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1.2 FullBlack 280W vs 2.1-635 7 of 19 identical Swap Change panels

Heckert Solar ZEUS 1.2 FullBlack 280W vs Heckert Solar ZEUS 2.1-635

Heckert Solar
ZEUS 1.2 FullBlack 280W
280 Wp 23.31 % Back Contact Bifacial
Open panel page Datasheet PDF
VS
Heckert Solar
ZEUS 2.1-635
635 Wp 23.50 % N-type Bifacial
Open panel page Datasheet PDF
The verdict

1.2 FullBlack 280W 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 differences
How alike are they
7 of 19 comparable
parameters are identical
identical differs
01

What actually differs

12 of 19 parameters
Parameter 1.2 FullBlack 280W 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 FullBlack 280W
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 FullBlack 280W 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 FullBlack 280W 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 FullBlack 280W
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 FullBlack 280W
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 FullBlack 280W
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

Against the whole database

14,129 panels
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 FullBlack 280W leads by 832 places
Weight
#4,429 vs #4,581
1.2 FullBlack 280W 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

More useful comparisons

Open the full database
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Heckert Solar ZEUS 1.2 FullBlack 280W vs Heckert Solar ZEUS 1.2 FullBlack 275W
2 differences, the largest is module efficiency
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Heckert Solar ZEUS 1.2 FullBlack 280W vs Heckert Solar ZEUS 1.2 FullBlack 270W
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Heckert Solar ZEUS 2.1-635 vs Heckert Solar ZEUS 2.1-640
One difference: module efficiency
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Heckert Solar ZEUS 2.1-635 vs Heckert Solar ZEUS 2.1 640W
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Heckert Solar ZEUS 2.1-635 vs Heckert Solar ZEUS 2.1 635W
One difference: cell technology
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Heckert Solar ZEUS 2.1-635 vs Heckert Solar ZEUS 1.2-280
12 differences, the largest is rated power
06

Written summary

07

Questions about this pairing

Which panel is better: Heckert Solar ZEUS 1.2 FullBlack 280W 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 FullBlack 280 W 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 FullBlack 280W and Heckert Solar ZEUS 2.1-635?
Heckert Solar ZEUS 1.2 FullBlack 280 W 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 FullBlack 280W use vs Heckert Solar ZEUS 2.1-635?
Heckert Solar ZEUS 1.2 FullBlack 280 W 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 FullBlack 280W and Heckert Solar ZEUS 2.1-635?
Heckert Solar ZEUS 1.2 FullBlack 280 W 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 FullBlack 280W and Heckert Solar ZEUS 2.1-635 bifacial panels?
Both Heckert Solar ZEUS 1.2 FullBlack 280 W 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.

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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.