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

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

Heckert Solar
ZEUS 2.1-635
635 Wp 23.50 % N-type Bifacial
Open panel page Datasheet PDF
VS
Heckert Solar
ZEUS 1.2 FullBlack 280W
280 Wp 23.31 % Back Contact 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 2.1-635 1.2 FullBlack 280W Difference
Rated power 635 Wp 280 Wp 355 W more power
Weight 32.5 kg 14.3 kg 18.2 kg lighter
Product warranty 12 yrs 30 yrs 18 yrs longer
Temperature coefficient -0.280 %/°C -0.260 %/°C 0.020 %/°C better in heat
Open-circuit voltage 49.60 V 24.11 V 25.49 V apart
Module area 2.701 m² 1.201 m² 1.500 m² apart
Short-circuit current 16.26 A 14.72 A 1.54 A apart
Cell technology N-type Back Contact N-type vs Back Contact
Voltage at max power 41.24 V 20.49 V 20.75 V apart
Cell count 132 64 68 cells apart
Current at max power 15.40 A 13.67 A 1.73 A apart
Dimensions 2382x1134x30 mm 1560x770x35 mm 2382x1134x30 mm vs 1560x770x35 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
2.1-635
20,911 kWh
1.2 FullBlack 280W
9,221 kWh
Lifetime gap
11,690 kWh
Output when it is hot
Rated power carried across the range a module actually sees
Scenario 2.1-635 1.2 FullBlack 280W
Standard test conditions 25 °C 100.0% of rated power 635 W 280 W
Cool, bright day 40 °C 95.8% of rated power 608 W 269 W
Typical summer roof 55 °C 91.6% of rated power 582 W 258 W
Hot roof 70 °C 87.4% of rated power 555 W 247 W
03

Full specification

Parameter 2.1-635 1.2 FullBlack 280W Difference
Power and efficiency
Rated power 635 Wp 280 Wp +355 W for 2.1-635
Module efficiency 23.50 % 23.31 % Effectively the same
Power density 235.1 Wp/m² 233.1 Wp/m² Effectively the same
Open-circuit voltage 49.60 V 24.11 V 25.49 V apart
Voltage at max power 41.24 V 20.49 V 20.75 V apart
Short-circuit current 16.26 A 14.72 A 1.54 A apart
Current at max power 15.40 A 13.67 A 1.73 A apart
Temperature
Temperature coefficient -0.280 %/°C -0.260 %/°C +0.020 %/°C for 1.2 FullBlack 280W
Mechanical
Dimensions 2382x1134x30 mm 1560x770x35 mm 2382x1134x30 mm vs 1560x770x35 mm
Module area 2.701 m² 1.201 m² 1.500 m² apart
Weight 32.5 kg 14.3 kg -18.2 kg for 1.2 FullBlack 280W
Weight per kWp 51.2 kg/kWp 51.1 kg/kWp Effectively the same
Warranty and degradation
Product warranty 12 yrs 30 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 N-type Back Contact N-type vs Back Contact
Cell type Monocrystalline Monocrystalline Same
Cell count 132 64 68 cells apart
Bifacial Yes Yes Same
04

Against the whole database

14,129 panels
Efficiency
#749 vs #1,055
2.1-635 leads by 306 places
Power density
#777 vs #1,136
2.1-635 leads by 359 places
Heat behaviour
#1,347 vs #515
1.2 FullBlack 280W leads by 832 places
Weight
#4,581 vs #4,429
1.2 FullBlack 280W leads by 152 places
Warranty
#21 vs #21
Tied - the same position in the database
Overall
#1,760 vs #9,828
2.1-635 leads by 8,068 places
05

More useful comparisons

Open the full database
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06

Written summary

07

Questions about this pairing

Which panel is better: Heckert Solar ZEUS 2.1-635 or Heckert Solar ZEUS 1.2 FullBlack 280W?
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 2.1-635 and Heckert Solar ZEUS 1.2 FullBlack 280W?
Heckert Solar ZEUS 2.1-635 has a module efficiency of 23.50%, while Heckert Solar ZEUS 1.2 FullBlack 280 W is 23.31%. Higher efficiency means more electricity from the same roof area - useful when space is limited.
What cell technology does Heckert Solar ZEUS 2.1-635 use vs Heckert Solar ZEUS 1.2 FullBlack 280W?
Heckert Solar ZEUS 2.1-635 uses N-type cells; Heckert Solar ZEUS 1.2 FullBlack 280 W 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 Heckert Solar ZEUS 2.1-635 and Heckert Solar ZEUS 1.2 FullBlack 280W?
Heckert Solar ZEUS 2.1-635 has a 30 years power warranty; Heckert Solar ZEUS 1.2 FullBlack 280 W 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 2.1-635 and Heckert Solar ZEUS 1.2 FullBlack 280W bifacial panels?
Both Heckert Solar ZEUS 2.1-635 and Heckert Solar ZEUS 1.2 FullBlack 280 W 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.