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JAM72S20-445/MR vs JAM66D46-735/LB 4 of 19 identical Swap Change panels

JA Solar JAM72S20-445/MR vs JA Solar JAM66D46-735/LB

JA Solar JAM72S20-445/MR
JAM72S20-445/MR
445 Wp 20.00 % PERC
VS
JA Solar JAM66D46-735/LB
JAM66D46-735/LB
735 Wp 23.70 % TOPCon Bifacial
The verdict

JAM66D46-735/LB leads on the differences that matter

The largest is module efficiency: 3.70 pp more efficient. 4 of 19 comparable parameters are identical.

See all 15 differences
How alike are they
4 of 19 comparable
parameters are identical
identical differs
01

What actually differs

15 of 19 parameters
Parameter JAM72S20-445/MR JAM66D46-735/LB Difference
Module efficiency 20.00 % 23.70 % 3.70 pp more efficient
Temperature coefficient -0.350 %/°C -0.290 %/°C 0.060 %/°C better in heat
Rated power 445 Wp 735 Wp 290 W more power
Power density 200.3 Wp/m² 236.6 Wp/m² 36.3 Wp/m² higher
Performance warranty 25 yrs 30 yrs 5 yrs longer
Annual degradation 0.55 %/yr 0.40 %/yr 0.15 %/yr slower
Weight 24.5 kg 38.2 kg 13.7 kg lighter
Short-circuit current 11.32 A 18.70 A 7.38 A apart
Module area 2.222 m² 3.106 m² 0.885 m² apart
Cell technology PERC TOPCon PERC vs TOPCon
Weight per kWp 55.1 kg/kWp 52.0 kg/kWp 3.1 kg/kWp lighter
Current at max power 10.80 A 17.60 A 6.80 A apart
Cell count 144 132 12 cells apart
Bifacial No Yes No vs Yes
Dimensions 2112x1052x35 mm 2384x1303x33 mm 2112x1052x35 mm vs 2384x1303x33 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
JAM72S20-445/MR
14,422 kWh
JAM66D46-735/LB
24,661 kWh
Lifetime gap
10,239 kWh
Output when it is hot
Rated power carried across the range a module actually sees
Scenario JAM72S20-445/MR JAM66D46-735/LB
Standard test conditions 25 °C 100.0% of rated power 445 W 735 W
Cool, bright day 40 °C 94.8% of rated power 422 W 703 W
Typical summer roof 55 °C 89.5% of rated power 398 W 671 W
Hot roof 70 °C 84.2% of rated power 375 W 639 W
03

Full specification

Parameter JAM72S20-445/MR JAM66D46-735/LB Difference
Power and efficiency
Rated power 445 Wp 735 Wp +290 W for JAM66D46-735/LB
Module efficiency 20.00 % 23.70 % +3.70 pp for JAM66D46-735/LB
Power density 200.3 Wp/m² 236.6 Wp/m² +36.3 Wp/m² for JAM66D46-735/LB
Open-circuit voltage 49.56 V 49.60 V Effectively the same
Voltage at max power 41.21 V 41.77 V Effectively the same
Short-circuit current 11.32 A 18.70 A 7.38 A apart
Current at max power 10.80 A 17.60 A 6.80 A apart
Temperature
Temperature coefficient -0.350 %/°C -0.290 %/°C +0.060 %/°C for JAM66D46-735/LB
Mechanical
Dimensions 2112x1052x35 mm 2384x1303x33 mm 2112x1052x35 mm vs 2384x1303x33 mm
Module area 2.222 m² 3.106 m² 0.885 m² apart
Weight 24.5 kg 38.2 kg -13.7 kg for JAM72S20-445/MR
Weight per kWp 55.1 kg/kWp 52.0 kg/kWp -3.1 kg/kWp for JAM66D46-735/LB
Warranty and degradation
Product warranty 12 yrs 12 yrs Same
Performance warranty 25 yrs 30 yrs +5 yrs for JAM66D46-735/LB
Annual degradation 0.55 %/yr 0.40 %/yr -0.15 %/yr for JAM66D46-735/LB
Technology
Cell technology PERC TOPCon PERC vs TOPCon
Cell type Monocrystalline Monocrystalline Same
Cell count 144 132 12 cells apart
Bifacial No Yes No vs Yes
04

Against the whole database

14,005 panels
Efficiency
#12,214 vs #517
JAM66D46-735/LB leads by 11,697 places
Power density
#12,162 vs #582
JAM66D46-735/LB leads by 11,580 places
Heat behaviour
#10,419 vs #2,165
JAM66D46-735/LB leads by 8,254 places
Weight
#9,435 vs #5,413
JAM66D46-735/LB leads by 4,022 places
Warranty
#9,798 vs #21
JAM66D46-735/LB leads by 9,777 places
Overall
#11,694 vs #233
JAM66D46-735/LB leads by 11,461 places
05

More useful comparisons

Open the full database
Same series, other bin
JA Solar JAM72S20-445/MR vs JA Solar JAM72S20-470/MR
5 differences, the largest is module efficiency
Same series, other bin
JA Solar JAM72S20-445/MR vs JA Solar JAM72S20-465/MR
5 differences, the largest is module efficiency
Same series, other bin
JA Solar JAM72S20-445/MR vs JA Solar JAM72S20-460/MR
3 differences, the largest is module efficiency
Same series, other bin
JA Solar JAM72S20-445/MR vs JA Solar JAM72S20-455/MR
3 differences, the largest is module efficiency
Same series, other bin
JA Solar JAM72S20-445/MR vs JA Solar JAM72S20-450/MR
One difference: module efficiency
Same series, other bin
JA Solar JAM66D46-735/LB vs JA Solar JAM66D46-740/LB
The same specification on paper
06

Written summary

Checking cache...
07

Questions about this pairing

Which panel is better: JA Solar JAM72S20-445/MR or JA Solar JAM66D46-735/LB?
According to our database: JA Solar JAM66D46-735/LB has higher module efficiency (23.70% vs 20.00%); JA Solar JAM66D46-735/LB tolerates heat better (temp coeff -0.290%/°C vs -0.350%/°C). See the full spec comparison and 30-year energy simulation above for a complete picture.
What is the efficiency of JA Solar JAM72S20-445/MR and JA Solar JAM66D46-735/LB?
JA Solar JAM72S20-445/MR has a module efficiency of 20.00%, while JA Solar JAM66D46-735/LB is 23.70%. Higher efficiency means more electricity from the same roof area - useful when space is limited.
What cell technology does JA Solar JAM72S20-445/MR use vs JA Solar JAM66D46-735/LB?
JA Solar JAM72S20-445/MR uses PERC cells; JA Solar JAM66D46-735/LB 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 JAM72S20-445/MR and JA Solar JAM66D46-735/LB?
JA Solar JAM72S20-445/MR has a 25 years power warranty; JA Solar JAM66D46-735/LB 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 JAM72S20-445/MR and JA Solar JAM66D46-735/LB bifacial panels?
JA Solar JAM66D46-735/LB is bifacial (captures light from both faces); JA Solar JAM72S20-445/MR is monofacial. Bifacial panels work best on ground mounts or raised structures with a light-coloured surface underneath.

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.