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Sample records for aire acondicionado solar

  1. El ruido en instalaciones de aire acondicionado

    Directory of Open Access Journals (Sweden)

    Alamán, Aurelio

    1964-04-01

    Full Text Available This article gives a general account of the noise problem in air conditioning systems. This problem causes grave concern to the technicians owing to its influence on the comfort of the buildings concerned. The acceptable levels of noise are discussed, also their codification into general specifications. Methods are given to test whether a given installation satisfies such noise specifications, and the means that are usually adopted to prevent air conditioning noise from extending into inhabited rooms. The study of the limitation of noise to a comfortable level depends both on the noise specifications and the actual design of the installation. Scale «A» is utilised in connection with the specifications, and the sound spectral curves are part of the design technique, which enables to obtain the cheapest design for the same level of comfort. The designer needs the fullest cooperation of the manufacturers, who should supply him with detailed accoustical data about the equipment. This applies both to installations that will produce noise and to the material that is meant to absorb it.Se expone en este artículo una idea general del problema del ruido en instalaciones de aire acondicionado, problema que preocupa hondamente en los medios técnicos correspondientes, por su gran influencia en el confort de los edificios. Se dan las cifras de niveles de presión sonora admisibles, recomendables para un Pliego de Condiciones, y el procedimiento para comprobar si las instalaciones terminadas lo cumplen, así como los medios normalmente utilizados para evitar la emisión de ruido a los locales habitados. Para el estudio del confort sonoro se recomienda tener en cuenta, tanto en el Pliego de Condiciones (mediante el empleo de la escala «A» como en el estudio de la eliminación de ruidos, al proyectar la instalación (mediante las curvas espectrales que se indican, no solamente el nivel sonoro global, sino, de acuerdo con la tendencia mundial, el espectro

  2. Aire Acondicionado Solar, para Conjunto de Viviendas en Mexicali, México Solar Air Conditioning for a Housing Compound in Mexicali, Mexico

    Directory of Open Access Journals (Sweden)

    Aníbal Luna

    2008-01-01

    Full Text Available El objetivo del presente trabajo es dimensionar y evaluar un sistema de enfriamiento por absorción LiBr-H2O asistido con energía solar y gas natural, para climatizar un conjunto de viviendas en Mexicali, Baja California, México. El análisis de comportamiento horario, diario y mensual en el periodo con mayor demanda de enfriamiento se realiza con el programa TRNSYS 16 y se busca la menor área de captación y la mayor fracción solar. Esto se traduce en el mínimo costo de operación e inversión inicial. Se encontró que el sistema genera condiciones del espacio entre confortablemente caliente y confortablemente frío, según la norma ISO 7730 (2005. Esto se logra a partir de 287 m²detubos evacuados, que aportan el 90% de la energía requerida. El sistema es técnicamente factible, ya que cubre la demanda de enfriamiento durante el periodo de verano y requiere un área de colección similar a la disponible en el conjunto de viviendas.The objective of the present work is to dimension and evaluate an absorption LiBr-H2O cooling system assisted by solar energy and natural gas for air conditioning of a group of housings in Mexicali, Baja California, Mexico. The analysis of the hourly, daily and monthly operating performance in the period with more cooling demand is carried out by mean of TRNSYS 16, and it is seeking the least collection area and the highest solar fraction; that which is translated in the minimum operation cost and initial investment. It was found that the system generates conditions of the space between comfortably warm and comfortably cold, according to ISO 7730 (2005, with 287 m² of evacuated tubes which contribute 90% of the required energy. The system is technically feasible, since it covers the cooling demand during the summer period and it requires a similar collecting area to the available one in the housing compounds.

  3. Voltage controller design for air conditioning; Diseno de controlador de voltaje para aire acondicionado

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Andrade, R; Lopez Villalobos, J.J; Valderrama Chairez, J; Ramirez, R.L. [Instituto Tecnologico de Nuevo Leon, Guadalupe, Nuevo Leon (Mexico)]. E-mails: roxana_garciaandrade@yahoo.com; xe2n@yahoo.com.mx; jose.valderrama@ieee.org

    2013-03-15

    This paper discusses the design of a voltage controller for an air conditioning system in order to generate additional power in activation or startup of the system, for which as a first stage is presented the modeling power generation of electric current through alternative means, such as solar energy. The results of this study will be the basis for development of the physical prototype of this system controller. [Spanish] El presente trabajo trata sobre el diseno de un controlador de voltaje para un sistema de aire acondicionado con el fin de generar energia adicional en la activacion o arranque de dicho sistema, para lo cual como primer fase se presenta el modelado de la generacion de corriente electrica mediante medios alternos, como lo es la energia solar. Los resultados de este trabajo seran la base para desarrollo del prototipo fisico de este sistema controlador.

  4. Potencial del techo verde, para ahorrar electricidad por aire acondicionado en la edificación

    Directory of Open Access Journals (Sweden)

    Ruber Trujillo Samayoa

    2015-01-01

    Full Text Available Introducción: Tanto en México como en el mundo, más de tres cuartas partes de los insumos que se usan en la producción de electricidad provienen de fuentes no renovables, en una realidad donde los techos de las edificaciones son responsables de un consumo importante de electricidad por aire acondicionado. Por lo anterior, el objetivo fue evaluar el aspecto térmico y la eficiencia en el consumo de electricidad de dos aires acondicionados colocados, bajo el Techo de concreto reforzado y el Techo verde, y a la vez utilizar a la geometría analítica como herramienta de análisis en el consumo de electricidad. Método: Aunque inicialmente la metodología de la climatología dinámica, fue desarrollada para el análisis térmico, en este trabajo se retomó para aplicarlo al consumo eléctrico y conjuntándolo con el apoyo de la geometría analítica, a través de ecuaciones de recta que representan promedios anuales, se evidenció las diferencias en el consumo. Resultados: Los resultados obtenidos demuestran que el Techo verde amortigua mejor las temperaturas exteriores, reduce la oscilación térmica y; en el consumo eléctrico, con una diferencia promedio anual de un 28%, el Techo Verde consumió menos energía eléctrica por aire acondicionado. Discusión o conclusión: Se demuestra que conviene el uso de techos verdes en el sitio de estudio y posibilita su aplicación en otros contextos. El trabajo se realizó en periodos de temperaturas extremas opuestas, invierno de 2014 y primavera de 2015.

  5. Estimated saving potential and efficient use of energy in air conditioning by means of the solar protection; Potencial estimado de ahorro y uso eficiente de energia en aires acondicionados mediante la proteccion solar

    Energy Technology Data Exchange (ETDEWEB)

    Mejia D, David; Morillon G, David; Rodriguez V, Luis [Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico)

    2001-07-01

    In here it is presented the analysis of the impact of the solar gains through the transparent parts of a prototype house of social interest, located in a dry warm climate. This analysis was made to determine the gains through windows for the summer time and under the following conditions: without outside solar protections, with the use of eaves, solar breakers and finally with the use of both systems of solar protection. The results were compared to obtain the considered potential of energy saving in cooling equipment, that could be obtained in future houses to build. [Spanish] Se presenta el analisis del impacto de las ganancias solares a traves de las partes transparentes de un prototipo de vivienda de interes social, ubicado en un clima calido seco. Dicho analisis se realizo para determinar las ganancias a traves de ventanas para la epoca de verano y bajo las siguientes condiciones: sin protecciones solares exteriores, con el empleo de aleros, con quiebrasoles y finalmente con el empleo de ambos sistemas de proteccion solar. Se compararon los resultados para obtener el potencial estimado de ahorro de energia en equipo de enfriamiento, que se tendria en las futuras viviendas por construir.

  6. Plan de negocio empresa aire acondicionado y ventilación mecánica Cooler Ingeniería

    OpenAIRE

    Espinel Ramírez, Christian David; Romero León, Oscar Fernando

    2013-01-01

    Este trabajo consiste en el plan de negocios de una empresa dedicada a la consultoría, diseño, instalación y venta de sistemas de aire acondicionado y ventilación mecánica llamada Cooler Ingeniería. Los objetivos principales del plan de negocios buscan identificar los servicios y productos que se ofrecerán en el portafolio de la compañía, definir las estrategias de mercado y conocer el monto de la inversión requerida para ser una empresa competitiva y rentable.

  7. Saving 50% of energy in air conditioning and refrigeration; 50% de ahorro de energia en aire acondicionado y refrigeracion

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez De la Fuente, Rodolfo Javier [Instituto para la Proteccion Ambiental de Nuevo Leon-CAINTRA, Nuevo Leon (Mexico); Bolado Tamez, Jaime Antonio [Industrias AlEn S. A. de C. V., Monterrey (Mexico)

    1998-12-31

    Due to the fact that the air conditioning systems represent up to 70% of the energy consumption in our buildings, to the constant raise of the electric tariffs and to the increment of temperatures in Nuevo Leon State, as well as the restrictions on the use of some refrigerant fluids because of its potential damage to the ozone layer (Montreal Protocol) and the preferential use of refrigerants with low global heating potential (Kioto Protocol). The Camara de la Industria de la Transformacion de Nuevo Leon (Nuevo Leon`s Transformation Industry Chamber) through the Instituto para la Proteccion Ambiental de Nuevo Leon (Nuevo Leon`s Institute for Environmental Protection), create the program ECO-REFRIGERATION whose three missions are: Increase the efficiency of air conditioning and refrigeration equipment, promote the substitution of refrigerants and extend the benefits of these projects to the community in general. [Espanol] Debido a que los sistemas de climatizacion representan hasta el 70% de consumo energetico en nuestros inmuebles, al constante incremento de las tarifas electricas, el incremento de las temperaturas en Nuevo Leon, asi como la restriccion del uso de algunos refrigerantes por su potencial de dano de la capa de ozono (Protocolo de Montreal) y el uso preferente de refrigerantes con bajo potencial de calentamiento global (Protocolo de Kioto), la Camara de la Industria de la Transformacion de Nuevo Leon a traves del Instituto para la Proteccion Ambiental de Nuevo Leon crean el Programa ECO-REFRIGERACION cuyas tres misiones son: Incrementar la eficiencia de los equipos de aire acondicionado y refrigeracion, promover la sustitucion de refrigerantes y extender los beneficios de este proyecto a la comunidad en general.

  8. Controlled environment laboratory for the energy certification of refrigeration and air conditioning systems; Laboratorio de ambiente controlado para la certificacion energetica de sistemas de refrigeracion y aire acondicionado

    Energy Technology Data Exchange (ETDEWEB)

    Ambriz, Juan Jose; Romero Paredes, Hernando; Dorantes, Ruben [Universidad Autonoma Metropolitana, Mexico, D.F. (Mexico)

    1999-07-01

    In this paper the general characteristics of the Controlled Environment Laboratory (CELAB) are described and some of the possible tests that could be performed in this device to evaluate the energy efficiency in air conditioning systems, domestic refrigeration and industrial refrigeration, as well as tests to evaluate the hydrothermal comfort in national populations, are presented. [Spanish] En este trabajo se describen las caracteristicas generales del Laboratorio de Ambiente Controlado (LAB), y se presentan algunas de las posibles pruebas que podran ser desarrolladas en este dispositivo para evaluar la eficiencia energetica en sistemas de aire acondicionado, refrigeracion domestica y refrigeracion industrial, asi como para pruebas para evaluar el confort hidrotermico en poblaciones nacionales.

  9. SESSA: Expert system for the selection of air conditioning equipment; SESEAA: Sistema experto para la seleccion de equipos de aire acondicionado

    Energy Technology Data Exchange (ETDEWEB)

    Kemper Valverde, Nicolas; Cardenas Perez, Edgar [Laboratorio de Sistemas Inteligentes, Centro de Instrumentos de la Universidad Nacional Autonoma de Mexico (UNAM), Mexico, D. F. (Mexico)

    1998-12-31

    The problem of selecting air conditioning and refrigeration equipment is quite wide and complex, since it encompasses from the application of the basic principles of physics and of thermodynamics up to the classic engineering design problems; these in turn can be numberless since they vary from place to place depending on multiple factors such as the region geographic and economic conditions. On the other hand, account most be taken of several elements such as windows, walls, and its specific geographical orientation, roofs, floors, partitions, equipment, lighting, etc., all this exerts influence in the complexity that represents the selection process. This paper describes a useful informatics tool to make it easy the selection process in air conditioning installations, taking into account multiple saving and efficient use of energy criteria, reflected in the operation process of these installations. [Espanol] El problema de seleccion de sistemas de aire acondicionado y de refrigeracion es bastante amplio y complejo, ya que abarca desde la aplicacion de los principios basicos de la fisica y la termodinamica hasta los problemas clasicos de diseno de ingenieria; estos a la vez pueden ser innumerables ya que varian de un lugar a otro y de un proyecto a otro, dependiendo de multiples factores tales como las condiciones geograficas y economicas de la region. Por otra parte se deben tomar en cuenta diversos elementos como son: ventanas, muros y sus orientaciones especificas, techos, pisos, particiones, equipos, iluminacion, etc., todo esto influye en la complejidad que representa el proceso de seleccion. En el presente trabajo se describe una herramienta informatica para facilitar el proceso de seleccion de instalaciones de aire acondicionado, tomando en cuenta multiples criterios de ahorro y uso eficiente de energia que se reflejan durante el proceso de operacion de estas instalaciones.

  10. Energy saving by means of air conditioning equipment replacement and the household application of thermal insulation; Ahorro de energia electrica por reemplazo de equipos de aire acondicionado y aplicacion de aislamiento termico en viviendas

    Energy Technology Data Exchange (ETDEWEB)

    Peralta Solorio, Jose Luis [Fideicomiso para el Ahorro de la Energia (Mexico)

    2005-07-15

    An extension study of the Financing Program for Energy Saving looked for the evaluation of the electric energy saving potential obtained by the replacement of air conditioning equipment and the application of thermal insulation in 30 houses of two Mexican cities with warmth climate. In a joint effort with Comision Federal de Electricidad the consumption files of the users were analyzed and field measurements of electric demand and of refrigeration were made. As a following step the change of the refrigeration necessities derived from the application of thermal insulation were evaluated as well as the energy efficiency improvement obtained by the substitution of the air conditioning equipment and the favorable results obtained by the implementation of both measures - thermal insulation and change of air conditioning equipment in a joint form. This way, as a conclusion, the optimum sequence of application of these measures is revealed. [Spanish] Un estudio extension del Programa de Financiamiento para el Ahorro de Energia Electrica busco evaluar el potencial de ahorro de energia electrica alcanzado por el reemplazo de equipos de aire acondicionado y la aplicacion de aislamiento termico en 30 viviendas de dos ciudades mexicanas con clima calido. En un esfuerzo conjunto con la Comision Federal de Electricidad se analizaron los historiales de consumo de los usuarios y se efectuaron las mediciones de campo de demanda electrica y de refrigeracion. Como paso siguiente se valoro el cambio en las necesidades de refrigeracion derivado de la aplicacion de aislamiento termico al igual que la mejora en eficiencia energetica obtenida por la sustitucion de aire acondicionado y se identificaron los resultados favorecedores arrojados por la implementacion de ambas medidas -aislamiento termico y cambio de equipo de aire acondicionado- en forma conjunta. De esta manera, como conclusion, se devela la mas optima secuencia de aplicacion de estas medidas.

  11. Evaluation of energy saving in pilot projects of window type air conditioning equipment in the domestic sector; Evaluacion del ahorro de energia en proyectos pilotos en equipos de aire acondicionado tipo ventana en el sector domestico

    Energy Technology Data Exchange (ETDEWEB)

    Duran Ramirez, Ricardo [Comision Nacional para el Ahorro de Energia, Mexico, D.F. (Mexico)

    2001-07-01

    The present work shows the energy saving when replacing low efficiency window type air conditioning equipment, for higher efficiency equipment, as well as the necessary parameters to identify the results obtained by the pilot projects of substitution of conventional equipment for other more efficient in the domestic sector. [Spanish] El presente trabajo muestra los ahorros de energia al sustituir equipos de aire acondicionado tipo ventana de baja eficiencia, por equipos de mayor eficiencia, asi como los parametros necesarios para identificar los resultados obtenidos, por los proyectos pilotos de sustitucion de equipos convencionales por otros mas eficientes en el sector domestico.

  12. Rational use of energy in air conditioning equipment, through an appropriate selection of the main equipment; Uso racional de la energia en equipos de aire acondicionado, mediante la eleccion apropiada del equipo principal

    Energy Technology Data Exchange (ETDEWEB)

    Reyes Zuniga, Jose de Jesus; Herrera Ramos, Manuel [Instituto Mexicano del Petroleo (Mexico)

    1996-07-01

    This paper presents an analysis to diminish the consumption of energy in central air conditioning equipment through an appropriate selection of the equipment. The analysis shows the levels of security and toxicity of the refrigerant, the operational, constructive and economic advantages of the equipment, taking as reference the cooling demand and expenses of energy consumption, as well as the ecological impact derived from the use of the refrigerant. Finally, an economic analysis is presented, involving the expenses of the equipment, operation, maintenance, costs of the consumption of used fluids, et cetera. [Spanish] Uso racional de la energia en equipos de aire acondicionado, mediante la eleccion apropiada del equipo principal. Este trabajo presenta un analisis para disminuir el consumo de energia en los equipos centrales de aire acondicionado mediante la seleccion apropiada del equipo. El analisis muestra los niveles de seguridad y toxicidad del refrigerante, las ventajas operativas, constructivas y economicas del equipo, tomando como referencia la demanda de enfriamiento y gastos de consumo de energia, asi como el impacto ecologico derivado de su empleo del refrigerante. Finalmente, se presenta un analisis economico, involucrando los gastos del equipo, operacion, mantenimiento, costos de consumos de fluidos utilizados, etcetera.

  13. Dimensionamiento montaje y análisis de funcionamiento de una instalación de aire acondicionado basado en un sistema solar térmico y una máquina de absorción de pequeña potencia

    OpenAIRE

    Martínez Sánchez, Rafael

    2008-01-01

    El objeto de este proyecto incluye el dimensionamiento, montaje, explotación y monitorización de una instalación de producción de frío con energía solar térmica y una máquina de absorción. La instalación solar térmica estará destinada a: • Abastecimiento de las necesidades de refrigeración en verano. • Abastecimiento de las necesidades de calefacción en invierno. El aprovechamiento térmico de la energía solar incidente, conllevará una importante disminución del consumo de...

  14. Connectable solar air collectors

    Energy Technology Data Exchange (ETDEWEB)

    Oestergaard Jensen, S.; Bosanac, M.

