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For some industrial applications, an accurate estimation of a light source position is needed. That is the case for a heliostat, a device that projects sunlight onto a focus hundreds of meters away from its aiming point. In this paper, we present a novel sensor design for generating an alignment error signal. Included is a detailed study of its response, which shows that certain geometrical design parameters are necessary to achieve desired accuracy. This sensor has been implemented using microelectromechanical system techniques to achieve a robust structure at low cost and it has been successfully applied to sun-tracking systems. Experimental results obtained in field tests are included. Index Terms--Microelectromechanical system (MEMS), microsensors, power generation, solar energy, sun-tracking control.

Measuring open-circuit voltage (Voc) versus light intensity (Suns) in solar cells permits the access of cell performance without the series resistance effect. This article shows the implementation of a Suns–Voc measurement system that consists of an off-the-shelf photograph flash lamp, a digital oscilloscope, and a specifically designed photodetector board with three silicon photodiodes that covers a light intensity measurement range from 10−5 to 102 suns. The whole system is controlled via universal serial bus (USB) ports from a personal computer allowing the measurement of cell characteristics (pseudo-dark and pseudo-light current density–voltage curves, as well as the pseudo fill factor and pseudo efficiency) automatically in a very short time. [ABSTRACT FROM AUTHOR]

In this work, we report on the fabrication and characterization of n-type c-Si solar cells whose p+ emitters are based on laser processed aluminum oxide/silicon carbide (Al2O3/SiCx) films. The p+ emitter is defined at the rear side of the cell and it consists of point-like laser-diffused p+ regions with a surface charge induced emitter in between based on the high negative charge located at the Al2O3/c-Si interface. These emitters are fabricated at low temperature (< 400 °C) and could be directly compared to silicon heterojunction emitters with the advantage that the deposition of a Transparent Conductive Oxide (TCO) film can be avoided, since they are based on p+/n c-Si homojunctions. Additionally, the involved films are transparent to the IR photons (◻ >1000 nm) that reach the rear surface of the cell resulting in an excellent back reflector. We fabricated solar cells with distance between p+ regions or pitch ranging from 200 to 350 μm with a front surface based on silicon heterojunction technology. Best efficiency (18.1 %) is obtained for a pitch of 250 μm as a consequence of the trade-off between Voc and FF values. [ABSTRACT FROM AUTHOR]

Presents information on a study which described a novel concept of photovoltaic mini array assembly based on a flip-chip Multichip Module technology. Insight on substrate wafer fabrication; Methodology of the study; Results and discussion on the study; Conclusions.