--- title: "JA Solar JAM72D42-645/LB 645W Solar Panel - Specs & Review | ComparePV" description: "JA Solar JAM72D42-645/LB 645W solar panel: 1 shop offer from 442.79 zł. Specs: 23.10% efficiency, Monocrystalline cells." source: "https://comparepv.com/panel/ja-solar-jam72d42-645-lb" updated: 2026-09-29 --- # JA Solar JAM72D42-645/LB Solid all-round for its segment 1,086 panels in the segment TOPCon 600-650 W ## Identity - **Manufacturer:** JA Solar - **Model:** JAM72D42-645/LB - **Series:** JAM72D42 LB - **Rated power:** 645 W - **Cell technology:** TOPCon - **Bifacial:** yes ## Price offers Prices are the figure each shop printed, on that shop's side of VAT. | Shop | Market | Price | Per kWp | Availability | Last read | | --- | --- | --- | --- | --- | --- | | [Megawat Elektrohurt](https://comparepv.com/go/1820) | Poland | 442.79 zł incl. VAT | 686.49 zł/kWp | In stock | Last read 29 Sep 03:26 | ## How it compares Compared against segment TOPCon 600-650 W (1086 panels). | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Power (Wp) | 645 W | 620 W | Strong - top 3% | | | Module efficiency | 23.10% | 22.80% | Typical | 1,570 | | Power density | 230.7 | 227.7 | Typical | 1,654 | | Temperature coefficient | -0.290 | -0.290 | Typical | 2,165 | | Weight (kg) | 34.6 kg | 32.7 kg | Typical | | | Performance warranty | 30 yrs | 30 yrs | Typical | 21 | ### Full peer table | Measure | This panel | Segment median | Standing | Rank | | --- | --- | --- | --- | --- | | Module efficiency | 23.10% | 22.80% | Typical | 1,570 | | Power density | 230.7 | 227.7 | Typical | 1,654 | | Temperature coefficient | -0.290 | -0.290 | Typical | 2,165 | | Weight per kWp | 53.6 | 53.1 | Typical | 7,650 | | Performance warranty | 30 yrs | 30 yrs | Typical | 21 | - **Best for:** Utility-scale, commercial and shaded-installations. ## Specification ### Electrical - **Rated power (Pmax):** 645 W - **Efficiency:** 23.10 % - **Voltage at Pmax (Vmp):** 44.49 V - **Current at Pmax (Imp):** 14.50 A - **Open-circuit voltage (Voc):** 53.07 V - **Short-circuit current (Isc):** 15.36 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:** 144 - **Bifacial:** yes - **Bifacial gain:** 10.00 ### Physical - **Length:** 2465 mm - **Width:** 1134 mm - **Thickness:** 30 mm - **Weight:** 34.6 kg - **Area:** 2.80 m2 - **Power density:** 230.7 Wp/m2 ### Warranty and degradation - **Product warranty:** 12 years - **Performance warranty:** 30 years - **Output guaranteed at end of warranty:** 87.4 % - **First-year degradation:** 1.00 % - **Annual degradation:** 0.40 % - **Output after 30 years:** 564 W ## Rank in the whole catalogue | Measure | Position | | --- | --- | | Efficiency | 1570 of 14005 | | Power density | 1654 of 14005 | | Temperature coefficient | 2165 of 14005 | | Weight | 7650 of 14005 | | Warranty | 21 of 14005 | ## Pros - **N-type TOPCon – low degradation rate** - N-type TOPCon cell technology delivers an annual degradation rate of 0.4%/year (1% in year 1), guaranteeing ≥87.4% of nameplate power after 30 years. Conventional PERC modules typically degrade at 0.45–0.55%/year, meaning the JAM72D42 LB retains 1–3 pp more power over the same period, translating directly into higher lifetime energy yield and a lower LCOE. - **Bifacial double-glass construction** - An 80% (±10%) bifaciality factor enables energy harvesting from ground-reflected irradiance, yielding an additional 5–15% annual output on utility-scale ground-mount sites with light-colored substrates (gravel, snow). The glass-glass encapsulation eliminates the EVA backsheet, improving moisture resistance and extending mechanical service life compared to glass-foil modules. - **30-year linear power warranty** - JA Solar guarantees a 30-year linear power warranty with a ≥87.4% floor at year 30, backed by a 12-year product workmanship warranty — consistent with other Tier-1 bifacial TOPCon peers (Astronergy ASTRO N5, BYD