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JAM66D46-740/LB vs JAM60S21-365/MR/1000V 3 of 19 identical Swap Change panels

JA Solar JAM66D46-740/LB vs JA Solar JAM60S21-365/MR/1000V

JA Solar JAM66D46-740/LB
JAM66D46-740/LB
740 Wp 23.80 % TOPCon Bifacial
Open panel page Datasheet PDF
VS
JAM60S21-365/MR/1000V
365 Wp 19.60 % PERC
Open panel page Datasheet PDF
The verdict

JAM66D46-740/LB leads on the differences that matter

The largest is module efficiency: 4.20 pp more efficient. 3 of 19 comparable parameters are identical.

See all 16 differences
How alike are they
3 of 19 comparable
parameters are identical
identical differs
01

What actually differs

16 of 19 parameters
Parameter JAM66D46-740/LB JAM60S21-365/MR/1000V Difference
Module efficiency 23.80 % 19.60 % 4.20 pp more efficient
Temperature coefficient -0.290 %/°C -0.350 %/°C 0.060 %/°C better in heat
Rated power 740 Wp 365 Wp 375 W more power
Power density 238.2 Wp/m² 196.1 Wp/m² 42.1 Wp/m² higher
Performance warranty 30 yrs 25 yrs 5 yrs longer
Annual degradation 0.40 %/yr 0.55 %/yr 0.15 %/yr slower
Weight 38.2 kg 18.8 kg 19.4 kg lighter
Open-circuit voltage 49.80 V 41.13 V 8.67 V apart
Short-circuit current 18.73 A 11.30 A 7.43 A apart
Module area 3.106 m² 1.861 m² 1.245 m² apart
Cell technology TOPCon PERC TOPCon vs PERC
Voltage at max power 41.96 V 33.96 V 8.00 V apart
Current at max power 17.64 A 10.75 A 6.89 A apart
Cell count 132 120 12 cells apart
Bifacial Yes No Yes vs No
Dimensions 2384x1303x33 mm 1769x1052x30 mm 2384x1303x33 mm vs 1769x1052x30 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
JAM66D46-740/LB
24,828 kWh
JAM60S21-365/MR/1000V
11,829 kWh
Lifetime gap
12,999 kWh
Output when it is hot
Rated power carried across the range a module actually sees
Scenario JAM66D46-740/LB JAM60S21-365/MR/1000V
Standard test conditions 25 °C 100.0% of rated power 740 W 365 W
Cool, bright day 40 °C 94.8% of rated power 708 W 346 W
Typical summer roof 55 °C 89.5% of rated power 676 W 327 W
Hot roof 70 °C 84.2% of rated power 643 W 308 W
03

Full specification

Parameter JAM66D46-740/LB JAM60S21-365/MR/1000V Difference
Power and efficiency
Rated power 740 Wp 365 Wp +375 W for JAM66D46-740/LB
Module efficiency 23.80 % 19.60 % +4.20 pp for JAM66D46-740/LB
Power density 238.2 Wp/m² 196.1 Wp/m² +42.1 Wp/m² for JAM66D46-740/LB
Open-circuit voltage 49.80 V 41.13 V 8.67 V apart
Voltage at max power 41.96 V 33.96 V 8.00 V apart
Short-circuit current 18.73 A 11.30 A 7.43 A apart
Current at max power 17.64 A 10.75 A 6.89 A apart
Temperature
Temperature coefficient -0.290 %/°C -0.350 %/°C +0.060 %/°C for JAM66D46-740/LB
Mechanical
Dimensions 2384x1303x33 mm 1769x1052x30 mm 2384x1303x33 mm vs 1769x1052x30 mm
Module area 3.106 m² 1.861 m² 1.245 m² apart
Weight 38.2 kg 18.8 kg -19.4 kg for JAM60S21-365/MR/1000V
Weight per kWp 51.6 kg/kWp 51.5 kg/kWp Effectively the same
Warranty and degradation
Product warranty 12 yrs 12 yrs Same
Performance warranty 30 yrs 25 yrs +5 yrs for JAM66D46-740/LB
Annual degradation 0.40 %/yr 0.55 %/yr -0.15 %/yr for JAM66D46-740/LB
Technology
Cell technology TOPCon PERC TOPCon vs PERC
Cell type Monocrystalline Monocrystalline Same
Cell count 132 120 12 cells apart
Bifacial Yes No Yes vs No
04

Against the whole database

14,129 panels
Efficiency
#462 vs #12,677
JAM66D46-740/LB leads by 12,215 places
Power density
#460 vs #12,671
JAM66D46-740/LB leads by 12,211 places
Heat behaviour
#2,220 vs #10,489
JAM66D46-740/LB leads by 8,269 places
Weight
#5,026 vs #4,905
JAM60S21-365/MR/1000V leads by 121 places
Warranty
#21 vs #9,912
JAM66D46-740/LB leads by 9,891 places
Overall
#185 vs #12,806
JAM66D46-740/LB leads by 12,621 places
05

More useful comparisons

Open the full database
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3 differences, the largest is module efficiency
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JA Solar JAM66D46-740/LB vs JA Solar JAM66D46-720/LB
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JA Solar JAM66D46-740/LB vs JA Solar JAM66D46-715/LB
4 differences, the largest is module efficiency
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JA Solar JAM66D46-740/LB vs JA Solar JAM66D46-710/LB
6 differences, the largest is module efficiency
06

Written summary

07

Questions about this pairing

Which panel is better: JA Solar JAM66D46-740/LB or JA Solar JAM60S21-365/MR/1000V?
According to our database: JA Solar JAM66D46-740/LB has higher module efficiency (23.80% vs 19.60%); JA Solar JAM66D46-740/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 JAM66D46-740/LB and JA Solar JAM60S21-365/MR/1000V?
JA Solar JAM66D46-740/LB has a module efficiency of 23.80%, while JA Solar JAM60S21-365/MR/1000V is 19.60%. Higher efficiency means more electricity from the same roof area - useful when space is limited.
What cell technology does JA Solar JAM66D46-740/LB use vs JA Solar JAM60S21-365/MR/1000V?
JA Solar JAM66D46-740/LB uses TOPCon cells; JA Solar JAM60S21-365/MR/1000V 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 JAM66D46-740/LB and JA Solar JAM60S21-365/MR/1000V?
JA Solar JAM66D46-740/LB has a 30 years power warranty; JA Solar JAM60S21-365/MR/1000V has a 25 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 JAM66D46-740/LB and JA Solar JAM60S21-365/MR/1000V bifacial panels?
JA Solar JAM66D46-740/LB is bifacial (captures light from both faces); JA Solar JAM60S21-365/MR/1000V is monofacial. Bifacial panels work best on ground mounts or raised structures with a light-coloured surface underneath.

Shop prices: See 330 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.