Half-cut cells, PERCs and monos – solar cells are becoming more and more powerful and cost-effective. A current mega-trend is the advance of monocrystalline cells and modules which have scored higher levels of efficiency than polycrystalline technology.
While particularly highly performing solar modules with monocrystalline cells have been predominantly installed on residential rooftops to date, they are now being increasingly used for large-scale facilities. Analysts expect the market share for monocrystalline products to draw level with polycrystalline cells and modules worldwide. Three years ago, monocrystalline technology only had a share of approximately 30 percent. According to IHS Markit, the price of monocrystalline wafers sank to USD 0.133 per watt in the first half of 2018. This meant that they were only around 10 percent more expensive than polycrystalline wafers, but this was offset by a higher level of efficiency. This cost advantage was made possible in part by utilizing efficient diamond wire technology for sawing wafers, as well as the triumph of PERC solar cells, which contain both a passivated emitter and a passivated rear cell. According to data from the German Mechanical Engineering Industry Association (VDMA), monocrystalline cells in particular benefit from this technology. In this way, the efficiency rating for monocrystalline cells can be increased by 1.7 percent in contrast to standard technologies, and that of polycrystalline cells by approximately 1 percent.
Half-cut cell modules are also on the rise. They are capable of halving the internal power within a module, thereby reducing electrical losses by up to 75 percent. This means that output can be increased by up to 3 percent. Switching from 4- to 6-busbar technology also has its advantages. The reduced space between the busbars and additional conductive tracks enable an increased output of up to 0.5 percent. The use of round wires as opposed to flat ribbon wires promises a further output increase of up to 2 percent. This reduces cell shading and reflects light back on to the module.