--- title: "JA Solar JAM66D45-650/LB Solar Panel: Specs & Datasheet | ComparePV" description: "JA Solar JAM66D45-650/LB solar panel. Specs: 24.10% efficiency, Monocrystalline cells, dimensions, warranty and temperature coefficient." source: "https://comparepv.com/panel/ja-solar-jam66d45-650-lb" image: "https://comparepv.com/og/panel/ja-solar-jam66d45-650-lb.png" updated: 2026-09-11 --- # JA Solar JAM66D45-650/LB Efficiency leader, no clear weak spot 254 panels in the segment TOPCon 650-700 W ## Identity - **Manufacturer:** JA Solar - **Model:** JAM66D45-650/LB - **Series:** JAM66D45 LB - **Rated power:** 650 W - **Cell technology:** TOPCon - **Bifacial:** yes ## How it compares Compared against segment TOPCon 650-700 W (254 panels). | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Power (Wp) | 650 W | 665 W | Weak - bottom 13% | | | Module efficiency | 24.10% | 22.40% | Strong - top 17% | 241 | | Power density | 240.6 | 223.7 | Strong - top 20% | 255 | | Temperature coefficient | -0.290 | -0.290 | Typical | 2,220 | | Weight (kg) | 33.1 kg | 34.6 kg | Typical | | | Performance warranty | 30 yrs | 30 yrs | Typical | 21 | ### Full peer table | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Module efficiency | 24.10% | 22.40% | Strong - top 17% | 241 | | Power density | 240.6 | 223.7 | Strong - top 20% | 255 | | Temperature coefficient | -0.290 | -0.290 | Typical | 2,220 | | Weight per kWp | 50.9 | 53.1 | Typical | 4,322 | | Performance warranty | 30 yrs | 30 yrs | Typical | 21 | ### Strengths - **24.10% module efficiency** - Top 17% of the TOPCon 650-700 W segment, against a median of 22.40%. - **240.6 watts per square metre** - Top 20% of the TOPCon 650-700 W segment, against a median of 223.7. - **Best for:** Commercial, utility-scale and shaded-installations. ## Specification ### Electrical - **Rated power (Pmax):** 650 W - **Efficiency:** 24.10 % - **Voltage at Pmax (Vmp):** 41.67 V - **Current at Pmax (Imp):** 16.30 A - **Open-circuit voltage (Voc):** 49.97 V - **Short-circuit current (Isc):** 17.99 A - **Max system voltage:** 1500 V ### Temperature - **Temperature coefficient of Pmax:** -0.290 %/degC - **Temperature coefficient of Voc:** -0.250 %/degC - **Temperature coefficient of Isc:** 0.045 %/degC - **NOCT:** 45 degC ### Cell and construction - **Cell type:** Monocrystalline - **Cell technology:** TOPCon - **Cell count:** 132 - **Bifacial:** yes ### Physical - **Length:** 2382 mm - **Width:** 1134 mm - **Thickness:** 30 mm - **Weight:** 33.1 kg - **Area:** 2.70 m2 - **Power density:** 240.6 Wp/m2 ### Warranty and degradation - **Product warranty:** 12 years - **Performance warranty:** 30 years - **Output guaranteed at end of warranty:** 88.4 % - **First-year degradation:** 1.00 % - **Annual degradation:** 0.40 % - **Output after 30 years:** 568 W ## Rank in the whole catalogue | Measure | Position | | --- | --- | | Efficiency | 241 of 14129 | | Power density | 255 of 14129 | | Temperature coefficient | 2220 of 14129 | | Weight | 4322 of 14129 | | Warranty | 21 of 14129 | ## Pros - **Up to 24.1% efficiency - peer-group leader** - The JAM66D45 LB series reaches a module efficiency of up to 24.1%, outperforming all direct peer comparables: Astronergy ASTRO N5 (23.3%), BYD AURO N (23.25%), and Jinko Solar Tiger Neo 66HL4M-BDX (24.06%). The margin over the peer-group median is approximately 0.7-0.85 percentage points, directly reducing area requirements and BoS cost per kWp. - **N-type TOPCon - zero LID, better Tcoeff** - N-type TOPCon cells eliminate Light-Induced Degradation (LID) inherent to P-type PERC. The power temperature coefficient is approximately -0.29%/°C (per ENF/manuals.plus data), versus -0.34 to -0.35%/°C for standard PERC - translating into measurably higher energy yield on hot summer days, especially relevant for C&I rooftop and utility-scale deployments. - **Bifacial dual-glass - 5-15% additional yield** - A bifaciality factor of ~85% enables 5-15% additional energy harvest from albedo, depending on ground surface (concrete, light gravel). The dual-glass construction (30 mm frame) raises mechanical resistance to 5,400 Pa (snow load) and 2,400 Pa (wind), while the IP68-rated junction box guards against PID-driven humidity degradation across the full 30-year operating life. - **30-year linear power warranty** - JA Solar guarantees retention of >87% of rated power after 30 years under a linear degradation schedule. This is among the longest warranty horizons available in the bifacial dual-glass 650 W segment and directly improves LCOE for long-duration projects - particularly relevant for non-recourse financed utility-scale PV farms. - **JA Solar Tier 1 - #1 Wood Mackenzie H1 2025** - JA Solar is listed on the BNEF Tier 1 bankable manufacturers list and ranked first in the Wood Mackenzie Global Solar Module Manufacturer Ranking for H1 2025 with an overall score of 91.7/100. This translates directly into stronger project bankability, lower residual risk for institutional investors, and easier access to non-recourse project financing. ## Cons - **~33 kg weight - roof structure requirements** - The dual-glass module weighs approximately 33.1 kg versus ~26-28 kg for comparable single-glass modules of similar wattage. Retrofit installations on existing C&I rooftops require structural load assessments on a case-by-case basis, adding engineering costs and potentially limiting applicability on buildings with lightweight steel purlins. ## About this series JA Solar JAM66D45 LB series modules are designed for installations where maximum energy yield and long-term peace of mind are key considerations - on commercial and industrial rooftops as well as in large PV farms. The use of **N-type TOPCon cells** helps minimize power losses over time and improves performance in demanding conditions, such as high temperatures or lower irradiance. The **bifacial design** allows for utilizing reflected light from the backside, effectively increasing energy production without expanding the installation. Additionally, **double glazing** enhances resistance to atmospheric factors and mechanical stress, which is crucial for investments with a long horizon. From a total cost perspective, this product stands out due to its approach focused on low energy cost in the lifecycle and predictable performance. It is an excellent choice for investors who wish to combine **high reliability proven in tests** with modern technology and the potential for additional gain from the rear side of the module. ## Notable figures - Efficiency of 24.1% is 1.7pp above the \*\*TOPCon 650-700W\*\* median (22.4%) - At 240.6 W/m² power density, this panel generates 16.9 W/m² more per unit area than \*\*TOPCon 650-700W\*\* median (223.7 W/m²) - At -0.29%/°C, hot weather performance is typical for \*\*TOPCon 650-700W\*\* panels - Weight of 33.1 kg (1.5 kg below \*\*TOPCon 650-700W\*\* median of 34.6 kg) allows easier transport and roof mounting - Bifacial design (80% factor) captures reflected light - adds 4-12% yield on ground-mount or white roof ## Questions ### What warranty does the JA Solar JAM66D45 LB series come with? The JAM66D45 LB series comes with a 12-year product warranty covering materials and workmanship, plus a 30-year linear power output warranty. After 30 years, the module is guaranteed to retain approximately 83% of its nominal output. This is one of the longer warranty standards available on the market, especially relevant for commercial rooftop and utility-scale investments with long payback horizons. ### What is TOPCon technology and why does the JAM66D45 LB series use it? TOPCon (Tunnel Oxide Passivated Contact) is an N-type cell technology that uses a thin tunnel oxide layer to minimize carrier recombination at the cell contacts. In practice, this delivers higher module efficiency (up to ~23.3%), a lower temperature coefficient (~-0.29%/°C), and slower power degradation over time compared to PERC cells. The JAM66D45 LB series uses TOPCon specifically to lower the lifetime cost of energy (LCOE) from the installation. ### How do the bifacial JAM66D45 LB panels increase energy production, and when