As explained in our previous article Efficiency Trends And Technology Shifts In TOP SOLAR MODULES, efficiency has been the key parameter of this analysis. With the TOP SOLAR MODULES list having grown to 50+ products over the 2 years, it is both difficult to present and consume all the data. So to make the analysis a little easier on both these fronts, we split them into 4 efficiency bands: >22.5%, >22% to 22.5%, >21.7%to 22%, and 21.5% to 21.7%.Starting off with numerical data, the graph above provides a 2-year overview of the efficiency development of the different products listed in TOP SOLAR MODULES categorized into the 4 efficiency bands described above. The highest efficiency band, i.e., ‘>22.5%’, has more or less doubled its share, growing from a 15% level in January 2023 to 28% in December 2024. It also means that more and more products with efficiencies greater than 22.5% are hitting the commercial space, which also reflects market trends (see Top Efficiency Of Each Cell Technology). Interestingly, the development progress in the next band – >22% to 22.5% – has been inversely proportional to the one above it. Starting at a 24% share in January, this band hit a peak of 39% in mid-2023, in August to be precise, and then began its slow decline to a level of 30% at the end of 2024. This is the band that products from many companies started out with. But as these companies adopted advanced technologies like TOPCon and HJT and eventually gained expertise, they improved their efficiency levels and started commercializing modules with much higher efficiencies, a few even beyond 22.5%. This phenomenon explains the fall in the ‘>22% to 22.5%’ efficiency band and the rise in the band above, especially toward the end of 2023 and all along 2024.The third band – >21.7% to 22% – had the lowest representation with a share of 9% in January 2023. Having hit a bottom of 2% by July-August, it saw a slight recovery to 4% in September, where it remained for the rest of 2023 and throughout 2024. While this group’s 21.7% minimum is already too high for PERC, the 22% upper limit is not high enough for advanced technologies, which explains the low representation for this group. This band is also just a quick stopover for products based on advanced technologies before they move on to the next level, and those that do remain in this group are often not the core focus of their companies. Accounting for the bulk of the listing, the entry-level band of 21.5% to 21.7% is mostly represented by PERC, while one HJT module was also part of it until August 2023. This band’s share has dropped consistently from 53% in 2023 to 38% by the end of 2024. The decline in 2023 was mainly due to an increasing number of companies adopting advanced cell architectures, commercializing respective products with higher efficiencies, and moving out of this band as a result. With no new companies entering this band, its share plateaued for the first half of 2024 and declined considerably in the second half. This decline in the latter part of the year corresponded with the delisting of 5 products as their production stopped and were taken off the market (see Tracking Efficiency Improvements In Solar Modules).
