Longi Solar LR7-54HJBB-495M vs Longi Solar LR8-66HYD-670M
VS
The verdict
15 differences, and they point both ways
The largest is rated power: 175 W more power. 3 of 18 comparable parameters are identical, with 1 more left out because at least one datasheet does not publish it.
See all 15 differencesHow alike are they
3
of 18 comparable
parameters are identical
parameters are identical
identical
differs
not published
01
15 of 18 parameters
What actually differs
Parameter
LR7-54HJBB-495M
LR8-66HYD-670M
Difference
Rated power
495 Wp
670 Wp
175 W more power
Module efficiency
24.30 %
24.80 %
0.50 pp more efficient
Weight
23.5 kg
33.5 kg
10.0 kg lighter
Product warranty
30 yrs
12 yrs
18 yrs longer
Temperature coefficient
-0.240 %/°C
-0.260 %/°C
0.020 %/°C better in heat
Open-circuit voltage
41.35 V
50.12 V
8.77 V apart
Module area
2.041 m²
2.701 m²
0.660 m² apart
Power density
242.5 Wp/m²
248.0 Wp/m²
5.5 Wp/m² higher
Short-circuit current
15.15 A
16.86 A
1.71 A apart
Cell technology
N-type
Back Contact
N-type vs Back Contact
Voltage at max power
34.17 V
41.38 V
7.21 V apart
Cell count
108
132
24 cells apart
Weight per kWp
47.5 kg/kWp
50.0 kg/kWp
2.5 kg/kWp lighter
Current at max power
14.49 A
16.19 A
1.70 A apart
Dimensions
1800x1134x30 mm
2382x1134x30 mm
1800x1134x30 mm vs 2382x1134x30 mm
02
What it means on a roof
Thirty years of production
A 1.0% first-year loss then 0.40% a year, assumed for both panels, at 1,200 kWh/kWp a year
LR7-54HJBB-495M
16,608 kWh
LR8-66HYD-670M
22,480 kWh
Lifetime gap
5,872 kWh
Output when it is hot
Rated power carried across the range a module actually sees
Scenario
LR7-54HJBB-495M
LR8-66HYD-670M
Standard test conditions
25 °C
100.0% of rated power
495 W
670 W
Cool, bright day
40 °C
96.1% of rated power
477 W
644 W
Typical summer roof
55 °C
92.2% of rated power
459 W
618 W
Hot roof
70 °C
88.3% of rated power
442 W
592 W
03
Full specification
Parameter
LR7-54HJBB-495M
LR8-66HYD-670M
Difference
Power and efficiency
Rated power
495 Wp
670 Wp
+175 W for LR8-66HYD-670M
Module efficiency
24.30 %
24.80 %
+0.50 pp for LR8-66HYD-670M
Power density
242.5 Wp/m²
248.0 Wp/m²
+5.5 Wp/m² for LR8-66HYD-670M
Open-circuit voltage
41.35 V
50.12 V
8.77 V apart
Voltage at max power
34.17 V
41.38 V
7.21 V apart
Short-circuit current
15.15 A
16.86 A
1.71 A apart
Current at max power
14.49 A
16.19 A
1.70 A apart
Temperature
Temperature coefficient
-0.240 %/°C
-0.260 %/°C
+0.020 %/°C for LR7-54HJBB-495M
Mechanical
Dimensions
1800x1134x30 mm
2382x1134x30 mm
1800x1134x30 mm vs 2382x1134x30 mm
Module area
2.041 m²
2.701 m²
0.660 m² apart
Weight
23.5 kg
33.5 kg
-10.0 kg for LR7-54HJBB-495M
Weight per kWp
47.5 kg/kWp
50.0 kg/kWp
-2.5 kg/kWp for LR7-54HJBB-495M
Warranty and degradation
Product warranty
30 yrs
12 yrs
+18 yrs for LR7-54HJBB-495M
Performance warranty
30 yrs
30 yrs
Same
Annual degradation
0.35 %/yr
-
Not published by Longi Solar
Technology
Cell technology
N-type
Back Contact
N-type vs Back Contact
Cell type
Monocrystalline
Monocrystalline
Same
Cell count
108
132
24 cells apart
Bifacial
Yes
Yes
Same
04
14,005 panels
Against the whole database
Efficiency
#131
vs
#12
LR8-66HYD-670M leads by 119 places
Power density
#159
vs
#14
LR8-66HYD-670M leads by 145 places
Heat behaviour
#13
vs
#511
LR7-54HJBB-495M leads by 498 places
Weight
#1,708
vs
#3,317
LR7-54HJBB-495M leads by 1,609 places
Warranty
#21
vs
#21
Tied - the same position in the database
Overall
#1,810
vs
#490
LR8-66HYD-670M leads by 1,320 places
05
Open the full database
More useful comparisons
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Longi Solar LR7-54HJBB-495M vs Longi Solar LR7-54HJBB-505M
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Longi Solar LR7-54HJBB-495M vs Longi Solar LR7-54HJBB-500M
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Longi Solar LR7-54HJBB-495M vs Longi Solar LR7-54HJBB-490M
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Same series, other bin
Longi Solar LR8-66HYD-670M vs Longi Solar LR8-66HYD-665M
One difference: module efficiency
Same series, other bin
Longi Solar LR8-66HYD-670M vs Longi Solar LR8-66HYD-660M
3 differences, the largest is module efficiency
Same series, other bin
Longi Solar LR8-66HYD-670M vs Longi Solar LR7-72HYD-660M
9 differences, the largest is module efficiency
06
Written summary
Checking cache...
07
Questions about this pairing
Which panel is better: Longi Solar LR7-54HJBB-495M or Longi Solar LR8-66HYD-670M?
According to our database: Longi Solar LR8-66HYD-670M has higher module efficiency (24.80% vs 24.30%); Longi Solar LR7-54HJBB-495M tolerates heat better (temp coeff -0.240%/°C vs -0.260%/°C). See the full spec comparison and 30-year energy simulation above for a complete picture.
What is the efficiency of Longi Solar LR7-54HJBB-495M and Longi Solar LR8-66HYD-670M?
Longi Solar LR7-54HJBB-495M has a module efficiency of 24.30%, while Longi Solar LR8-66HYD-670M is 24.80%. Higher efficiency means more electricity from the same roof area - useful when space is limited.
What cell technology does Longi Solar LR7-54HJBB-495M use vs Longi Solar LR8-66HYD-670M?
Longi Solar LR7-54HJBB-495M uses N-type cells; Longi Solar LR8-66HYD-670M uses Back Contact. 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 Longi Solar LR7-54HJBB-495M and Longi Solar LR8-66HYD-670M?
Longi Solar LR7-54HJBB-495M has a 30 years power warranty; Longi Solar LR8-66HYD-670M 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 Longi Solar LR7-54HJBB-495M and Longi Solar LR8-66HYD-670M bifacial panels?
Both Longi Solar LR7-54HJBB-495M and Longi Solar LR8-66HYD-670M 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 172 Longi 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.

