---
title: "JA Solar JAM72S30-540/MR/1500V vs JA Solar JAM78D30-605/MB/1500V - Solar Panel Comparison | ComparePV"
description: "Compare JA Solar JAM72S30-540/MR/1500V vs JA Solar JAM78D30-605/MB/1500V side by side: what actually differs, output when it is hot, thirty-year production, and the full specification."
source: "https://comparepv.com/compare/shanghai-ja-solar-technology-co-ltd-jam72s30-540-mr-1500v/shanghai-ja-solar-technology-co-ltd-jam78d30-605-mb-1500v"
image: "https://comparepv.com/og/compare/panels/shanghai-ja-solar-technology-co-ltd-jam72s30-540-mr-1500v/shanghai-ja-solar-technology-co-ltd-jam78d30-605-mb-1500v.png"
updated: 2026-09-11
---

# JA Solar JAM72S30-540/MR/1500V vs JA Solar JAM78D30-605/MB/1500V

JAM78D30-605/MB/1500V leads on the differences that matter

The largest is module efficiency: 0.70 pp more efficient. 6 of 19 comparable parameters are identical.


## The two panels


| Attribute | A | B |
| --- | --- | --- |
| Panel | [JA Solar JAM72S30-540/MR/1500V](https://comparepv.com/panel/shanghai-ja-solar-technology-co-ltd-jam72s30-540-mr-1500v) | [JA Solar JAM78D30-605/MB/1500V](https://comparepv.com/panel/shanghai-ja-solar-technology-co-ltd-jam78d30-605-mb-1500v) |
| Manufacturer | JA Solar | JA Solar |
| Power | 540 Wp | 605 Wp |
| Efficiency | 20.90 % | 21.60 % |
| Technology | PERC | PERC |


## Where they differ

Ranked by how much the difference matters, not by datasheet order.


| Parameter | JAM72S30-540/MR/1500V | JAM78D30-605/MB/1500V | Difference |
| --- | --- | --- | --- |
| Module efficiency | 20.90 % | 21.60 % | +0.70 pp for JAM78D30-605/MB/1500V |
| Rated power | 540 Wp | 605 Wp | +65 W for JAM78D30-605/MB/1500V |
| Performance warranty | 25 yrs | 30 yrs | +5 yrs for JAM78D30-605/MB/1500V |
| Weight | 27.3 kg | 33.4 kg | -6.1 kg for JAM72S30-540/MR/1500V |
| Power density | 209.0 Wp/m² | 216.4 Wp/m² | +7.4 Wp/m² for JAM78D30-605/MB/1500V |
| Annual degradation | 0.55 %/yr | 0.45 %/yr | -0.10 %/yr for JAM78D30-605/MB/1500V |
| Open-circuit voltage | 49.60 V | 53.61 V | 4.01 V apart |
| Module area | 2.583 m² | 2.795 m² | 0.212 m² apart |
| Weight per kWp | 50.6 kg/kWp | 55.2 kg/kWp | -4.7 kg/kWp for JAM72S30-540/MR/1500V |
| Cell count | 144 | 156 | 12 cells apart |
| Voltage at max power | 41.64 V | 45.53 V | 3.89 V apart |
| Bifacial | No | Yes | No vs Yes |
| Dimensions | 2278x1134x30 mm | 2465x1134x35 mm | 2278x1134x30 mm vs 2465x1134x35 mm |


## Every compared parameter


| Parameter | JAM72S30-540/MR/1500V | JAM78D30-605/MB/1500V |
| --- | --- | --- |
| Rated power | 540 Wp | 605 Wp |
| Module efficiency | 20.90 % | 21.60 % |
| Power density | 209.0 Wp/m² | 216.4 Wp/m² |
| Open-circuit voltage | 49.60 V | 53.61 V |
| Voltage at max power | 41.64 V | 45.53 V |
| Short-circuit current | 13.86 A | 14.08 A |
| Current at max power | 12.97 A | 13.29 A |
| Temperature coefficient | -0.350 %/°C | -0.350 %/°C |
| Dimensions | 2278x1134x30 mm | 2465x1134x35 mm |
| Module area | 2.583 m² | 2.795 m² |
| Weight | 27.3 kg | 33.4 kg |
| Weight per kWp | 50.6 kg/kWp | 55.2 kg/kWp |
| Product warranty | 12 yrs | 12 yrs |
| Performance warranty | 25 yrs | 30 yrs |
| Annual degradation | 0.55 %/yr | 0.45 %/yr |
| Cell technology | PERC | PERC |
| Cell type | Monocrystalline | Monocrystalline |
| Cell count | 144 | 156 |
| Bifacial | No | Yes |


## Thirty-year yield

Each panel's own declared degradation curve, at 1,200 kWh/kWp a year

Same temp coeff. for both panels (-0.350 %/°C), so a warmer roof scales both curves by the same factor: the totals fall together and neither panel gains on the other.

