When selecting solar wafers, the primary decision is between Monocrystalline (Mono-Si) and Polycrystalline (Multi-Si). For modern high-efficiency requirements, N-type Monocrystalline wafers are the industry standard due to their lower light-induced degradation (LID) and higher conversion efficiency compared to P-type. You must also specify the wafer size, such as M10 (182mm) or G12 (210mm), as these larger formats significantly reduce the Levelized Cost of Energy (LCOE) by increasing power output per module.