JA Solar — China
JAM 420W A Max
The JA Solar JAM 420W A Max is a 420W N-Type TOPCon solar panel with 20.2% efficiency. Backed by a 30-year warranty.
Standard TierFEOC: RestrictedBifacial
420W
Wattage
20.2%
Efficiency
N-Type TOPCon
Cell Type
30 years
Warranty
Full Specifications
- Brand
- JA Solar
- Model
- JAM 420W A Max
- Series
- JAM
- Wattage
- 420W
- Module Efficiency
- 20.2%
- Cell Type
- N-Type TOPCon
- Dimensions
- 66-80" x 39-41"
- Weight
- 48 lbs
- Warranty
- 30 years
- Est. Price Per Watt
- $2.08
- Est. 7kW System Cost
- $14,560
- Est. 10kW System Cost
- $20,800
- Temperature Coefficient
- -0.25%/°C
- Bifacial
- Yes
- Origin
- China
- FEOC Status
- fail
Other JA Solar Panels
| Model | Wattage | Efficiency | Cell | $/W |
|---|---|---|---|---|
| JAM 485W D | 485W | 22.8% | N-Type TOPCon | $2.69 |
| DeepBlue 485W D | 485W | 22.8% | N-Type TOPCon | $2.69 |
| JAM72 485W D | 485W | 22.8% | N-Type TOPCon | $2.69 |
| JAM54 485W D | 485W | 22.8% | N-Type TOPCon | $2.69 |
| DeepBlue 3.0 485W D | 485W | 22.8% | N-Type TOPCon | $2.69 |
Similar Wattage Panels (Competitors)
| Panel | Wattage | Efficiency | $/W |
|---|---|---|---|
| Maxeon Maxeon 3 450W D Plus | 450W | 23.3% | $4.61 |
| Maxeon Maxeon 6 450W D Plus | 450W | 23.3% | $4.61 |
| Maxeon Maxeon 7 450W D Plus | 450W | 23.3% | $4.61 |
| Maxeon Maxeon Air 450W D Plus | 450W | 23.3% | $4.61 |
Frequently Asked Questions
How much does a 420W JA Solar JAM 420W A Max cost?
The JA Solar JAM 420W A Max costs approximately $874 per panel ($$2.08/W). A typical 7kW system using this panel would cost around $14,560 before incentives.
⚠ The 30% Federal Solar Tax Credit (48E/ITC) expired July 4, 2026.
Selecting 30% ITC assumes you began construction before this deadline. Most new purchases no longer qualify.Learn about your options after the deadline →
Is the JA Solar JAM 420W A Max a good solar panel?
The JA Solar JAM 420W A Max has 20.2% efficiency and a 30 years warranty, placing it in the standard tier. This is a solid mid-range panel suitable for most residential installations.
How many JA Solar JAM 420W A Max panels do I need?
For a typical 7kW residential system, you'd need approximately 17 panels. For a 10kW system, plan for about 24 panels. The exact number depends on your roof space, energy usage, and local sun hours.