    2002-02-01

    The project has proved that it is possible to manufacture solar air collector panels, which in an easy way can be connected into large collector arrays with integrated ducting without loss of efficiency. The developed connectable solar air collectors are based on the use of matrix absorbers in the form of perforated metal sheets. Three interconnected solar air collectors of the above type - each with an transparent area of approx. 3 m{sup 2} - was tested and compared with parallel tests on two single solar air collectors also with a transparent area of approx. 3 m{sup 2} One of the single solar air collectors has an identical absorber as the connectable solar air collectors while the absorber of the other single solar air collector was a fibre cloth. The efficiency of the three solar air collectors proved to be almost identical in the investigated range of mass flow rates and temperature differences. The solar air collectors further proved to be very efficient - as efficient as the second most efficient solar air collectors tested in the IEA task 19 project Solar Air Systems. Some problems remain although to be solved: the pressure drop across especially the connectable solar air collectors is too high - mainly across the inlets of the solar air collectors. It should, however, be possible to considerably reduce the pressure losses with a more aerodynamic design of the inlet and outlet of the solar air collectors; The connectable solar air collectors are easy connectable but the air tightness of the connections in the present form is not good enough. As leakage leads to lower efficiencies focus should be put on making the connections more air tight without loosing the easiness in connecting the solar air collectors. As a spin off of the project a simple and easy way to determine the efficiency of solar, air collectors for pre-heating of fresh air has been validated. The simple method of determining the efficiency has with success been compared with an advance method

  15. Development of a electrothermal model to scale to determine the energy behavior in buildings with air conditioning; Desarrollo de un modelo electrotermico a escala para determinar el comportamiento energetico en edificaciones con aire acondicionado

    Energy Technology Data Exchange (ETDEWEB)

    Acoltzi, Higinio [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico)

    2001-07-01

    determinar el comportamiento energetico de modulos de prueba a escala de edificios. El modelo determina la historia del consumo de energia electrica para mantener la condiciones de confort al interior de los modulos, respecto a la variacion de los materiales de los techos y ventanas; todo esto con el objeto de establecer criterios de aplicacion de dichos materiales en la industria de la edificacion. Se presenta los consumos de energia electrica para los modulos con techos de loza monolitica, vigueta y clabovedilla y ventanas con vidrios reflectasol, filtrasol y claro. Finalmente, se presentan los resultados preliminares de la aplicacion del modelo propuesto a un edificio de escala normal. Las mediciones en campo y el modelo electrotermico teorico desarrollado, presenta diferencias promedio de 16%. Los ahorros de energia electrica observados con la aplicacion del modelo electrotermico teorico son: 1) si se cambia el vidrio claro por vidrio filtrasol, se pueden lograr ahorros de energia hasta del 14.5% para la loza de vigueta y bovedilla y de 12.4% para la loza monolitica; o 2) si se cambia el vidrio claro por vidrio reflectasol se pueden obtener ahorros de energia hasta de 28.1% para el caso de loza de vigueta y bovedilla y de 16.8% para la loza monolitica. La mejor opcion es sustituir la loza monolitica y vidrio claro por la loza de vigueta y bovedilla y vidrio reflectasol para obtener hasta un 37% de ahorro. Se muestra el arreglo de dispositivo experimental con los 3 modulos acoplados al aire acondicionado, y una con paracion grafica entre el consumo de energia acumulada teorica y experimental del modulo con loza de vigueta y bovedilla para los vidrios reflectasol, filtrasol y claro. Se da un resumen de los consumos de energia electrica totales.Verificacion experimental para determinar el comportamiento energetico de modulos de prueba a escala de edificios. El modelo determina la historia del consumo de energia electrica para mantener la condiciones de confort al interior

  16. Development of a electrothermal model to scale to determine the energy behavior in buildings with air conditioning; Desarrollo de un modelo electrotermico a escala para determinar el comportamiento energetico en edificaciones con aire acondicionado

    Energy Technology Data Exchange (ETDEWEB)

    Acoltzi, Higinio [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico)

    2001-07-01

    determinar el comportamiento energetico de modulos de prueba a escala de edificios. El modelo determina la historia del consumo de energia electrica para mantener la condiciones de confort al interior de los modulos, respecto a la variacion de los materiales de los techos y ventanas; todo esto con el objeto de establecer criterios de aplicacion de dichos materiales en la industria de la edificacion. Se presenta los consumos de energia electrica para los modulos con techos de loza monolitica, vigueta y clabovedilla y ventanas con vidrios reflectasol, filtrasol y claro. Finalmente, se presentan los resultados preliminares de la aplicacion del modelo propuesto a un edificio de escala normal. Las mediciones en campo y el modelo electrotermico teorico desarrollado, presenta diferencias promedio de 16%. Los ahorros de energia electrica observados con la aplicacion del modelo electrotermico teorico son: 1) si se cambia el vidrio claro por vidrio filtrasol, se pueden lograr ahorros de energia hasta del 14.5% para la loza de vigueta y bovedilla y de 12.4% para la loza monolitica; o 2) si se cambia el vidrio claro por vidrio reflectasol se pueden obtener ahorros de energia hasta de 28.1% para el caso de loza de vigueta y bovedilla y de 16.8% para la loza monolitica. La mejor opcion es sustituir la loza monolitica y vidrio claro por la loza de vigueta y bovedilla y vidrio reflectasol para obtener hasta un 37% de ahorro. Se muestra el arreglo de dispositivo experimental con los 3 modulos acoplados al aire acondicionado, y una con paracion grafica entre el consumo de energia acumulada teorica y experimental del modulo con loza de vigueta y bovedilla para los vidrios reflectasol, filtrasol y claro. Se da un resumen de los consumos de energia electrica totales.Verificacion experimental para determinar el comportamiento energetico de modulos de prueba a escala de edificios. El modelo determina la historia del consumo de energia electrica para mantener la condiciones de confort al interior

  17. Solar air-conditioning. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    Within the 3rd International Conference on solar air-conditioning in Palermo (Italy) at 30th September to 2nd October, 2009 the following lectures were held: (1) Removal of non-technological barriers to solar cooling technology across Southern European islands (Stefano Rugginenti); (2) The added economic and environmental value of solar thermal systems in microgrids with combined heat and power (Chris Marney); (3) Australian solar cooling interest group (Paul Kohlenbach); (4) Designing of a technology roadmap for solar assisted air conditioning in Austria (Hilbert Focke); (5) Solar cooling in the new context of renewable policies at European level (Raffaele Piria); (6) Prototype of a solar driven steam jet ejector chiller (Clemens Pollerberg); (7) New integrated solar air conditioning system (Joan Carlos Bruno); (8) Primary energy optimised operation of solar driven desiccant evaporative cooling systems through innovative control strategies; (9) Green chiller association (Uli Jakob); (10) Climate Well {sup registered} (Olof Hallstrom); (11) Low capacity absorption chillers for solar cooling applications (Gregor Weidner); (12) Solar cooling in residential, small scale commercial and industrial applications with adsorption technology (Walter Mittelbach); (13) French solar heating and cooling development programme based on energy performance (Daniel Mugnier); (14) Mirrox fresnel process heat collectors for industrial applications and solar cooling (Christian Zahler); (15) Modelling and analyzing solar cooling systems in polysun (Seyen Hossein Rezaei); (16) Solar cooling application in Valle Susa Italy (Sufia Jung); (17) Virtual case study on small solar cooling systems within the SolarCombi+Project (Bjoern Nienborg); (18) Design of solar cooling plants under uncertainty (Fernando Dominguez-Munoz); (19) Fast pre-design of systems using solar thermally driven chillers (Hans-Martin Henning); (20) Design of a high fraction solar heating and cooling plant in southern

  18. Energy saving: optimal use of air conditioning equipment by means of the solar control; Ahorro de energia: uso optimo de los acondicionadores de aire mediante el control solar

    Energy Technology Data Exchange (ETDEWEB)

    Mejia D, David; Morillon G, David; Rodriguez V, Luis [Universidad Nacional Autonoma de Mexico (Mexico)

    2001-09-01

    In this article the evaluation of the solar heat gains through the transparent parts of a building (houses of social interest) is presented; with the purpose of determining the heat gains through windows during summer time and under the following conditions: without solar protection, with the use of eaves, solar breakers and, finally, with the use of both elements. With the determined percentage of the diminution of heat gains, the considered potential of energy saving in air conditioning was obtained that would be available if the houses were constructed with solar control. [Spanish] En este articulo se presenta la evaluacion de las ganancias de calor solar a traves de las partes transparentes de un edificio (viviendas de interes social); con el objeto de determinar las ganancias de calor a traves de ventanas para la epoca de verano y bajo las siguientes condiciones: sin proteccion solar, con el empleo de aleros, con quiebrasoles y, finalmente, con el empleo de ambos elementos. Con el porcentaje determinado de la disminucion de ganancias de calor, se obtuvo el potencial estimado de ahorro de energia en aire acondicionado que se tendria si las viviendas se construyen con control solar.

  19. Heat pumping using the thermal earth gradient to produce air conditioned and hot water with savings of up to 70%; Bombeo de calor utilizando el gradiente termico de la tierra para producir aire acondicionado y agua caliente con ahorros de hasta un 70%

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez Ramirez, Alejandro [Novaenergia de Mexico S.A. de C.V. (Mexico)

    2003-07-01

    The pumping of heat using the Earth heat as partial energy source bases its principle on which the energy of the ground is constant and the energy efficiency to produce air conditioning and hot water simultaneously is important, obtaining savings up to 70%, comparing itself with the traditional equipment and what these operate of separated way to produce each one of them the cold air and the hot water. The use of this technology presents an opportunity to reduce the energy costs of and the demand of the company. [Spanish] El bombeo de calor utilizando el calor de la tierra como fuente parcial de energia basa su principio en que la energia del suelo es constante y el rendimiento energetico para producir simultaneamente aire acondicionado y agua caliente es importante, obteniendose ahorros hasta de un 70%, comparandose con los equipos tradicionales y que estos operan de manera separada para producir cada uno de ellos el aire frio y el agua caliente. El uso de esta tecnologia presenta una oportunidad para reducir los costos de energia y demanda de la empresa.

  20. Solar air conditioning. Dresden colloquium; Solare Klimatisierung. Dresdner Kolloquium

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    Subjects: R + D activities in solar air conditioning; dessicative and evaporative cooling (DEC) - systems and components; Chances of solar air conditioning in Europe; Practical experience with solar-assisted air conditioning; Performance of a solar system at Lissabon; DEC system in the Alsenblock building, Berlin; Does solar air conditioning require specially designed buildings; Performance of solar heated adsorption refrigerators; Low-capacity absacity absorption systems for solar air conditioning. [German] Die Kolloquiumsschrift beinhaltet Unterlagen ueber die abgehandelten Themen. Sie lauten: F and E-Aktivitaeten im Bereich Solare Klimatisierung; SGK(DEC-Technik) - ausgefuehrte Anlagen und deren Komponenten; Chancen der solaren Klimatisierung in Europa; Erfahrungen mit der solarunterstuetzten Klimatisierung; Energieverbrauch und Regelung von SGK-Anlagen; Betriebserfahrungen einer Solaranlage in Lissabon; Realisierung der SGK im Alsenblock Berlin; Erfordert die solare Klimatisierung besondere Gebaeude?; Betriebserfahrungen mit solar beheizten Adsorptionskaeltemaschinen; Absorptionsanlagen kleiner Leistung fuer solare Klimatisierung. (orig.)

  1. Solar air heaters and their applications

    Science.gov (United States)

    Selcuk, M. K.

    1977-01-01

    The solar air heater appears to be the most logical choice, as far as the ultimate application of heating air to maintain a comfortable environment is concerned. One disadvantage of solar air heaters is the need for handling larger volumes of air than liquids due to the low density of air as a working substance. Another disadvantage is the low thermal capacity of air. In cases where thermal storage is needed, water is superior to air. Design variations of solar air heaters are discussed along with the calculation of the efficiency of a flat plate solar air heater, the performance of various collector types, and the applications of solar air heaters. Attention is given to collectors with nonporous absorber plates, collectors with porous absorbers, the performance of flat plate collectors with finned absorbers, a wire mesh absorber, and an overlapped glass plate air heater.

  2. Experimental Analysis on Solar Desiccant Air Conditioner

    Directory of Open Access Journals (Sweden)

    Dr. U. V. Kongre, C. M. Singh, A. B. Biswas

    2014-05-01

    Full Text Available The experiment investigated and evaluated the feasibility of an solar desiccant air conditioner. Its effectiveness as a possible air conditioner option used in household air conditioner or as an energy efficient and environmentally friendly alternative to conventional air conditioning units used in houses are evaluated. A solar water heater was used as heat gain. The model utilizes the technology of solar air conditioner system. The purpose in the long term would be reduced the consumption of electricity used for air conditioning, reduce harmful emission and hence saving money.

  3. Application of a solar refrigeration system by absorption for the air conditioning of buildings

    Energy Technology Data Exchange (ETDEWEB)

    Machielsen, Cees H. M [Delft University of Technology, Mekelweg (Netherlands); Hagendijk, Andre E [Consultancy and Research (Netherlands)

    2000-07-01

    This paper describes the Sofri project, a cooperation between Ceeran Ltd and The Delft University of Technology. The main objective of this project is to develop the necessary knowledge and experience to commercialize solar-assisted air conditioning and dehumidification systems in the Dutch Caribbean. The project is motivated by the present needs of the Dutch Caribbean for renewable energy sources and the fact that the Caribbean has a high and uniform insolation throughout the year. Furthermore, hotels and offices in this area use more than 40% of their energy for air-conditioning purposes. Therefore solar-assisted air conditioning systems are a logic approach in reducing the energy demand and to lower the peak electricity reducing the energy demands for the local power station. Ceeran Ltd has the objective to reach full commercialization of the proposed technologies in the Dutch Caribbean. The research is concentrated on liquid absorption machines and solar collection systems such as flat plates with selective surfaces, heat pipe evacuated tubes flat plate collectors, and Compound Parabolic Concentrators. The first demonstration unit is planned to be installed in an office building in Curacao. The installation consists of a 35 kW LiBr/H{sub 2}O absorption machine driven by 100 m{sup 2} flat pate collectors with a gas backup system. The system will provide comfort air-conditioning for this these type of office buildings during daytime. [Spanish] Este documento describe el proyecto SOFRI, una cooperacion entre Ceeran, Ltd, y la Universidad Tecnologica del Delft. El principal objetivo de este proyecto es el de desarrollar el conocimiento necesario y la experiencia para comercializar los sistemas de aire acondicionado y deshumidificacion ayudados por la energia solar en el Caribe Holandes. Este proyecto ha sido motivado por las actuales necesidades del Caribe Holandes de fuentes de energia renovable y por el hecho de que el Caribe tiene una alta y uniforme insolacion

  4. Air leakage in residential solar heating systems

    Science.gov (United States)

    Shingleton, J. G.; Cassel, D. E.; Overton, R. L.

    1981-02-01

    A series of computer simulations was performed to evaluate the effects of component air leakage on system thermal performance for a typical residential solar heating system, located in Madison, Wisconsin. Auxiliary energy required to supplement solar energy for space heating was determined using the TRNSYS computer program, for a range of air leakage rates at the solar collector and pebble bed storage unit. The effects of heat transfer and mass transfer between the solar equipment room and the heated building were investigated. The effect of reduced air infiltration into the building due to pressurized by the solar air heating system were determined. A simple method of estimating the effect of collector array air leakage on system thermal performance was evaluated, using the f CHART method.

  5. A Review of Solar Desiccant Air Conditioner

    Directory of Open Access Journals (Sweden)

    Dr. U. V. Kongre, D. P. Mahure, P. A. Zamre

    2014-04-01

    Full Text Available This paper represents a detailed study and description of a new solar-based air-conditioning technique. It uses solar energy to produce cold or hot air. This technology can be used to reduce the energy consumption and environmental impact of mechanical cooling system. The use of Desiccant cooling is used to perform air dehumidification operation by utilizing low grade heat source. The solar desiccant air conditioner uses solar power as the main energy source to help in the thermodynamic heat transfer process as well as heat transfer principles to convert ambient air into cooling air. With our constructed design we have seen temperature as well as humidity level drops throughout the desiccant cooling system. A significant advantage of this system is, it have no moving parts consequently they are noiseless, non-corrosive, cheap to maintain, long lasting in addition to being environmentally friendly with zero ozone depletion as well as zero global warming potentials.

  6. Movable air solar collector and its efficiency

    International Nuclear Information System (INIS)

    Implementing the guidelines of the Latvian National Programme for Energy in the field of alternative energy, intensive research shall be carried on regarding the use of solar energy, as it can be successfully used not only for the purposes of water heating and production of electrical energy, but also for air warming. The amount of heat necessary for the drying of rough forage and grain drying by active aeration in June, July and August can be obtained using solar radiation. The Latvian Guidelines for the Energy Development 2006-2016 state that the solar radiance in Latvia is of quite low intensity. The total amount of solar energy is 1109 kWh m-2 per year. The period of usage of the solar thermal energy is beginning from the last decade of April, when the intensity of radiation is 120 kWh m-2, until the first decade of September. Within this period (approximately 1800 hours), it is possible to use the solar thermal energy by placing solar collectors. The usage of solar collectors for in drying of agricultural production is topical from the viewpoint of decreasing the consumption of energy used for the drying, as electrical energy and fossil energy resources become more expensive and tend to run out. In the processes that concern drying of agricultural production, efficiently enough solar radiation energy can be used. Due to this reason researching continues and expands in the field of usage of solar energy for the processes of drying and heating. The efficiency factor of the existing solar collectors is not high, but they are of simple design and cheep for production and exploitation. By improving the design of the solar collectors and choosing modern materials that absorb the solar radiation energy, it is possible the decrease the efficiency factor of solar collectors and decrease the production costs. In the scientific laboratory of grain drying and storage of Latvia University of Agriculture, a pilot device movable folding solar collector pilot device suitable

  7. Improving Air Quality with Solar Energy

    Science.gov (United States)

    2008-04-01

    This fact sheet series highlights how renewable energy and energy efficiency technologies can and are being used to reduce air emissions and meet environmental goals, showcasing case studies and technology-specific topics. This one focus on solar energy technologies.

  8. Solar Air Heaters with Thermal Heat Storages

    Directory of Open Access Journals (Sweden)

    Abhishek Saxena

    2013-01-01

    Full Text Available Solar energy can be converted into different forms of energy, either to thermal energy or to electrical energy. Solar energy is converted directly into electrical power by photovoltaic modules, while solar collector converts solar energy into thermal energy. Solar collector works by absorbing the direct solar radiation and converting it into thermal energy, which can be stored in the form of sensible heat or latent heat or a combination of sensible and latent heats. A theoretical study has been carried out to rate the various thermal energy storage commonly used in solar air heaters. During the investigations rock bed storages have been found to be low type thermal heat storage, while phase change materials have been found to be high heat thermal storages. Besides this, a few other heat storing materials have been studied and discussed for lower to higher ratings in terms of thermal performance purposely for solar heaters.

  9. Solar Powered Radioactive Air Monitoring Stations

    Energy Technology Data Exchange (ETDEWEB)

    Barnett, J. Matthew; Bisping, Lynn E.; Gervais, Todd L.

