Showing papers in "Solar Energy in 1978"

TL;DR: In this article, the attenuating properties of the atmosphere are presented in a form that permits the calculation of direct, diffuse and global spectral solar irradiance at ground level, using the extraterrestrial irradiance values of Thekaekara.

TL;DR: In this article, a number of new semiconductors with smaller band gaps, such as Fe2O3, WO3 and p-GaP, are studied for hydrogen production in sunlight.

TL;DR: In this paper, the procedure for calculating the position of the sun by computer is discussed, and the equations used to generate the values in The American Ephemeris and Nautical Almanac are presented in a simplified form that allows the sun to be calculated rapidly to an accuracy of 0.01°.

TL;DR: In this paper, the effects of storage capacity, storage unit heat transfer characteristics, collector area and location on the system performance are investigated for systems utilizing sodium sulfate decahydrate and paraffin wax as storage media.

TL;DR: In this paper, the authors used hourly wind data from the National Climatic Center (NCC) to study probability density functions of wind velocity and wind power and run duration persistence.

TL;DR: An easier method, using daily φ -charts, rather than the original hourly φ-curves, is presented, which greatly reduce the calculations required to determine flat-plate collector utilizability.

TL;DR: In this article, a numerical model based on standard meteorological data, as described above, can be used to extend the data base for design purposes, and the model is used to compute the amount of direct solar flux.

TL;DR: The most important results from the 100 MWe commercial model optimization study are: Staggers are better than cornfields and the increased cost of the tower and receiver subsystems has moved the solution to a larger cell size and a shorter tower.

TL;DR: In this article, a suitable method is proposed for predicting the mean monthly values of direct, diffuse, and total solar radiation at different locations in Iran, based on the assumption that the direct and diffuse components of solar radiation are primarily functions of solar zenith angle and cloud cover.

TL;DR: In this paper, the optical absorption properties of a high temperature molten salt heat transfer fluid were measured from 0.35 to 2.5 μm using both hemispherical transmission and reflection techniques.

TL;DR: In this article, a theoretical model is described that is designed to give the total global insolation falling on the earth's surface and the transmission of the atmosphere, compared to a model by Braslau and Dave.

TL;DR: In this article, the authors investigated two diffuser-augmented wind turbine design concepts and found that the specific power costs for a realistic DAWT configuration are lower than conventional wind turbines for very large size rotors, above 50 m diameter, and for rotor diameters less than about 20 m.

TL;DR: In this article, the authors examined the maximum solar energy available to an Earth-surface collector as a function of latitude, the north-south tilt of the collector from the Earth's surface (θ), and whether the collector is an ideal tracker (follows the Sun both north-South and east-West), an east-west tracker, or a fixed type.

TL;DR: In this paper, the theoretical maximum useful work obtainable from solar energy has been calculated taking account of its directional character, and the method employed is the calculation of the availability of a thermodynamic system containing such energy in an environment corresponding to the earth's surface.

TL;DR: In this article, the photochemical conversion of solar energy is reviewed in terms of utilization of photoactive organic materials and the economic and physical requirements of a photochemical storage material are outlined.

TL;DR: In this article, the authors have obtained a periodic solution of the one dimensional partial differential equation of heat conduction in the roof, which satisfies the periodic boundary conditions at the two surfaces of the roof.

TL;DR: In this paper, both Parabolic and Non-Parabolic Asymmetrical Concentrators are examined and compared with symmetrical designs, and the advantages of asymmetrical systems are: (1) a concentration vs time-of-day relationship which can be designed to compensate for projected solar area fall-off in early morning and late afternoon, allowing more uniform output where this is desirable; (2) greater operational flexibility for accommodating unexpected fluctuations in demand; (3) easier adaptation to vacuum-insulated receivers in one configuration; (4) substantially increased concentration and energy collection per unit of

TL;DR: The principles of solar water pumping are briefly described in this article, where the mechanical energy needed for pumping water may be produced by thermodynamic, or direct-conversion methods in thermodynamic conversion a fluid with high internal energy is produced in solar collectors or concentrators.

TL;DR: In this paper, a one-dimensional single-phase conductivity model of packed beds in which air and rock are at the same temperature is used to develop closed-form analytical solutions for the transient responses produced by time-varying air inlet temperatures.

TL;DR: In this article, an analysis is presented to predict the local rate of solar energy absorption in a pond using the radiative transfer theory, where the physical model considers absorption and scattering by the water and internal reflection of radiation from the air-water interface as well as the bottom.

TL;DR: In this paper, an approximate equation for predicting the solar transmittance of transparent honeycombs is presented, based on the optical properties of the honeycomb wall material, averaged over the solar spectrum.

TL;DR: In this paper, a feasibility study of open cycle air conditioning systems that use solid desiccants and solar energy has been performed, and two configurations evaluated are the ventilation mode, in which ambient air is continually introduced into the room, and the recirculation mode in which room air is recirculated.

TL;DR: A discussion of the use of plastic materials in solar energy applications is presented in this article, with particular emphasis on their suitability and durability, and the aging behavior of most of these plastics has been widely studied for normal outdoor exposure and in artificial weathering devices, and are thus briefly described here.