1.2-275 vs 2.1 640W 5 of 19 identical Swap Change panels

Heckert Solar ZEUS 1.2-275 vs Heckert Solar ZEUS 2.1 640W

Q: Which panel is better: Heckert Solar ZEUS 1.2-275 or Heckert Solar ZEUS 2.1 640W?

According to our database: Heckert Solar ZEUS 2.1 640W has higher module efficiency (23.70% vs 22.89%); Heckert Solar ZEUS 1.2-275 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.

Q: What is the efficiency of Heckert Solar ZEUS 1.2-275 and Heckert Solar ZEUS 2.1 640W?

Heckert Solar ZEUS 1.2-275 has a module efficiency of 22.89%, while Heckert Solar ZEUS 2.1 640W is 23.70%. Higher efficiency means more electricity from the same roof area - useful when space is limited.

Q: What cell technology does Heckert Solar ZEUS 1.2-275 use vs Heckert Solar ZEUS 2.1 640W?

Heckert Solar ZEUS 1.2-275 uses Back Contact cells; Heckert Solar ZEUS 2.1 640W uses TOPCon. Modern n-type technologies (TOPCon, HJT, BC) typically deliver higher efficiency and lower degradation compared to older PERC (p-type) cells.

Q: What is the warranty on Heckert Solar ZEUS 1.2-275 and Heckert Solar ZEUS 2.1 640W?

Heckert Solar ZEUS 1.2-275 has a 30 years power warranty; Heckert Solar ZEUS 2.1 640W 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.

Q: Are Heckert Solar ZEUS 1.2-275 and Heckert Solar ZEUS 2.1 640W bifacial panels?

Both Heckert Solar ZEUS 1.2-275 and Heckert Solar ZEUS 2.1 640W 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.

Heckert Solar

ZEUS 1.2-275

275 Wp 22.89 % Back Contact Bifacial

Open panel page

Heckert Solar

ZEUS 2.1 640W

640 Wp 23.70 % TOPCon Bifacial

Open panel page

The verdict

14 differences, and they point both ways

The largest is module efficiency: 0.81 pp more efficient. 5 of 19 comparable parameters are identical.

