It’s not often that one looks at the early years of the solar industry with nostalgia, but it was at least a time that had some consistency in solar panel sizes. It was generally understood that 60-cell solar panels were made for the residential market, while 72-cell panels were used in commercial and utility-scale applications. The larger solar panels had two extra rows of cells, making them longer and more powerful for bigger projects.

Now, the global market has moved to larger cell sizes, which has in turn increased the size of solar panels. That wouldn’t be an issue if each company used the same-size cell, but the industry has split into two main cell-size camps that lead to inconsistencies in final module sizes — one company’s 72-cell panel is not the same size as another’s if cell sizes differ by 30 millimeters.

The two new main wafer sizes that have dominated the market are the M10 (182-mm) and G12 (210-mm). LONGi Solar is the leading M10 wafer supplier, and JinkoSolar, JA Solar and Qcells have signed on to the 182-mm camp. Chinese silicon wafer supplier Zhonghuan Semiconductor is championing the larger G12 size, and supporters of the 210-mm wafer include Trina Solar, REC and Maxeon.

The industry’s new sizes are influencing how panel companies market their models, said Thomas Koerner, corporate VP of global sales for modules with Canadian Solar, a manufacturer that is using both of the larger wafer sizes.

“Our naming convention has moved away from using terms like ‘72-cell panels.’ We refer to them by power class,” he said. “Our customers use the power class and size/efficiency when ordering.”

While no longer confined to standard sizing, companies do still follow certain guidelines. For example, solar panels used primarily in the residential market are influenced by labor and weight limitations in the United States, Koerner noted. But customers make the final decision on the optimal type of solar panel for each project.

“We are agnostic with our residential and utility-scale modules. If residential customers want to use larger-format modules, we are technically capable to design and make [them] available,” Koerner said. “We define our sizes to work best for our customers for optimum power, efficiency and reliability.”

The International Technology Roadmap for Photovoltaic (ITRPV) report already shows the larger M10 and G12 wafers holding over 50% of the market and expects the two largest wafers to be the only size options by 2032, with, of course, the opportunity to go even bigger.

Although product names and dimensions are changing, software makes designing projects easy for installers turning to bigger solar panels. Aurora Solar’s 3D layout tool can handle any-size module, and CEO Chris Hopper said the company pulls module dimensions and electrical specifications from data sheets throughout the year. The software handles the rest.

“Installers can take advantage of the global component libraries in both Aurora and HelioScope, where several thousand (1,700 and 2,400, respectively) modules have been added in the last year alone,” he said. “There’s no need to manually import dozens of parameters, and if we don’t have the module in our database, our teams will add it for you.”

Bigger modules are here to stay, and industry players are making the transition simple for installation crews.

---

This story is part of SPW’s 2023 Trends in Solar. Read all of this year’s trends here.