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JAM78D40-605/MB/1500V vs JAM72D40-605/MB 9 of 19 identical Swap Change panels

JA Solar JAM78D40-605/MB/1500V vs JA Solar JAM72D40-605/MB

JAM78D40-605/MB/1500V
605 Wp 21.60 % N-type Bifacial
VS
JA Solar JAM72D40-605/MB
JAM72D40-605/MB
605 Wp 23.40 % TOPCon Bifacial
The verdict

JAM72D40-605/MB leads on the differences that matter

The largest is module efficiency: 1.80 pp more efficient. 9 of 19 comparable parameters are identical.

See all 10 differences
How alike are they
9 of 19 comparable
parameters are identical
identical differs
01

What actually differs

10 of 19 parameters
Parameter JAM78D40-605/MB/1500V JAM72D40-605/MB Difference
Module efficiency 21.60 % 23.40 % 1.80 pp more efficient
Power density 216.4 Wp/m² 234.2 Wp/m² 17.8 Wp/m² higher
Weight 34.6 kg 31.8 kg 2.8 kg lighter
Module area 2.795 m² 2.583 m² 0.212 m² apart
Weight per kWp 57.2 kg/kWp 52.6 kg/kWp 4.6 kg/kWp lighter
Temperature coefficient -0.300 %/°C -0.290 %/°C 0.010 %/°C better in heat
Cell technology N-type TOPCon N-type vs TOPCon
Cell count 156 144 12 cells apart
Open-circuit voltage 54.90 V 53.00 V 1.90 V apart
Dimensions 2465x1134x35 mm 2278x1134x30 mm 2465x1134x35 mm vs 2278x1134x30 mm
02

What it means on a roof

Thirty years of production
Each panel's own declared degradation curve, at 1,200 kWh/kWp a year
JAM78D40-605/MB/1500V
20,299 kWh
JAM72D40-605/MB
20,299 kWh
Lifetime gap
No difference
Output when it is hot
Rated power carried across the range a module actually sees
Scenario JAM78D40-605/MB/1500V JAM72D40-605/MB
Standard test conditions 25 °C 100.0% of rated power 605 W 605 W
Cool, bright day 40 °C 95.5% of rated power 578 W 579 W
Typical summer roof 55 °C 91.0% of rated power 551 W 552 W
Hot roof 70 °C 86.5% of rated power 523 W 526 W
03

Full specification

Parameter JAM78D40-605/MB/1500V JAM72D40-605/MB Difference
Power and efficiency
Rated power 605 Wp 605 Wp Same
Module efficiency 21.60 % 23.40 % +1.80 pp for JAM72D40-605/MB
Power density 216.4 Wp/m² 234.2 Wp/m² +17.8 Wp/m² for JAM72D40-605/MB
Open-circuit voltage 54.90 V 53.00 V 1.90 V apart
Voltage at max power 45.80 V 45.05 V Effectively the same
Short-circuit current 14.09 A 14.09 A Same
Current at max power 13.21 A 13.43 A Effectively the same
Temperature
Temperature coefficient -0.300 %/°C -0.290 %/°C +0.010 %/°C for JAM72D40-605/MB
Mechanical
Dimensions 2465x1134x35 mm 2278x1134x30 mm 2465x1134x35 mm vs 2278x1134x30 mm
Module area 2.795 m² 2.583 m² 0.212 m² apart
Weight 34.6 kg 31.8 kg -2.8 kg for JAM72D40-605/MB
Weight per kWp 57.2 kg/kWp 52.6 kg/kWp -4.6 kg/kWp for JAM72D40-605/MB
Warranty and degradation
Product warranty 12 yrs 12 yrs Same
Performance warranty 30 yrs 30 yrs Same
Annual degradation 0.40 %/yr 0.40 %/yr Same
Technology
Cell technology N-type TOPCon N-type vs TOPCon
Cell type Monocrystalline Monocrystalline Same
Cell count 156 144 12 cells apart
Bifacial Yes Yes Same
04

Against the whole database

14,005 panels
Efficiency
#7,652 vs #882
JAM72D40-605/MB leads by 6,770 places
Power density
#7,601 vs #863
JAM72D40-605/MB leads by 6,738 places
Heat behaviour
#6,093 vs #2,165
JAM72D40-605/MB leads by 3,928 places
Weight
#11,122 vs #6,188
JAM72D40-605/MB leads by 4,934 places
Warranty
#21 vs #21
Tied - the same position in the database
Overall
#4,679 vs #2,560
JAM72D40-605/MB leads by 2,119 places
05

More useful comparisons

Open the full database
Same series, other bin
JA Solar JAM78D40-605/MB/1500V vs JA Solar JAM78D40-625/MB/1500V
3 differences, the largest is module efficiency
Same series, other bin
JA Solar JAM78D40-605/MB/1500V vs JA Solar JAM78D40-620/MB/1500V
3 differences, the largest is module efficiency
Same series, other bin
JA Solar JAM78D40-605/MB/1500V vs JA Solar JAM78D40-615/MB/1500V
3 differences, the largest is module efficiency
Same series, other bin
JA Solar JAM78D40-605/MB/1500V vs JA Solar JAM78D40-610/MB/1500V
One difference: module efficiency
Same series, other bin
JA Solar JAM78D40-605/MB/1500V vs JA Solar JAM78D40-600/MB/1500V
The same specification on paper
Same series, other bin
JA Solar JAM72D40-605/MB vs JA Solar JAM72D40-600/MB
One difference: module efficiency
06

Written summary

Checking cache...
07

Questions about this pairing

Which panel is better: JA Solar JAM78D40-605/MB/1500V or JA Solar JAM72D40-605/MB?
According to our database: JA Solar JAM72D40-605/MB has higher module efficiency (23.40% vs 21.60%); JA Solar JAM72D40-605/MB tolerates heat better (temp coeff -0.290%/°C vs -0.300%/°C). See the full spec comparison and 30-year energy simulation above for a complete picture.
What is the efficiency of JA Solar JAM78D40-605/MB/1500V and JA Solar JAM72D40-605/MB?
JA Solar JAM78D40-605/MB/1500V has a module efficiency of 21.60%, while JA Solar JAM72D40-605/MB is 23.40%. Higher efficiency means more electricity from the same roof area - useful when space is limited.
What cell technology does JA Solar JAM78D40-605/MB/1500V use vs JA Solar JAM72D40-605/MB?
JA Solar JAM78D40-605/MB/1500V uses N-type cells; JA Solar JAM72D40-605/MB uses TOPCon. 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 JAM78D40-605/MB/1500V and JA Solar JAM72D40-605/MB?
JA Solar JAM78D40-605/MB/1500V has a 30 years power warranty; JA Solar JAM72D40-605/MB 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 JAM78D40-605/MB/1500V and JA Solar JAM72D40-605/MB bifacial panels?
Both JA Solar JAM78D40-605/MB/1500V and JA Solar JAM72D40-605/MB are bifacial - they capture reflected light from the ground, which can add 5-15% more annual energy on ground-mount or elevated rooftop installations with a light surface beneath.

Shop prices: See 391 JA Solar offers

Every figure here is from the manufacturers' own datasheets - a dash means the value is not published, never an estimate. The thirty-year projection and the temperature scenarios are calculations from those figures, and each states its assumption above.