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Monofacial vs Bifacial 17 of 18 identical Swap Change panels

Tongwei TNC G12-66 Monofacial vs Tongwei TNC G12-66 Bifacial

TNC G12-66 Monofacial
710 Wp 22.90 % TOPCon
Open panel page Datasheet PDF
VS
TNC G12-66 Bifacial
705 Wp 22.70 % TOPCon
Open panel page Datasheet PDF
The verdict

Monofacial leads on the differences that matter

The largest is module efficiency: 0.20 pp more efficient. 17 of 18 comparable parameters are identical, with 1 more left out because at least one datasheet does not publish it.

See the one difference
How alike are they
17 of 18 comparable
parameters are identical
identical differs not published
01

What actually differs

1 of 18 parameters
Parameter Monofacial Bifacial Difference
Module efficiency 22.90 % 22.70 % 0.20 pp more efficient
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
Same temp coeff. for both panels (-0.280 %/°C), so a warmer roof scales both curves by the same factor: the totals fall together and neither panel gains on the other.
Monofacial
23,822 kWh
Bifacial
23,654 kWh
Lifetime gap
168 kWh
Output when it is hot
Rated power carried across the range a module actually sees
Scenario Monofacial Bifacial
Standard test conditions 25 °C 100.0% of rated power 710 W 705 W
Cool, bright day 40 °C 95.8% of rated power 680 W 675 W
Typical summer roof 55 °C 91.6% of rated power 650 W 646 W
Hot roof 70 °C 87.4% of rated power 621 W 616 W
03

Full specification

Parameter Monofacial Bifacial Difference
Power and efficiency
Rated power 710 Wp 705 Wp Effectively the same
Module efficiency 22.90 % 22.70 % +0.20 pp for Monofacial
Power density 228.6 Wp/m² 227.0 Wp/m² Effectively the same
Open-circuit voltage 48.94 V 48.77 V Effectively the same
Voltage at max power 40.69 V 40.52 V Effectively the same
Short-circuit current 18.45 A 18.40 A Effectively the same
Current at max power 17.45 A 17.40 A Effectively the same
Temperature
Temperature coefficient -0.280 %/°C -0.280 %/°C Same
Mechanical
Dimensions 2384x1303 mm 2384x1303 mm Same
Module area 3.106 m² 3.106 m² Same
Weight 37.9 kg 37.9 kg Same
Weight per kWp 53.4 kg/kWp 53.8 kg/kWp Effectively the same
Warranty and degradation
Product warranty 12 yrs 12 yrs Same
Performance warranty 30 yrs 30 yrs Same
Annual degradation 0.40 %/yr 0.40 %/yr Same
Technology
Cell technology TOPCon TOPCon Same
Cell type Monocrystalline Monocrystalline Same
Cell count - - Neither datasheet publishes this
Bifacial No No Same
04

Against the whole database

14,005 panels
Efficiency
#2,359 vs #3,307
Monofacial leads by 948 places
Power density
#2,474 vs #3,361
Monofacial leads by 887 places
Heat behaviour
#1,309 vs #1,309
Tied - the same position in the database
Weight
#7,271 vs #7,811
Monofacial leads by 540 places
Warranty
#21 vs #21
Tied - the same position in the database
Overall
#817 vs #1,007
Monofacial leads by 190 places
05

More useful comparisons

Open the full database
Same series, other bin
Tongwei TNC G12-66 Monofacial vs Tongwei THC G12-66 Bifacial
9 differences, the largest is module efficiency
Same series, other bin
Tongwei TNC G12-66 Monofacial vs Tongwei TWMNF-66HD
3 differences, the largest is product warranty
Same series, other bin
Tongwei TNC G12-66 Monofacial vs Tongwei TNC M10-78 Bifacial
9 differences, the largest is rated power
Same series, other bin
Tongwei TNC G12-66 Monofacial vs Tongwei TWMNH-66HS
10 differences, the largest is rated power
Same series, other bin
Tongwei TNC G12-66 Monofacial vs Tongwei TWMNH-66HD
9 differences, the largest is rated power
Same series, other bin
Tongwei TNC G12-66 Monofacial vs Tongwei TNC G12R-66 Monofacial
6 differences, the largest is rated power
06

Written summary

07

Questions about this pairing

Which panel is better: Tongwei TNC G12-66 Monofacial or Tongwei TNC G12-66 Bifacial?
According to our database: Tongwei TNC G12-66 Monofacial has higher module efficiency (22.90% vs 22.70%). See the full spec comparison and 30-year energy simulation above for a complete picture.
What is the efficiency of Tongwei TNC G12-66 Monofacial and Tongwei TNC G12-66 Bifacial?
Tongwei TNC G12-66 Monofacial has a module efficiency of 22.90%, while Tongwei TNC G12-66 Bifacial is 22.70%. Higher efficiency means more electricity from the same roof area - useful when space is limited.
What cell technology does Tongwei TNC G12-66 Monofacial use vs Tongwei TNC G12-66 Bifacial?
Tongwei TNC G12-66 Monofacial uses TOPCon cells; Tongwei TNC G12-66 Bifacial 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 Tongwei TNC G12-66 Monofacial and Tongwei TNC G12-66 Bifacial?
Tongwei TNC G12-66 Monofacial has a 30 years power warranty; Tongwei TNC G12-66 Bifacial 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.

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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.