DAS Solar Topcon Product Updates

• DAS Solar with main focus on TOPCon, has achieved 25.3% production efficiency and 26.4% R&D efficiency
• DAS Solar is mainly promoting 3 modules of the DAON series: the DAON Mini, the DAON C&I modules, and the DAON Pro, which are built with 108, 144, or 156 cells of M10 size, respectively
• DAS Solar also has a future technology roadmap to extend the TOPCon technology platform to IBC between 2024 and 2025.

DAS Solar, though a young company in PV manufacturing, has experience with TOPCon that is at par with any leading company in the segment, if not higher. Since its inception in 2018, DAS Solar has focused exclusively on TOPCon technology. At the TaiyangNews conference, Leo Chang, technical director at DAS Solar, presented the company's new developments for its n-type product range (see recording here).

Talking about the cell technology, Chang said that DAS Solar is running the TOPCon 3.0 technology generation. The key features of this technology are rear field passivation, which offers excellent passivation effect to decrease electron-hole pair recombination significantly, improving all the electrical characteristics – Voc, Jsc and FF. The company also uses graded refractive index multilayer film coating on the front side of the cell, which provides better passivation, lowers reflection, enhances anti-PID capability, and prevents color variation during encapsulation to ensure color uniformity at the module level, which is well appreciated in rooftop applications. DAS Solar has achieved a production efficiency of 25.3%, while its best certified R&D efficiency is at 26.4%, which is also based on TOPCon 3.0 and is currently used in mass production.

DAS Solar is mainly promoting 3 modules of the DAON series: the DAON Mini, the DAON C&I modules, and the DAON Pro. The DAON Mini is designed for residential applications and has a power rating of 420 to 440 W and up to 22.5% efficiency. The C&I modules with an efficiency of up to 22.6% have a power rating of 565 to 585 W. The DAON Pro is designed for utility applications and has a power rating of 615 to 640 W and the series is represented with the highest efficiency of 22.9% among the company's product range. All of these modules are built with 108, 144, or 156 cells of M10 size, respectively.

Chang quantified the benefits of TOPCon over PERC in terms of estimated power gain. The bifaciality of 80%, which is 10% higher than PERC, leads to a 2% gain. The DAON module family comes with a power warranty that guarantees degradation of no more than 1% in the first year and 0.4% for the rest of the 29 years. This is expected to result in 1.73% higher power generation. The low temperature coefficient of 0.3%/°C improves the power yield by 0.85%. DAS Solar has conducted field tests on the operating temperature of its n-type and p-type modules, which showed that its DAON series TOPCon modules have a 2.5 °C lower temperature than the p-type products. The better low-light response of the technology brings in a 0.5% gain. All of these advantages collectively result in up to 5% gain in power generation, according to Chang.

Even though the cost of the n-type modules is higher than the p-type, the lower BOS costs and higher energy yield result in a lower LCOE of 2.37%. A price difference of 0.03 CNY/W (higher) is factored in for this estimation. Chang also presented the realtime comparison of n-type and p-type modules at a project in Qinghai, China for a period from January 2021 to July 2022. The energy yield for DAON n-type modules showed 6.8% and 8.54% higher energy yield at different arrays, exceeding the theoretical expected gain.

As for the future development plans, Change mphasized that the current mass production efficiency of 25.3% is achieved with 130 μm wafers and expects to reduce the wafer thickness to 100 μm in the future. The company has a cell efficiency roadmap to increase the efficiency of its TOPCon cell technology to 26.2% by 2025. In parallel, DAS Solar also has a future technology roadmap to extend the TOPCon technology platform to IBC between 2024 and 2025, and then ultimately to perovskite tandem cells between 2025 and 2026, with efficiencies of up to 27% and 30%, respectively.

The text is an excerpt from TaiyangNews New Solar Products Overview H1/2023, which can be downloaded for free here.