Longi Solar LR8-66HYD-670M vs Longi Solar LR5-72HGD-590M
VS
The verdict
LR8-66HYD-670M leads on the differences that matter
The largest is module efficiency: 2.00 pp more efficient. 4 of 18 comparable parameters are identical, with 1 more left out because at least one datasheet does not publish it.
See all 14 differencesHow alike are they
4
of 18 comparable
parameters are identical
parameters are identical
identical
differs
not published
01
14 of 18 parameters
What actually differs
Parameter
LR8-66HYD-670M
LR5-72HGD-590M
Difference
Module efficiency
24.80 %
22.80 %
2.00 pp more efficient
Rated power
670 Wp
590 Wp
80 W more power
Power density
248.0 Wp/m²
228.4 Wp/m²
19.6 Wp/m² higher
Temperature coefficient
-0.260 %/°C
-0.280 %/°C
0.020 %/°C better in heat
Short-circuit current
16.86 A
14.38 A
2.48 A apart
Module area
2.701 m²
2.583 m²
0.118 m² apart
Weight per kWp
50.0 kg/kWp
53.9 kg/kWp
3.9 kg/kWp lighter
Weight
33.5 kg
31.8 kg
1.7 kg lighter
Cell technology
Back Contact
N-type
Back Contact vs N-type
Current at max power
16.19 A
13.59 A
2.60 A apart
Cell count
132
144
12 cells apart
Open-circuit voltage
50.12 V
51.63 V
1.51 V apart
Voltage at max power
41.38 V
43.44 V
2.06 V apart
Dimensions
2382x1134x30 mm
2278x1134x30 mm
2382x1134x30 mm vs 2278x1134x30 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
LR8-66HYD-670M
22,480 kWh
LR5-72HGD-590M
19,796 kWh
Lifetime gap
2,684 kWh
Output when it is hot
Rated power carried across the range a module actually sees
Scenario
LR8-66HYD-670M
LR5-72HGD-590M
Standard test conditions
25 °C
100.0% of rated power
670 W
590 W
Cool, bright day
40 °C
95.8% of rated power
644 W
565 W
Typical summer roof
55 °C
91.6% of rated power
618 W
540 W
Hot roof
70 °C
87.4% of rated power
592 W
516 W
03
Full specification
Parameter
LR8-66HYD-670M
LR5-72HGD-590M
Difference
Power and efficiency
Rated power
670 Wp
590 Wp
+80 W for LR8-66HYD-670M
Module efficiency
24.80 %
22.80 %
+2.00 pp for LR8-66HYD-670M
Power density
248.0 Wp/m²
228.4 Wp/m²
+19.6 Wp/m² for LR8-66HYD-670M
Open-circuit voltage
50.12 V
51.63 V
1.51 V apart
Voltage at max power
41.38 V
43.44 V
2.06 V apart
Short-circuit current
16.86 A
14.38 A
2.48 A apart
Current at max power
16.19 A
13.59 A
2.60 A apart
Temperature
Temperature coefficient
-0.260 %/°C
-0.280 %/°C
+0.020 %/°C for LR8-66HYD-670M
Mechanical
Dimensions
2382x1134x30 mm
2278x1134x30 mm
2382x1134x30 mm vs 2278x1134x30 mm
Module area
2.701 m²
2.583 m²
0.118 m² apart
Weight
33.5 kg
31.8 kg
-1.7 kg for LR5-72HGD-590M
Weight per kWp
50.0 kg/kWp
53.9 kg/kWp
-3.9 kg/kWp for LR8-66HYD-670M
Warranty and degradation
Product warranty
12 yrs
12 yrs
Same
Performance warranty
30 yrs
30 yrs
Same
Annual degradation
-
0.40 %/yr
Not published by Longi Solar
Technology
Cell technology
Back Contact
N-type
Back Contact vs N-type
Cell type
Monocrystalline
Monocrystalline
Same
Cell count
132
144
12 cells apart
Bifacial
Yes
Yes
Same
04
14,005 panels
Against the whole database
Efficiency
#12
vs
#2,714
LR8-66HYD-670M leads by 2,702 places
Power density
#14
vs
#2,598
LR8-66HYD-670M leads by 2,584 places
Heat behaviour
#511
vs
#1,309
LR8-66HYD-670M leads by 798 places
Weight
#3,317
vs
#8,021
LR8-66HYD-670M leads by 4,704 places
Warranty
#21
vs
#21
Tied - the same position in the database
Overall
#490
vs
#3,801
LR8-66HYD-670M leads by 3,311 places
05
Open the full database
More useful comparisons
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
Same series, other bin
Longi Solar LR8-66HYD-670M vs Longi Solar LR8-66HYD-655M
3 differences, the largest is module efficiency
Same series, other bin
Longi Solar LR8-66HYD-670M vs Longi Solar LR7-72HYD-655M
9 differences, the largest is module efficiency
Same series, other bin
Longi Solar LR8-66HYD-670M vs Longi Solar LR8-66HYD-650M
3 differences, the largest is module efficiency
06
Written summary
Checking cache...
07
Questions about this pairing
Which panel is better: Longi Solar LR8-66HYD-670M or Longi Solar LR5-72HGD-590M?
According to our database: Longi Solar LR8-66HYD-670M has higher module efficiency (24.80% vs 22.80%); Longi Solar LR8-66HYD-670M tolerates heat better (temp coeff -0.260%/°C vs -0.280%/°C). See the full spec comparison and 30-year energy simulation above for a complete picture.
What is the efficiency of Longi Solar LR8-66HYD-670M and Longi Solar LR5-72HGD-590M?
Longi Solar LR8-66HYD-670M has a module efficiency of 24.80%, while Longi Solar LR5-72HGD-590M is 22.80%. Higher efficiency means more electricity from the same roof area - useful when space is limited.
What cell technology does Longi Solar LR8-66HYD-670M use vs Longi Solar LR5-72HGD-590M?
Longi Solar LR8-66HYD-670M uses Back Contact cells; Longi Solar LR5-72HGD-590M uses N-type. 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 LR8-66HYD-670M and Longi Solar LR5-72HGD-590M?
Longi Solar LR8-66HYD-670M has a 30 years power warranty; Longi Solar LR5-72HGD-590M 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 LR8-66HYD-670M and Longi Solar LR5-72HGD-590M bifacial panels?
Both Longi Solar LR8-66HYD-670M and Longi Solar LR5-72HGD-590M 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 174 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.