AURO N) and exceeding the 25-year standard common in legacy PERC product lines. The linear structure minimizes uncertainty in long-term yield modeling for project finance. - **BNEF Tier-1 bankability** - JA Solar (founded 2005, China) maintains BNEF Tier-1 status as of Q1 2026, satisfying the standard non-recourse project finance requirement of modules sourced from a bankable manufacturer. This designation eliminates technology-risk flags during lender due diligence for utility-scale PV projects and supports insurance underwriting. - **High power density – 625–650 Wp, 6 variants** - The 625–650 Wp power range across 6 variants enables flexible string and MPPT design optimization for utility inverters. High per-module power reduces the total panel count on a given site, lowering BoS costs — including cabling, racking, and installation labor — on a per-MWp basis. ## Cons - **Lower efficiency vs. Jinko Tiger Neo** - The series peaks at 23.3% module efficiency, while the directly comparable Jinko Solar Tiger Neo 66HL4M-BDX (625–650 W, bifacial dual-glass) reaches 24.06% — a gap of approximately 0.76 pp. On area-constrained utility sites with a fixed footprint, this difference may require roughly 3–4% more JAM72D42 LB modules to achieve the same installed capacity, partially offsetting BoS savings. ## About this series The JA Solar JAM72D42 LB series are modules engineered for PV farms and large-scale installations, where maximizing yield from every string row is critical. Their unique combination of **N-type TOPCon cells** with a **double-glass (glass-glass) construction** and **bifaciality** ensures stable performance even in challenging field conditions and weather, while additionally harnessing reflected ground light. This solution benefits investors seeking to mitigate operational risks common in large-scale projects: lower long-term degradation facilitates maintaining planned production, and the rigid glass-glass structure enhances resistance to long-term stress. The application of modern cell architecture (including microcell technology) improves resilience against partial shading losses and boosts the reliability of string performance. JAM72D42 LB modules are most often selected by farm developers, EPC contractors, and the industrial sector-where **high power density** and a genuinely lower energy cost throughout the installation's lifecycle provide a competitive advantage. ## Notable figures - Efficiency of 23.1% matches the \*\*TOPCon 600-650W\*\* median - 230.7 W/m² power density - 3.0 W/m² more than \*\*TOPCon 600-650W\*\* median (227.7 W/m²), more power per roof area - At -0.29%/°C, hot weather performance is typical for \*\*TOPCon 600-650W\*\* panels - At 34.6 kg (1.9 kg above \*\*TOPCon 600-650W\*\* median of 32.7 kg), requires checking roof load capacity - Bifaciality factor of 80% can add 4-12% extra yield with reflective mounting surface ## Questions ### What warranty does the JA Solar JAM72D42 LB come with? The JAM72D42 LB series carries a 12-year product warranty and a 30-year linear power output warranty. After 30 years of operation, JA Solar guarantees at least 87.4% of nominal power, with an annual degradation rate of only 0.4%. This allows developers and EPC contractors to model energy production with high confidence across the full project lifetime. ### What is the real-world bifacial gain for JAM72D42 LB modules? The JAM72D42 LB has a bifaciality factor of 80% (±10%), meaning the rear side can produce up to 80% of the power the front side generates under the same irradiance. In practice, with high-albedo ground surfaces such as concrete, light gravel, or snow, the bifacial gain typically ranges from 5% to 15% above STC nameplate power. The gain is maximized with tracker or elevated fixed-tilt mounting that allows light to reach the rear side. ### How does N-type TOPCon technology in the JAM72D42 LB compare to