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Copyright of Revista de la Universidad del Valle de Guatemala is the property of Universidad del Valle de Guatemala and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ingeniería (0121-750X) is the property of Ingenieria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A direct expansion solar assisted heat pump (BCAES-ED) is a water heating technology with great potential in countries located in tropical and humid areas, so it is important to conduct energy and exergy-based analyzes that allow characterization its operation and promote its application in industrial processes. The present study used meteorological parameters that influence an experimental installation located in Portoviejo-Ecuador for a collector / evaporator of 3 and 1.5 m2 and compressor rotation speeds of 400 and 600 rpm. The energy analysis reported a coefficient of performance of the system between 3.5 and 4.5. The compressor obtained the highest value of exergy destruction, followed by the solar collector, the condenser and the expansion valve. The exergy efficiency of the system reached the value of 70%. The feasibility and advantages of using this technology in tropical countries are demonstrated. [ABSTRACT FROM AUTHOR]

Copyright of Revista Técnica Energía is the property of Centro Nacional de Control de Energia CENACE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista AUS is the property of Revista AUS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper shows the feasibility of implementing solar heating in Bariloche (3,600 degrees/day, 8.4°C mean annual temperature) through heat pipe collectors and water contained in insulated water tanks for further use through floor heating systems. Dynamic thermal models are used to optimize the system in order to meet 13,000 kWh annual demand, which represents both a 50m2 single-family, non-insulated affordable housing unit (260kWh/m2) or a 100m2 insulated unit (130 kWh/m2.) Such a demand could be met through five standard collectors, each containing 20 pipes (2,088m2, opening area), and a 63m3 tank at a cost of USD 27,000 or eight collectors and an 11m3 tank at a cost of USD 11,650. This paper discusses the reasons why Bariloche, whose mean temperature is similar to that of developed countries located in cold areas, achieves more economical solutions such as: a) the use of vacuum collectors instead of flat-plate collectors; b) properly distributed solar resources and heat demand; and c) an affordable type of water tank that enables proper insulation. This study concludes there is potential for the implementation of this technology in large parts of South America requiring heating solutions. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Arquitectura (1657-0308) is the property of Universidad Catolica de Columbia, Facultad de Arquitectura and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ciencia en su PC is the property of Instituto de Informacion Cientifica y Tecnologica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to utilize sustainable solar energy, cyclic operations of syngas production by methane reforming (reduction) and subsequent hydrogen production by water splitting (oxidation) were performed by using simulated solar-light irradiation to ZrO2-supported CeO2 particles which were coated on a SiC ceramic foam disk. This redox process is a promising chemical pathway for storage and transportation of solar heat by converting solar energy to chemical energy. By properly adjusting the methane reforming time, carbon deposition due to the undesirable methane decomposition could be avoided. The produced syngas had the H2/CO ratio of 2.0, which is suitable for the Fischer-Tropsch synthesis or methanol synthesis, and the produced pure hydrogen can be used for fuel cells. When the cyclic reactions were repeated several times at two temperatures (800 °C,900°C), the conversion of CeO2 and the H2 yield were reasonable and were maintained nearly constant from the second cycle, exhibiting good stability of the redox process. [ABSTRACT FROM AUTHOR]

selective film is modeled. The wavelength selective film is coupled with a compound parabolic concentrator (CPC) to reflect and concentrate the infrared portion of the solar spectrum onto a tubular absorber while transmitting the visible portion of the spectrum to an underlying thin-film photovoltaic module. The optical performance of the CPCI selective film is obtained through Monte Carlo ray tracing (MCRT). The CPC geometiy is optimized for maximum total energy generation for a roof-top application. Applied to a roof-top in Phoenix, AZ, the hybrid PVIT provides 20% more energy compared with a system of the same area with independent side-by-side solar thermal and PV modules, but the increase is achieved at the expense of a decrease in the electrical efficiency from 8.8% to 5.8%. [ABSTRACT FROM AUTHOR]

The design and manufacture of a two-axis sun tracking system (rotation-elevation), which controls a heliostat of a solar furnace for clay brick firing is presented. The system works with motors controlled through a personal computer. The algorithm for the sun tracking system was developed in a visual programming language, calculates the primary and secondary tracking angles of the heliostat and shows them in a screen. The microcontroller is programmed to control the step driver engines, which move the heliostat of the solar furnace. The primary and secondary tracking is the same for the equinoxes, whereas for the solstices are different because the solar altitude is greater in summer than in winter in the northern hemisphere. The sun tracking system permits a more efficient capture of the solar radiation since it continuously follows the apparent movement of the Sun. [ABSTRACT FROM AUTHOR]

the present work evaluates the behavior of the temperature of the flow of air in a solar collector of channel of rocks, by means of a mathematical model that simulates the temperatures from the flow of air to the entrance and exit of the collector. the pattern relates the geometry, the incident radiation in the collector and the constants own collector determined experimentally. For the analysis they were carried out three tests in those that the temperatures of the atmosphere were measured, of entrance and exit in the collector and the solar incident radiation. [ABSTRACT FROM AUTHOR]

Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction. The Gran Hotel SA organization, founded in 1965, used ACPM fuel boilers for eating water. The development of the hotel business generated a high consumption of energy and water in the rooms and the restaurant area. Therefore, control actions.were required. Methodology. We implemented a series of actions to control energy and water consumption. Results. With the change of boilers to solar panels for water heating, the level of CO2 sent to the atmosphere was reduced, also was noise pollution and the heat in the laundry area, fact that improved the quality of life of the people working in that area. We also adapted the pipe that distributes water, and it resulted in a decrease in the consumption of water. Additionally, with the change of illumination systems there were savings in energy consumption, and the updating of the washing and drying machines dropped the energy and water consumption. Conclusion. The implementation of C+P in the Gran Hotel SA organization improved conditions of occupational health in the staff and also improved environmental conditions. [ABSTRACT FROM AUTHOR]

Copper tubes were drilled with thermal flow drilling. Conventional HSS drills diameters were used to make pre drilling holes. Different height bushings were made. Two of the bushing heights were selected. The bushing circularity was measured. A ø 12,7 mm tube was welded perpendicularly on a ó 28,6 mm tube. A especial support device was designed and it was adapted to the Universal Test Machine, to determine the tensile stress of the brazing joint. The micro hardness and metallographic test were made in the brazing zone. As a conclusion the lower height bushing is enough to reach the maximum resistance. [ABSTRACT FROM AUTHOR]

It is described the technical and economic feasibility analysis of the solar drying of parchment coffee in floor of improved concrete. It is presented in a comparative way the study of the kinetic of the dried and the economic valuation of the effect of the blackened floor, the one which permits to reduce the time of dried with a smaller cost/benefit at the technological process. [ABSTRACT FROM AUTHOR]

Long-term performance estimations were performed on a nonstandard domestic solar water heating system by f-Chart, interactive F-CHART software, and ɸ, f-Chart methods. Results of estimations were compared to gain insight of their applicability. Results from F-CHART software and f-Chart agree well and are greater than those from the ɸ, f-Chart method. Energy dumping should be given thorough reconsideration for the refinement of f-Chart and F-CHART software. [ABSTRACT FROM AUTHOR]