In this manuscript, distinct approaches were used in order to obtain the best electrical power estimation from photovoltaic systems located at different selected places in Mexico. Multiple Linear Regression (MLR) and Gradient Descent Optimization (GDO) were applied as statistical methods and they were compared against an Adaptive Neuro-Fuzzy Inference System (ANFIS) as an intelligent technique. The data gathered involved solar radiation, outside temperature, wind speed, daylight hour and photovoltaic power; collected from on-site real-time measurements at Mexico City and Hermosillo City, Sonora State. According to our results, all three methods achieved satisfactory performances, since low values were obtained for the convergence error. The GDO improved the MLR results, minimizing the overall error percentage value from 7.2% to 6.9% for Sonora and from 2.0% to 1.9% for Mexico City; nonetheless, ANFIS overcomes both statistical methods, achieving a 5.8% error percentage value for Sonora and 1.6% for Mexico City. The results demonstrated an improvement by applying intelligent systems against statistical techniques achieving a lesser mean average error.

Since August 2011, the 30 kWt Solar Furnace for Higher Radiative Fluxes (HoSIER) of the Renewable Energy Institute (former Center for Energy Research) of the National University of Mexico (IER-UNAM) is in operation. The optical design of the HoSIER-UNAM includes a total of 409 spherical facets, divided into 5 different focal length groups [1]. A ray-tracing simulation was carried out to realize a three-dimensional analysis of the concentrated solar radiation distribution at the focal area of the HoSIER. In this way, theoretical profiles of the radiative flux were obtained. To get the experimental profiles of the concentrated solar irradiance of the HoSIER, a Lambertian screen was placed in the focal zone, normal to the optical axis of the concentrator. The screen was moved along 10cm on the focus with each flat separated 5mm of distance and in front of a CCD 8-bit digital camera. With the CCD was possible to obtain several experimental radiative flux distributions and thus it was possible to validate the ray-tracing simulation. This comparison shows a very good agreement between experimental and theoretical distribution

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.