Heckert Solar ZEUS 1.2-280 vs Heckert Solar ZEUS 2.1-635
VS
The verdict
1.2-280 leads on the differences that matter
The largest is rated power: 355 W more power. 7 of 19 comparable parameters are identical.
See all 12 differencesHow alike are they
7
of 19 comparable
parameters are identical
parameters are identical
identical
differs
01
12 of 19 parameters
What actually differs
Parameter
1.2-280
2.1-635
Difference
Rated power
280 Wp
635 Wp
355 W more power
Weight
14.3 kg
32.5 kg
18.2 kg lighter
Product warranty
30 yrs
12 yrs
18 yrs longer
Temperature coefficient
-0.260 %/°C
-0.280 %/°C
0.020 %/°C better in heat
Open-circuit voltage
24.11 V
49.60 V
25.49 V apart
Module area
1.201 m²
2.701 m²
1.500 m² apart
Short-circuit current
14.72 A
16.26 A
1.54 A apart
Cell technology
Back Contact
N-type
Back Contact vs N-type
Voltage at max power
20.49 V
41.24 V
20.75 V apart
Cell count
64
132
68 cells apart
Current at max power
13.67 A
15.40 A
1.73 A apart
Dimensions
1560x770x35 mm
2382x1134x30 mm
1560x770x35 mm vs 2382x1134x30 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
1.2-280
9,221 kWh
2.1-635
20,911 kWh
Lifetime gap
11,690 kWh
Output when it is hot
Rated power carried across the range a module actually sees
Scenario
1.2-280
2.1-635
Standard test conditions
25 °C
100.0% of rated power
280 W
635 W
Cool, bright day
40 °C
95.8% of rated power
269 W
608 W
Typical summer roof
55 °C
91.6% of rated power
258 W
582 W
Hot roof
70 °C
87.4% of rated power
247 W
555 W
03
Full specification
Parameter
1.2-280
2.1-635
Difference
Power and efficiency
Rated power
280 Wp
635 Wp
+355 W for 2.1-635
Module efficiency
23.31 %
23.50 %
Effectively the same
Power density
233.1 Wp/m²
235.1 Wp/m²
Effectively the same
Open-circuit voltage
24.11 V
49.60 V
25.49 V apart
Voltage at max power
20.49 V
41.24 V
20.75 V apart
Short-circuit current
14.72 A
16.26 A
1.54 A apart
Current at max power
13.67 A
15.40 A
1.73 A apart
Temperature
Temperature coefficient
-0.260 %/°C
-0.280 %/°C
+0.020 %/°C for 1.2-280
Mechanical
Dimensions
1560x770x35 mm
2382x1134x30 mm
1560x770x35 mm vs 2382x1134x30 mm
Module area
1.201 m²
2.701 m²
1.500 m² apart
Weight
14.3 kg
32.5 kg
-18.2 kg for 1.2-280
Weight per kWp
51.1 kg/kWp
51.2 kg/kWp
Effectively the same
Warranty and degradation
Product warranty
30 yrs
12 yrs
+18 yrs for 1.2-280
Performance warranty
30 yrs
30 yrs
Same
Annual degradation
0.45 %/yr
0.45 %/yr
Same
Technology
Cell technology
Back Contact
N-type
Back Contact vs N-type
Cell type
Monocrystalline
Monocrystalline
Same
Cell count
64
132
68 cells apart
Bifacial
Yes
Yes
Same
04
14,129 panels
Against the whole database
Efficiency
#1,055
vs
#749
2.1-635 leads by 306 places
Power density
#1,136
vs
#777
2.1-635 leads by 359 places
Heat behaviour
#515
vs
#1,347
1.2-280 leads by 832 places
Weight
#4,429
vs
#4,581
1.2-280 leads by 152 places
Warranty
#21
vs
#21
Tied - the same position in the database
Overall
#9,828
vs
#1,760
2.1-635 leads by 8,068 places
05
Open the full database
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06
Written summary
Checking cache...
07
Questions about this pairing
Which panel is better: Heckert Solar ZEUS 1.2-280 or Heckert Solar ZEUS 2.1-635?
According to our database: Heckert Solar ZEUS 2.1-635 has higher module efficiency (23.50% vs 23.31%); Heckert Solar ZEUS 1.2-280 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 Heckert Solar ZEUS 1.2-280 and Heckert Solar ZEUS 2.1-635?
Heckert Solar ZEUS 1.2-280 has a module efficiency of 23.31%, while Heckert Solar ZEUS 2.1-635 is 23.50%. Higher efficiency means more electricity from the same roof area - useful when space is limited.
What cell technology does Heckert Solar ZEUS 1.2-280 use vs Heckert Solar ZEUS 2.1-635?
Heckert Solar ZEUS 1.2-280 uses Back Contact cells; Heckert Solar ZEUS 2.1-635 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 Heckert Solar ZEUS 1.2-280 and Heckert Solar ZEUS 2.1-635?
Heckert Solar ZEUS 1.2-280 has a 30 years power warranty; Heckert Solar ZEUS 2.1-635 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 Heckert Solar ZEUS 1.2-280 and Heckert Solar ZEUS 2.1-635 bifacial panels?
Both Heckert Solar ZEUS 1.2-280 and Heckert Solar ZEUS 2.1-635 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 16 Heckert 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.