does it make sense? The JAM66D45 LB modules feature up to 80% bifaciality, meaning the rear side captures light reflected from the surface beneath the array. With a high-albedo ground cover - light gravel, concrete, or snow - this can add roughly 5-15% to energy output compared to a monofacial module of the same nominal power. The actual gain depends on site albedo, tilt angle, and mounting height above ground. ### Is the JAM66D45 LB series suitable for large-scale utility PV farms? Yes, utility-scale installations are one of the primary use cases for this series. The modules support a 1500 V DC system voltage, simplifying string design and reducing BoS costs. Front snow load resistance of 5,400 Pa and rear wind load of 2,400 Pa make them suitable for demanding locations. The double-glass construction and N-type TOPCon technology ensure predictable production throughout the full investment lifecycle. ### How does the JAM66D45 LB series perform in high-temperature conditions? The power temperature coefficient for the JAM66D45 LB is approximately -0.29%/°C, meaning the module loses about 2.9% of its rated output for every 10°C rise above 25°C. This outperforms most PERC modules, which typically show around -0.35%/°C. The N-type TOPCon technology helps maintain higher production on hot days - particularly important on dark industrial rooftops with limited airflow. ### What are the dimensions and weight of the JAM66D45 LB module, and is it compatible with standard racking systems? The JAM66D45 LB module measures 2382 × 1134 × 30 mm and weighs approximately 33.1 kg. This is a commercial and utility-scale format - its size and weight require a properly engineered racking system and appropriate lifting equipment during installation. It is not a standard fit for small residential rooftop systems on typical pitched roofs. ## Datasheet [Manufacturer datasheet (PDF)](https://comparepv.com/datasheets/cb4feec76c9f3a-965360decfa0.pdf) ## Alternatives | Panel | Power | How it differs | | --- | --- | --- | | [AIKO AIKO-A650-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a650-mae72mw) | 650 W | Cooler, lighter, +1.1 pp | | [AIKO AIKO-A680-MDE72Mw](https://comparepv.com/panel/aiko-aiko-a680-mde72mw) | 680 W | +30 W, lighter, +1.1 pp | | [AIKO AIKO-A675-MDE72Mw](https://comparepv.com/panel/aiko-aiko-a675-mde72mw) | 675 W | Cooler, lighter, +0.9 pp | | [AIKO AIKO-A645-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a645-mae72mw) | 645 W | Cooler, lighter, +0.9 pp | | [AIKO AIKO-A700-MAE78Dw](https://comparepv.com/panel/aiko-aiko-a700-mae78dw) | 700 W | +50 W, cooler, +0.9 pp | | [WINAICO WST-675BKX72-A2](https://comparepv.com/panel/winaico-wst-675bkx72-a2) | 675 W | +25 W, cooler, +0.9 pp | | [AIKO AIKO-A695-MAE78Dw](https://comparepv.com/panel/aiko-aiko-a695-mae78dw) | 695 W | +45 W, cooler, +0.8 pp | | [AIKO AIKO-G670-MCH72Mw](https://comparepv.com/panel/aiko-aiko-g670-mch72mw) | 670 W | Cooler, lighter, +0.7 pp | | [JA Solar JAM66D45-605/LB](https://comparepv.com/panel/ja-solar-jam66d45-605-lb) | 605 W | -45 W, -1.7 pp | | [JA Solar JAM66D45-610/LB](https://comparepv.com/panel/ja-solar-jam66d45-610-lb) | 610 W | -40 W, -1.5 pp | | [JA Solar JAM66D45-615/LB](https://comparepv.com/panel/ja-solar-jam66d45-615-lb) | 615 W | -35 W, -1.3 pp | | [JA Solar JAM66D45-620/LB](https://comparepv.com/panel/ja-solar-jam66d45-620-lb) | 620 W | -30 W, -1.1 pp | | [JA Solar JAM66D45-625/LB](https://comparepv.com/panel/ja-solar-jam66d45-625-lb) | 625 W | -25 W, -1.0 pp | | [JA Solar JAM66D45-630/LB](https://comparepv.com/panel/ja-solar-jam66d45-630-lb) | 630 W | -20 W, -0.8 pp | | [JA Solar JAM66D45-635/LB](https://comparepv.com/panel/ja-solar-jam66d45-635-lb) | 635 W | -15 W, -0.6 pp | | [Longi Solar LR7-72HVHF-670M](https://comparepv.com/panel/longi-lr7-72hvhf-670m) | 670 W | Cooler, lighter, +0.7 pp | --- Source: https://comparepv.com/panel/ja-solar-jam66d45-650-lb Not in this file, on the page: a thirty-year output simulator, a bifacial gain calculator and alternatives filtered by how closely they match these dimensions.