    2013-10-30

    Environmental monitoring of ambient air for radioactive material is required as stipulated in the PNNL Site radioactive air license. Sampling ambient air at identified preferred locations could not be initially accomplished because utilities were not readily available. Therefore, solar powered environmental monitoring systems were considered as a possible option. PNNL purchased two 24-V DC solar powered environmental monitoring systems which consisted of solar panels, battery banks, and sampling units. During an approximate four month performance evaluation period, the solar stations operated satisfactorily at an on-site test location. They were subsequently relocated to their preferred locations in June 2012 where they continue to function adequately under the conditions found in Richland, Washington.

  10. Solar powered absorption air conditioning

    Science.gov (United States)

    Vardon, J. M.

    1980-04-01

    Artificial means of providing or removing heat from the building are discussed along with the problem of the appropriate building design and construction for a suitable heat climate inside the building. The use of a lithium bromide-water absorption chiller, powered by a hot water store heated by an array of stationary flat collectors, is analyzed. An iterative method of predicting the cooling output from a LiBr-water absorption refrigeration plant having variable heat input is described and a model allowing investigation of the performance of a solar collector and thermal storage system is developed.

  11. The effects of air leaks on solar air heating systems

    Science.gov (United States)

    Elkin, R.; Cash, M.

    1979-01-01

    This paper presents the results of an investigation to determine the effects of leakages in collector and duct work on the system performance of a typical single-family residence solar air heating system. Positive (leakage out) and negative (leakage in) pressure systems were examined. Collector and duct leakage rates were varied from 10 to 30 percent of the system flow rate. Within the range of leakage rates investigated, solar contribution to heated space and domestic hot water loads was found to be reduced up to 30 percent from the no-leak system contribution with duct leakage equally divided between supply and return duct; with supply duct leakage greater than return leakage a reduction of up to 35 percent was noted. The negative pressure system exhibited a reduction in solar contribution somewhat larger than the positive pressure system for the same leakage rates.

  12. Determination of thermal performance of solar air heater

    OpenAIRE

    Kozak, Christina; Zhelykh, Vasil

    2013-01-01

    Considered the basic aspects of passive solar building. Given the main types of solar air heating systems. Proposed heating and ventilation system at the basis of solar air heater. Constructed fourfactors nomohram for determining thermal power of the thermosiphon heliocollector. Obtained analytical dependence of the amount heat of thermo heliocollector from the differential temprature air inlet and outlet, of the area input and output apertures of solar collector, heat fl...

  13. Solar technology assessment project. Volume 4: Solar air conditioning: Active, hybrid and passive

    Science.gov (United States)

    Yellott, J. I.

    1981-04-01

    The status of absorption cycle solar air conditioning and the Rankine cycle solar cooling system is reviewed. Vapor jet ejector chillers, solar pond based cooling, and photovoltaic compression air conditioning are also briefly discussed. Hybrid solar cooling by direct and indirect evaporative cooling, and dehumidification by desiccation are described and discussed. Passive solar cooling by convective and radiative processes, evaporative cooling by passive processes, and cooling with roof ponds and movable insulation are reviewed. Federal and state involvement in solar cooling is discussed.

  14. Solar supported air heating of existing factory buildings; Solar unterstuetzte Luftheizung von Industriehallen im Bestand

    Energy Technology Data Exchange (ETDEWEB)

    Lomachenko, Olga; Urbaneck, Thorsten; Platzer, Bernd [Technische Univ. Chemnitz (Germany). Fakultaet fuer Maschinenbau

    2011-01-15

    The use of solar heating systems for heating of factory buildings is not widely spread today. However, by using solar heating systems large quantities of energy could be saved. The studies on solar systems are primarily focused on design of solar heating systems for apartment heating. Air heating in combination with solar heating system was until today barely analyzed and optimized. Up to now there are almost no studies on combination of air heating with solar heating conducted. In this work a study of decentralized air heating of an existing factory building in combination with solar heating device is conducted. The study is based on numerical simulation with TRNSYS simulation program. (orig.)

  15. Solar Air Collectors: How Much Can You Save?

    Science.gov (United States)

    Newburn, J. D.

    1985-04-01

    A collector efficiency curve is used to determine the output of solar air collectors based on the testing of seven solar collectors sold in Iowa. In this application the solar heater is being used as a space heater for a house. The performance of the solar air heater was analyzed and an 8% savings in energy was achieved over a one year period using two 4 x 8 collectors in a typical house.

  16. Novel solar air Heater for high temperatures; Novedoso Calentador solar de aire para altas temperaturas

    Energy Technology Data Exchange (ETDEWEB)

    Rincon, E. A.; Duran, M. D.; Lentz, A. E.

    2008-07-01

    A novel solar air heater that allows to reach temperatures of the order of 100 degree centigrade with thermal efficiencies superior to 50% due to a solar concentrator and the reduction of thermal losses from the air when circulating between the absorber and mirrors of section of circular arc, well isolated of the outside surrounding. The receiver consists of a concentrator with wedges of plastic transparency that make the function of lenses. The light refracted by the wedges enters to a series of concentrators PC type truncated optimally so that the space among them allows the positioning of the absorber, who are covered metallic segments with selective film. Its excellent performance makes ideals applications as Sauna bath, the drying at high temperature, and systems for conditioning of air. (Author)

  17. Simulation of Solar Air-Conditioning System with Salinity Gradient Solar Pond

    OpenAIRE

    Safwan Kanan, Jonathan Dewsbury, Gregory Lane-Serff

    2015-01-01

    In hot dry climates, due to the high demand for space air conditioning during summer and the abundance of solar radiation, solar air conditioning is a promising approach to reduce the energy consumption and negative environmental impact of buildings. Solar cooling systems have used various types of collectors to drive chillers. In this paper, a salinity gradient solar pond is suggested as a collector to drive an absorption chiller, to provide cool air for a house during hot and dry weather. A...

  18. Design of direct solar PV driven air conditioner

    KAUST Repository

    Huang, Bin-Juine

    2015-12-05

    © 2015 Elsevier Ltd. Solar air conditioning system directly driven by stand-alone solar PV is studied. The air conditioning system will suffer from loss of power if the solar PV power generation is not high enough. It requires a proper system design to match the power consumption of air conditioning system with a proper PV size. Six solar air conditioners with different sizes of PV panel and air conditioners were built and tested outdoors to experimentally investigate the running probabilities of air conditioning at various solar irradiations. It is shown that the instantaneous operation probability (OPB) and the runtime fraction (RF) of the air conditioner are mainly affected by the design parameter rpL (ratio of maximum PV power to load power). The measured OPB is found to be greater than 0.98 at instantaneous solar irradiation IT > 600 W m-2 if rpL > 1.71 RF approaches 1.0 (the air conditioner is run in 100% with solar power) at daily-total solar radiation higher than 13 MJ m-2 day-1, if rpL > 3.

  19. Application of Solar Energy to Air Conditioning Systems

    Energy Technology Data Exchange (ETDEWEB)

    M, Nash J; J, Harstad A

    1976-11-01

    The results of a survey of solar energy system applications of air conditioning are summarized. Techniques discussed are both solar powered (absorption cycle and the heat engine/ Rankine cycle) and solar related (heat pump). Brief descriptions of the physical implications of various air conditioning techniques, discussions of status, proposed technological improvements, methods of utilization and simulation models are presented, along with an extensive bibliography of related literature.

  20. Solar Air Heaters with Thermal Heat Storages

    OpenAIRE

    Abhishek Saxena; Varun Goel

    2013-01-01

    Solar energy can be converted into different forms of energy, either to thermal energy or to electrical energy. Solar energy is converted directly into electrical power by photovoltaic modules, while solar collector converts solar energy into thermal energy. Solar collector works by absorbing the direct solar radiation and converting it into thermal energy, which can be stored in the form of sensible heat or latent heat or a combination of sensible and latent heats. A theoretical study has be...

  1. DESIGN a solar hybrid air conditioning compressor system

    OpenAIRE

    Khalaji Assadi M.; Gilani S. I.; Jun Yen T. C.

    2016-01-01

    To develop and integrate solar hybrid system into conventional air conditioning system which provides the same cooling load with considerably less electricity demand. Solar evacuated tube and DC compressor are used for compressing the refrigerant in an air conditioning system, thus effectively reducing the air conditioning electricity consumption by up to 45%. For the flow through type selected geometry of the designed evacuated U-tube collector, a three dimensional simulation and analysis of...

  2. DESIGN a solar hybrid air conditioning compressor system

    Directory of Open Access Journals (Sweden)

    Khalaji Assadi M.

    2016-01-01

    Full Text Available To develop and integrate solar hybrid system into conventional air conditioning system which provides the same cooling load with considerably less electricity demand. Solar evacuated tube and DC compressor are used for compressing the refrigerant in an air conditioning system, thus effectively reducing the air conditioning electricity consumption by up to 45%. For the flow through type selected geometry of the designed evacuated U-tube collector, a three dimensional simulation and analysis of the thermal performance was done, using the solar ray-tracing model provided by the ANSYS-FLUENT software.

  3. Desarrollo y aplicación del diagnóstico y pronóstico técnico al mantenimiento de los sistemas centralizados de aire acondicionado. // Develop and application of diagnosis and technical prediction to maintenance of centralized air conditioned systems.

    Directory of Open Access Journals (Sweden)

    J. L. Sánchez Ávila

    2001-10-01

    Full Text Available Se expone la aplicación del mantenimiento por diagnóstico y pronóstico técnico al sistema centralizado de aireacondicionado con recuperación del calor del hotel LTI Bella Costa; como solución a los graves problemas a que seenfrenta la dirección de servicios técnicos de las instalaciones turísticas para realizar un mantenimiento con calidad y a unmenor costo. El desarrollo de un plan experimental, en las instalaciones del hotel, permitió obtener las curvas que expresanel comportamiento de la degradación de estos sistemas en el tiempo, así como determinar el momento más oportuno para larealización del mantenimiento.La aplicación de esta investigación permitió la implementación de un mantenimiento menoscostoso y de más calidad, aumentando la rentabilidad de la labor del mantenimiento, y lo que es decisivo en este tipo deinstalación: la seguridad en la explotación como garantía de un servicio sin fallas.Palabras claves: Mantenimiento, refrigeración, predictivo, diagnóstico, pronóstico.___________________________________________________________________Abstract:The application of maintenance by diagnosis and technical prediction to centralized system of conditioned air withrecovery of heat is exposed; as solution to the serious problems faces technical services of tourist facilities to carry outmaintenance with quality and smaller cost. The development of an experimental plan, in hotel facilities, allowed to obtaincurves that express the behavior of degradation of these systems in time, as well as to determine the most opportunemoment for the maintenance realization. Application of this investigation allowed the implementation of a less expensivemaintenance with more quality, increasing the profitability of maintenance work, and what is decisive in this type ofinstallation,: the security in the exploitation like guarantee of a service without flaws.Key words. Maintenance, refrigeration, prediction, diagnosis, air conditioned.

  4. Experimental studies of a matrix-tubular solar air collector

    Energy Technology Data Exchange (ETDEWEB)

    Plesca, M.; Varlan, P. [Moldova Technical Univ., Chisinau (Moldova, Republic of). Dept. of Heat and Gas Supply and Ventilation

    2009-06-15

    The most common types of solar air collectors (SAC) are contact-type and matrix-type collectors, with the latter being more efficient. This paper described the design and testing of a matrix-tubular flat solar air collector in the city of Chisinau, Moldova, where the outdoor climatic radiation, heat, and humidity characteristics are favorable for the efficient use of solar energy for building heating and drying applications. The amount of solar energy absorbed by a solar energy air collector depends on the level of insulation and orientation of the solar collector; the absorbance of the absorber surface; and the transmittance of the cover material. This study examined the heat transfer, efficiency, and pressure drop using copper tubes inserted perpendicular to the plane of the absorber plate. The SAC consists of a glazed insulated case, an absorber, and ducting for cold air delivery and hot air discharge. Copper tubes are inserted perpendicular to the plane of the absorber. The absorber is installed in the body of the SAC in such a way that it divides it into an upper channel and lower channel. The channel bottom is lined with aluminium foil that reflects solar radiation coming through the tubes and decreases heat loss in the solar collector. Copper tubes increase the heat exchange surface, create air turbulence and intensify heat transfer. This increases the efficiency of the solar collector. The pressure drop of the matrix-tubular solar air collector is 40 per cent lower than that of the matrix-plate collectors. 11 refs., 2 tabs., 6 figs.

  5. Performance of artificially roughened solar air heaters. A review

    Energy Technology Data Exchange (ETDEWEB)

    Hans, Vishavjeet Singh [Department of Mechanical Engineering, PAU, Ludhiana, 141004, Punjab (India); Saini, R.P. [Alternate Hydro Energy Centre, Indian Institute of Technology, Roorkee, 247667, UK (India); Saini, J.S. [Mechanical and Industrial Engineering Department, Indian Institute of Technology, Roorkee, 247667, UK (India)

    2009-10-15

    The conversion, utilization and recovery of energy invariably involve a heat exchange process, which makes it imperative to design more efficient heat exchanger. The use of artificial roughness in different forms, shapes and sizes is the most common and effective way to improve the performance of a solar air heater. Several studies have been carried out to determine the effect of different roughness element geometries on heat transfer and friction in solar air heaters. This study reviews various roughness element geometries employed in solar air heaters for performance enhancement. Based on the correlations of heat transfer and friction factor developed by various investigators, an attempt has been made to compare the thermohydraulic performance of roughened solar air heaters. (author)

  6. Solar air conditioning researches and demonstrations in China

    Institute of Scientific and Technical Information of China (English)

    Wang Ruzhu

    2009-01-01

    This paper mainly shows the demonstration of solar air conditioning systems in China, which includes LiBr-H2O absorption cooling, silica gel-water adsorption chiller, desiccant cooling and hybrid integrated energy systems for buildings. The match of solar collector types and chiller types have been discussed and suggested.

  7. MATHEMATICAL MODELLING AND PERFORMANCE ANALYSIS OF DIFFERENT SOLAR AIR COLLECTORS

    Directory of Open Access Journals (Sweden)

    M. A. Karim

    2015-11-01

    Full Text Available The purpose of using solar air collectors is to raise the atmospheric air temperature to a temperature which can be used for various low and medium temperature applications. Collector, absorber and airflow arrangement are the most important components in the solar air collector. The performance of the collector depends on its heat loss and the absorber area that is in contact with the airflow. This study involves the theoretical simulation of the effect of mass flow rate on the performance, for flat plate and v-groove collectors that are in single and double pass configurations. Results show that the v-groove double pass air collector has the highest efficiency value of 56% at . The performance is greater than flat plate double pass collector, which has an efficiency of 54% under the same operating conditions. KEYWORDS: solar air collector; flat plate collector (fpc; v-groove collector; efficiency; single pass; double pass

  8. Solar air-conditioning-active, hybrid and passive

    Energy Technology Data Exchange (ETDEWEB)

    Yellott, J. I.

    1981-04-01

    After a discussion of summer air conditioning requirements in the United States, active, hybrid, and passive cooling systems are defined. Active processes and systems include absorption, Rankine cycle, and a small variety of miscellaneous systems. The hybrid solar cooling and dehumidification technology of desiccation is covered as well as evaporative cooling. The passive solar cooling processes covered include convective, radiative and evaporative cooling. Federal and state involvement in solar cooling is then discussed. (LEW)

  9. Humidification dehumidification desalination system using parabolic trough solar air collector

    International Nuclear Information System (INIS)

    This paper deals with a detailed thermodynamic analysis to assess the performance of an HDH system with an integrated parabolic trough solar collector (PTSC). The HDH system considered is an open air, open water, air heated system that uses a PTSC as an air heater. Two different configurations were considered of the HDH system. In the first configuration, the solar air heater was placed before the humidifier whereas in the second configuration the solar air heater was placed between the humidifier and the dehumidifier. The current study revealed that PTSCs are well suited for air heated HDH systems for high radiation location, such as Dhahran, Saudi Arabia. The comparison between the two HDH configurations demonstrates that the gained output ratio (GOR) of the first configuration is, on average, about 1.5 whereas for the second configuration the GOR increases up to an average value of 4.7. The study demonstrates that the HDH configuration with the air heater placed between the humidifier and the dehumidifier has a better performance and a higher productivity. - Highlights: • Thermodynamic analysis of an HDH system driven by a parabolic trough solar collector was conducted. • The first configuration reveals a GOR of 1.5 while the second configuration reveals a GOR of 4.7. • Effective heating of the HDH system was obtained through parabolic trough solar collector

  10. A solar air collector with integrated latent heat thermal storage

    OpenAIRE

    Klimes Lubomir; Mauder Tomas; Ostry Milan; Charvat Pavel

    2012-01-01

    Simulations of the behaviour of a solar air collector with integrated latent heat thermal storage were performed. The model of the collector was created with the use of coupling between TRNSYS 17 and MATLAB. Latent heat storage (Phase Change Material - PCM) was integrated with the solar absorber. The model of the latent heat storage absorber was created in MATLAB and the model of the solar air collector itself was created in TRNSYS with the use of TYPE 56. The model of the latent heat storage...

  11. A solar air collector with integrated latent heat thermal storage

    Science.gov (United States)

    Charvat, Pavel; Ostry, Milan; Mauder, Tomas; Klimes, Lubomir

    2012-04-01

    Simulations of the behaviour of a solar air collector with integrated latent heat thermal storage were performed. The model of the collector was created with the use of coupling between TRNSYS 17 and MATLAB. Latent heat storage (Phase Change Material - PCM) was integrated with the solar absorber. The model of the latent heat storage absorber was created in MATLAB and the model of the solar air collector itself was created in TRNSYS with the use of TYPE 56. The model of the latent heat storage absorber allows specification of the PCM properties as well as other parameters. The simulated air collector was the front and back pass collector with the absorber in the middle of the air cavity. Two variants were considered for comparison; the light-weight absorber made of sheet metal and the heat-storage absorber with the PCM. Simulations were performed for the climatic conditions of the Czech Republic (using TMY weather data).

  12. A solar air collector with integrated latent heat thermal storage

    Directory of Open Access Journals (Sweden)

    Klimes Lubomir

    2012-04-01

    Full Text Available Simulations of the behaviour of a solar air collector with integrated latent heat thermal storage were performed. The model of the collector was created with the use of coupling between TRNSYS 17 and MATLAB. Latent heat storage (Phase Change Material - PCM was integrated with the solar absorber. The model of the latent heat storage absorber was created in MATLAB and the model of the solar air collector itself was created in TRNSYS with the use of TYPE 56. The model of the latent heat storage absorber allows specification of the PCM properties as well as other parameters. The simulated air collector was the front and back pass collector with the absorber in the middle of the air cavity. Two variants were considered for comparison; the light-weight absorber made of sheet metal and the heat-storage absorber with the PCM. Simulations were performed for the climatic conditions of the Czech Republic (using TMY weather data.

  13. Evaluation of an air solar collector

    Science.gov (United States)

    1979-01-01

    Performance verification under simulated conditions tested by using Marshall Space Flight Center solar simulator is presented. Evaluation included thermal performance tests, time constant tests, and incident angle modifier tests.

