The solar PV industry demands more power with a lower cost per watt, can larger wafers deliver the goods?
Manufacturers are leaving behind the older ‘M2’ standard wafer size of 156.75 mm² in a bid to meet the industry’s demands for increased power output.
While making wafers bigger might seem like a simple way to increase power output, it can cause problems downstream when it comes to installation practices and racking design.
Yet the size of silicon wafers has crept up slowly over the past decade from 125 mm² (before 2010) then a big jump to 156 mm² which became the standard until 2014 when the M2 wafer was introduced and which represented more than 90% of the market in 2018.
2019 has seen several manufacturers up their wafer game to a new standard – 158.75 mm², of which JinkoSolar is one.
While JinkoSolar state that they have the ability to make bigger wafers, they say, “this currently represents the best compromise
between manufacturing processes and PV module features”. The new module series Cheetah have 158.75 mm² wafers.
JA Solar have also opted for a 158.75 mm² wafer for 2019 which gives their modules 2% more yield with only a small size difference to the module’s dimensions.
Want to supersize that?
Some wafer suppliers are taking it further with the M4 format at 161.75 mm², while another launched a 166 mm² M6 wafer. The biggest reported wafer size is a gargantuan 210 mm²!
So back to the question, does size matter? Well, at present, it seems like there is no right answer even though theories on optimum size are gaining ground. Watch this space…