual degradation | 0.35 %/yr | 0.32 %/yr | | Cell technology | N-type | N-type | | Cell type | Monocrystalline | Monocrystalline | | Cell count | 132 | 144 | | Bifacial | No | Yes | ## Thirty-year yield Each panel's own declared degradation curve, at 1,200 kWh/kWp a year Same temp coeff. for both panels (-0.290 %/°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, 520 QM:** 17,396 kWh - **Cumulative output, 590 XM+:** 19,830 kWh - **Gap:** 2,434 kWh ## Output when hot | Condition | Cell temperature | 520 QM | 590 XM+ | Retained | | --- | --- | --- | --- | --- | | Standard test conditions | 25 °C | 520 W | 590 W | 100.0% of rated power | | Cool, bright day | 40 °C | 497 W | 564 W | 95.7% of rated power | | Typical summer roof | 55 °C | 475 W | 539 W | 91.3% of rated power | | Hot roof | 70 °C | 452 W | 513 W | 87.0% of rated power | ## Against the whole database | Measure | 520 QM | 590 XM+ | Out of | Note | | --- | --- | --- | --- | --- | | Efficiency | #6,783 | #2,714 | 14,005 | 590 XM+ leads by 4,069 places | | Power density | #6,837 | #2,463 | 14,005 | 590 XM+ leads by 4,374 places | | Heat behaviour | #2,165 | #2,165 | 14,005 | Tied - the same position in the database | | Weight | #3,761 | #2,190 | 14,005 | 590 XM+ leads by 1,571 places | | Warranty | #21 | #21 | 14,005 | Tied - the same position in the database | | Overall | #4,485 | #1,554 | 14,005 | 590 XM+ leads by 2,931 places | ## Questions ### Which panel is better: Silfab SIL-520 QM or Silfab SIL-590 XM+? According to our database: **Silfab SIL-590 XM+** has higher module efficiency (**22.80%** vs **21.90%**). See the full spec comparison and 30-year energy simulation above for a complete picture. ### What is the efficiency of Silfab SIL-520 QM and Silfab SIL-590 XM+? **Silfab SIL-520 QM** has a module efficiency of **21.90%**, while **Silfab SIL-590 XM+** is **22.80%**. Higher efficiency means more electricity from the same roof area - useful when space is limited. ### What cell technology does Silfab SIL-520 QM use vs Silfab SIL-590 XM+? **Silfab SIL-520 QM** uses **N-type** cells; **Silfab SIL-590 XM+** uses **N-type**. 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 Silfab SIL-520 QM and Silfab SIL-590 XM+? **Silfab SIL-520 QM** has a **30 years** power warranty; **Silfab SIL-590 XM+** 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 Silfab SIL-520 QM and Silfab SIL-590 XM+ bifacial panels? **Silfab SIL-590 XM+** is bifacial (captures light from both faces); **Silfab SIL-520 QM** is monofacial. Bifacial panels work best on ground mounts or raised structures with a light-coloured surface underneath. ## Related comparisons - [Silfab SIL-520 QM vs Silfab SIL-580-XM+-BIFACIAL](https://comparepv.com/compare/silfab-sil-520-qm/silfab-sil-580-xm-bifacial) - 11 differences, the largest is rated power - [Silfab SIL-520 QM vs Silfab SIL-570 XM+ BIFACIAL](https://comparepv.com/compare/silfab-sil-520-qm/silfab-sil-570-xm-bifacial) - 9 differences, the largest is rated power - [Silfab SIL-520 QM vs Silfab SIL-570 XM+](https://comparepv.com/compare/silfab-sil-520-qm/silfab-sil-570-xm) - 10 differences, the largest is rated power - [Silfab SIL-520 QM vs Silfab SIL-530 XM](https://comparepv.com/compare/silfab-sil-520-qm/silfab-sil-530-xm) - 4 differences, the largest is module efficiency - [Silfab SIL-520 QM vs Silfab SIL-520 XM](https://comparepv.com/compare/silfab-sil-520-qm/silfab-sil-520-xm) - 3 differences, the largest is cell technology - [Silfab SIL-520 QM vs Silfab SIL-640 XL](https://comparepv.com/compare/silfab-sil-520-qm/silfab-sil-640-xl) - 12 differences, the largest is module efficiency --- Source: https://comparepv.com/compare/silfab-sil-520-qm/silfab-sil-590-xm 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.