The Luminescent Solar Concentrator (LSC) consists of a transparent polymer plate, containing luminescent particles. Solar cells are connected to one or more edges of the polymer plate. Incident light is absorbed by the luminescent particles and re-emitted. Part of the light emitted by the luminescent particles is guided towards the solar cells by total internal reflection. Since the edge area is smaller than the receiving one, this allows for concentration of sunlight without the need for solar tracking. External Quantum Efficiency (EQE) and current-voltage (I-V) measurements were performed on LSC devices with multicrystalline silicon (mc-Si) or GaAs cells attached to the sides. The best result was obtained for an LSC with four GaAs cell power conversion efficiency of this device, as measured at European Solar Test Installation laboratories, was 7.1% (geometrical concentration of a factor 2.5). With one GaAs cell attached to one edge only, the power efficiency was still as high as 4.6% (geometrical concentration of a factor 10). To our knowledge these efficiencies are among. the highest reported for the LSC

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The performance of a photovoltaic module at Standard Test Conditions (STC) is valuable for comparing the peak performance of different module types. It does not, however, give enough information to accurately predict how much energy a module will deliver when subjected to real operating conditions. There are several proposals for an energy rating for PV modules which attempt to account for the varying operating conditions that one encounters in the field. In this paper, we present an approach with the emphasis on simplicity and practicality that incorporates existing standard measurements to determine the energy output as a function of global in-plane irradiance and ambient temperature. The method is applied to crystalline Si modules and tested with outdoor measurements, and a good accuracy of prediction of energy production is observed. Finally, a proposal is made for a simple Energy Rating labeling of PV modules.

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This paper describes the measurement of photovoltaic module performance over a range of temperatures and irradiances according to the international standard IEC 61853 Part 1. The purpose of this work is to assess the reproducibility of power matrix measurements obtained using two methods specified in the standard: under natural sunlight with a tracker, and with a solar simulator. A comparison of results using the third principal method (under natural sunlight without tracker) is also summarised for completeness. The same measurement techniques have been employed to measure four modules of different technologies, namely mono and poly crystalline Si, CdTe and CIS. The method used to vary the irradiance in the natural sunlight with tracker and solar simulator approaches is based on un-calibrated mesh filters. The uniformity and effect on spectrum of the mesh filters have been studied, and the impact of these on the measurements estimated. Measurements from all methods are compared over as much of the ranges as possible. The results show that for all modules, the reproducibility is within the estimated measurement uncertainty. The suitability of the different methods is discussed in light of the results and the limitations of the various methods as applied to different modules technologies. On the basis of the results, parts of IEC 61853 Part 1 will be introduced into the ISO 17025 laboratory accreditation at the European Solar Test Installation (ESTI).

We describe a genetic algorithm approach to solve an inverse problem in optics, which determines the characteristics of a fiber Bragg grating from its reflected spectrum. The validity of the proposed method is demonstrated by use of a Bragg sensor for the measurement of nonlinear strain acting on a uniaxial aluminum test specimen.