Excellent power-generating properties by using the HIT structure

We are developing HIT solar cells with high conversion efficiency, which was achieved the world´s highest conversion efficiency of 22.3% in a practical size solar cell in July 2007. We have four main approaches to reducing power-generating cost: improve the conversion efficiency, apply the HIT structure to a thin wafer, improve the temperature coefficient, and apply HIT solar cells to a bifacial solar module. Using these approaches, we have achieved the remarkably high conversion efficiency of 21.4% due to a high Voc of 0.739 V with an 85-μm cell, which was measured at SANYO. A thinner Si wafer brings not only high Voc but also generating more output power at high temperature for a better temperature coefficient. We have confirmed that the HIT structure is suitable for use in thinner wafers, allowing us to reduce power-generating cost.