  14. Feasibility of a solar-assisted winter air-conditioning system using evaporative air-coolers

    Directory of Open Access Journals (Sweden)

    Mohamed M. El-Awad

    2011-03-01

    Full Text Available The paper presents a winter air-conditioning system which is suitable for regions with mildly cold but dry winters. The system modifies the evaporative air-cooler that is commonly used for summer air-conditioning in such regions by adding a heating process after the humidification process. The paper describes a theoretical model that is used to estimate the system's water and energy consumption. It is shown that a 150-LPD solar heater is adequate for air-conditioning a 500 ft3/min (14.4 m3/min air flow rate for four hours of operation. The maximum air-flow rate that can be heated by a single solar water-heater for four hours of operation is about 900-cfm, unless a solar water heater large than a 250-LPD heater is used. For the 500 ft3/min air flow rate the paper shows that the 150, 200, 250 and 300 LPD solar water-heaters can provide air-conditioning for 4, 6, 8 and 10 hours, respectively, while consuming less energy than the equivalent refrigerated-type air-conditioner.

  15. Experimental study of a combined system of solar Kang and solar air collector

    International Nuclear Information System (INIS)

    Highlights: • A combined system of solar Kang and solar air collector is proposed. • An experimental study on the combined system is made. • The mean air temperature reaches 18.5 °C and maintains above 18 °C for 13 h. • The corresponding mean indoor air temperature of the reference room is 8.9 °C. • The Kang surface temperature reaches 27 °C and maintains above 18 °C for 23 h. - Abstract: Chinese Kang is widely used as heated bed and for heat recovery of cooking stove in Northern China. However there are main drawbacks of indoor and outdoor air pollutant generation and heavy demands on solid fuel handling. A novel combined Kang system, which integrates solar Kang and solar air collector, is here proposed. Experiments were conducted to examine the alternative operating modes: (i) only solar air collector in service, (ii) only solar Kang in service, and (iii) both solar Kang and solar air collector in service. The results show that these three modes behave differently and have distinct effects on room thermal environment in winter. When this pollution-free system operates under the third combined mode, the room temperature increases significantly and the vertical temperature gradient reduces. The Kang surface temperature increases and its uniformity is improved. It is also found that the room air temperature is closely related to the Kang surface temperature. Furthermore, most of the time the thermal environment meets the occupant need. This paper reports the experimental work and investigates into the effects on indoor thermal environment as in rural residences in Northern China

  16. Improving Air Quality with Solar Energy

    Energy Technology Data Exchange (ETDEWEB)

    None

    2008-04-01

    This fact sheet series highlights how renewable energy and energy efficiency technologies can and are being used to reduce air emissions and meet environmental goals, showcasing case studies and technology-specific topics.

  17. Performance of cylindrical plastic solar collectors for air heating

    International Nuclear Information System (INIS)

    Highlights: • The study including the combined convective and radiative heat transfer analysis. • The solar collector is manufactured from LDPE films acting as a black absorber. • Comparisons between the experimental data and the theoretical methods have been made. • The thermal efficiency increases with decreasing the major axes of elliptic shape. • The Nusselt number between the absorber and the heated air is determined. - Abstract: A theoretical and experimental study including the combined convective and radiative heat transfer analysis of a flexible cylindrical type solar air-heater for agriculture crops dehydration as well as heating processes is presented. The solar collector is manufactured from LDPE films acting as a black absorber with a back insulation and double transparent covers sealed together along its edges. The collector is to be blown with a flow of pressurized air. The experiments are carried out with solar collectors of circular shapes having 0.5 m diameter and solar collectors of elliptic shapes having 0.55 m and 0.65 m major axis. Energy balance of the cover, absorber and air yield three simultaneous quadratic algebraic equations in the three unknowns namely, cover, absorber and outlet air temperatures. A computer program is written for calculating the outlet temperature using the Newton–Raphson method and the collector thermal efficiency in terms of its diameter, length, mass flow rate, inlet temperature and solar insolation. Moreover the Nusselt number between the absorber and the heated air is determined experimentally in relation with the Reynolds number. Comparisons between the experimental data and the theoretical methods for the collector efficiency demonstrate a good agreement. In addition of this, the present experimental results of Nusselt number are correlated and compared with a correlation of another authors

  18. Performance evaluation of an air solar collector

    Science.gov (United States)

    1979-01-01

    Indoor tests on signal-glazed flat-plate collector are described in report. Marhsall Space Flight Center solar simulator is used to make tests. Test included evaluations on thermal performance under various combinations of flow rate, incident flux, inlet temperature, and wind speed. Results are presented in graph/table form.

  19. Development of solar driven absorption air conditioners and heat pumps

    Science.gov (United States)

    Dao, K.; Wahlig, M.; Wali, E.; Rasson, J.; Molishever, E.

    1980-03-01

    The development of absorption refrigeration systems for solar active heating and cooling applications is discussed. The approaches investigated are those using air-cooled condenser-absorber and those leading to coefficient of performances (COP) that increase continuously with heat source temperature. This is primarily an experimental project, with the emphasis on designing, fabricating and testing absorption chillers in operating regimes that are particularly suited for solar energy applications. Its demonstrated that the conventional single-effect ammonia-water absorption cycle can be used (with minor modifications) for solar cooling.

  20. Solar Park Impacts on Air and Soil Microclimate

    Science.gov (United States)

    Armstrong, A.; Ostle, N. J.; Whitaker, J.

    2015-12-01

    The drive towards low carbon energy sources and increasing energy demand has resulted in a rapid rise in solar photovoltaics across the world. A substantial proportion of photovoltaics are large-scale ground-mounted systems, solar parks, causing a notable land use change. While the impacts of photovoltaic panel production and disposal have been considered, the consequences of the operation of solar parks on the hosting landscape are poorly resolved. Here, we present data which demonstrates that a solar park sited on permanent grassland in the UK significantly impacted the air and soil microclimate. Specifically, we observed (1) cooler soil under the photovoltaic panels during the summer and between the photovoltaic panel rows during the winter; (2) dampening of the diurnal variation in air temperature and absolute humidity from the spring to the autumn; (3) lower photosynthetically active radiation and a lower direct:diffuse under the panels; and (4) reduced wind speed between the panel rows and substantially reduced wind speeds under the panels. Further, there were differences in vegetation type and productivity and greenhouse gas emissions. Given the centrality of climate on ecosystem function, quantifying the microclimatic impacts of this emerging land use change is critical. We anticipate these data will help develop understanding of effects in other climates, under different solar park designs and the implications for the function and service provision of the hosting landscape.

  1. Desarrollo y aplicación del diagnóstico y pronóstico técnico al mantenimiento de los sistemas centralizados de aire acondicionado // Develop and application of the diagnosis and technical prediction to the maintenance of the centralized systems of conditi

    Directory of Open Access Journals (Sweden)

    J. L. Sánchez Ávila

    2000-10-01

    Full Text Available Se expone la aplicación del mantenimiento por diagnóstico y pronóstico técnico al sistema centralizado de aireacondicionado con recuperación del calor del hotel LTI Bella Costa; como solución a los graves problemas a que seenfrenta la dirección de servicios técnicos de las instalaciones turísticas para realizar un mantenimiento con calidad y a unmenor costo.El desarrollo de un plan experimental, en las instalaciones del hotel, permitió obtener las curvas que expresan elcomportamiento de la degradación de estos sistemas en el tiempo, así como determinar el momento más oportuno para larealización del mantenimiento.La aplicación de esta investigación permitió la implementación de un mantenimiento menos costoso y de más calidad,aumentando la rentabilidad de la labor del mantenimiento, y lo que es decisivo en este tipo de instalación: la seguridad en laexplotación como garantía de un servicio sin fallas.Palabras claves: mantenimiento, refrigeración, predictivo, diagnóstico, pronóstico.____________________________________________________________________Abstract:In this paper is exposed the application of the maintenance by diagnosis and technical prediction to the centralized systemof air conditioned with heat recovery of the hotel Beautiful LTI Costa; as a solution to the serious problems that thetechnical management services faces in the tourist facilities to carry out a maintenance with quality and whith smaller cost.The development of an experimental plan, in the hotel facilities, allowed to obtain the curves that express the behavior ofthe degradation of these systems in the time, as well as to determine the most opportune moment for the realization of themaintenance.The application of this investigation allowed the implementation of a less expensive maintenance and of more quality,increasing the profitability of the maintenance work, and what is decisive in this installation type: the security in theexploitation as a

  2. Working fluid concentration measurement in solar air conditioning systems

    Energy Technology Data Exchange (ETDEWEB)

    Romero, R.J.; Basurto-Pensado, M.A. [Centro de Investigacion en Ingenieria y Ciencias Aplicadas, Universidad Autonoma del Estado de Morelos, Av. Universidad 1001. Col. Chamilpa, C.P. 62210, Cuernavaca, Morelos (Mexico); Jimenez-Heredia, A.H.; Sanchez-Mondragon, J.J. [Departamento de Optica, Instituto Nacional de Astrofisica Optica y Electronica, Luis Enrique Erro No. 1, Tonantzintla, Apartado Postal 51 y 216, C.P. 72000, Puebla (Mexico)

    2006-02-15

    In order to evaluate on-line corrosive electrolyte concentration in solar air conditioning systems, an optical technique to determine the concentration is being proposed. With this optical sensing method, it is possible to measure the percentage concentration of the aqueous corrosive lithium bromide solution at temperatures ranging from 25{sup o}C to 70{sup o}C and a maximum concentration of 60%. The measurement system is based on the refractive index of the solution and the data correlation, at several temperature and concentration values. The results of this work present a direct method for concentration measurement of corrosive liquids and also show the correlation among the three parameters: refractive index, temperature and weight concentration. This correlation can be used to develop the optical device for solar air conditioning systems to control and improve efficiency. (author)

  3. Parametric study of a solar air heater with and without thermal storage for solar drying applications

    Energy Technology Data Exchange (ETDEWEB)

    Aboul-Enein, S.; El-Sebaii, A.A.; Ramadan, M.R.I.; El-Gohary, H.G. [Tanta Univ., Physics Dept., Tanta (Egypt)

    2000-12-01

    A transient analytical model is presented for a flat-plate solar air heater with and without thermal storage. The flowing air temperature is assumed to vary with time and space coordinates. Analytical expressions are obtained for various temperatures of the air heater elements as well as for the temperature of the storage material. The performance of the air heater is investigated by computer simulation using the climatic conditions of Tanta (Lat. 30deg 47' N, Egypt). Effects of design parameters of the air heater such as length (L), width (b), gap spacing between the absorber plate and glass cover (d{sub f}), mass flow rate (m) and thickness and type of the storage material (sand, granite and water) on the outlet and average temperatures of the flowing air are studied. It is found that as L and b increase the average temperatures of flowing air (T{sub fav}) increases up to typical values for these parameters. Typical values for L and b are obtained as 3 and 2 m, respectively. The outlet temperature (T{sub fo}) of flowing air is found to decrease with increasing gap spacing and mass flow rate of air. Improvements in the heater performance with storage have been achieved at the optimum thickness (0.12 m) of the storage material. Therefore, the air heater can be used as a heat source for drying agricultural products and the drying process will continue during night, instead of re-absorption of moisture from the surrounding air. Comparisons between experimental and theoretical results indicated that the proposed mathematical model can be used for estimating the thermal performance of flat-plate solar air heaters with reasonable accuracy. (Author)

  4. STUDY AND NUMERICAL SIMULATION OF SOLAR SYSTEM FOR AIR HEATING

    Directory of Open Access Journals (Sweden)

    M. Ghodbane

    2016-01-01

    Full Text Available The use of solar energy in sunny countries, is an effective outil for compensate the lack in the energy, their benefits are not related only to its economic benefits but especially for the environmental protection, so we must find solutions to the problems of pollution. This work is a theoretical study of a solar flat plate collector ; air is used as the heat transfer fluid. In this study, we established in first step the calculation of solar radiation in various sites in Algeria (Adrar, El Oued, Bechar, Biskra and Tamanrasset. The second step is the parameters influence study of the sites and climate on the performance of our collector. The results obtained are encouraging for the use of this type in the heating in the winter, also it can be used in different kinds of drying.

  5. Optimization of solar air collector using genetic algorithm and artificial bee colony algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Sencan Sahin, Arzu [Sueleyman Demirel University, Technology Faculty, Isparta (Turkey)

    2012-11-15

    Thermal performance of solar air collector depends on many parameters as inlet air temperature, air velocity, collector slope and properties related to collector. In this study, the effect of the different parameters which affect the performance of the solar air collector are investigated. In order to maximize the thermal performance of a solar air collector genetic algorithm (GA) and artificial bee colony algorithm (ABC) have been used. The results obtained indicate that GA and ABC algorithms can be applied successfully for the optimization of the thermal performance of solar air collector. (orig.)

  6. Schottky Quantum Dot Solar Cells Stable in Air under Solar Illumination

    KAUST Repository

    Tang, Jiang

    2010-01-07

    (Figure Presented) The air stability and power conversion efficiency of solution-processed PbS quantum dot solar cells is dramatically improved by the insertion of 0.8 nm LiF between the PbS nanoparticle film and the Al contact. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA.

  7. Basement Kind Effects on Air Temperature of a Solar Chimney in Baghdad - Iraq Weather

    OpenAIRE

    Miqdam Tariq Chaichan

    2011-01-01

    A solar updraft tower power plant (solar tower) is a solar thermal power plant that utilizes a combination of solar air collector and central updraft tube to generate an induced convective flow which drives pressure staged turbines to generate electricity. This paper presents practical results of a prototype of a solar chimney with thermal mass, where the glass surface is replaced by transparence plastic cover. The study focused on chimney's basements kind effect on collected air temperatur...

  8. Solar air heaters. Concepts - system engineering - projecting. 2. ed.; Solare Luftheizsysteme. Konzepte - Systemtechnik - Planung

    Energy Technology Data Exchange (ETDEWEB)

    Filleux, Charles [Basler und Hofmann, Zuerich (Switzerland). Fachbereich Energie; Guetermann, Andreas [AMENA AG, Winterthur (Switzerland)

    2009-07-01

    Solar air collector systems can save energy in the heating of residential or commercial buildings. The authors provide a practical and detailed introduction to the technology and practical applications of solar air collector systems. Successful projects are presented, including cost and yields. Components are discussed in detail, i.e. collectors, heat stores, blowers, air ducts and control systems. Glazed and unglazed collectors are presented, and commercial collectors are compared with DIY collectors. Recommendations are given on the correct selection of the collector field size, flow cross sections, and storage capacity. The combination of components into a system and the dimensioning of systems are gone into, and an ecological assessment is presented. Exemplary projects are presented as well.

  9. Automotive absorption air conditioner utilizing solar and motor waste heat

    Science.gov (United States)

    Popinski, Z. (Inventor)

    1981-01-01

    In combination with the ground vehicles powered by a waste heat generating electric motor, a cooling system including a generator for driving off refrigerant vapor from a strong refrigerant absorbant solution is described. A solar collector, an air-cooled condenser connected with the generator for converting the refrigerant vapor to its liquid state, an air cooled evaporator connected with the condenser for returning the liquid refrigerant to its vapor state, and an absorber is connected to the generator and to the evaporator for dissolving the refrigerant vapor in the weak refrigerant absorbant solution, for providing a strong refrigerant solution. A pump is used to establish a pressurized flow of strong refrigerant absorbant solution from the absorber through the electric motor, and to the collector.

  10. Theoretical study for solar air pretreatment collector/regenerator

    Energy Technology Data Exchange (ETDEWEB)

    Peng Donggen; Zhang Xiaosong; Yin Yonggao [School of Energy and Environment, Southeast Univ., Nanjing (China)

    2008-07-01

    A new liquid regeneration equipment - solar air pretreatment collector/regenerator for liquid desiccant cooling system is put forward in this paper, which is preferable to solution regeneration in hot and moist climate in South China. The equipment can achieve liquid regeneration in lower temperature. When the solution and the air are in ''match'' state in collector/ regenerator, a match air to salt mass ratio ASMR* is found by theoretical study in which there is the largest theoretical storage capacity SC{sub max}. After two new concepts of the effective solution proportion (EPS) and the effective storage capacity (ESC) are defined, it is found by theoretical calculation that when ESP drops from 100% to 67%, ESC raises lowly, not drops and liquid outlet concentration C{sub str} {sub sol} increases from 40% to 49% in which its increment totals to 90%. All these data explain fully that air pretreatment liquid regeneration equipment enables to improve the performance of liquid desiccant cooling system. (orig.)

  11. Analysis of exergy and parametric study of a v-corrugated solar air heater

    Energy Technology Data Exchange (ETDEWEB)

    Hedayatizadeh, Mahdi [University of Tabriz, Department of Agricultural Machinery Engineering, Faculty of Agriculture, Tabriz (Iran, Islamic Republic of); University of Birjand, Faculty of Agriculture, P.O. Box 97175/331, Birjand (Iran, Islamic Republic of); Ajabshirchi, Yahya [University of Tabriz, Department of Agricultural Machinery Engineering, Faculty of Agriculture, Tabriz (Iran, Islamic Republic of); Sarhaddi, Faramarz; Farahat, Said [University of Sistan and Baluchestan, Department of Mechanical Engineering, Faculty of Engineering, P.O. Box 98164/161, Zahedan (Iran, Islamic Republic of); Safavinejad, Ali [University of Birjand, Department of Mechanical Engineering, Faculty of Engineering, Birjand (Iran, Islamic Republic of); Chaji, Hossein [University of Tabriz, Department of Agricultural Machinery Engineering, Faculty of Agriculture, Tabriz (Iran, Islamic Republic of); Center of Agriculture and Natural Resources of Khorasan Razavi Province, Ministry of Agriculture, Mashhad (Iran, Islamic Republic of)

    2012-07-15

    Solar air heater requires investigation for enhancement of solar energy conversion into heat. Different configurations with various artificial roughness geometries are proposed to date. In present study attention is paid on ways leading to more delivery of exergy by a v-corrugated solar air heater through parametric study. Effects of aspect ratio of the collector, inlet air temperature, mass flow rate per collector area etc. are studied. (orig.)

  12. Thermal performance optimization of a flat plate solar air heater using genetic algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Varun; Siddhartha [Department of Mechanical Engineering, National Institute of Technology, Hamirpur 177 005 (H.P.) (India)

    2010-05-15

    Thermal performance of solar air heater is low and different techniques are adopted to increase the performance of solar air heaters, such as: fins, artificial roughness etc. In this paper an attempt has been done to optimize the thermal performance of flat plate solar air heater by considering the different system and operating parameters to obtain maximum thermal performance. Thermal performance is obtained for different Reynolds number, emissivity of the plate, tilt angle and number of glass plates by using genetic algorithm. (author)

  13. Experimental investigations of the performance of a solar air collector with latent heat thermal storage integrated with the solar absorber

    OpenAIRE

    Hejcik J.; Pech O.; Charvat P.

    2013-01-01

    The paper deals with experimental investigations of the performance of a solar air collector with latent heat thermal storage integrated with the solarabsorber. The main purpose of heat storage in solar thermal systems is to store heat when the supply of solar heat exceeds demand and release it when otherwise. A number of heat storage materials can be used for this purpose; the phase change materials among them. Short-term latent heat thermal storage integrated with the solar absorber can sta...

