In today’s solar power industry, about 90% of solar panels are made from silicon materials. The price of silicon photovoltaics has fallen significantly enabling it to be a key driver for the success of solar energy. However, a disadvantage of silicon photovoltaics is that the cells use 1,000 times more light absorbing material than alternative options. Another downside of silicon solar cells is their manufacturing requires expensive ultra-high-purity silicon. As a result, there is a lot of interest in alternative photovoltaic materials. A few promising new materials include dye-sensitized solar cells, organic photovoltaics, perovskite solar cells, and quantum dot photovoltaics.
A key feature in evaluating alternative solar photovoltaic materials is cell efficiency. Cell efficiency is defined as the portion of sunlight that can be converted to electricity via photovoltaics. Figure 1 compares the cell efficiency of alternative materials and silicon cells. Although most alternative materials have low efficiencies in comparison to silicon cells, perovskite cells come close to the efficiency of silicon photovoltaics.
Figure 1: Solar panel material efficiency (Source: C&EN)
Another metric in evaluating alternative solar photovoltaic materials is their commercial status. Figure 2 shows the commercial status and performance of alternative materials against silicon. Although alternatives such as dye-sensitized cells and organic photovoltaics have good performance and commercial status, silicon cells still outperform them. With further R&D over the next several years, one may expect that some of these alternative materials will demonstrate efficiency, performance, and commercial status similar to those for silicon photovoltaic cells.
Figure 2: Commercial and performance comparison of solar panel technologies (Source: C&EN)
-Sina Vahabzadeh and Uday Turaga
