Is silica sand usable for photovoltaic cells - solar cells - in scarce supply?

Answer 1

From http://www.eia.doe.gov/cneaf/solar.renewables/page/solarreport/solar.html While demand for solar continued to grow in 2006, the supply of high-grade silicon used to make PV cells continued to impact the solar industry. Two types of solar companies are expected to perform well in this market. First are the silicon-based solar manufacturing companies that have secured stable silicon supplies. Second are the companies that focused on thin-film solar technology (thin film solar modules use either a very thin coating of silicon or other alternative materials with no silicon). Not surprisingly, thin-film PV cell and module shipments experienced the greatest percentage gain between 2005 and 2006, nearly doubling. Still, conventional crystalline silicon cells and modules shipments continued to dominate all PV technologies with 233,518 peak kilowatts shipped in 2006. However, its market share continued to decline to 69 percent from 76 percent in 2005 and over 95 percent a decade ago (Table 2.21 and Figure 2.8). Within this category, single-crystal shipments rebounded to 85,627 peak kilowatts, or slightly more than 25 percent of total shipments in 2006, compared to 71,901 peak kilowatts in 2005. Cast and ribbon silicon shipments, the predominant PV technology, rose sharply to 147,892 peak kilowatts in 2005, or nearly 44 percent of total shipments, compared to 101,065 peak kilowatts in 2005 (Table 2.21). Today, thin-film PV modules that use materials such as amorphous silicon (a-Si); cadmium telluride (CdTe); or copper indium gallium selenide (CIGS) are attracting much attention and are growing at an impressive rate, in part due to the shortage of silicon and high manufacturing costs associated with crystalline silicon cells. With the help of lower manufacturing costs and its versatility, thin film technology has ignited the competition with conventional crystalline silicon technology over the past couple of years. However, thin film modules are typically much less efficient than crystalline silicon modules with 7 to 10 percent efficiency compared to silicon's average 15 percent efficiency.