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Estimates of the efficiency of solar installations in the Sun tracking mode presented in the literature are often ambiguous due to nonidentical comparison criteria and irradiation conditions. It is pro-posed to evaluate this characteristic systematically by two indicators - orientation and energy. The first is numerically equal to the current value of the cosine of the illumination angle of the receiving surface. And the second - the daily exposure of the tracking surface, attributed to the maximum value with ideal tracking of the Sun by a biaxial rotary device. Both indicators are calculated under the assumption of irradiation with three streams of solar energy in clear skies, which change during the day according to the model of the European Solar Radiation Atlas (ESRA). posed to evaluate this characteristic systematically by two indicators - orientation and energy. The first is numerically equal to the current value of the cosine of the illumination angle of the receiving surface. And the second - the daily exposure of the tracking surface, attributed to the maximum value with ideal tracking of the Sun by a biaxial rotary device. Both indicators are calculated under the assumption of irradiation with three streams of solar energy in clear skies, which change during the day according to the model of the European Solar Radiation Atlas (ESRA). The relationships between the fluxes of solar radiation at different atmospheric states are taken into account by the Linke turbidity factor. The unit of comparison of the efficiency of uniaxial tracking is the daily exposure of the surface the biax ial tracking device, the angle of illumination of which during the day is zero. Four variants of estimation of efficiency concerning direct and full streams of solar radiation at two variants of distribution of brightness of the sky - isotropic and non-isotropic in the Hay-Davies model approximation are considered. The simulation results are presented in tabular and graphical forms. [ABSTRACT FROM AUTHOR]

Improving the efficiency of converting solar radiation energy into electricity by solar cells is the main task of solar energy. And the modern interest in the design and operation of photovoltaic batteries based on solar cells leads to the evaluation of their main performance characteristics. To control the quality and efficiency of a solar cell in production or in the laboratory, it is necessary to accurately measure its volt-ampere characteristic, which is the main source of information about the parameters and characteristics of the solar cell, such as efficiency, maximum power, short circuit current, no-load voltage, current and voltage at maximum power, form factor, etc. When designing photovoltaic batteries of large areas, ground or space applications, there are difficulties in determining the various losses, such as switching of photocells, their non-identity, uneven temperature and illumination of photovoltaic batteries. Usually these losses are taken into account by introducing various coefficients into the mathematical model. Experimental studies in the direction of more accurate determination of all kinds of losses in photovoltaic batteries lead to non-payback and complicate the conduct of such experimental studies. For the design and testing of large-area photovoltaic batteries, the authors propose an approach that is based on the construction of volt-ampere characteristics of photovoltaic batteries. The proposed approach allows to determine the free-ampere characteristics of an individual solar cell or groups of photovoltaic converters, to obtain models at different levels of illumination and temperature with the characteristic parameters of photovoltaic batteries of any area. The authors conducted an experimental confirmation of the proposed method, as well as a comparison with other experimental studies. The method identifies the transition coefficients of the mathematical model, as well as the features of the proposed approach. Bibl. 6, Fig. 2. [ABSTRACT FROM AUTHOR]