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This paper describes an approach of making the FLATCON® CPV technology compatible with standard photovoltaic simulation software like PVSYST and INSEL in order to facilitate yield estimations for potential power plant sites. Due to the use of triple-junction cells, the FLATCON® CPV module efficiency is more sensitive to changes in the solar spectrum than the efficiency of an average single-junction flat plate module. Besides that, the concentrating optics show a temperature dependency. These effects result in a non-linear component in the short circuit dependency on the direct normal irradiance. By means of introducing a "Utilization Factor", deduced from both measured data and theoretical considerations, these CPV peculiarities can be considered in standard software tools and transferred to other locations without the need of overly complex measurements or algorithms.

A six-parameter formula is proposed for describing the hourly alternating current performance of a grid-connected, passively cooled concentrator photovoltaic (CPV) system. These system parameters all have physical meanings, and techniques are described for deriving their numerical values. The predictions of the model are compared with the measured output of a Soitec CPV system at Sede Boqer and found to be accurate to approximately ± 5% at all times of the year. The model should also be valid for systems of similar construction operated in different climates from the system studied here, and also for passively cooled CPV systems of different designs provided that suitable numerical values are determined for their system parameters. Another possible use of the model is as a guide for tailoring CPV cell architecture to the particular spectral conditions of the locations in which they will operate. Attention is drawn to the fact that the numerical values of some of the system parameters are found to depend upon the time binning employed for the data. An explanation is given for this phenomenon, which is also found to occur for non-concentrating photovoltaic panels.

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This paper presents the new module generation (CX-75-III), which was developed in an all-embracing cost optimization. The single primary lens was refined for optical efficiency and its size increased to 5.7 x 5.7 cm², thus dramatically reducing the part count. Thermal simulations were used in order to dimension the heat spreader and ensure the reliability due to a low cell temperature. Furthermore, recent developments for cost optimization and high module efficiencies are presented. Results on prototype modules with a new heat spreader design, a new primary lens and also with refractive secondary optical elements are shown. The use of reflective secondaries has lead to an STC efficiency of 30.6%. Furthermore, different anti-reflection coatings have been examined in order to assess their impact on performance and reliability..