--- title: "Canadian Solar CS7N-650MS vs Canadian Solar CS7N-660MS - Solar Panel Comparison | ComparePV" description: "Compare Canadian Solar CS7N-650MS vs Canadian Solar CS7N-660MS side by side: what actually differs, output when it is hot, thirty-year production, and the full specification." source: "https://comparepv.com/compare/csi-solar-co-ltd-canadian-solar-cs7n-650ms/csi-solar-co-ltd-canadian-solar-cs7n-660ms" updated: 2026-09-11 --- # Canadian Solar CS7N-650MS vs Canadian Solar CS7N-660MS 660MS leads on the differences that matter The largest is module efficiency: 0.30 pp more efficient. 16 of 19 comparable parameters are identical. ## The two panels | Attribute | A | B | | --- | --- | --- | | Panel | [Canadian Solar CS7N-650MS](https://comparepv.com/panel/csi-solar-co-ltd-canadian-solar-cs7n-650ms) | [Canadian Solar CS7N-660MS](https://comparepv.com/panel/csi-solar-co-ltd-canadian-solar-cs7n-660ms) | | Manufacturer | Canadian Solar | Canadian Solar | | Power | 650 Wp | 660 Wp | | Efficiency | 20.90 % | 21.20 % | | Technology | PERC | PERC | ## Where they differ Ranked by how much the difference matters, not by datasheet order. | Parameter | 650MS | 660MS | Difference | | --- | --- | --- | --- | | Module efficiency | 20.90 % | 21.20 % | +0.30 pp for 660MS | | Power density | 209.2 Wp/m² | 212.5 Wp/m² | +3.2 Wp/m² for 660MS | | Rated power | 650 Wp | 660 Wp | +10 W for 660MS | ## Every compared parameter | Parameter | 650MS | 660MS | | --- | --- | --- | | Rated power | 650 Wp | 660 Wp | | Module efficiency | 20.90 % | 21.20 % | | Power density | 209.2 Wp/m² | 212.5 Wp/m² | | Open-circuit voltage | 45.00 V | 45.40 V | | Voltage at max power | 37.90 V | 38.30 V | | Short-circuit current | 18.39 A | 18.47 A | | Current at max power | 17.16 A | 17.24 A | | Temperature coefficient | -0.340 %/°C | -0.340 %/°C | | Dimensions | 2384x1303x35 mm | 2384x1303x35 mm | | Module area | 3.106 m² | 3.106 m² | | Weight | 33.9 kg | 33.9 kg | | Weight per kWp | 52.2 kg/kWp | 51.4 kg/kWp | | Product warranty | 12 yrs | 12 yrs | | Performance warranty | 25 yrs | 25 yrs | | Annual degradation | 0.55 %/yr | 0.55 %/yr | | Cell technology | PERC | PERC | | Cell type | Monocrystalline | Monocrystalline | | Cell count | 132 | 132 | | Bifacial | No | No | ## 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, 650MS:** 21,066 kWh - **Cumulative output, 660MS:** 21,390 kWh - **Gap:** 324 kWh ## Output when hot | Condition | Cell temperature | 650MS | 660MS | Retained | | --- | --- | --- | --- | --- | | Standard test conditions | 25 °C | 650 W | 660 W | 100.0% of rated power | | Cool, bright day | 40 °C | 617 W | 626 W | 94.9% of rated power | | Typical summer roof | 55 °C | 584 W | 593 W | 89.8% of rated power | | Hot roof | 70 °C | 551 W | 559 W | 84.7% of rated power | ## Against the whole database | Measure | 650MS | 660MS | Out of | Note | | --- | --- | --- | --- | --- | | Efficiency | #10,072 | #9,076 | 14,005 | 660MS leads by 996 places | | Power density | #10,011 | #8,959 | 14,005 | 660MS leads by 1,052 places | | Heat behaviour | #8,778 | #8,778 | 14,005 | Tied - the same position in the database | | Weight | #5,614 | #4,737 | 14,005 | 660MS leads by 877 places | | Warranty | #9,798 | #9,798 | 14,005 | Tied - the same position in the database | | Overall | #4,886 | #4,203 | 14,005 | 660MS leads by 683 places | ## Questions ### Which panel is better: Canadian Solar CS7N-650MS or Canadian Solar CS7N-660MS? According to our database: **Canadian Solar CS7N-660MS** has higher module efficiency (**21.20%** vs **20.90%**). See the full spec comparison and 30-year energy simulation above for a complete picture. ### What is the efficiency of Canadian Solar CS7N-650MS and Canadian Solar CS7N-660MS? **Canadian Solar CS7N-650MS** has a module efficiency of **20.90%**, while **Canadian Solar CS7N-660MS** is **21.20%**. Higher efficiency means more electricity from the same roof area - useful when space is limited. ### What cell technology does Canadian Solar CS7N-650MS use vs Canadian Solar CS7N-660MS? **Canadian Solar CS7N-650MS** uses **PERC** cells; **Canadian Solar CS7N-660MS** 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 Canadian Solar CS7N-650MS and Canadian Solar CS7N-660MS? **Canadian Solar CS7N-650MS** has a **25 years** power warranty; **Canadian Solar CS7N-660MS** has a **25 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. ## Related comparisons - [Canadian Solar CS7N-650MS vs Canadian Solar CS7N-675MS](https://comparepv.com/compare/csi-solar-co-ltd-canadian-solar-cs7n-650ms/csi-solar-co-ltd-canadian-solar-cs7n-675ms) - 5 differences, the largest is module efficiency - [Canadian Solar CS7N-650MS vs Canadian Solar CS7N-670MS](https://comparepv.com/compare/csi-solar-co-ltd-canadian-solar-cs7n-650ms/csi-solar-co-ltd-canadian-solar-cs7n-670ms) - 3 differences, the largest is module efficiency - [Canadian Solar CS7N-650MS vs Canadian Solar CS7N-665MS](https://comparepv.com/compare/csi-solar-co-ltd-canadian-solar-cs7n-650ms/csi-solar-co-ltd-canadian-solar-cs7n-665ms) - 3 differences, the largest is module efficiency - [Canadian Solar CS7N-650MS vs Canadian Solar CS7N-655MS](https://comparepv.com/compare/csi-solar-co-ltd-canadian-solar-cs7n-650ms/csi-solar-co-ltd-canadian-solar-cs7n-655ms) - One difference: module efficiency - [Canadian Solar CS7N-650MS vs Canadian Solar CS7N-645MS](https://comparepv.com/compare/csi-solar-co-ltd-canadian-solar-cs7n-650ms/csi-solar-co-ltd-canadian-solar-cs7n-645ms) - The same specification on paper - [Canadian Solar CS7N-650MS vs Canadian Solar CS7L-615MS](https://comparepv.com/compare/csi-solar-co-ltd-canadian-solar-cs7n-650ms/csi-solar-co-ltd-canadian-solar-cs7l-615ms) - 9 differences, the largest is module efficiency --- Source: https://comparepv.com/compare/csi-solar-co-ltd-canadian-solar-cs7n-650ms/csi-solar-co-ltd-canadian-solar-cs7n-660ms 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.