A one-month carport field test experiment had been conducted, comparing the performance under different daytime durations of TOPCon and N-type BC solar modules in Lebanon. They assessed the outdoor panel to evaluate energy yield across the day and month, providing critical insights into their real-world energy yield under different irradiance as well as material-level reliability.
Highlights
- During the summer season from July 29 to August 31, the specific yield of TOPCon modules was 2.78% higher than that of BC modules on average.
- Under the dual influence of low irradiance in early morning and later afternoon, and high ambient temperature, the yield gain of TOPCon is a 7.08% increase in 7 am–8 am and 7.96% in 5 pm–6 pm in specific yield compared to BC modules.
- The vacant duration of carport during 12 pm–1 pm, the higher bifacial factor advantage of TOPCon contributes greatly to the high productivity of 4.62% specific yield over BC modules.
The experiment group included eight pieces of TOPCon bifacial modules (630 Wp) and eight pieces of N-type BC bifacial panels (640 Wp), both from tier-1 manufacturers. The modules were installed in two carports, with each connected to an inverter operated at maximum power point tracking (MPPT). The testing field was located in Mkalles, Lebanon (33.8623190 N, 35.5508300 E), with a carport near-flat tilt of 5 degrees, facing southeast, and with about 2.5 meters above the ground.
| Cell Technology | Module Power | Module Type |
|---|---|---|
| Jinko TOPCon | 630 W | Bifacial Dual-Glass |
| N-type BC | 640 W | Bifacial Dual-Glass |
All modules were equipped with high-precision sensors to monitor power generation data in real time to ensure the accuracy and credibility of the test results. During the test, a number of key data were collected at an interval of 6 minutes, including DC voltage, current, power, module temperature, and front irradiance. These data provided detailed information, allowing us to conduct in-depth analysis and comparison of the performance of the modules.
Test Results
Some significant irradiance and performance changes were observed in initial days from July 29 to August 31, 2025. The daily average irradiance recorded was 455.9 W/m², and the ambient temperature recorded was 30.22°C. The most observed irradiance range was 100–200 W/m², occurring in 7 am–8 am and 5 pm–6 pm, which in turn affected the power generation of the modules.
Under such conditions, the power generation of TOPCon modules was 141.07 kWh/kW, versus BC of 137.26 kWh/kW, 2.78% higher than that of BC modules. However, with the arrival of low irradiance and high temperature, TOPCon modules showed excellent performance, with a 7.08% increase in 7 am–8 am early morning and 7.96% in the later afternoon 5 pm–6 pm in power generation compared to BC modules. Another peak yield gain was observed of 4.62% during 12 pm–1 pm, which is lunchtime, when most cars parked underneath are driven out, leaving the carport less occupied and the effect of ground reflection maximized. This significant gain not only proves the high yield of TOPCon modules in low-light environments but also highlights their high bifaciality and high efficiency under high temperature.
Jinko TOPCon VS Other :Per WattGeneration Comparison
Jinko TOPCon VS OtherBC :Per Watt GenerationComparison(Days)
| Date TOPCon generationper watt N-typeBC generationper watt Per Watt Gain | |||
| 2025/7/29 | 5.11047619 | 4.954980469 | 3.14% |
| 2025/7/30 | 4.548948413 | 4.482480469 | 1.48% |
| 2025/7/31 | 4.179206349 | 4.056425781 | 3.03% |
| 2025/8/1 | 5.32202381 | 5.163261719 | 3.07% |
| 2025/8/2 | 0.90468254 | 0.859824219 | 5.22% |
| 2025/8/3 | 1.156507937 | 1.119550781 | 3.30% |
| 2025/8/4 | 3.310019841 | 3.151914063 | 5.02% |
| 2025/8/5 | 7.266071429 | 6.905078125 | 5.23% |
| 2025/8/6 | 6.548293651 | 6.278183594 | 4.30% |
| 2025/8/7 | 6.697380952 | 6.356210938 | 5.37% |
| 2025/8/8 | 6.665952381 | 6.463769531 | 3.13% |
| 2025/8/9 | 3.004801587 | 2.858398438 | 5.12% |
| 2025/8/10 | 0.853035714 | 0.772421875 | 10.44% |
| 2025/8/11 | 6.344980159 | 6.190175781 | 2.50% |
| 2025/8/12 | 6.105218254 | 6.049257813 | 0.93% |
| 2025/8/13 | 5.795714286 | 5.685898438 | 1.93% |
| 2025/8/14 | 6.300119048 | 6.222070313 | 1.25% |
| 2025/8/15 | 1.916349206 | 1.886953125 | 1.56% |
| 2025/8/16 | 1.563730159 | 1.506835938 | 3.78% |
| 2025/8/17 | 1.045357143 | 1.023164063 | 2.17% |
| 2025/8/18 | 6.212003968 | 6.051621094 | 2.65% |
| 2025/8/19 | 7.152083333 | 7.033671875 | 1.68% |
| 2025/8/20 | 6.526765873 | 6.446308594 | 1.25% |
| 2025/8/21 | 6.202361111 | 6.0559375 | 2.42% |
| 2025/8/22 | 3.587718254 | 3.410039063 | 5.21% |
| 2025/8/25 | 4.910555556 | 4.818730469 | 1.91% |
| 2025/8/26 | 5.776170635 | 5.693476563 | 1.45% |
| 2025/8/27 | 3.593492063 | 3.563164063 | 0.85% |
| 2025/8/28 | 5.416984127 | 5.330761719 | 1.62% |
| 2025/8/29 | 3.648214286 | 3.5771875 | 1.99% |
| 2025/8/30 | 0.274623016 | 0.269882813 | 1.76% |
| 2025/8/31                                                                                                    3.130611669                 3.023640253      3.54% Total                                                                  141.0704529                                                    137.261277                2.78% | |||
Conclusion
This comparison test, characterized by monitoring and tracing the generation changes of N-type TOPCon and N-type BC modules across the daytime, low and high irradiance, elevated temperatures, intense and unintended ground reflection, provides an ideal environment to gain critical insights into their real-world energy yield, irradiance response mechanism, yield gain contribution factor, and material-level reliability.
TOPCon modules, thanks to their superior low-light performance, high bifaciality, and favorable temperature coefficients, exhibited a yield gain of up to 4.62% at noon, 7.08% in the early morning, 7.96% in the later afternoon, and an average 2.78% higher kWh per kW compared to BC modules.
The test is still ongoing and will release more data soon.
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