The price allocation guidelines (PAG) are an integrated set of specific cost targets for several task areas within the Low-cost Solar Array (LSA) Project. PAG is a working tool of LSA Project management designed to provide consistent and meaningful guidelines for costs of polycrystalline silicon material, sheet, cells, encapsulants, and module manufacturing. It is expected that advanced photovoltaic concepts derived from industry and the research community can be developed so that it will be possible by the end of 1982 to demonstrate production processes, all process steps, and prototype equipment required to manufacture flat-plate photovoltaic modules. This demonstration would incorporate production rates and product quality consistent with a specific market price determined by the program. This stage of development has been referred to as Technical Readiness. A goal of $0.70 per peak watt (1980 dollars) has been established for the cost of electricity generated by photovoltaic modules. The processes for producing modules demonstrated to be technically ready must be amenable to scale-up so that this price goal can eventually be achieved in the marketplace. The guidelines described in this document allocate portions of that goal to each module component. Sheet materials derived from the following five technologies are considered: Czochralski, …

Efforts at the Jet Propulsion Laboratory toward the production of pure polycrystaline silicon are centered on the concept of silicon particle growth in a fluidized bed reactor (FBR) and a continuous flow pyrolyzer (CFP). The CFP possibly can provide the seed particles which will be grown to larger sizes in the FBR. In both the reactors polycrystalline silicon is obtaned from the pyrolysis of silane. A part of the JPL effort is to develop a model of silicon particle growth for the purpose of predicting particle growth rates and product particle size distributions in the FBR and the CFP. This repot describes the mathematical models of silicon particle growth in the FBR and the CFP.

This report describes progress made by the Low-Cost Solar Array Project during the period April through August 1979. It includes reports on project analysis and integration; technology development in silicon material, large-area sheet silicon, and encapsulation; production process and equipment development; engineering and operations, and a discussion of the steps taken to integrate these efforts. It includes a report on, and copies of viewgraphs presented at the Project Integration Meeting held August 22-23, 1979.

An analytical method has been developed for determining the minimum thickness for simply supported, rectangular glass plates subjected to uniform normal pressure environmental loads such as wind, earthquake, snow, and deadweight. The method consists of comparing an analytical prediction of the stress in the glass panel to a glass breakage stress determined from fracture mechanics considerations. Based on extensive analysis using the nonlinear finite element structural analysis program ARGUS, design curves for the structural analysis of simply supported rectangular plates have been developed. These curves yield the center deflection, center stress and corner stress as a function of a dimensionless parameter describing the load intensity. Results are included for plates having length-to-width ratios of 1, 1.5, 2, 3, and 4. The load range considered extends to 1000 times the load at which the behavior of the plate becomes significantly nonlinear. Over the load range analyzed, the analysis shows that the ratio of center deflection to plate thickness for a plate of length-to-width ratio of 4 is less than 70 to 1, whereas linear theory would predict a center deflection about 1200 times the plate thickness. The stress is also markedly lower than would be predicted by linear theory. These analytical …

Silane pyrolysis in a continuous flow pyrolyzer is a simple process that is currently being developed for producing solar cell grade silicon. The process involves complex phenomena, however, including thermal decomposition of silane, nucleation and growth of silicon particles, and mass and heat transfer. Modeling the effects of transport phenomena on silane pyrolysis in a continuous flow pyrolyzer is discussed. One- and two-dimensional models are developed to predict velocity, temperature, and concentration profiles in the reactor. The one-dimensional model has been implemented as a computer code.

A computer-assisted thermochemical equilibrium analysis was conducted for the silicon transport reaction: Si(s) + SiF/sub 4/(g) = (intermediates) = Si(s) + SiF/sub 4/(g). The calculations indicated that a substantial transport rate should be possible at temperatures of 1700/sup 0/K and one atmosphere pressure. Computations were made to determine whether the elemental impurities present in metallurgical-grade silicon would transfer in this process. It was concluded that aluminum, chromium, copper, iron, manganese, molybdenum, nickel, vanadium, and zirconium would not transfer, but that boron, magnesium, phosphorus, and titanium would transfer.

