Front-side power generation represents the core capability

while back-side power generation offers added value

The Secret Behind TNC 2.0's Dual-Sided Power Generation

Photovoltaic (PV) modules exhibit a duality

The commonly cited module power refers to the nameplate power

representing the front-side power generation capacity, akin to the two sides of a coin

Modules also have two sides, and in practical applications

the back side is also contributing to energy production

Crucially, module prices are determined based on front-side power

The electricity generated from the back side can be considered an added benefit

How significant is this "free lunch"?

The TNC 2.0 module offers insights

01

Standardization is Key!

IEC Sets the Rules for Back-Side Power Generation

In 2021

the IEC 61215, an authoritative standard in the photovoltaic field

made a significant advancement

by formally incorporating "Bifacial Nameplate Irradiance (BNPI)"

This provides a reliable standard for

scientifically evaluating the power output of bifacial modules

What is BNPI?

In essence, it refers to the electrical performance under the conditions of

1000 W/㎡ irradiance on the front side

and 135 W/㎡ irradiance

on the back side

Other environmental conditions and standard test conditions (STC) remain consistent

This represents the average environmental reflected light intensity received

on the back side of the module when it is 1 meter above the ground

approximately 13.5% of the front-side irradiance

The power measured under this "typical" back-side light intensity

is already reflected in the product nameplates of certain manufacturers

For certain extreme high-reflection scenarios

IEC 61215:2021 also provides corresponding

test standards—Bifacial Reliability Irradiance (BSI)

Under this standard's test conditions

the front maintains 1000W/m² irradiance

while back-side irradiance increases to 300W/m²

equivalent to 30% of the front side

Other test conditions are consistent with STC

This simulates the extreme conditions of back-side irradiance

that may be achieved in various application scenarios

Key takeaways:

Back-side power generation gain, under standard evaluation (BPNI)

contributes approximately the equivalent of 13.5% of front-side irradiance

Under extreme reliability testing (BSI)

the back-side contribution can reach the equivalent of 30% of front-side irradiance

The IEC standard provides a reliable basis

for the value assessment of bifacial modules

02

Calculating the Benefits

TNC 2.0's Gain is Visible

With the theory understood, how much actual gain is there?

Let's examine the flagship product of Tongwei TNC 2.0!

Based on the IEC BNPI standard, the gain is calculated as:

Back-side equivalent gain = standard back-side irradiance ratio x bifaciality

According to an analysis by Infolink

In 2024, the market share of N-type dual-glass modules will reach over 80%

It is estimated that from 2025-2028, the market share of dual-glass modules

will further grow to over 85%

This means that

the high bifaciality advantage of TNC 2.0 modules

along with the resulting high gains

will be widely applied in most scenarios globally

03

Higher Bifaciality

Amplifying the Value of Solar Energy

Bifacial power generation is not just a gimmick

The IEC standard allows the value of this "environmental gift"

to be scientifically measured

Tongwei TNC 2.0 technology

precisely captures and amplifies this value

Recently, Tongwei Global Innovation R&D Center showcased its latest technological breakthrough:

ultra-high bifaciality modules based on

Tunnel Oxide Passivated Contact (TOPCon) technology

achieving a cell bifaciality of

94.3%

while module bifaciality reaching

91.7%

(Certified by TÜV Rheinland)

"Tongwei has begun trial production of modules with over 90% bifaciality and plans to launch large-scale production of modules with over 85% bifaciality this year. It is expected that the mass production technology goals of cell bifaciality reaching 95%

and module bifaciality reaching 90% may be achieved in the next 1-2 years."

—Meng Xiajie, Director of the Cell Development Department of the PV Technology Center of Tongwei

Choosing Tongwei TNC 2.0 means

Choosing a visible "extra benefit"

With solid front-side power, robust back-side gain

superior overall power, better "investment returns"

higher power generation, and lower levelized cost of electricity

TNC 2.0, with its innovative technology

delivers this "double surprise" from the sun

contributing to a more efficient and sustainable green energy future

Planned and produced by: Module Marketing Division of PV Business Department, and the Administrative Department

Content support: PV Technology Department, Product Management Division of PV Business Department