Energy requirement for the production of silicon solar arrays. Third quarterly report, June 21, 1977--September 20, 1977. Solarex report No. SX/111/3

An assessment of potential changes and alternative technologies which could impact the photovoltaic manufacturing process is presented. The recent introduction of a new multiple wire saw into the market could impact the prevailing production sequence in the near future. A review of the potential of the saw indicates that upon its implementation into the wafering process, the overall payback time would be reduced to 4.2 years. The quest for a higher silicon utilization led to the development of ribbon growth techniques which allow the growth of silicon sheet directly from the melt. Although the future viability of a ribbon growth process is not denied, important changes and improvements need to be undertaken in order to reach its intended goal. In order to circumvent the energy demanding crystal growth process, Solarex is currently conducting experiments in silicon casting and efforts to estimate the energy expenditure. An expose of semicrystalline solar cells obtained from casted silicon is presented. Finally, the development of a computer model of a future large-scale solar power plant is reported.