An environmental test chamber providing acceleration of uv radiation and precise temperature control (+- 1/sup 0/C) has been designed, constructed and tested. This chamber allows acceleration of solar ultraviolet up to 30 suns while maintaining temperature of the absorbing surface at 30/sup 0/C to 60/sup 0/C). This test chamber utilizes a filtered medium pressure mercury arc as the source of radiation, and a combination of selenium radiometer and silicon radiometer to monitor solar ultraviolet (295 to 340 nm) and total radiant power output, respectively. Details of design and construction and operational procedures are presented along with typical test data. The test chamber was designed for accelerated testing of solar cell modules.

The Solar Array Manufacturing Industry Costing Standards (SAMICS) provide standard formats, data, assumptions, and procedures for determining the price a hypothetical solar array manufacturer would have to be able to obtain in the market to realize a specified after-tax rate of return on equity for a specified level of production. This document presents the methodology and its theoretical background. It is contended that the model is sufficiently general to be used in any production-line manufacturing environment. Implementation of this methodology by the Solar Array Manufacturing Industry Simulation computer program (SAMIS III, Release 1) is discussed.

The Solar Array Manufacturing Industry Costing Standards (SAMICS) provide standard formats, data, assumptions, and procedures for determining the price a hypothetical solar array manufacturer would have to be able to obtain in the market to realize a specified after-tax rate of return on equity for a specified level of production. This document summarizes the methodology and its theoretical background. It is contended that the model is sufficiently general to be used in any production-line manufacturing environment.

This specification establishes minimum design, qualification and acceptance requirements for terrestrial solar cell modules suitable for incorporation in photovoltaic array applications in the 20kW to 500kW range, such as defined by Department of Energy PRDA EM-D-04-0038. Both mandatory and recommended requirement levels for selected performance criteria have been specified for modules within these arrays. As applicable, the manufacturer/contractor shall be responsible for generation and selection of appropriate design or test levels within the scope of these criteria. Specification of any additional requirements as necessary to satisfy the particular array or system application shall be the responsibility of the manufacturer/contractor. Environmental requirements imposed by this specification are considered to be the minimum level acceptable to DOE. Test procedures are detailed.

The retention of particulate contamination on the surface of flat-plate photovoltaic devices is adversely affecting electrical performance of outdoor-exposed modules. The results of an experimental study being performed by the Jet Propulsion Laboratory's Low-Cost Solar Array Project to characterize and understand the effects of outdoor contaminants on sensitive optical surfaces of flat-plate photovoltaic modules and cover materials are described. Comparative electrical and optical performance data from photovoltaic modules and materials subjected to outdoor exposure at field test sites throughout the United States have been collected and examined. The results show significant time- and site-dependence. During periods when natural removal processes do not dominate, the rate of particulate contamination accumulation appears to be largely material-independent. The effectiveness of natural removal processes, especially rain, is strongly material-dependent. Glass and acrylic top-cover materials retain fewer particles than silicone rubber does. Side-by-side outdoor exposure testing for long duration is presently the most effective means of evaluating soiling differences between materials. Changes in spectral transmission as a function of time and location and limited scattering data are presented.

This specification establishes minimum design, qualification and acceptance requirements for terrestrial solar cell modules suitable for incorporation in photovoltaic array applications in the 20 kW to 500 kW range, such as defined by Department of Energy PRDA EM-D-04-0038. Both mandatory and recommended requirement levels for selected performance criteria have been specified for modules within these arrays. As applicable, the manufacturer/contractor shall be responsible for generation and selection of appropriate design or test levels within the scope of these criteria. Specification of any additional requirements as necessary to satisfy the particular array or system application shall be the responsibility of the manufacturer/contractor. Environmental requirements imposed by this specification are considered to be the minimum level acceptable to DOE.

Progress made by the Low-Cost Solar Array Project during the period April to September 1980, is reported in detail. Progress on project analysis and integration; technology development in silicon material, large-area silicon sheet and encapsulation; production process and equipment development; engineering, and operations is described. A report on, and copies of visual presentations made at, the Project Integration Meeting held September 24 and 25, 1980 are included.

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