  14. Thermal performance of an open thermosyphon using nanofluid for evacuated tubular high temperature air solar collector

    International Nuclear Information System (INIS)

    Highlights: • A novel solar air collector with simplified CPC and open thermosyphon is designed and tested. • Simplified CPC has a much lower cost at the expense of slight efficiency loss. • Nanofluid effectively improves thermal performance of the above solar air collector. • Solar air collector with open thermosyphon is better than that with concentric tube. - Abstract: A novel evacuated tubular solar air collector integrated with simplified CPC (compound parabolic concentrator) and special open thermosyphon using water based CuO nanofluid as the working fluid is designed to provide air with high and moderate temperature. The experimental system has two linked panels and each panel includes an evacuated tube, a simplified CPC and an open thermosyphon. Outdoor experimental study has been carried out to investigate the actual solar collecting performance of the designed system. Experimental results show that air outlet temperature and system collecting efficiency of the solar air collector using nanofluid as the open thermosyphon’s working fluid are both higher than that using water. Its maximum air outlet temperature exceeds 170 °C at the air volume rate of 7.6 m3/h in winter, even though the experimental system consists of only two collecting panels. The solar collecting performance of the solar collector integrated with open thermosyphon is also compared with that integrated with common concentric tube. Experimental results show that the solar collector integrated with open thermosyphon has a much better collecting performance

  15. Reduced heat stress in offices in the tropics using solar powered drying of the supply air

    DEFF Research Database (Denmark)

    Gunnarsen, Lars; Santos, A M B

    2002-01-01

    Many solutions to indoor climate problems known from developed countries may have prohibitive installation and running costs in developing countries. The purpose was to develop a low-cost solution to heat stress in a hot and humid environment based on solar powered drying of supply air. Dry supply...... air may facilitate personal cooling by increased evaporation of sweat. Heat acclimatized people with efficient sweating may in particular benefit from this cooling. A prototype solar powered supply system for dried-only air was made. Air from the system was mixed with room air, heated to six different...... content of room air, temperature of supply air and moisture content of supply air was developed based on the experiments. Reduction of moisture content in the supply air by 1.6 g/kg had the same effect as lowering the operative temperature by 1 degree C. The solar-powered system for supplying dry air...

  16. Air and liquid solar heating system with heatpump, VP-SOL

    DEFF Research Database (Denmark)

    Kristiansen, Finn Harken; Jensen, Søren Østergaard

    1998-01-01

    .The sensor of the differential control of the fluid pump is placed inappropriately. Hereby the fluid part performs about 5% less.The air through the solar collectors is controlled by the difference between the room temperature and the solar collector temperature. The air differential control should...... be changed in such a way that the air is drawn through the solar collectors when the air temperature of the solar collectors is e.g. 5 K higher than the open air temperature.It has turned out that under the given conditions the system (compared to the simulations) performs as expected.If the heat pump......For more than a year, measurements have been made on an air/fluid solar heating system with heat pump. The annual thermal performance of the system has been found and compared with simulations carried out by means of the simulation program KVIKSOL.The heat loss of the hot water tank is calculated...

  17. Parametric simulation and experimental analysis of earth air heat exchanger with solar air heating duct

    Directory of Open Access Journals (Sweden)

    Sanjeev Jakhar

    2016-06-01

    Full Text Available Earth air heat exchanger (EAHE systems are insufficient to meet the thermal comfort requirements in winter conditions. The low heating potential of such systems can be improved by integrating the system with solar air heating duct (SAHD. The aim of this paper is to present a model to estimate the heating potential for EAHE system with and without SAHD. The model is generated using TRNSYS 17 simulation tool and validated against experimental investigation on an experimental set-up in Ajmer, India. The experiment was done during the winter season, where the system was evaluated for different inlet flow velocities, length and depth of buried pipe. From the experimentation, it was observed that the depth of 3.7 m is sufficient for pipe burial and the 34 m length of pipe is sufficient to get optimum EAHE outlet temperature. It is also observed that increase in flow velocity results in drop in EAHE outlet temperature, while room temperature is found to increase for higher velocities (5 m/s. The COP of the system also increased up to 6.304 when assisted with solar air heating duct. The results obtained from the experiment data are in good agreement with simulated results within the variation of up to 7.9%.

  18. Development of a solar powered residential air conditioner (General optimization)

    Science.gov (United States)

    Lowen, D. J.

    1976-01-01

    A commercially available 3-ton residential Lithium Bromide (LiBr) absorption air conditioner was modified for use with lower temperature solar heated water. The modification included removal of components such as the generator, concentration control chamber, liquid trap, and separator; and the addition of a Chrysler designed generator, an off-the-shelf LiBr-solution pump. The design goal of the modified unit was to operate with water as the heat-transfer fluid at a target temperature of 85 C (185 F), 29.4 C (85 F) cooling water inlet, producing 10.5 kW (3 tons) of cooling. Tests were performed on the system before and after modification to provide comparative data. At elevated temperatures (96 C, 205 F), the test results show that Lithium Bromide was carried into the condenser due to the extremely violent boiling and degraded the evaporator performance.

  19. Development and testing of a solar air heater for a teaching laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Yousif, K.M.; Smith, B.E. [Brunel Univ., Uxbridge (United Kingdom)

    1996-09-01

    This paper describes the development and testing of an educational solar air heater. The flat-plate solar air heater has been used as a teaching rig for undergraduate students in measurements laboratory sessions, during which the collector efficiency is determined. The results of indoor testing of the solar collector are presented, together with some details of the test facility. It is hoped that use of the solar air heater will contribute to the students` understanding of subjects such as energy conversion and utilization and heat transfer, together with instrumentation. (Author)

  20. A review on methodology of artificial roughness used in duct of solar air heaters

    Energy Technology Data Exchange (ETDEWEB)

    Bhushan, Brij; Singh, Ranjit [Department of Mechanical Engineering, Beant College of Engineering and Technology, Gurdaspur 143521, Punjab (India)

    2010-01-15

    In order to enhance rate of heat transfer to flowing air in the duct of a solar air heater, artificially roughened surface of absorber plate is considered to be an effective technique. Investigators reported various roughness geometries in literature for studying heat transfer and friction characteristics of an artificially roughened duct of solar air heaters. In the present paper an attempt has been made to categorize and review the reported roughness geometries used for creating artificial roughness. Heat transfer coefficient and friction factor correlations developed by various investigators for roughened ducts of solar air heaters have also been reported in the present paper. (author)

  1. Influence of climate and air pollution on solar energy development in Serbia

    OpenAIRE

    Radivojević Aleksandar R.; Pavlović Tomislav M.; Milosavljević Dragana D.; Đorđević Amelija V.; Pavlović Mila A.; Filipović Ivan M.; Pantić Lana S.; Punišić Milan R.

    2015-01-01

    The paper introduces basic information on the geographical location, climate and solar radiation in Serbia. It focuses particularly on the air pollution in Serbia and its influence on the solar cells energy efficiency. Moreover, detailed information on the development of solar energy in Serbia and the examples of the application of the low, medium and high temperature and photovoltaic conversion of solar radiation is provided. The paper also gives an overvi...

  2. Energy and exergy analysis in double-pass solar air heater

    Indian Academy of Sciences (India)

    P VELMURUGAN; R KALAIVANAN

    2016-03-01

    In this study, an attempt is made to improve the energy and exergy performance of solar air heater by employing double pass with different absorber surface geometries (roughened, finned, and v-corrugated wire mesh) in the second pass, and also by mounting longitudinal fins in the back side of the absorber plate (first pass). The effect of varied mass flow rate and solar intensity on temperature rise of air, energy efficiency, exergy gain and pressure drop at steady state condition was determined for different types of solar air heaters utilizing an indoor solar simulator. The temperature rise of air, thermal efficiency and exergy gain depends on mass flow rate, surface geometries of absorber and solar intensity, whereas the pressure drop depends on mass flow rate andsurface geometries of absorber.

  3. Experimental study on flat plate air solar collector using a thin sand layer

    Science.gov (United States)

    Lati, Moukhtar; Boughali, Slimane; Bouguettaia, Hamza; Mennouche, Djamel; Bechki, Djamel

    2016-07-01

    A flat plate air solar collector was constructed in the laboratory of New and Renewable Energy in Arid Zones LENREZA, Ouargla University-South East Algeria. The absorber of the flat plate air solar collector was laminated with a thin layer of local sand. This acted as a thermal storage system (packed bed) with a collecting area of 2.15 m2 (0.86 m × 2.5 m). It was noticed that the solar heater integrated with the thermal storage material delivered comparatively higher temperatures; thus, giving a better efficiency than the air heater without the thermal storage system.

  4. Investigation on regeneration and energy storage characteristics of a solar liquid desiccant air-conditioning system

    Institute of Scientific and Technical Information of China (English)

    SHI Mingheng; DU Bin; ZHAO Yun

    2007-01-01

    Solar liquid desiccant air-conditioner is a new air-conditioning system in which liquid desiccant can be regenerated by solar energy and energy can be stored in the form of chemical energy in the liquid desiccant.In this paper regeneration and energy storage characteristics were studied theoretically and experimentally.Two criterion equations for heat and mass transfer in the regeneration process were obtained.The main factors that influence the regeneration process were analyzed.A principal solar liquid desiccant air-conditioning system under energy storage operating mode is proposed.

  5. Performance Analysis of a Solar Dryer Equipped with a Recycling Air System and Desiccant Chamber

    Directory of Open Access Journals (Sweden)

    M.H Aghkhani

    2013-09-01

    Full Text Available Drying is a high energy consuming process. Solar drying is one of the most popular methods for dehydration of agricultural products. In the present study, the performance of a forced convection solar dryer equipped with recycling air system and desiccant chamber was investigated. The solar dryer is comprised of solar collector, drying chamber, silica jell desiccant chamber, air ducts, fan and measuring and controlling system. Drying rate and energy consumption in three levels of air temperature (40, 45 and 50 oC and two modes of drying (with recycling air and no-recycling with open duct system were measured and compared. The results showed that increasing the drying air temperature decreased the drying time and increased the energy consumption in the mode of non-recycling air system. The dryer efficiency and drying rate were better in the mode of recycling air system than open duct system. The highest dryer efficiency was obtained from drying air temperature of 50 oC and the mode of recycling air system. In general, the efficiency of solar collector and the highest efficiency of the dryer were 0.34 and 0.41, respectively.

  6. Discussion of mechanical design for pressured cavity-air-receiver in solar power tower system

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Zhilin; Zhang, Yaoming; Liu, Deyou; Wang, Jun; Liu, Wei [Hohai Univ., Nanjing (China). New Materials and Energy Sources Research and Exploitation Inst.

    2008-07-01

    In 2005, Hohai university and Nanjing Chunhui science and technology Ltd. of China, cooperating with Weizmann Institute of Science and EDIG Ltd. of Israel, built up a 70kWe solar power tower test plant in Nanjing, Jiangsu province, China, which was regarded as the first demonstration project to demonstrate the feasibility of solar power tower system in China. The system consists of heliostats field providing concentrated sunlight, a solar tower with a height of 33 meter, a pressured cavity-air-receiver transforming solar energy to thermal energy, a modified gas turbine adapting to solar power system, natural gas subsystem for solar-hybrid generation, cooling water subsystem for receiver and CPC, controlling subsystem for whole plant, et al. In this system, air acts as actuating medium and the system works in Brayton cycle. Testing results show that solar power tower system is feasible in China. To promote the development of solar powered gas turbine system and the pressured cavity-air-receiver technology in China, it is necessary to study the mechanical design for pressured Cavity-air-receiver. Mechanical design of pressured cavity-air-receiver is underway and some tentative principles for pressured cavity-air-receiver design, involving in power matching, thermal efficiency, material choosing, and equipment security and machining ability, are presented. At the same time, simplified method and process adapted to engineering application for the mechanical design of pressured cavity-air-receiver are discussed too. Furthermore, some design parameters and appearance of a test sample of pressured cavity-air-receiver designed in this way is shown. It is appealed that, in China, the research in this field should be intensified and independent knowledge patents for pivotal technological equipments such as receiver in solar power tower system should be formed. (orig.)

  7. Performance advancement of solar air-conditioning through integrated system design for building

    International Nuclear Information System (INIS)

    This study is to advance the energy performance of solar air-conditioning system through appropriate component integration from the absorption refrigeration cycle and proper high-temperature cooling. In the previous studies, the solar absorption air-conditioning using the working pair of water – lithium bromide (H2O–LiBr) is found to have prominent primary energy saving than the conventional compression air-conditioning for buildings in the hot-humid climate. In this study, three integration strategies have been generated for solar cooling, namely integrated absorption air-conditioning; integrated absorption-desiccant air-conditioning; and integrated absorption-desiccant air-conditioning for radiant cooling. To realize these ideas, the working pair of ammonia – water (NH3–H2O) was used in the absorption cycle, rather than H2O–LiBr. As such, the evaporator and the condenser can be separate from the absorption refrigeration cycle for the new configuration of various integrated design alternatives. Through dynamic simulation, the year-round primary energy saving of the proposed integration strategies for solar NH3–H2O absorption air-conditioning systems could be up to 50.6% and 25.5%, as compared to the conventional compression air-conditioning and the basic solar H2O–LiBr absorption air-conditioning respectively. Consequently, carbon reduction of building air-conditioning can be achieved more effectively through the integrated system design in the hot and humid cities. - Highlights: • Three integration strategies, IAAU, IADAU and IADAU-RC, are proposed to advance solar air-conditioning. • NH3–H2O is adopted for absorption refrigeration instead of H2O–LiBr. • Separate evaporator and condenser, desiccant cooling and radiant cooling are designed for IADAU-RC. • IADAU-RC can have 50.6% primary energy saving against the conventional air-conditioning

  8. Arkansas Solar Retrofit Guide. Greenhouses, Air Heaters and Water Heaters.

    Science.gov (United States)

    Skiles, Albert; Rose, Mary Jo

    Solar retrofits are devices of structures designed to be attached to existing buildings to augment their existing heating sources with solar energy. An investigation of how solar retrofits should be designed to suit the climate and resources of Arkansas is the subject of this report. Following an introduction (section 1), section 2 focuses on…

  9. Optimum selection of solar collectors for a solar-driven ejector air conditioning system by experimental and simulation study

    International Nuclear Information System (INIS)

    Highlights: ► Three solar collectors have been compared to drive ejector air conditioning system. ► A simulation program was constructed to study the effect parameters. ► The outdoor test were conducted to validate the solar collector modeling. ► Simulation program was found to predict solar collector performance accurately. ► The optimal design of solar collector system was carried out. - Abstract: In this paper, three different solar collectors are selected to drive the solar ejector air conditioning system for Mediterranean climate. The performance of the three selected solar collector are evaluated by computer simulation and lab test. Computer model is incorporated with a set of heat balance equations being able to analyze heat transfer process occurring in separate regions of the collector. It is found simulation and test has a good agreement. By the analysis of the computer simulation and test result, the solar ejector cooling system using the evacuated tube collector with selective surface and high performance heat pipe can be most economical when operated at the optimum generating temperature of the ejector cooling machine.

  10. Hybrid system: Heat pump-solar air dryer for grains; Sistema hibrido: bomba de calor - calentador solar de aire para el secado de productos agricolas

    Energy Technology Data Exchange (ETDEWEB)

    Soto Gomez, Willfredo [Instituto Tecnologico de Tijuana, Tijuana (Mexico); Ortega Herrera, Jose Angel [Instituto Politecnico Nacional, Mexico, D.F. (Mexico)

    2000-07-01

    Design, building, operation and evaluation energy wise of a hybrid experimental type, with heat pump, that uses no chloride, does not destroy the ozone layer. It is solar air dryer for grains. In this research we dry rice. It has tree systems: 1.- A mechanical compression heat pump, 2.- An air solar heater, and 3.- An agriculture products dryer. The drying capacity is 20 pounds of grain /day, with a median daily solar radiation. The costs is approximately U.S. $ 6 000.00. The heat pump used 22 refrigerant first, and now works with refrigerant SUVA 9000. This refrigerant will be available this year in the I.S., it is one of the ecological class that substitutes the chlorofluorocarbonates. [Spanish] Se disena, construye, opera, y evalua energeticamente, un sistema hibrido tipo experimental, con bomba de calor que utiliza refrigerante que no contiene cloro, y no destruye la capa de ozono y un calentador solar de aire, para secar granos. En este trabajo secamos arroz. Se compone de tres sistemas: 1.- Bomba de calor por compresion mecanica, 2.- Calentador solar de aire, 3.- Secador de productos agricolas. La capacidad de secado es de 10 Kilos de granos/dia promedio. Tiene un costo aproximado de $ 60 000. La bomba de calor utiliza refrigerante 22 en una primera generacion, y actualmente opera con un refrigerante SUVA 9000, en una segunda generacion, este refrigerante se comercializara en este ano, en la Union Americana, pertenece a la familia de los llamados refrigerantes ecologicos, sustitutos de los clorofluorocarbonados.

  11. Experimental evaluation of a direct air-cooled lithium bromide-water absorption prototype for solar air conditioning

    OpenAIRE

    González-Gil, A.; Izquierdo, M.; Marcos, J.D.; Palacios, E.

    2011-01-01

    Abstract A new direct air-cooled single-effect LiBr-H2O absorption prototype is described and proposed for use in solar cooling. As distinguishing aspects, it presents: an adiabatic absorber using flat-fan sheets; an air-cooling system that directly refrigerates both the condenser and the absorber and; the possibility of being operated also as a double-effect unit. A solar facility comprising a 48m2 field of flat-plate collectors was used to test the single-effect operation mode of...

  12. A review of the mathematical models for predicting solar air heaters systems

    Energy Technology Data Exchange (ETDEWEB)

    Tchinda, Rene [IUT FOTSO VICTOR, University of Dschang, PO Box 134 Bandjoun (Cameroon); ICTP Strada Costiera 11, 34014 Trieste (Italy)

    2009-10-15

    A mathematical model of the closed solar air heaters is used in particular, to assist in interpreting the observed phenomena in the solar air heaters, to design the system, to predict the trends, and to assist in optimization. In this paper, various mathematical models, mainly analyzing the heat transfer process of solar air heaters, are reviewed and classified based on the model, the number of the cover, the shape of the absorber and the presence or not of the packing bed. Although the models have evolved to a point where several features of the process can be predicted, more effort is required before the models can be applied to define actual operating conditions as well as to further investigate new closed solar air heaters. It is shown that the major governing equations in the models are based on the first law of thermodynamics. (author)

  13. Effective Efficiency of Solar Air Heaters of Different Types of Roughness Geometries over Absorber Plate

    Directory of Open Access Journals (Sweden)

    Maneesh KAUSHAL

    2014-09-01

    Full Text Available Artificial roughness has been found to enhance the rate of heat transfer in solar air heater ducts. However, improvement in heat transfer enhancement is invariably accompanied by increased pumping power. Several investigators have investigated the effect of different types of roughness on solar air heaters on the basis of heat transfer and friction factor. This paper presents a comparison of effective efficiency of solar air heaters of various types of roughness geometries over the absorber plate. These geometries have been used by various investigators in order to increase the heat transfer and friction factor in solar air heaters. Based upon correlations developed by various investigators, effective efficiency is also compared for a set of roughness geometries within the investigated range of operating parameters.doi:10.14456/WJST.2014.92

  14. Characterization of Air-Based Photovoltaic Thermal Panels with Bifacial Solar Cells

    OpenAIRE

    Ooshaksaraei, P.; K. Sopian; Zulkifli, R.; Saleem H. Zaidi

    2013-01-01

    Photovoltaic (PV) panels account for a majority of the cost of photovoltaic thermal (PVT) panels. Bifacial silicon solar panels are attractive for PVT panels because of their potential to enhance electrical power generation from the same silicon wafer compared with conventional monofacial solar panels. This paper examines the performance of air-based bifacial PVT panels with regard to the first and second laws of thermodynamics. Four air-based bifacial PVT panels were designed. The maximum ef...

