In late May, following the release of 2025 operational data from SPIC’s Daqing Demonstration Site, discussions regarding the TOPCon and BC technology routes have heated up once again. Based on results from Phases I through III, TOPCon has consistently maintained a lead in power generation: Phase I saw a 1.25% increase in power generation per watt compared to IBC, and Phase III still led by 0.75%. More importantly, over several years of operation, TOPCon’s lead has not narrowed.
From Bifaciality to Low-Light Performance: Where Does TOPCon’s Power Generation Advantage Come From?
Industry discussions on TOPCon versus the BC route often focus on laboratory metrics such as conversion efficiency. However, for power plant investors, it is the total power generation over the full lifecycle that ultimately determines returns.
According to data from SPIC’s Daqing Demonstration Base, one of the key reasons TOPCon maintains higher power generation over the long term is its superior bifacial power generation capability. Demonstration data shows that the bifaciality of TOPCon modules has long remained in the 77%–80% range, significantly higher than the approximately 72% level of IBC modules. In scenarios with highly reflective ground surfaces, higher bifaciality means more light can be captured from the rear side, thereby translating into additional power generation benefits. Based on measurements from the Daqing site, the difference in bifaciality alone can yield an output power gain of over 2%.
However, bifaciality alone does not fully explain why TOPCon offers superior power generation. The true factor driving the difference in power output lies in the ability of different technological approaches to utilize spectral resources. After sunlight passes through the atmosphere, some short-wavelength light is absorbed and scattered, while during low-irradiance periods—such as early morning, evening, and overcast conditions—a higher proportion of long-wavelength light reaches the ground. TOPCon possesses inherent advantages in utilizing long-wavelength light and responding to low-light conditions, enabling it to maintain higher output levels under low-irradiance conditions. This explains why, in multiple demonstration projects in Daqing and Wuwei, Gansu, among others, TOPCon systems generally exhibit a “start early, finish late” power generation pattern, thereby achieving longer effective generation periods.
For today’s electricity market, the importance of this capability is steadily increasing. As renewable energy fully participates in market-based trading, where electricity prices are often higher during morning and evening hours, the advantage of power generation under low-light conditions is gradually translating into higher returns for power plants.
TOPCon Demonstrates Even Greater Advantages Under Complex Operating Conditions
In addition to bifaciality and low-light performance, adaptability under complex operating conditions is another key reason for TOPCon’s continued leadership. TOPCon inherently employs a structure with separate anodes and cathodes, resulting in lower leakage current losses compared to back-contact designs. This allows it to maintain more stable output performance in high-temperature, high-humidity, and complex environments.
At the same time, TOPCon modules such as Jinko Solar’s Tiger Neo 3. 0 utilize a multi-segment design, offering superior shading tolerance and hot-spot control in shaded conditions. Even when parts of the module are partially shaded, it can maintain high power output, thereby minimizing power generation losses.
While these advantages may not be immediately apparent in laboratory tests, they accumulate over the long term and ultimately translate into higher power generation and better system returns. It is precisely for this reason that TOPCon has consistently maintained a leading position in demonstration projects such as those in Daqing and Wuwei.
Beyond Power Generation Leadership, TOPCon Continues to Evolve
The significance of the Daqing demonstration data lies not merely in proving TOPCon’s current leadership, but in validating that this technology path still possesses the capacity for continuous evolution.
During this year’s SNEC, JinkoSolar launched its next-generation Tiger Neo 5.0 module, with power output exceeding 700W. Through multi-dimensional innovations in wafers, cell structures, passivation processes, and encapsulation technology, the new product further unlocks the potential of TOPCon technology. According to calculations, it maintains a power generation advantage over the BC route in utility-scale, commercial and industrial, and residential applications.
If TOPCon has already made the leap from technological breakthrough to large-scale application in recent years, the data continuously accumulated by national-level demonstration platforms is illustrating another point: TOPCon is not only moving fast but also continuing to evolve. As more long-term operational data is released, discussions regarding different technological routes may increasingly return to the simplest criterion—which technology can generate greater real returns for power plants