Middle of its segment, modest efficiency
JA Solar JAM78S30 580-605/MR series modules are designed for installations where high power per unit and reliable operation in long strings are crucial. The use of large monocrystalline cells in PERC technology helps better utilize light under real working conditions, while the monofacial glass-backsheet construction remains a practical choice where predictable yield and simple integration with standard farm infrastructure are prioritized.
A key feature of this series is its approach focused on reducing the entire system's costs - fewer modules to achieve the required power, fewer connections, and faster installation, facilitating budget and schedule control. The modules feature an IP68 connector box, supporting reliability in rain, snow, and dusty conditions. This is an excellent choice for PV farms, large industrial rooftops, and commercial projects, where logistics, serviceability, low degradation over time, and stable energy yield are important.
Ranking
Signals from the data
Utility-scale, commercial and shaded-installations.
Tight roof space, roofs where every square metre has to count and owners who want a long output guarantee.
Bottom 8% of the PERC 550-600 W segment, against a median of 21.29%. Ranked 10,764th in the whole database.
Bottom 10% of the PERC 550-600 W segment, against a median of 212.9. Ranked 10,596th in the whole database.
Bottom 24% of the PERC 550-600 W segment, against a median of 27 yrs.
JA Solar appears on the BNEF Tier 1 Q2 2026 list, confirming bankability for project finance. With operations since 2005 and annual shipments exceeding 100 GWp, the company presents minimal counterparty risk for utility-scale PV asset owners.
The 580–605 Wp range delivers the required system capacity with fewer modules, fewer string connections, and reduced installation time. For a 1 MWp plant, this series requires approximately 15–17% fewer modules compared to typical 500 Wp modules from 2019–2020, directly reducing BoS and logistics costs.
JA Solar guarantees annual degradation not exceeding 0.55% and a minimum of 84.8% of rated power after 25 years, backed by a 12-year product warranty. This is a competitive commitment for PERC-class modules.
The IP68 junction box rating ensures complete dust-tight protection and resistance to sustained water immersion — critical for ground-mount installations exposed to heavy rainfall, flooding, and dust accumulation, reducing the risk of field electrical failures.
The M10 (182 mm) cell format with 11-busbar and half-cut architecture reduces resistive current losses and improves performance under partial shading. The 6×26 cell layout (156 cells) in a 2465×1134 mm frame sustains module efficiency up to 21.6% within the PERC class.
Per manufacturer data, the JAM78S30/MR series ended production in 2023. New procurement relies on warehouse stock or secondary markets, creating risks around module availability for system expansion and challenges matching electrical parameters during warranty service or repowering.
P-type PERC cells are susceptible to Light-Induced Degradation (LID) caused by boron-oxygen defects. Annual degradation reaches 0.55%, while competing N-type TOPCon modules (e.g., GCL SIROT NT10/72GDF or newer JA Solar lines) exhibit 0.30–0.40%/yr. Over a 25-year asset life, this translates to meaningfully lower cumulative energy yield.
The glass-backsheet (monofacial) construction precludes harvesting albedo radiation from the ground. Bifacial alternatives within the same family (JAM78D30 580–605/MB) offer a bifaciality factor of ~70%, delivering a potential energy gain of 5–15% kWh/kWp in ground-mount installations over reflective surfaces.
Peer comparable GCL SIROT NT10/72GDF achieves 23.42% module efficiency at the same maximum power of 605 Wp — approximately 1.8 percentage points above the JAM78S30/MR's 21.6%. This gap stems from newer N-type cell technology and translates to higher energy output per unit footprint in real-world installations.
- Efficiency of 20.7% is 0.6pp below the PERC 550-600W median (21.3%)
- At 207.5 W/m², this panel generates 5.4 W/m² less per unit area than PERC 550-600W median (212.9 W/m²)
- At -0.35%/°C, hot weather performance is typical for PERC 550-600W panels
- #10764 for efficiency, #10419 for temperature performance out of 14005 panels
Specifications
Simulations
Degradation from this panel's own datasheet figures. No inverter, soiling or shading losses.
Found 616 panels of the same or similar size to this one, within ±10 mm. See them here Found 616 panels of the same or similar size to this one, within ±25 mm. See them here Found 616 panels of the same or similar size to this one, within ±50 mm. See them here Found 1813 panels of the same or similar size to this one, within ±100 mm. See them here