  15. Sustainable Production of Ammonia solely using Solar Power, Water, and Air

    OpenAIRE

    Call, Friedemann; Felinks, Jan; Lange, Matthias; Sattler, Christian

    2015-01-01

    A process is proposed capable to produce ammonia solely from sun, water and air and therewith promising to replace the million-ton consumption of natural gas with solar production of hydrogen and nitrogen. While several routes for solar hydrogen production were important research subjects for decades, an innovative and sustainable nitrogen generation is still missing. Our approach to produce nitrogen is based on a novel air separation: a thermochemical cycle based on ...

  16. The solar power tower Jülich – a solar thermal power plant for test and demonstration of air receiver

    OpenAIRE

    Hennecke, Klaus; Schwarzbözl, Peter; Hoffschmidt, Bernhard; Göttsche, Joachim; Koll, Gerrit; Beuter, Matthias; Hartz, Thomas

    2007-01-01

    The paper explains the fundamentals of the open volumetric receiver technology and shows the history of its development. It gives technical information about the system definition and the engineering of the Solar Power Tower Jülich. The open volumetric receiver technology allows the use of air as heat transfer medium at high temperatures in solar thermal power tower plants. It combines porous ceramic or metallic absorber structures with a strictly modular receiver design. Highly concentrat...

  17. Design guides for solar assisted air conditioning; Auslegungshinweise fuer die Solargestuetzte Klimatisierung

    Energy Technology Data Exchange (ETDEWEB)

    Franzke, U.; Seifert, C. [Institut fuer Luft- und Kaeltetechnik gGmbH, Dresden (Germany)

    2005-10-01

    The design of solar assisted air conditioning systems required a detailed consideration of the whole system, which consist of the building, the use, the air handling unit and the solar energy production. The decision about the application of solar energy is necessary in an earlier phase of the design process of the building. But at this moment, the necessary information are not available. With help of the simulation tool SOLAC it's possible to define an optimised system on a low level of information input. (orig.)

  18. Influence of climate and air pollution on solar energy development in Serbia

    Directory of Open Access Journals (Sweden)

    Radivojević Aleksandar R.

    2015-01-01

    Full Text Available The paper introduces basic information on the geographical location, climate and solar radiation in Serbia. It focuses particularly on the air pollution in Serbia and its influence on the solar cells energy efficiency. Moreover, detailed information on the development of solar energy in Serbia and the examples of the application of the low, medium and high temperature and photovoltaic conversion of solar radiation is provided. The paper also gives an overview of the installed greater capacity solar power stations related to the electricity network and the smaller capacity solar power stations as the independent sources of electricity in Serbia. In conclusion, the paper stresses Serbia’s favourite climate and other conditions for the prospective successful development of solar energy.

  19. A numerical study of a vertical solar air collector with obstacle

    Science.gov (United States)

    Moumeni, A.; Bouchekima, B.; Lati, M.

    2016-07-01

    Because of the lack of heat exchange obtained by a solar air between the fluid and the absorber, the introduction of obstacles arranged in rows overlapping in the ducts of these systems improves heat transfer. In this work, a numerical study using the finite volume methods is made to model the dynamic and thermal behavior of air flow in a vertical solar collector with baffles destined for integration in building. We search essentially to compare between three air collectors models with different inclined obstacles angle. The first kind with 90° shows a good performance energetic and turbulent.

  20. SolAir. Innovative solar collectors for efficient and cost-effective solar thermal power generation - Final report

    Energy Technology Data Exchange (ETDEWEB)

    Barbato, M. C.; Haueter, Ph.; Bader, R.; Steinfeld, A.; Pedretti, A.

    2008-12-15

    This report presents the main results of the project. The project has been started at the end of 2007 and has been successfully finished in December 2008. The present project of ALE AirLight Energy aims at the engineering investigation and design of a novel concept of a solar collector system for efficient and cost-effective solar thermal power generation. The technology exploits an air-inflated reflective structure to concentrate solar radiation. This new arrangement reduces investment costs of the collector field and promises to be economically competitive. A first prototype, built in 2007, has been redesigned and heavily modified during this project. In the new configuration, by using secondary mirrors, the focal area is located close to the main structure and allows the integration of the receiver into the inflated structure. The topics developed in this document are as follows: (i) Design solutions for the concentrated energy receiver suitable for the revised SolAir concentrator concept. (ii) Solar flux simulation via Monte Carlo method. (iii) New version of the ALE AirLight Energy concentrator prototype. (iv) Prototype radiative flux measurements. (author)

  1. Assessment of Performance Characteristic of Solar Air Heater with Assorted Geometries - A Review

    Directory of Open Access Journals (Sweden)

    Alok Kumar Rohit

    2016-01-01

    Full Text Available Artificial roughness is an efficient way for increasing the heat transfer rate in solar air heater with the corresponding improvement in its thermal performance. A viscous sub-layer is responsible for the low heat transfer coefficient between absorber plate and flowing air. Repeated ribs in form of artificial roughness are an effective way to increase the heat transfer rate and improving the performance of solar air heater. Artificial roughness of the absorber plate is much economical and effective way to improve the thermal performance of solar air heater. Several investigators have done various investigations to improve heat transfer coefficient with little penalty of friction factor. They have also developed different correlation for heat transfer coefficient and friction factor. The correlations developed for heat transfer and friction factor by various investigators have been reviewed and presented.

  2. Effective efficiency prediction for discrete type of ribs used in solar air heaters

    Directory of Open Access Journals (Sweden)

    Muneesh Sethi, Mridul Sharma, Varun

    2010-03-01

    Full Text Available The use of an artificial roughness on a surface is an effective technique to enhance the heat transfer from the collector plate to the air in a solar air heater duct. However, artificial roughness leads to even more fluid pressure thereby increasing the pumping power. Number of geometries of roughness elements has been investigated on the heat transfer and friction characteristics of solar air heater ducts. This paper presents a comparison of effective efficiency of solar air heaters having different types of geometry of roughness elements (discrete ribs on the absorber plate. The effective efficiency has been computed by using the correlations for heat transfer and friction factor developed by various investigators within the investigated range of operating and system parameters.

  3. Effective efficiency prediction for discrete type of ribs used in solar air heaters

    Energy Technology Data Exchange (ETDEWEB)

    Sethi, Muneesh [Mechanical Engineering Department, IEET Baddi - 173205 (India); Sharma, Mridul; Varun [Department of Mechanical Engineering, National Institute of Technology Hamirpur - 177005 (India)

    2010-07-01

    The use of an artificial roughness on a surface is an effective technique to enhance the heat transfer from the collector plate to the air in a solar air heater duct. However, artificial roughness leads to even more fluid pressure thereby increasing the pumping power. Number of geometries of roughness elements has been investigated on the heat transfer and friction characteristics of solar air heater ducts. This paper presents a comparison of effective efficiency of solar air heaters having different types of geometry of roughness elements (discrete ribs) on the absorber plate. The effective efficiency has been computed by using the correlations for heat transfer and friction factor developed by various investigators within the investigated range of operating and system parameters.

  4. Analytical and Experimental Study of Recycling Baffled Double-Pass Solar Air Heaters with Attached Fins

    Directory of Open Access Journals (Sweden)

    Chun Sheng Lin

    2013-03-01

    Full Text Available The study of the heat transfer of solar air heaters with a new design using an absorbing plate with fins and baffles, which facilitate the recycling of flowing air, is reported. The mathematical formulation and analytical analysis for such a recyclic baffled double-pass solar air heater were developed theoretically. The performance of the device was studied experimentally as well. The theoretical predicted and experimental results were compared with another design, i.e., a downward-type single-pass solar air heater without recycle and double-pass operations reported in our previous work. Significant improvement in heat-transfer efficiency is achieved with the baffle and fin design due to the recycling heating and the extended heat transfer area. The effects of mass flow rate and recycle ratio on the heat-transfer efficiency enhancement as well as on the power consumption increment are also discussed.

  5. Analytical and Experimental Study of Recycling Baffled Double-Pass Solar Air Heaters with Attached Fins

    Energy Technology Data Exchange (ETDEWEB)

    Chii Dong Ho; Hsuan Chang; Chun Sheng Lin; Rei Chi Wang [Energy and Opto-Electronic Materials Research Center, Department of Chemical and Materials Engineering, Tamkang University, Tamsui, New Taipei City, Taiwan (China)

    2013-04-15

    The study of the heat transfer of solar air heaters with a new design using an absorbing plate with fins and baffles, which facilitate the recycling of flowing air, is reported. The mathematical formulation and analytical analysis for such a recyclic baffled double-pass solar air heater were developed theoretically. The performance of the device was studied experimentally as well. The theoretical predicted and experimental results were compared with another design, i.e., a downward-type single-pass solar air heater without recycle and double-pass operations reported in our previous work. Significant improvement in heat-transfer efficiency is achieved with the baffle and fin design due to the recycling heating and the extended heat transfer area. The effects of mass flow rate and recycle ratio on the heat-transfer efficiency enhancement as well as on the power consumption increment are also discussed.

  6. Air stable organic-inorganic nanoparticles hybrid solar cells

    Science.gov (United States)

    Qian, Lei; Yang, Jihua; Xue, Jiangeng; Holloway, Paul H.

    2015-09-29

    A solar cell includes a low work function cathode, an active layer of an organic-inorganic nanoparticle composite, a ZnO nanoparticle layer situated between and physically contacting the cathode and active layers; and a transparent high work function anode that is a bilayer electrode. The inclusion of the ZnO nanoparticle layer results in a solar cell displaying a conversion efficiency increase and reduces the device degradation rate. Embodiments of the invention are directed to novel ZnO nanoparticles that are advantageous for use as the ZnO nanoparticle layers of the novel solar cells and a method to prepare the ZnO nanoparticles.

  7. Empirical analysis of the solar contribution to global mean air surface temperature change

    CERN Document Server

    Scafetta, Nicola

    2009-01-01

    The solar contribution to global mean air surface temperature change is analyzed by using an empirical bi-scale climate model characterized by both fast and slow characteristic time responses to solar forcing: $\\tau_1 =0.4 \\pm 0.1$ yr, and $\\tau_2= 8 \\pm 2$ yr or $\\tau_2=12 \\pm 3$ yr. Since 1980 the solar contribution to climate change is uncertain because of the severe uncertainty of the total solar irradiance satellite composites. The sun may have caused from a slight cooling, if PMOD TSI composite is used, to a significant warming (up to 65% of the total observed warming) if ACRIM, or other TSI composites are used. The model is calibrated only on the empirical 11-year solar cycle signature on the instrumental global surface temperature since 1980. The model reconstructs the major temperature patterns covering 400 years of solar induced temperature changes, as shown in recent paleoclimate global temperature records.

  8. Basement Kind Effects on Air Temperature of a Solar Chimney in Baghdad - Iraq Weather

    Directory of Open Access Journals (Sweden)

    Miqdam Tariq Chaichan

    2011-01-01

    Full Text Available A solar updraft tower power plant (solar tower is a solar thermal power plant that utilizes a combination of solar air collector and central updraft tube to generate an induced convective flow which drives pressure staged turbines to generate electricity. This paper presents practical results of a prototype of a solar chimney with thermal mass, where the glass surface is replaced by transparence plastic cover. The study focused on chimney's basements kind effect on collected air temperatures. Three basements were used: concrete, black concrete and black pebbles basements. The study was conducted in Baghdad from August to November 2009. The results show that the best chimney efficiency attained was 49.7% for pebbles base. The highest collected air temperature reached was 49ºC when using the black pebbles basement also.also, the maximum basement temperature measured was 59ºC for black pebbles. High increaments in collected air temperatures were achieved in comparison with the ambient air temperatures for the three basement kinds. The highest temperature difference reached was 22ºC with the pebble ground.

  9. Experimental and simulation studies on a single pass, double duct solar air heater

    Energy Technology Data Exchange (ETDEWEB)

    Forson, F.K. [Kwame Nkrumah Univ. of Science and Technology, Dept. of Mechanical Engineering, Kumasi (Ghana); Rajakaruna, H. [De Montfort Univ., School of Engineering and Technology, Leicester (United Kingdom)

    2003-05-01

    A mathematical model of a single pass, double duct solar air heater (SPDDSAH) is described. The model provides a design tool capable of predicting: incident solar radiation, heat transfer coefficients, mean air flow rates, mean air temperature and relative humidity at the exit. Results from the simulation are presented and compared with experimental ones obtained on a full scale air heater and a small scale laboratory one. Reasonable agreement between the predicted and measured values is demonstrated. Predicted results from a parametric study are also presented. It is shown that significant improvement in the SPDDSAH performance can be obtained with an appropriate choice of the collector parameters and the top to bottom channel depth ratio of the two ducts. The air mass flow rate is shown to be the dominant factor in determining the overall efficiency of the heater. (Author)

  10. Air cooled absorption chillers for solar cooling applications

    Science.gov (United States)

    Biermann, W. J.; Reimann, R. C.

    1982-03-01

    The chemical composition of a 'best' absorption refrigerant system is identified, and those properties of the system necessary to design hot water operated, air cooled chilling equipment are determined. Air cooled chillers from single family residential sizes into the commercial rooftop size range are designed and operated.

  11. Solar Air Collectors for Space Heating and Ventilation Applications—Performance and Case Studies under Romanian Climatic Conditions

    Directory of Open Access Journals (Sweden)

    Sanda Budea

    2014-06-01

    Full Text Available Solar air collectors have various applications: on the one hand, they can be used for air heating in cold seasons; on the other hand they can be used in summer to evacuate the warm and polluted air from residential, offices, industrial, and commercial buildings. The paper presents experimental results of a solar collector air, under the climatic conditions of the Southeastern Europe. The relationships between the direct solar irradiation, the resulting heat flow, the air velocity at the outlet, the air flow rate, the nominal regime of the collector and the efficiency of conversion of solar energy into thermal energy are all highlighted. Thus, it was shown that after a maximum 50 min, solar air collectors, with baffles and double air passage can reach over 50% efficiency for solar irradiation of 900–1000 W/m2. The article also presents a mathematical model and the results of a computational program that allows sizing solar collectors for the transfer of air, with the purpose of improving the natural ventilation of buildings. The article is completed with case studies, sizing the area to be covered with solar collectors, to ensure ventilation of a house with two floors or for an office building. In addition, the ACH (air change per hour coefficient was calculated and compared.

  12. Modeling solar-driven ejector refrigeration system offering air conditioning for office buildings

    Energy Technology Data Exchange (ETDEWEB)

    Guo, J.; Shen, H.G. [School of Environmental Science and Engineering, Donghua University, 2999 North Renmin Road, Shanghai 201620 (China)

    2009-02-15

    A lumped method combined with dynamic model is proposed for use in investigating the performance and solar fraction of a solar-driven ejector refrigeration system (SERS) using R134a, for office air conditioning application for buildings in Shanghai, China. Classical hourly outdoor temperature and solar radiation model were used to provide basic data for accurate analysis of the system performance. Results indicate that during the office working-time, i.e., from 9:00 to 17:00, the average COP and the average solar fraction of the system were 0.48 and 0.82 respectively when the operating conditions were: generator temperature (85 C), evaporator temperature (8 C) and condenser temperature varying with ambient temperature. Compared with traditional compressor based air conditioner, the system can save upto 80% electric energy when providing the same cooling capacity for office buildings. Hence, the system offers a good energy conservation method for office buildings. (author)

  13. Numerical evaluation of an innovative cup layout for open volumetric solar air receivers

    Science.gov (United States)

    Cagnoli, Mattia; Savoldi, Laura; Zanino, Roberto; Zaversky, Fritz

    2016-05-01

    This paper proposes an innovative volumetric solar absorber design to be used in high-temperature air receivers of solar power tower plants. The innovative absorber, a so-called CPC-stacked-plate configuration, applies the well-known principle of a compound parabolic concentrator (CPC) for the first time in a volumetric solar receiver, heating air to high temperatures. The proposed absorber configuration is analyzed numerically, applying first the open-source ray-tracing software Tonatiuh in order to obtain the solar flux distribution on the absorber's surfaces. Next, a Computational Fluid Dynamic (CFD) analysis of a representative single channel of the innovative receiver is performed, using the commercial CFD software ANSYS Fluent. The solution of the conjugate heat transfer problem shows that the behavior of the new absorber concept is promising, however further optimization of the geometry will be necessary in order to exceed the performance of the classical absorber designs.

  14. Degradation mechanism of Cu(In,Ga)Se2 solar cells induced by exposure to air

    Science.gov (United States)

    Nishinaga, Jiro; Kamikawa, Yukiko; Koida, Takashi; Shibata, Hajime; Niki, Shigeru

    2016-07-01

    The degradation mechanism of unencapsulated Cu(In,Ga)Se2 (CIGS) solar cells upon exposure to air has been investigated. Exposure to air at room temperature slightly reduces the conversion efficiency of CIGS solar cells. However, this conversion efficiency decreases significantly under damp heat testing at 85 °C and a relative humidity of 85% for 15 h. The shunt resistance and conversion efficiency are completely recovered after removing the side edges of the CIGS solar cells by mechanical scribing. This result suggests that low-resistive layers are formed on the sidewalls of the solar cells during damp heat testing. In addition, alkaline solution etching has been confirmed to be an effective way of removing the low-resistive layers. The low-resistive layers on the sidewalls are identified to be molybdenum oxides and sodium molybdate by Auger electron spectroscopy. After etching the oxides on the sidewalls, the saturation current density and ideality factor are confirmed to be improved.

