Shondip Ghosh

A CPV Thesis

The viability of a concentrator technology is determined by five interrelated factors: economic benefit, cell performance under concentration, thermal management, optical performance and manufacturability. Considering these factors, the 5- 10x concentration range is ideal for silicon-based receivers because this level of concentration captures the bulk of available economic gains while mitigating technical risk. Significant gains in capital efficiency are forsaken below the 5x concentration level. Above the 10x level of concentration, marginal improvements to economic benefit are achieved, but threats to reliability emerge and tend to erode the available economic benefit. Furthermore, optic solutions that provide for concentration above 10x tend to force a departure from low-profile flat-plate designs that are most adoptable. For silicon based receivers, a 5-10x level of concentration within a traditional module form factor is optimal.

Latest ATIR Module Performance And A Vision Of Things To Come

While the motivation for concentrating photovoltaics (CPV) is simple, namely the ability to scale production while minimizing capital expenditure and at the same time decrease per unit costs by replacing semiconductor with commodity materials, large scale adoption of CPV lags. This resistance to adoption is due in part to high system costs, insufficient optical efficiency, unproven reliability, and a general misfit of CPV designs with existing system‐level infrastructure. The use of aggregated total internal reflection (ATIR) as the optical mechanism around which one constructs a CPV module provides a unique opportunity to overcome these challenges. We present here the module‐level results of a first series of prototypes that not only achieves competitive optical efficiencies, but does so in a more traditional flat form factor, with acceptance angles that allow conversion of a large percentage of the diffuse resource (±2.9° daily, ±28.0° seasonal, at 95% of peak power), and uniform light flux on the cell ...

Aggregated Total Internal Reflection Optics for Solar

An agglomeration of factors has stifled the economic promise of CPV. Foremost among these factors are: insufficient optical efficiency, misfit with existing solar infrastructure, high costs, and inadequate reliability of the optic‐receiver package. These difficulties are significantly driven by the choice of optic. The CPV industry is constrained in a paradigm of bulky reflective or refractive optics that operate best at either low concentration (2–5x) or high concentration (100x and above). Low concentration approaches are plagued by marginal economics, while high concentration approaches face technical risks and do not fit well with the existing solar infrastructure. Using total internal reflection as the primary optical mechanism, a cost effective, line‐focus optic can be produced at scale to provide superior optical performance in a flat profile and operate at a mid level of concentration to optimize the tradeoff between economic benefit and adoptability.