- **Cumulative output, JAM72S30-540/MR/1500V:** 17,501 kWh
- **Cumulative output, JAM78D30-605/MB/1500V:** 19,923 kWh
- **Gap:** 2,422 kWh


## Output when hot


| Condition | Cell temperature | JAM72S30-540/MR/1500V | JAM78D30-605/MB/1500V | Retained |
| --- | --- | --- | --- | --- |
| Standard test conditions | 25 °C | 540 W | 605 W | 100.0% of rated power |
| Cool, bright day | 40 °C | 512 W | 573 W | 94.8% of rated power |
| Typical summer roof | 55 °C | 483 W | 541 W | 89.5% of rated power |
| Hot roof | 70 °C | 455 W | 510 W | 84.2% of rated power |


## Against the whole database


| Measure | JAM72S30-540/MR/1500V | JAM78D30-605/MB/1500V | Out of | Note |
| --- | --- | --- | --- | --- |
| Efficiency | #10,148 | #7,716 | 14,129 | JAM78D30-605/MB/1500V leads by 2,432 places |
| Power density | #10,176 | #7,665 | 14,129 | JAM78D30-605/MB/1500V leads by 2,511 places |
| Heat behaviour | #10,489 | #10,489 | 14,129 | Tied - the same position in the database |
| Weight | #3,965 | #9,735 | 14,129 | JAM72S30-540/MR/1500V leads by 5,770 places |
| Warranty | #9,912 | #21 | 14,129 | JAM78D30-605/MB/1500V leads by 9,891 places |
| Overall | #8,957 | #4,714 | 14,129 | JAM78D30-605/MB/1500V leads by 4,243 places |


## Questions


### Which panel is better: JA Solar JAM72S30-540/MR/1500V or JA Solar JAM78D30-605/MB/1500V?

According to our database: **JA Solar JAM78D30-605/MB/1500V** has higher module efficiency (**21.60%** vs **20.90%**). See the full spec comparison and 30-year energy simulation above for a complete picture.


### What is the efficiency of JA Solar JAM72S30-540/MR/1500V and JA Solar JAM78D30-605/MB/1500V?

**JA Solar JAM72S30-540/MR/1500V** has a module efficiency of **20.90%**, while **JA Solar JAM78D30-605/MB/1500V** is **21.60%**. Higher efficiency means more electricity from the same roof area - useful when space is limited.


### What cell technology does JA Solar JAM72S30-540/MR/1500V use vs JA Solar JAM78D30-605/MB/1500V?

**JA Solar JAM72S30-540/MR/1500V** uses **PERC** cells; **JA Solar JAM78D30-605/MB/1500V** uses **PERC**. 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 JAM72S30-540/MR/1500V and JA Solar JAM78D30-605/MB/1500V?

**JA Solar JAM72S30-540/MR/1500V** has a **25 years** power warranty; **JA Solar JAM78D30-605/MB/1500V** 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 JAM72S30-540/MR/1500V and JA Solar JAM78D30-605/MB/1500V bifacial panels?

**JA Solar JAM78D30-605/MB/1500V** is bifacial (captures light from both faces); **JA Solar JAM72S30-540/MR/1500V** is monofacial. Bifacial panels work best on ground mounts or raised structures with a light-coloured surface underneath.


## Related comparisons

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- [JA Solar JAM72S30-540/MR/1500V vs JA Solar JAM72D30-580/LB/1500V](https://comparepv.com/compare/shanghai-ja-solar-technology-co-ltd-jam72s30-540-mr-1500v/ja-solar-jam72d30-580-lb-1500v) - 13 differences, the largest is module efficiency


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Source: https://comparepv.com/compare/shanghai-ja-solar-technology-co-ltd-jam72s30-540-mr-1500v/shanghai-ja-solar-technology-co-ltd-jam78d30-605-mb-1500v

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.