  15. Experimental study of heat transfer and thermal performance with longitudinal fins of solar air heater

    Science.gov (United States)

    Chabane, Foued; Moummi, Noureddine; Benramache, Said

    2013-01-01

    The thermal performance of a single pass solar air heater with five fins attached was investigated experimentally. Longitudinal fins were used inferior the absorber plate to increase the heat exchange and render the flow fluid in the channel uniform. The effect of mass flow rate of air on the outlet temperature, the heat transfer in the thickness of the solar collector, and the thermal efficiency were studied. Experiments were performed for two air mass flow rates of 0.012 and 0.016 kg s−1. Moreover, the maximum efficiency values obtained for the 0.012 and 0.016 kg s−1 with and without fins were 40.02%, 51.50% and 34.92%, 43.94%, respectively. A comparison of the results of the mass flow rates by solar collector with and without fins shows a substantial enhancement in the thermal efficiency. PMID:25685486

  16. Performance estimation of artificially roughened solar air heater duct provided with continuous ribs

    Directory of Open Access Journals (Sweden)

    Mridul Sharma, Varun

    2010-09-01

    Full Text Available The use of an artificial roughness on a surface is an effective technique to enhance the rate of heat transfer to fluid flow in the duct of a solar air heater. This paper presents a comparison of exergetic performance of solar air heaters having different types of geometry of roughness elements (continuous ribs on the absorber plate. The exergy efficiency has been computed by using the correlations for heat transfer and friction factor developed by various investigators within the investigated range of operating and system parameters. The exergy efficiency based criterion shows the better results at lower value of Re. There is not a single roughness geometry which gives best exergetic performance for whole range of Reynolds number. Solar air heater having rib-grooved and arc shaped wire as artificial roughness is found to have better exergy efficiency in the lower range of Reynolds number. However, smooth duct is found suitable in the higher range of Reynolds number.

  17. Performance estimation of artificially roughened solar air heater duct provided with continuous ribs

    Energy Technology Data Exchange (ETDEWEB)

    Mridul Sharma, Varun [Department of Mechanical Engineering, National Institute of Technology, Hamirpur, 177005 (India)

    2010-07-01

    The use of an artificial roughness on a surface is an effective technique to enhance the rate of heat transfer to fluid flow in the duct of a solar air heater. This paper presents a comparison of exergetic performance of solar air heaters having different types of geometry of roughness elements (continuous ribs) on the absorber plate. The exergy efficiency has been computed by using the correlations for heat transfer and friction factor developed by various investigators within the investigated range of operating and system parameters. The exergy efficiency based criterion shows the better results at lower value of Re. There is not a single roughness geometry which gives best exergetic performance for whole range of Reynolds number. Solar air heater having rib-grooved and arc shaped wire as artificial roughness is found to have better exergy efficiency in the lower range of Reynolds number. However, smooth duct is found suitable in the higher range of Reynolds number.

  18. Pengaruh Penambahan Glukosa Sebagai Co-substrate dalam Pengolahan Air Limbah Minyak Solar Menggunakan Sistem High Rate Alga Reactor (HRAR)

    OpenAIRE

    Laksmisari Rakhma Putri; Agus Slamet; Joni Hermana

    2014-01-01

    Kandungan minyak dalam air limbah umumnya relatif sulit untuk diuraikan oleh mikroorganisme pada pengolahan air limbah secara biologis. Sistem alga dalam High Rate Alga Reactor (HRAR) telah banyak dikembangkan dan digunakan sebagai pengolah air limbah domestik dan industri. Aplikasi sistem alga dalam HRAR ini dicoba untuk diaplikasikan dalam pengolahan air limbah mengandung minyak solar. Penelitian dilakukan untuk mengkaji kemampuan HRAR dalam menurunkan kandungan minyak solar dengan penambah...

  19. Combination of experimental and simulated small scale solar air-conditioning system

    OpenAIRE

    Thomas, Sébastien; Hennaut, Samuel; Andre, Philippe

    2010-01-01

    It is now clearly assumed that solar assisted air conditioning is able to decrease CO2 production of building operation. One way to evaluate the energy savings potential is the simulation of airconditioning systems. On the other hand, it is also crucial to assess system performance by experimentations. The operation of a solar cooling system in its real environment is considered here. The objective is to evaluate if sun radiation in our region (Western Europe – Belgium) in summ...

  20. Air emissions due to wind and solar power.

    Science.gov (United States)

    Katzenstein, Warren; Apt, Jay

    2009-01-15

    Renewables portfolio standards (RPS) encourage large-scale deployment of wind and solar electric power. Their power output varies rapidly, even when several sites are added together. In many locations, natural gas generators are the lowest cost resource available to compensate for this variability, and must ramp up and down quickly to keep the grid stable, affecting their emissions of NOx and CO2. We model a wind or solar photovoltaic plus gas system using measured 1-min time-resolved emissions and heat rate data from two types of natural gas generators, and power data from four wind plants and one solar plant. Over a wide range of renewable penetration, we find CO2 emissions achieve approximately 80% of the emissions reductions expected if the power fluctuations caused no additional emissions. Using steam injection, gas generators achieve only 30-50% of expected NOx emissions reductions, and with dry control NOx emissions increase substantially. We quantify the interaction between state RPSs and NOx constraints, finding that states with substantial RPSs could see significant upward pressure on NOx permit prices, if the gas turbines we modeled are representative of the plants used to mitigate wind and solar power variability.

  1. Indoor tests of a hot-air solar collector

    Science.gov (United States)

    1979-01-01

    Data taken relating indoor testing using solar simulator at Marshall Space Center has been compared with data taken during outdoor tests in previous studies. Data includes tests on thermal performance, time constance, and incidence-angle modifier tests in table/graph form.

  2. Long term weathering effects on the thermal performance of the solaron (air) solar collector

    Science.gov (United States)

    1979-01-01

    The test procedures and the results obtained during the evaluation test program on the Solaron Corporation air-type solar collector are presented. The tests were performed under simulated conditions, following long-term exposure to natural weathering conditions. The Solaron Model 2001, air-type solar collector has a gross area of 19 square feet and the weight is 160 pounds. The absorber plate is made of 24-gage steel, the coating is baked-on black paint, the cover consists of two sheets of 1/8-inch low-iron tempered glass, and the insulation is one thickness of 3 5/8-inch fiberglass batting.

  3. Potential of roof-integrated solar collectors for preheating air at drying facilities in Northern Thailand

    Energy Technology Data Exchange (ETDEWEB)

    Roman, Franz; Nagle, Marcus; Leis, Hermann; Mueller, Joachim [Institute of Agricultural Engineering 440e, University of Hohenheim, Garbenstrasse 9, 70599 Stuttgart (Germany); Janjai, Serm [Department of Physics, Silpakorn University, Nakhon Pathom (Thailand); Mahayothee, Busarakorn [Department of Food Technology, Silpakorn University, Nakhon Pathom (Thailand); Haewsungcharoen, Methinee [Department of Food Engineering, Chiang Mai University, Chiang Mai (Thailand)

    2009-07-15

    Longan is one of the most widely cropped fruits in Northern Thailand, where a significant amount of the annual harvest is commercially dried and exported as a commodity. Liquefied petroleum gas is generally used as the energy source for heating the drying air, but concern is growing as fuel prices are expected to increase for the foreseeable future. Meanwhile, with the ample solar radiation in Thailand, the roofs of drying facilities could be adapted to serve as solar collectors to preheat the drying air, thus reducing the energy requirement from fossil fuels. In this study, a simulation program for a flat-plate solar air heater was used to estimate the potential to preheat drying air given the conditions of several longan drying facilities. Results showed that solar collectors can replace up to 19.6% of the thermal energy demand during the drying season. Bigger collectors and smaller air channels result in more useful heat, but attention has to be paid to costs and pressure drop, respectively. Annual monetary savings can reach up to THB 56,000 ({approx}US$ 1800 at US$ 1 THB 31). (author)

  4. Simulation and Optimization of a Solar Driven Air Conditioning System for Indian Cities

    OpenAIRE

    Sharma, Dev

    2013-01-01

    Simulation and Optimization of a Solar Driven Air Conditioning System for Indian Cities Conventional air-conditioners need high grade energy i.e. electricity, which in India, is primarily produced from fossil fuels. In spite of several emission restraints exercised by many countries under Kyoto protocol, energy consumption and pollution levels are higher than ever. Therefore, an assessment from the ecological point of view needs to be implemented as the greenhouse gases effect remains a threa...

  5. Performance of perforated and unprotected solar air heaters to reduce the ventilation heat load of livestock shelters

    Energy Technology Data Exchange (ETDEWEB)

    Cordeau, S.; Barrington, S. [McGill Univ., Ste. Anne de Bellevue, PQ (Canada). Macdonald College, Dept. of Bioresource Engineering

    2009-07-01

    This paper discussed the use of solar radiation as a sustainable heat source for applications that need only a limited amount of energy. It reported on a study that evaluated the efficiency of a new design in solar air heaters for heating cold fresh air in livestock shelters. The heater consisted of an unprotected perforated black corrugated siding where the incoming fresh ventilation air picks up heat from the face and the back of the solar collector. The performance of 6 solar air heaters installed in 2 barns in rural Quebec was monitored over two years. A weather station was used to monitor the radiation energy absorbed on a vertical plane parallel to the solar air heaters; the outside air temperature; relative humidity; wind speed; and wind direction. Sensors inside the building were used to monitor the average building air temperature; relative humidity; temperature of the incoming fresh air heated by the solar collectors; and the outgoing air temperature. The study showed that performance of this unprotected type of solar air heater is very sensitive to wind velocity. The efficiency of the solar air heaters was more than 70 per cent only under low wind conditions of 1 m/s. For winds of more than 3 m/s, the efficiency quickly dropped below 20 per cent. During the month of March, the solar air heaters increased the temperature of the incoming cold fresh air by an average of 8 degrees C under an efficiency of 20 per cent, as compared to 4 degrees C for the months of November to February under an efficiency of 25 to 40 per cent.

  6. A packed bed dehumidifier/regenerator for solar air conditioning with liquid desiccants

    Science.gov (United States)

    Factor, H. M.; Grossman, G.

    1980-01-01

    A packed column air-liquid contactor has been studied in application to air dehumidification and regeneration in solar air conditioning with liquid desiccants. A theoretical model has been developed to predict the performance of the device under various operating conditions. Computer simulations based on the model are presented which indicate the practical range of air to liquid flux ratios and associated changes in air humidity and desiccant concentration. An experimental apparatus has been constructed and experiments performed with Monoethylene Glycol (MEG) and Lithium Bromide as desiccants. MEG experiments have yielded inaccurate results and have pointed out some practical problems associated with the use of Glycols. LiBr experiments show very good agreement with the theoretical model. Preheating of the air is shown to greatly enhance desiccant regeneration. The packed column yields good results as a dehumidifier/regenerator, provided pressure drop can be reduced with the use of suitable packing.

  7. Thermal performance in layer hen house with natural acclimatization/ Desempenho térmico de aviário de postura acondicionado naturalmente

    Directory of Open Access Journals (Sweden)

    Luiz Antônio Targa

    2008-08-01

    Full Text Available The work aimed at presenting analyses and comparisons of the thermal performance of a laying hens housing in the region of Bastos, in the state of São Paulo, adapted from natural alternatives of acclimatization, having a not adapted housing as reference, that is, of a more common typology in the area, and another one, artificially acclimatized. The index evaluated was the temperature and humidity (THI, the black globe temperature and humidity index (GTHI and the thermal radiation charge (TRC. It was calculated from the measurement of the temperature of dry bulb, temperature of wet bulb, temperature of black globe and air speed. The measurements were made both in the intern and the extern environment, at four times (5 a.m, 11a.m., 3 p.m. and 4 p.m. o´clock and in two seasons (late spring and early summer, for ten days in a row. The results allow to conclude that the house naturally acclimatized (NA has presented intermediate performance as compared with the others, making it to possible to control environment at adequate levels only during spring.O objetivo do trabalho foi apresentar análises e comparações sobre o desempenho térmico de um galpão para aves de postura, na região de Bastos, estado de São Paulo, adaptado a partir de alternativas naturais de acondicionamento, tendo como referências um galpão não adaptado, ou seja, de tipologia mais comum na região e outro acondicionado artificialmente. Os parâmetros avaliados – Índice de Temperatura e Umidade (ITU, o Índice de Temperatura de Globo Negro (UTGU, Umidade e a Carga Térmica de Radiação (CTR – foram calculados a partir de medidas de temperatura de bulbo seco, temperatura de bulbo úmido, temperatura de globo negro e velocidade do ar. As medições foram realizadas, nos ambientes internos e externos, em quatro horários (5, 11, 15 e 16 horas na estação primavera e verão, durante dez dias consecutivos. Os resultados obtidos permitiram concluir que o sistema de

  8. Homogeneous and Inhomogeneous Model for Flow and Heat Transfer in Porous Materials as High Temperature Solar Air Receivers

    OpenAIRE

    Smirnova, Olena; Fend, Thomas; Schwarzbözl, Peter; Schöllgen, Daniel

    2010-01-01

    Results of calculations on flow and heat transfer in a porous Silicon Carbide honeycomb structure applied as a solar air receiver are presented. In this application porous materials are put in concentrated solar radiation. Flux densities of up to 1000 MW/m² are reached. Simultaneously, ambient air flows through the material to be heated up to temperatures of app. 800°C. This hot air is then used to feed the steam generator of a steam turbine to generate solar electricity (solar tower technolo...

  9. Air Quality Improvements of Increased Integration of Renewables: Solar Photovoltaics Penetration Scenarios

    Science.gov (United States)

    Duran, P.; Holloway, T.; Brinkman, G.; Denholm, P.; Littlefield, C. M.

    2011-12-01

    Solar photovoltaics (PV) are an attractive technology because they can be locally deployed and tend to yield high production during periods of peak electric demand. These characteristics can reduce the need for conventional large-scale electricity generation, thereby reducing emissions of criteria air pollutants (CAPs) and improving ambient air quality with regard to such pollutants as nitrogen oxides, sulfur oxides and fine particulates. Such effects depend on the local climate, time-of-day emissions, available solar resources, the structure of the electric grid, and existing electricity production among other factors. This study examines the air quality impacts of distributed PV across the United States Eastern Interconnection. In order to accurately model the air quality impact of distributed PV in space and time, we used the National Renewable Energy Lab's (NREL) Regional Energy Deployment System (ReEDS) model to form three unique PV penetration scenarios in which new PV construction is distributed spatially based upon economic drivers and natural solar resources. Those scenarios are 2006 Eastern Interconnection business as usual, 10% PV penetration, and 20% PV penetration. With the GridView (ABB, Inc) dispatch model, we used historical load data from 2006 to model electricity production and distribution for each of the three scenarios. Solar PV electric output was estimated using historical weather data from 2006. To bridge the gap between dispatch and air quality modeling, we will create emission profiles for electricity generating units (EGUs) in the Eastern Interconnection from historical Continuous Emissions Monitoring System (CEMS) data. Via those emissions profiles, we will create hourly emission data for EGUs in the Eastern Interconnect for each scenario during 2006. Those data will be incorporated in the Community Multi-scale Air Quality (CMAQ) model using the Sparse Matrix Operator Kernel Emissions (SMOKE) model. Initial results indicate that PV

  10. Research on performance of mixed absorption refrigeration for solar air-conditioning

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A novel lithium bromide/water mixed absorption refrigeration cycle that is suitable for the utilization of solar air-conditioning and can overcome the drawbacks of low system overall efficiency of traditional solar absorption refrigeration air-condition systems is presented.The accessorial high pressure generator was added in the cycle.The lithium bromide solution flowing out from the high pressure generator was mixed with the solution from the low pressure absorber to increase lithium bromide solution concentration and decrease pressure in the high pressure absorber.The performance of a mixed absorption refrigeration cycle was analyzed.The theoretical analysis shows that the highest COP is 0.61,while the highest available temperature difference of heat resource is 33.2℃.The whole coefficient of performance of the solar air-conditioning using mixed absorption cycle is 94.5% higher than that of two-stage absorption.The advantages of solar air-conditioning can be markedly made use of by the cycle.

  11. Hot-air flat-plate solar collector-design package

    Science.gov (United States)

    1979-01-01

    Report contains design data, performance specifications, and drawings for hot-air flat-plate solar-energy collector. Evaluation consists of tests on thermal performance time constance, and incidence angle modifier test. Results are presented in table and graph form and are analyzed in detail.

  12. Energy and Greenhouse Gas Emission Assessment of Conventional and Solar Assisted Air Conditioning Systems

    Directory of Open Access Journals (Sweden)

    Xiaofeng Li

    2015-11-01

    Full Text Available Energy consumption in the buildings is responsible for 26% of Australia’s greenhouse gas emissions where cooling typically accounts for over 50% of the total building energy use. The aim of this study was to investigate the potential for reducing the cooling systems’ environmental footprint with applications of alternative renewable energy source. Three types of cooling systems, water cooled, air cooled and a hybrid solar-based air-conditioning system, with a total of six scenarios were designed in this work. The scenarios accounted for the types of power supply to the air-conditioning systems with electricity from the grid and with a solar power from highly integrated building photovoltaics (BIPV. Within and between these scenarios, systems’ energy performances were compared based on energy modelling while the harvesting potential of the renewable energy source was further predicted based on building’s detailed geometrical model. The results showed that renewable energy obtained via BIPV scenario could cover building’s annual electricity consumption for cooling and reduce 140 tonnes of greenhouse gas emissions each year. The hybrid solar air-conditioning system has higher energy efficiency than the air cooled chiller system but lower than the water cooled system.

  13. Heat transfer performance analysis of a multi channel volumetric air receiver for solar power tower

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Eui Guk [LG Electronics Inc., Daejeon (Korea, Republic of)

    2012-03-15

    In this study, a heat transfer performance analysis is carried out for a multi channel volumetric air receiver for a solar power tower. On the basis of a series of reviews regarding the relevant literature, a calculation process is proposed for the prediction of the wall and air temperature distributions of a single channel at given geometric and input conditions. Furthermore, a unique mathematical model of the receiver effectiveness is presented through analysis of the temperature profile. The receiver is made of silicon carbide. A total of 225 square straight channels per module are molded to induce the air flow, and each channel has the dimensions of 2mm(W)x2mm(H)x0.2mm(t)x320mm(L). The heat transfer rate, temperature distribution and effectiveness are presented according to the variation of the channel and module number under uniform irradiation and mass flow rate. The available air outlet temperature applied to the solar power tower should by over 700 .deg. C. This numerical model was actually used in the design of a 200kw level commercial solar air receiver, and the required number of modules satisfying the thermal performance could be obtained for the specified geometric and input conditions.

  14. Design and fabrication of a cost effective solar air heater for Bangladesh

    Energy Technology Data Exchange (ETDEWEB)

    Wazed, M.A.; Nukman, Y. [Department of Engineering Design and Manufacture, University of Malaya (UM), 50603 Kuala Lumpur (Malaysia); Islam, M.T. [Department of Mechanical Engineering, Chittagong University of Engineering and Technology (CUET), Chittagong 4349 (Bangladesh)

    2010-10-15

    In this research, a solar air heater is designed, fabricated and its performance is assessed in the perspective of an emerging/developing country with a huge energy demand like Bangladesh. The winter season (mid-November-mid-February) of the country characterizes by low temperatures, cool air blowing from the west or northwest, clear sky and meager rainfall. Minimum temperature in the extreme northwest in late December and early January sometimes reaches 3 C and day length is about 10 h. The shortness of winter days can be compensated by reducing the heat loss during long nights. The solar air heater is constructed to prevent as much heat loss as possible. In other words, the heating of air is accomplished by maximizing light gain and minimizing heat loss. It is observed that the fabricated solar air heater is working efficiently. The maximum room temperature and the temperature difference from ambient are 45.5 C and 12.25 C for forced circulation and 41.75 C and 8.5 C for natural circulation respectively. The experimental outlet temperatures have been compared with that of theoretical values. Due to its low-cost and simple technology, it is affordable in all aspects, viz. of cost, operation and maintenance by the typical people of Bangladesh. (author)

  15. Characteristics of exhaust air facades as solar absorbers for saving of heating energy

    Science.gov (United States)

    Voncube, H. L.; Ludwig, E.