See all 14 differences

How alike are they

5 of 19 comparable
parameters are identical

identical differs

What actually differs

14 of 19 parameters

Parameter 1.2-275 2.1 640W Difference

Module efficiency 22.89 % 23.70 % 0.81 pp more efficient

Rated power 275 Wp 640 Wp 365 W more power

Weight 14.3 kg 32.5 kg 18.2 kg lighter

Product warranty 30 yrs 12 yrs 18 yrs longer

Power density 228.9 Wp/m² 236.9 Wp/m² 8.0 Wp/m² higher

Temperature coefficient -0.260 %/°C -0.280 %/°C 0.020 %/°C better in heat

Open-circuit voltage 23.89 V 49.75 V 25.86 V apart

Module area 1.201 m² 2.701 m² 1.500 m² apart

Short-circuit current 14.65 A 16.33 A 1.68 A apart

Cell technology Back Contact TOPCon Back Contact vs TOPCon

Voltage at max power 20.36 V 41.38 V 21.02 V apart

Cell count 64 132 68 cells apart

Current at max power 13.51 A 15.47 A 1.96 A apart

Dimensions 1560x770x35 mm 2382x1134x30 mm 1560x770x35 mm vs 2382x1134x30 mm

What it means on a roof

Thirty years of production

Each panel's own declared degradation curve, at 1,200 kWh/kWp a year

Cell temperature

1.2-275

9,056 kWh

2.1 640W

21,076 kWh

Lifetime gap

12,020 kWh

Output when it is hot

Rated power carried across the range a module actually sees

Scenario 1.2-275 2.1 640W

Standard test conditions 25 °C 100.0% of rated power 275 W 640 W

Cool, bright day 40 °C 95.8% of rated power 264 W 613 W

Typical summer roof 55 °C 91.6% of rated power 254 W 586 W

Hot roof 70 °C 87.4% of rated power 243 W 559 W

Full specification

Parameter 1.2-275 2.1 640W Difference

Power and efficiency

Rated power 275 Wp 640 Wp +365 W for 2.1 640W

Module efficiency 22.89 % 23.70 % +0.81 pp for 2.1 640W

Power density 228.9 Wp/m² 236.9 Wp/m² +8.0 Wp/m² for 2.1 640W

Open-circuit voltage 23.89 V 49.75 V 25.86 V apart

Voltage at max power 20.36 V 41.38 V 21.02 V apart

Short-circuit current 14.65 A 16.33 A 1.68 A apart

Current at max power 13.51 A 15.47 A 1.96 A apart

Temperature

Temperature coefficient -0.260 %/°C -0.280 %/°C +0.020 %/°C for 1.2-275

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 1.2-275

Weight per kWp 52.0 kg/kWp 50.8 kg/kWp Effectively the same

Warranty and degradation

Product warranty 30 yrs 12 yrs +18 yrs for 1.2-275

Performance warranty 30 yrs 30 yrs Same

Annual degradation 0.45 %/yr 0.45 %/yr Same

Technology

Cell technology Back Contact TOPCon Back Contact vs TOPCon

Cell type Monocrystalline Monocrystalline Same

Cell count 64 132 68 cells apart

Bifacial Yes Yes Same

Against the whole database

13,953 panels

Efficiency

#2,490 vs #511

2.1 640W leads by 1,979 places

Power density

#2,404 vs #515

2.1 640W leads by 1,889 places

Heat behaviour

#511 vs #1,290

1.2-275 leads by 779 places

Weight

#5,386 vs #4,174

2.1 640W leads by 1,212 places

Warranty

#21 vs #21

Tied - the same position in the database

Overall

#10,137 vs #1,515

2.1 640W leads by 8,622 places

More useful comparisons

Open the full database

Same series, other bin

Heckert Solar

Heckert Solar ZEUS 1.2-275 vs Heckert Solar ZEUS 2.1-640

14 differences, the largest is module efficiency

Same series, other bin

Heckert Solar

Heckert Solar ZEUS 1.2-275 vs Heckert Solar ZEUS 2.1-635

14 differences, the largest is rated power

Same series, other bin

Heckert Solar

Heckert Solar ZEUS 1.2-275 vs Heckert Solar ZEUS 2.1 635W

14 differences, the largest is rated power

Same series, other bin

Heckert Solar

Heckert Solar ZEUS 1.2-275 vs Heckert Solar ZEUS 1.2 FullBlack 280W

2 differences, the largest is module efficiency

Same series, other bin

Heckert Solar

Heckert Solar ZEUS 1.2-275 vs Heckert Solar ZEUS 1.2-280

2 differences, the largest is module efficiency

Same series, other bin

Heckert Solar

Heckert Solar ZEUS 1.2-275 vs Heckert Solar ZEUS 1.2 FullBlack 275W

The same specification on paper

Written summary

Checking cache...

Questions about this pairing

Which panel is better: Heckert Solar ZEUS 1.2-275 or Heckert Solar ZEUS 2.1 640W?

According to our database: Heckert Solar ZEUS 2.1 640 W has higher module efficiency (23.70% vs 22.89%); Heckert Solar ZEUS 1.2-275 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 1.2-275 and Heckert Solar ZEUS 2.1 640W?

Heckert Solar ZEUS 1.2-275 has a module efficiency of 22.89%, while Heckert Solar ZEUS 2.1 640 W is 23.70%. Higher efficiency means more electricity from the same roof area - useful when space is limited.

What cell technology does Heckert Solar ZEUS 1.2-275 use vs Heckert Solar ZEUS 2.1 640W?

Heckert Solar ZEUS 1.2-275 uses Back Contact cells; Heckert Solar ZEUS 2.1 640 W uses TOPCon. 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 1.2-275 and Heckert Solar ZEUS 2.1 640W?

Heckert Solar ZEUS 1.2-275 has a 30 years power warranty; Heckert Solar ZEUS 2.1 640 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 1.2-275 and Heckert Solar ZEUS 2.1 640W bifacial panels?

Both Heckert Solar ZEUS 1.2-275 and Heckert Solar ZEUS 2.1 640 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.

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.