Assessing the Potential of ‘Through Light’-Optimized APV Systems (TLO-APVs)’ for Agro-Voltaic Applications in Hyper-Arid Climates

Abstract

The concept of integrating sun-tracking mechanism in the CPV module itself, increased the potential for realizing high power densities in high-value applications where the CPV modules are installed at fixed orientation similarly to conventional PV. The most fully developed tracking integrated CPV systems with diffuse light transmission at this time appear to be the commercially oriented modules of the Swiss start-up Insolight. This technology uses biconvex lenses with high transmissibility to concentrate the direct light by 180 times onto high efficiency multijunction micro-size cells, while allowing the diffused irradiation to be transmitted for thermal storage or for illumination of buildings and in the context of our study: agriculture, leading to the co-location of electric power generation and farming. This research fully characterized the module optically, thermally, and electrically under the harsh, semi-arid climate of Abu Dhabi, United Arab Emirates which included the design and construction of a test-rig The peak electrical efficiency recorded is 26.13% coupled with a transmittance ratio of 26% that predominantly depends on the diffuse irradiance across the day rather than variations in the incidence angle. In situations prioritizing light transmittance over electrical output, utilizing the maximum light transmission mode, transmittance efficiency reaches a maximum of 71.61% which corresponds to a daily maximum of 1.8379×109 lumens/m2 and 29.69 PAR/m2 making it suitable for moderate daylighting applications and crops requiring high light intensity. On the thermal front, the temperature within the test-rig compartment surpasses the ambient temperature by a range of 10-15°C, with the disparity between the ambient environment and the solar cells being 27.3°C. A semi-empirical model was developed and tested to evaluate the performance of the technology and for economic analysis. The technology will be explained with focus on the optical behavior of the optics and how it changed with time under harsh thermal and irradiance conditions, and how the manufacturing process played a role in this behavior. Future testing the technology within an agro-voltaic field will be briefly outlined along with analysis on crop yield and evapotraspiration based on the characterization and model results. Metagenomics is introduced as a test to infer crops’ health status, potential for disease resistance, growth characteristics, and response to environmental factors.

Date of Award	20 Dec 2023
Original language	American English
Supervisor	Matteo Chiesa (Supervisor)