Jan 8 2010
The basic substrate used for the building of electrical circuits and capturing of sunlight and converting it into electricity is provided by polysilicon, which is considered as the backbone of the photovoltaic business and the semiconductor industry. In comparison with the electronic grade silicon that is used to make semiconductors, the purity of silicon can be much lower for making solar wafers. “Polysilicon for Solar Wafers” a techno-economic report, has been released by SRI Consulting. This report talks about the manufacturing economics and the process design for three major commercial processes.
The worldwide demand for polysilicon was around 50 thousand metric tons each year as of the third quarter of the year 2009. This demand has been evenly divided for solar applications and semiconductors. Silicon based photovoltaic grade producers have recently discovered the method of producing photovoltaic cells directly from polysilicon. Inexpensive manufacturing technologies are used instead of the previous expensive step in which polysilicon was first converted into higher purity single crystal silicon.
Anthony Pavone, senior consultant and author AT SRI Consulting, remarked that awareness of the competitive manufacturing costs is vital as a result of the overcapacity reached by the business. The demand for polysilicon was flat as a result of the worldwide economic recession of 2008-2009. But there was an increase in capacity due to subsidy provided by the government. Pavone stated that producers of polysilicon who find it difficult to compete on cost will be forced out from business.
Manufacturing economics and process designs are compared in the “Polysilicon for Solar Wafers” report. This comparison is made for Siemens reactors, directional solidification furnaces and fluidized bed reactors. The capital and production costs of the three processes are compared and this comparison is presented with the help of a common engineering methodology; product pricing, consistent feedstock, and design basis for a generic 5,000 metric ton per year grass roots plant.