--- title: "JA Solar JAM66D46-735/LB vs JA Solar JAT54S41-475/LR - Solar Panel Comparison | ComparePV" description: "Compare JA Solar JAM66D46-735/LB vs JA Solar JAT54S41-475/LR side by side: what actually differs, output when it is hot, thirty-year production, and the full specification." source: "https://comparepv.com/compare/ja-solar-jam66d46-735-lb/ja-solar-jat54s41-475-lr" updated: 2026-09-11 --- # JA Solar JAM66D46-735/LB vs JA Solar JAT54S41-475/LR JAT54S41-475/LR leads on the differences that matter The largest is rated power: 260 W more power. 6 of 19 comparable parameters are identical. ## The two panels | Attribute | A | B | | --- | --- | --- | | Panel | [JA Solar JAM66D46-735/LB](https://comparepv.com/panel/ja-solar-jam66d46-735-lb) | [JA Solar JAT54S41-475/LR](https://comparepv.com/panel/ja-solar-jat54s41-475-lr) | | Manufacturer | JA Solar | JA Solar | | Power | 735 Wp | 475 Wp | | Efficiency | 23.70 % | 23.80 % | | Technology | TOPCon | TOPCon | ## Where they differ Ranked by how much the difference matters, not by datasheet order. | Parameter | JAM66D46-735/LB | JAT54S41-475/LR | Difference | | --- | --- | --- | --- | | Rated power | 735 Wp | 475 Wp | +260 W for JAM66D46-735/LB | | Temperature coefficient | -0.290 %/°C | -0.260 %/°C | +0.030 %/°C for JAT54S41-475/LR | | Weight | 38.2 kg | 19.3 kg | -18.9 kg for JAT54S41-475/LR | | Weight per kWp | 52.0 kg/kWp | 40.6 kg/kWp | -11.3 kg/kWp for JAT54S41-475/LR | | Product warranty | 12 yrs | 25 yrs | +13 yrs for JAT54S41-475/LR | | Open-circuit voltage | 49.60 V | 41.03 V | 8.57 V apart | | Short-circuit current | 18.70 A | 14.90 A | 3.80 A apart | | Module area | 3.106 m² | 1.998 m² | 1.108 m² apart | | Voltage at max power | 41.77 V | 34.87 V | 6.90 V apart | | Current at max power | 17.60 A | 13.63 A | 3.97 A apart | | Cell count | 132 | 108 | 24 cells apart | | Bifacial | Yes | No | Yes vs No | | Dimensions | 2384x1303x33 mm | 1762x1134x30 mm | 2384x1303x33 mm vs 1762x1134x30 mm | ## Every compared parameter | Parameter | JAM66D46-735/LB | JAT54S41-475/LR | | --- | --- | --- | | Rated power | 735 Wp | 475 Wp | | Module efficiency | 23.70 % | 23.80 % | | Power density | 236.6 Wp/m² | 237.7 Wp/m² | | Open-circuit voltage | 49.60 V | 41.03 V | | Voltage at max power | 41.77 V | 34.87 V | | Short-circuit current | 18.70 A | 14.90 A | | Current at max power | 17.60 A | 13.63 A | | Temperature coefficient | -0.290 %/°C | -0.260 %/°C | | Dimensions | 2384x1303x33 mm | 1762x1134x30 mm | | Module area | 3.106 m² | 1.998 m² | | Weight | 38.2 kg | 19.3 kg | | Weight per kWp | 52.0 kg/kWp | 40.6 kg/kWp | | Product warranty | 12 yrs | 25 yrs | | Performance warranty | 30 yrs | 30 yrs | | Annual degradation | 0.40 %/yr | 0.40 %/yr | | Cell technology | TOPCon | TOPCon | | Cell type | Monocrystalline | Monocrystalline | | Cell count | 132 | 108 | | Bifacial | Yes | No | ## Thirty-year yield Each panel's own declared degradation curve, at 1,200 kWh/kWp a year - **Cumulative output, JAM66D46-735/LB:** 24,661 kWh - **Cumulative output, JAT54S41-475/LR:** 15,937 kWh - **Gap:** 8,724 kWh ## Output when hot | Condition | Cell temperature | JAM66D46-735/LB | JAT54S41-475/LR | Retained | | --- | --- | --- | --- | --- | | Standard test conditions | 25 °C | 735 W | 475 W | 100.0% of rated power | | Cool, bright day | 40 °C | 703 W | 456 W | 95.7% of rated power | | Typical summer roof | 55 °C | 671 W | 438 W | 91.3% of rated power | | Hot roof | 70 °C | 639 W | 419 W | 87.0% of rated power | ## Against the whole database | Measure | JAM66D46-735/LB | JAT54S41-475/LR | Out of | Note | | --- | --- | --- | --- | --- | | Efficiency | #517 | #433 | 14,005 | JAT54S41-475/LR leads by 84 places | | Power density | #582 | #467 | 14,005 | JAT54S41-475/LR leads by 115 places | | Heat behaviour | #2,165 | #511 | 14,005 | JAT54S41-475/LR leads by 1,654 places | | Weight | #5,413 | #165 | 14,005 | JAT54S41-475/LR leads by 5,248 places | | Warranty | #21 | #21 | 14,005 | Tied - the same position in the database | | Overall | #233 | #3,637 | 14,005 | JAM66D46-735/LB leads by 3,404 places | ## Questions ### Which panel is better: JA Solar JAM66D46-735/LB or JA Solar JAT54S41-475/LR? According to our database: **JA Solar JAT54S41-475/LR** has higher module efficiency (**23.80%** vs **23.70%**); **JA Solar JAT54S41-475/LR** tolerates heat better (temp coeff **-0.260%/°C** vs **-0.290%/°C**). See the full spec comparison and 30-year energy simulation above for a complete picture. ### What is the efficiency of JA Solar JAM66D46-735/LB and JA Solar JAT54S41-475/LR? **JA Solar JAM66D46-735/LB** has a module efficiency of **23.70%**, while **JA Solar JAT54S41-475/LR** is **23.80%**. Higher efficiency means more electricity from the same roof area - useful when space is limited. ### What cell technology does JA Solar JAM66D46-735/LB use vs JA Solar JAT54S41-475/LR? **JA Solar JAM66D46-735/LB** uses **TOPCon** cells; **JA Solar JAT54S41-475/LR** uses **TOPCon**. 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 JA Solar JAM66D46-735/LB and JA Solar JAT54S41-475/LR? **JA Solar JAM66D46-735/LB** has a **30 years** power warranty; **JA Solar JAT54S41-475/LR** 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 JA Solar JAM66D46-735/LB and JA Solar JAT54S41-475/LR bifacial panels? **JA Solar JAM66D46-735/LB** is bifacial (captures light from both faces); **JA Solar JAT54S41-475/LR** is monofacial. Bifacial panels work best on ground mounts or raised structures with a light-coloured surface underneath. ## Related comparisons - [JA Solar JAM66D46-735/LB vs JA Solar JAM66D46-740/LB](https://comparepv.com/compare/ja-solar-jam66d46-735-lb/ja-solar-jam66d46-740-lb) - The same specification on paper - [JA Solar JAM66D46-735/LB vs JA Solar JAM66D46-730/LB](https://comparepv.com/compare/ja-solar-jam66d46-735-lb/ja-solar-jam66d46-730-lb) - One difference: module efficiency - [JA Solar JAM66D46-735/LB vs JA Solar JAM66D46-725/LB](https://comparepv.com/compare/ja-solar-jam66d46-735-lb/ja-solar-jam66d46-725-lb) - 3 differences, the largest is module efficiency - [JA Solar JAM66D46-735/LB vs JA Solar JAM66D46-720/LB](https://comparepv.com/compare/ja-solar-jam66d46-735-lb/ja-solar-jam66d46-720-lb) - 3 differences, the largest is module efficiency - [JA Solar JAM66D46-735/LB vs JA Solar JAM66D46-715/LB](https://comparepv.com/compare/ja-solar-jam66d46-735-lb/ja-solar-jam66d46-715-lb) - 3 differences, the largest is module efficiency - [JA Solar JAM66D46-735/LB vs JA Solar JAM66D46-710/LB](https://comparepv.com/compare/ja-solar-jam66d46-735-lb/ja-solar-jam66d46-710-lb) - 5 differences, the largest is module efficiency --- Source: https://comparepv.com/compare/ja-solar-jam66d46-735-lb/ja-solar-jat54s41-475-lr 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.