Putting this into perspective, a solar cell architecture of 19.95% efficiency using the M2 wafer format will show a 0.1 W power gain compared to M0. Therefore, larger ingot sizes allow for monocrystalline wafers to be less “pseudo” square, increasing the resulting wafer size and hence the amount of light that could be captured.
Before 2010, monocrystalline silicon wafers were dominated by 125mm x 125mm width (165mm silicon ingot diameter) and only a small number at 156mm x 156mm (200mm silicon ingot diameter). After 2010, 156mm x 156mm wafers increasingly became the popular choice (lower cost per-watt) for p-Type monocrystalline and multicrystalline wafer sizes.
During that period of 2013, there were also a few M4 (161.7mm x 161.6mm) (211mm diameter silicon ingot) wafers on the market. In 2016, the move from 156mm x 156mm to the larger formats of 156.75mm x 156.75mm in mass production began.
The user selects (i) the shape and dimensions of a wafer, (ii) the wafer material (e.g., Si, GaAs), and (iii) the conversion efficiency at a particular incident illumination intensity. The wafer calculator then calculates (i) the area and volume of the wafer, (ii) the mass of the wafer, and (iii) the output power and power per gram.
However, silicon's abundance, and its domination of the semiconductor manufacturing industry has made it difficult for other materials to compete. An optimum silicon solar cell with light trapping and very good surface passivation is about 100 µm thick.
Wafer thickness, a pivotal design parameter that accounts for up to 50% of current solar cell material costs 49 and used by the PV industry to sustain silicon solar cells economically viable, 50 demonstrates significant dependency on location.