The radiation flux distributions produced by the concentrating solar systems used to produce thermal/electrical power are usually non-homogeneous. This results in non-uniform temperature distributions on the solar receivers, causing adverse effects on the system’s overall performance. An approach to better understand the problem is to study the surfaces around the focal zone where the radiation density is homogeneous (isosurfaces), generating them from experimental data. For this, it is necessary to superimpose built volumes of the different irradiance levels using parallel planes in different directions from the focal point of a concentrator. These volumes are known as effective volumes. This study presents the model used to generate effective volume produced by a point focus concentrator, comparing it with experimental results in a direction perpendicular to the focal axis. The effective volumes were developed considering a global optical error of the system of 2.8 mrad. The set of methods used to generate effective volumes has not been previously presented in the literature. The theoretical-experimental research consisted of the combination of the camera-target method and the simulations by the ray-tracing technique. The results showed effective volumes with the highest value of 10 MW/m2 and the lowest value of 4.5 MW/m2.

The need to achieve a uniform distribution of concentrated solar flux in the photovoltaic, thermal or any other receivers is a common problem; therefore, the optical characterization of the concentration system is necessary to determinate the physical characteristics of the receptors. In this work, a parabolic dish concentrator of 1.65x1.65 m2, developed by research from the University of Arizona, is optically characterized under normal operating conditions, also known as environmental conditions that refer to non-controlled conditions as solar radiation, environmental temperature and wind velocity that could affect slightly, by thermal and mechanical efforts, the distribution profiles of the concentrated solar radiation. The set used for the evaluation consisted of the parabolic mirror and Chilled Lambertian Flat Surface installed in the focal point on the optical axis of the mirror. The evaluation was divided into two parts: a theoretical part that consist on using ray tracing simulation and an experimental part that corresponds to image analysis. The used methodology in this work has been stablish in many researches, so this is a reliable method. The global optical error was 2.3 mrad under normal operating conditions.

Este artículo presenta el estudio experimental que consiste en el análisis del desempeño térmico y eléctrico de un sistema HCPV que cuenta con dos discos parabólicos y sus respectivas unidades de conversión de potencia (PCUs) configurados en una óptica especial conocida como XRX-Köhler. Este sistema utiliza celdas multi-unión, que, a pesar de su alta eficiencia, no utilizan entre el 60-70% de la radiación recibida por lo que esta energía debe ser retirada con un sistema de enfriamiento para mantener su temperatura dentro de un intervalo que asegure su integridad y el mejor desempeño de la misma. A diferencia de las celdas de unión sencillas, las MJ pueden operar a más altas temperaturas con eficiencias aceptables de producción eléctrica. Esta característica de operar en un rango amplio de temperaturas (~ 90°C), puede hacer que sistemas térmicos de aplicaciones solares funcionen con el calor residual y así mejorar el desempeño total del sistema. Se ha desarrollado una serie de campañas de pruebas experimentales para la evaluación tanto de las curvas I-V en forma instantánea como las eficiencias instantáneas eléctrica y térmica obteniendo valores de ~24% y de ~53%, respectivamente.

En el mundo, la incorporación de la energía limpia en el mix de la generación  de energía eléctrica se contempla con diferentes tecnologías como la eólica, geotermia, solar entre otras. En particular, la energía solar genera dos principales vectores energéticos, la electricidad obtenida a través de sistemas fotovoltaicos y combustibles solares, que, en algunos casos, son utilizados para la generación de energía eléctrica, con eficiencias y costos diferentes a los sistemas fotovoltaicos. Uno de los factores más importantes a considerar son los costos de la tecnología y su eficiencia.