standard PERC cells? N-type TOPCon cells in the JAM72D42 LB deliver a lower annual degradation rate (0.4% vs. approximately 0.55% for PERC) and are virtually free of light-induced degradation (LID/LeTID). This results in higher module efficiency (up to 22.9%), better low-irradiance performance, and a lower LCOE over the project lifetime compared to equivalent PERC-based modules. ### Can JAM72D42 LB panels withstand heavy snow loads and strong winds? Yes. The double glass construction provides a front mechanical load rating of 5,400 Pa and 2,400 Pa on the rear — sufficient for heavy snow accumulation and high wind loads. The glass-glass build also seals cells from moisture ingress far more effectively than glass-backsheet alternatives, which is critical for multi-decade reliability of utility-scale plants operating in demanding climates. ### What types of installations is the JA Solar JAM72D42 LB designed for? The JAM72D42 LB is engineered for utility-scale solar farms and large commercial or industrial projects. At 2,465 × 1,134 mm and approximately 34.6 kg, with power outputs up to 650 Wp, it is not suited for residential rooftop installations. It requires professional mounting structures and handling equipment, making it the preferred choice of solar developers, EPC contractors, and industrial asset owners. ### Is the JAM72D42 LB compatible with 1,500 V inverter systems? Yes, the JAM72D42 LB is rated for a 1,500 V DC system voltage, the current utility-scale standard. Operating at 1,500 V allows longer string configurations per MPPT input, reducing balance-of-system (BoS) costs through lower cabling losses and fewer combiner boxes per megawatt installed — a key advantage for large-scale project economics. ## Datasheet [Manufacturer datasheet (PDF)](https://comparepv.com/datasheets/b1d39cfaeb1d0f5-2185a2252d29.pdf) ## Alternatives | Panel | Power | How it differs | | --- | --- | --- | | [AIKO AIKO-A650-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a650-mae72mw) | 650 W | Cooler, lighter, +2.1 pp | | [AIKO AIKO-A680-MDE72Mw](https://comparepv.com/panel/aiko-aiko-a680-mde72mw) | 680 W | +35 W, lighter, +2.1 pp | | [AIKO AIKO-A675-MDE72Mw](https://comparepv.com/panel/aiko-aiko-a675-mde72mw) | 675 W | +30 W, lighter, +1.9 pp | | [AIKO AIKO-A645-MAE72Mw](https://comparepv.com/panel/aiko-aiko-a645-mae72mw) | 645 W | Cooler, lighter, +1.9 pp | | [AIKO AIKO-A695-MAE78Dw](https://comparepv.com/panel/aiko-aiko-a695-mae78dw) | 695 W | +50 W, cooler, +1.8 pp | | [AIKO AIKO-G670-MCH72Mw](https://comparepv.com/panel/aiko-aiko-g670-mch72mw) | 670 W | Cooler, lighter, +1.7 pp | | [Longi Solar LR7-72HVHF-670M](https://comparepv.com/panel/longi-lr7-72hvhf-670m) | 670 W | Cooler, lighter, +1.7 pp | | [JA Solar JAM78S30-580/MR](https://comparepv.com/panel/ja-solar-jam78s30-580-mr) | 580 W | -65 W, hotter, -2.4 pp | | [JA Solar JAM78S30-585/MR](https://comparepv.com/panel/ja-solar-jam78s30-585-mr) | 585 W | -60 W, hotter, -2.2 pp | | [JA Solar JAM78S30-590/MR](https://comparepv.com/panel/ja-solar-jam78s30-590-mr) | 590 W | -55 W, hotter, -2.0 pp | | [JA Solar JAM78S30-595/MR](https://comparepv.com/panel/ja-solar-jam78s30-595-mr) | 595 W | -50 W, hotter, -1.8 pp | | [JA Solar JAM78S30-600/MR](https://comparepv.com/panel/ja-solar-jam78s30-600-mr) | 600 W | Hotter, -1.6 pp, -5 yr warranty | | [AIKO AIKO-A700-MAE78Dw](https://comparepv.com/panel/aiko-aiko-a700-mae78dw) | 700 W | +55 W, cooler, +1.9 pp | | [Jinko Solar JKM650-670N-66QL6-BDV (670W class)](https://comparepv.com/panel/jinko-solar-jkm650-670n-66ql6-bdv-670w-class) | 670 W | +25 W, cooler, +1.7 pp | --- Source: https://comparepv.com/panel/ja-solar-jam72d42-645-lb Not in this file, on the page: the I-V and temperature curves lifted from the manufacturer's datasheet, a thirty-year output simulator, a bifacial gain calculator and alternatives filtered by how closely they match these dimensions.