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Relevance. А simple and up-to-date methodology is needed to assess the potential of electricity that can be obtained from solar power plants installed in different regions. The difficulty in assessing the potential of solar energy lies in the presence of some factors that affect electricity generation and depend on random events. Such factors include, first of all, the sky clarity, the direction of photovoltaic panels strictly to the Sun, dustiness, and ambient temperature. The literature uses different approaches to assess the potential of solar energy. This paper presents a methodology for evaluating the generation of electricity by a solar panel having a continuous solar tracking system, taking into account the dustiness and temperature of photovoltaic panels. The technique has been tested on an existing physical model. Aim. To study the existing methods for assessing the potential of solar energy and to select the most suitable ones for the central part of Russia. Object. Solar power plants. Methods. Empirical and analytical methods. Using data obtained from an operating solar station, the adequacy of the proposed methodology was assessed. Results. The selected methods take into account the hourly sky clarity index, which made it possible, with sufficient accuracy for engineering techniques, to determine the daily power generation of a solar station with different angles of inclination of solar panels. This will improve the accuracy of estimating the potential of electricity generated by solar power plants, both with stationary photovoltaic panels and with solar tracking systems. Based on the conducted computational experiments and the analysis of data obtained from an operating solar station, the authors concluded that the technique presented in this paper allows us to determine with high enough accuracy the potential of electricity that can be produced in Russia by solar stations.

Abstract Dust and water vapor are important constituents in the Martian atmosphere, exerting significant influence on the heat balance of the atmosphere and surface. We have developed a method to retrieve optical and physical properties of Martian dust from spectral intensities of direct and scattered solar radiation to be measured using a multi-wavelength environmental camera onboard a Mars lander. Martian dust is assumed to be composed of silicate-like substrate and hematite-like inclusion, having spheroidal shape with a monomodal gamma size distribution. Error analysis based on simulated data reveals that appropriate combinations of three bands centered at 450, 550, and 675 nm wavelengths and 4 scattering angles of 3°, 10°, 50°, and 120° lead to good retrieval of four dust parameters, namely, aerosol optical depth, effective radius and variance of size distribution, and volume mixing ratio of hematite. Retrieval error increases when some of the observational parameters such as color ratio or aureole are omitted from the retrieval. Also, the capability of retrieving total column water vapor is examined through observations of direct and scattered solar radiation intensities at 925, 935, and 972 nm. The simulation and error analysis presented here will be useful for designing an environmental camera that can elucidate the dust and water vapor properties in a future Mars lander mission.

Automated Sun-tracking systems are important elements of solar power devices, which make it possible to increase the amount of solar energy converted to consumer formats during the daylight period, especially true for devices with solar energy concentration. In this study, we investigated the parameters of functioning of the Sun-tracking system built into the photovoltaic thermal installation with parabolic cylindrical concentrators of solar radiation, as well as the main characteristics of the complex as a whole. With attention to the installation structure and tracking system schematics, the studies were carried out on natural solar radiation, with simultaneous measurement of the photovoltaic characteristics and the solar radiation flux density using a pyranometer. The installation parameters were estimated in relation to the angular motion of the Sun across the celestial hemisphere. Due to numerous heterogeneous factors affecting the result, the experimental data were largely statistical in nature. For this reason, the parameters were evaluated using methods of regression analysis. In a number of experimental dependences, the correlation coefficient of the short-circuit current and the solar radiation flux density reached 98%. The studies allowed us to estimate the accuracy of Sun tracking at 1.5–2 angular degrees. In this case, the short-circuit current in the photovoltaic part of the installation varied by ±4% within an hour. In the course of field studies, the fraction of scattered solar radiation was estimated at ~20% of the total intensity. The concentration coefficient of 5.0–5.1 times was calculated from the dependence of the short-circuit current on the solar radiation intensity. [ABSTRACT FROM AUTHOR]

Dust and water vapor are important constituents in the Martian atmosphere, exerting significant influence on the heat balance of the atmosphere and surface. We have developed a method to retrieve optical and physical properties of Martian dust from spectral intensities of direct and scattered solar radiation to be measured using a multi-wavelength environmental camera onboard a Mars lander. Martian dust is assumed to be composed of silicate-like substrate and hematite-like inclusion, having spheroidal shape with a monomodal gamma size distribution. Error analysis based on simulated data reveals that appropriate combinations of three bands centered at 450, 550, and 675 nm wavelengths and 4 scattering angles of 3°, 10°, 50°, and 120° lead to good retrieval of four dust parameters, namely, aerosol optical depth, effective radius and variance of size distribution, and volume mixing ratio of hematite. Retrieval error increases when some of the observational parameters such as color ratio or aureole are omitted from the retrieval. Also, the capability of retrieving total column water vapor is examined through observations of direct and scattered solar radiation intensities at 925, 935, and 972 nm. The simulation and error analysis presented here will be useful for designing an environmental camera that can elucidate the dust and water vapor properties in a future Mars lander mission. [ABSTRACT FROM AUTHOR]

Abstract: The method of monitoring the vertical column density (VCD) of atmospheric pollution gases by using the scattered solar radiation is proposed and the scheme to ensure the necessary condition is put forward. Under the condition, the VCD of tropospheric NO2 is retrieved from the scattered solar radiation, which is close to that from the direct solar radiation. [Copyright &y& Elsevier]