    1982-12-01

    The solar radiation exploited by solar exhaust air windows was measured at a building facing four main directions. The windows were not constructed as optimal radiation absorbers and the heat gain stood in a range of 3 to 10% of the heat consumption, depending on time of year. Optimal windows (chiefly clear glass with Venetian blinds) were found by a computer program simulating the process of radiation in an exhaust air-window and heat gains up to 50% can be obtained. Relation to air flow rate and others were found. The calculated results were proved by measurements. With a suitable heating systems in the building (heat transport form south side to north side, heat storage) up to 50% of the annual consumption can be saved.

  16. An improved thermal and electrical model for a solar photovoltaic thermal (PV/T) air collector

    Energy Technology Data Exchange (ETDEWEB)

    Sarhaddi, F.; Farahat, S.; Ajam, H.; Behzadmehr, A.; Mahdavi Adeli, M. [Department of Mechanical Engineering, Shahid Nikbakht Faculty of Engineering, University of Sistan and Baluchestan, Zahedan 98164-161 (Iran)

    2010-07-15

    In this paper, an attempt is made to investigate the thermal and electrical performance of a solar photovoltaic thermal (PV/T) air collector. A detailed thermal and electrical model is developed to calculate the thermal and electrical parameters of a typical PV/T air collector. The thermal and electrical parameters of a PV/T air collector include solar cell temperature, back surface temperature, outlet air temperature, open-circuit voltage, short-circuit current, maximum power point voltage, maximum power point current, etc. Some corrections are done on heat loss coefficients in order to improve the thermal model of a PV/T air collector. A better electrical model is used to increase the calculations precision of PV/T air collector electrical parameters. Unlike the conventional electrical models used in the previous literature, the electrical model presented in this paper can estimate the electrical parameters of a PV/T air collector such as open-circuit voltage, short-circuit current, maximum power point voltage, and maximum power point current. Further, an analytical expression for the overall energy efficiency of a PV/T air collector is derived in terms of thermal, electrical, design and climatic parameters. A computer simulation program is developed in order to calculate the thermal and electrical parameters of a PV/T air collector. The results of numerical simulation are in good agreement with the experimental measurements noted in the previous literature. Finally, parametric studies have been carried out. Since some corrections have been down on thermal and electrical models, it is observed that the thermal and electrical simulation results obtained in this paper is more precise than the one given by the previous literature. It is also found that the thermal efficiency, electrical efficiency and overall energy efficiency of PV/T air collector is about 17.18%, 10.01% and 45%, respectively, for a sample climatic, operating and design parameters. (author)

  17. Air-liquid solar collector for solar heating, combined heating and cooling, and hot water subsystems

    Science.gov (United States)

    1978-01-01

    A collection of quarterly reports consisting of the installation and layout design of the air collector system for commercial applications, completion of the preliminary design review, detailed design efforts, and preparation of the verification test plan are given. Performance specifications and performance testing of a prototype model of a two manifold, 144 tube air collector array is presented.

  18. Solar energy contribution to the energy demand for air conditioning system in an office building under Tripoli climate conditions

    OpenAIRE

    Musbah Mohamed H.; Živković Branislav D.; Kosi Franc F.; Abdulgalil Mohamed M.; Sretenović Aleksandra A.

    2014-01-01

    The feasibility of solar assisted air conditioning in an office building under Tripoli weather conditions is investigated in this paper. A single-effect lithium bromide absorption cycle powered by means of flat-plate solar collectors was modeled in order to predict the potential of the solar energy share. The cooling load profile was generated by using an detailed hourly based program and Typical meteorological year for Tripoli. System performance and solar...

  19. Numerical analysis of flow in a solar heater of air packing with shavings; Analisis numerico del flujo en un calentador solar de aire empacado con viruta

    Energy Technology Data Exchange (ETDEWEB)

    Lopez C, Raymundo; Morales G, Juan R; Diaz C, Alen; Lara V, Araceli; Lizardi R, Arturo [Universidad Autonoma Metropolitana-Azcapotzalco, Mexico, D.F. (Mexico); Vaca M, Mabel [UNAM, Mexico, D.F. (Mexico)

    2000-07-01

    The temperature distribution of air through a solar heater is determined by means of the equations of heat, mass, momentum, and energy conservation. The solution is obtained by means of the numeric model of finite volume, using the CFC2000 software, V. 3.3. The studied flow is laminar. The temperature distribution resulted quite similar for different Reynolds numbers; the greatest difference was less than 4 Celsius degrees, for similar ranges of solar radiation. The influence of the separation that exists between the clear cover and the free surface of the material used as thermal summit (b) was analyzed. A difference up to 41 Celsius degrees for a Reynolds number of 1000 and values of b between 3 and 7 cm. For a Reynolds of 2000, the difference was of 29 Celsius degrees, in the same range of b. [Spanish] Se determinan la distribucion de temperaturas del aire, a lo largo de un calentador solar, aplicando las ecuaciones de conservacion de masa, cantidad de movimiento y energia. La solucion se obtiene con el modelo numerico de volumen finito y la utilizacion del programa de computadora llamado CFC2000 version 3.3. El flujo estudiado es del tipo laminar. La distribucion de temperaturas resulto ser muy semejante para diferentes valores del numero de Reynolds, la diferencia mayor resulto menor a 4 grados Celsius, para rangos similares de radiacion solar. Se analizo la influencia de la separacion que existe entre la cubierta transparente y la superficie libre del material que sirve como almacen termico (b). Se encontro una diferencia maxima de hasta 41 grados celsius para un numero de Reynolds de 1000 y los valores de b entre 3 y 7 cm. Cuando el Reynolds fue de 2000 la diferencia fue de 29 grados Celsius, en el mismo rango de b.

  20. Experimental investigation of three different solar air heaters: Energy and exergy analyses

    Energy Technology Data Exchange (ETDEWEB)

    Alta, Deniz; Ertekin, C.; Yaldiz, Osman [Department of Farm Machinery, Faculty of Agricultural Engineering, Akdeniz University, 07059 Antalya (Turkey); Bilgili, Emin [Cukurova Agricultural Research Institute, Adana (Turkey)

    2010-10-15

    The present study aims to compare three different types of designed flat-plate solar air heaters, two having fins (Type II and Type III) and the other without fins (Type I), one of the heater with a fin had single glass cover (Type III) and the others had double glass covers (Type I and Type II). The energy and exergy output rates of the solar air heaters were evaluated for various air flow rates (25, 50 and 100 m{sup 3}/m{sup 2} h), tilt angle (0 , 15 and 30 ) and temperature conditions versus time. Based on the energy and exergy output rates, heater with double glass covers and fins (Type II) is more effective and the difference between the input and output air temperature is higher than of the others. Besides, it is found that the circulation time of air inside the heater played a role more important than of the number of transparent sheet. Lower air flow rates should be preferred in the applications of which temperature differences is more important. (author)

  1. A review on the recent development of solar absorption and vapour compression based hybrid air conditioning with low temperature storage

    Directory of Open Access Journals (Sweden)

    Noor D. N.

    2016-01-01

    Full Text Available Conventional air conditioners or vapour compression systems are main contributors to energy consumption in modern buildings. There are common environmental issues emanating from vapour compression system such as greenhouse gas emission and heat wastage. These problems can be reduced by adaptation of solar energy components to vapour compression system. However, intermittence input of daily solar radiation was the main issue of solar energy system. This paper presents the recent studies on hybrid air conditioning system. In addition, the basic vapour compression system and components involved in the solar air conditioning system are discussed. Introduction of low temperature storage can be an interactive solution and improved economically which portray different modes of operating strategies. Yet, very few studies have examined on optimal operating strategies of the hybrid system. Finally, the findings of this review will help suggest optimization of solar absorption and vapour compression based hybrid air conditioning system for future work while considering both economic and environmental factors.

  2. Pengaruh Penambahan Glukosa Sebagai Co-substrate dalam Pengolahan Air Limbah Minyak Solar Menggunakan Sistem High Rate Alga Reactor (HRAR

    Directory of Open Access Journals (Sweden)

    Laksmisari Rakhma Putri

    2014-09-01

    Full Text Available Kandungan minyak dalam air limbah umumnya relatif sulit untuk diuraikan oleh mikroorganisme pada pengolahan air limbah secara biologis. Sistem alga dalam High Rate Alga Reactor (HRAR telah banyak dikembangkan dan digunakan sebagai pengolah air limbah domestik dan industri. Aplikasi sistem alga dalam HRAR ini dicoba untuk diaplikasikan dalam pengolahan air limbah mengandung minyak solar. Penelitian dilakukan untuk mengkaji kemampuan HRAR dalam menurunkan kandungan minyak solar dengan penambahan glukosa sebagai co-substrate. Penambahan co-substrate diperkirakan dapat mendorong bakteri untuk memberikan suplai karbondioksida pada mikroalga. Penelitian ini dilakukan dengan dua variabel penelitian yaitu konsentrasi minyak solar sebesar 381 ppm dan 830 ppm dalam air limbah dan konsentrasi co-substrate berupa gula sebesar 5 gram, 7 gram, dan 10 gram ke dalam 18 Liter air pada reaktor. Setiap dua hari sekali selama 14 hari akan diambil sampel untuk kemudian dilakukan analisis masing-masing parameter. Hasil menunjukkan bahwa efisiensi tertinggi kinerja HRAR dalam menurunkan kandungan minyak solar adalah sebesar 84,27%. Efisiensi tertinggi ini didapatkan pada reaktor dengan variasi penambahan minyak solar 830 ppm dan co-substrate sebesar 10 gram ke dalam 18 Liter yang memiliki nilai COD 586,67 mg/L. Pada konsentrasi minyak solar sebesar 830 ppm, penambahan co-substrate memberikan pengaruh pada efisiensi penurunan kandungan minyak solar. Semakin besar penambahan co-substrate, semakin besar efisiensi penurunan kandungan minyak solar.

  3. Reduced adverse effects on Si thin film solar cells caused by growth chamber air exposure

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Fan; Zhang, Lin; Zheng, Yi; Schimitt, Francimar; Tso, Alan; Li, Lipan; Tsuei, Lun; Yuan, Zheng; Shieh, Brian [Thin Film Solar Products Division, Applied Materials, Santa Clara, CA 95054 (United States)

    2010-06-15

    The cost of photovoltaic (PV) energy is reduced by increasing solar cell power conversion efficiency and decreasing manufacture cost. An effective way of lowering the cost of Si thin film solar cells (TFSC) is to grow panels on large-area substrates. In this paper we study the effect of air residual to Si TFSC grown on 5.7 m{sup 2} glass in plasma-enhanced chemical vapor deposition (PECVD) chambers. Structural and chemical analysis show that oxygen incorporated into the Si films behaved as impurity dopant in the hydrogenated microcrystalline Si ({mu}c-Si) layers and reduced the efficiency of amorphous Si (a-Si)/{mu}c-Si tandem junction solar cells when the film had oxygen concentration >2 x 10{sup 19} atoms/cm{sup 3}. Higher oxygen content further suppressed the {mu}c-Si crystallization. We found that hydrogen plasma treatment of process chamber before Si film deposition effectively reduced the adverse effects of air exposure and improved both film quality and solar cell performance. The hydrogen-treated chamber produced contamination-free, solar cells with consistent, initial efficiency >10%. (author)

  4. Determinación de Metales Pesados y Sales Solubles en Suelos de Cultivo Acondicionados con Lodos Residuales

    Directory of Open Access Journals (Sweden)

    Silvia Ruth Paredes Reyes

    2001-01-01

    Full Text Available Este proyecto tiene por objeto realizar una determinación de metales pesados (Pb, Cd, Cr, Zn y sales solubles de Na, K, Mg y Ca en suelos de cultivo del rancho "La Xaropa" acondicionados con lodos residuales de la Planta de Tratamiento Municipal de Aguascalientes. De la misma manera realizar las mismas determinaciones en tierras de cultivo que no han sido reactivadas con lodos, esto es con el propósito de comparar dos condiciones diferentes. Es importante conocer la presencia de metales pesados porque son tóxicos para los organismos, ya que alteran su metabolismo y pueden provocar su muerte. Los metales pesados, pueden pasar de la tierra hacia el organismo del hombre, a través de la cadena alimenticia provocando graves problemas de salud. La utilización de los lodos puede contribuir a aumentar la salinidad del mismo y disminuir su fertilidad. Las determinaciones se llevaron a cabo utilizando el método espectrofotométrico de absorción atómica. Los resultados muestran que se encontró un incremento en el contenido de cromo y zinc. En tierras de cultivo sin lodos adicionados se encontraron 627.43 Kg/ha y en las tierras acondicionadas con lodos 780. 95 Kg/ ha. Los resultados de zinc en tierras sin lodo adicionado muestran 394.27 Kg/ha. Y en tierras con lodos 398. 1 1 K/ha. Los resultados de la determinación de sales solubles también muestran incremento en la concentración de las mismas.

  5. Experimental and Theoretical Study for Performance Enhancement of Air Solar Collectors by Using Different Absorbers

    Directory of Open Access Journals (Sweden)

    Ahmed A. Mohammad Saleh

    2016-09-01

    Full Text Available An experimental and theoretical study has been done to investigate the thermal performance of different types of air solar collectors, In this work air solar collector with a dimensions of (120 cm x90 cm x12 cm , was tested under climate condition of Baghdad city with a (43° tilt angel by using the absorber plate (1.45 mm thickness, 115 cm height x 84 cm width, which was manufactured from iron painted with a black matt. The experimental test deals with five types of absorber:- Conventional smooth flat plate absorber , Finned absorber , Corrugated absorber plate, Iron wire mesh on absorber And matrix of porous media on absorber . The hourly and average efficiency of the collectors were investigated for three values of mass flow rates (0.016 kg/s to 0.027 kg/s for each type of collector and then the porosity for the last collector type was tested by changing the porosity of porous media. A typical air solar collector has been studied Theoretically to build a standard software for testing any type of air solar collectors with local weather data . From the experimental study it can be seen by using some obstacle material to the air flow (fins, corrugated absorber plate, iron wire mesh porous media on the absorber could be enhanced the efficiencies not less than 4 % for finned type and 8 % for corrugated and 25 % for mesh and 30 % for porous media comparing with flat plate (smooth collector . Theoretically, the results showed that the collector with high convention heat transfer coefficient porous media has high hourly efficiency about (η = 56 % and iron wire mesh on absorber ( η = 52 % , on the other side the minimum performance occurred in the flat plate absorber (η = 28 %. Comparison of results reveals that the theoretical predictions agree reasonably well with experimental results. And the difference between the theoretical and experimental efficiency in general was between (1─ 15 %.

  6. Efficient and stable perovskite solar cells prepared in ambient air irrespective of the humidity

    OpenAIRE

    Tai, Qidong; You, Peng; Sang, Hongqian; Liu, Zhike; Hu, Chenglong; Chan, Helen L. W.; Yan, Feng

    2016-01-01

    Poor stability of organic–inorganic halide perovskite materials in humid condition has hindered the success of perovskite solar cells in real applications since controlled atmosphere is required for device fabrication and operation, and there is a lack of effective solutions to this problem until now. Here we report the use of lead (II) thiocyanate (Pb(SCN)2) precursor in preparing perovskite solar cells in ambient air. High-quality CH3NH3PbI3−x (SCN) x perovskite films can be readily prepare...

  7. Solar-aided air conditioning through sorption. Final report. Phase 2; Solar unterstuetzte Klimatisierung ueber Sorption. Endbericht zur Phase 2

    Energy Technology Data Exchange (ETDEWEB)

    Laevemann, E.; Kessling, W.; Peltzer, M.

    1996-09-24

    The present article reports on possibilities of using solar energy for cooling buildings. It contains the following chapters: Current state of research and development; room air conditioning; planning and results of the studies; theory; experimental studies on the sorption dehumidifier; development of exchange surfaces; development of solution distributors; cooling of exchange surfaces; construction of a sorption dehumidifier. (HW) [Deutsch] Die Arbeit berichtet ueber Moeglichkeiten der Anwendung von Solarenergie zur Kuehlung von Gebaeuden. Die Arbeit enthaelt folgende Kapitel: - Stand der Forschung und Entwicklung - Raumklimatisierung - Planung und Ergebnis der Untersuchungen - Theorie - Experimentelle Untersuchungen am Sorptionsentfeuchter - Entwicklung von Austauschflaechen - Entwicklung von Loesungsverteilern - Kuehlung von Austauschflaechen - Konstruktion eines Sorptionsentfeuchters. (HW)

  8. Solar air heating systems. IEA solar heating and cooling programme - task 19. Final report; Luftsolvarmesystemer. Dansk deltagelse i IEA task 19. Slutrapport

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-10-01

    This project focuses on tools for analysis, development and optimization of systems and buildings with solar air-based heating systems. The results are collected in engineering handbook and in a `case study book` with examples of solar-heated buildings. The latter book is addressed to the architects as the primary target group. A component catalog for solar heating systems has been collected and will be published in the same time as the two handbooks. (EG)

  9. Employing exergy-optimized pin fins in the design of an absorber in a solar air heater

    Energy Technology Data Exchange (ETDEWEB)

    Nwosu, Nwachukwu P. [National Centre for Energy Research and Development (NCERD) and Department of Mechanical Engineering, University of Nigeria, Nsukka (UNN) (Nigeria)

    2010-02-15

    Fins serve as heat transfer augmentation features in solar air heaters; however, they increase pressure drop in flow channels. Pin fins are relatively good heat transfer augmentation features with superior aerodynamic performance, and as a result find application in some solar air heaters. The exergy optimization method is employed in sizing the pin fin. Results indicate that high efficiency of the optimized fin improves the heat absorption and dissipation potential of a solar air heater. With optimum fin efficiency and superior absorptive coating quality, useful energy losses can be minimized. Some important observations pertinent in design are made. (author)

  10. Efek Durasi Pencahayaan Pada Sistem HRAR Untuk Menurunkan Kandungan Minyak Solar Dalam Air Limbah

    Directory of Open Access Journals (Sweden)

    Dian Puspitasari

    2014-09-01

    Full Text Available Kandungan minyak di dalam air limbah industri perminyakan umumnya bersifat toksik terhadap mikroorganisme dan mengganggu proses pengolahan secara biologis. Sistem HRAR diperkirakan dapat mengatasi hambatan tersebut melalui proses fotosintesis untuk menghasilkan oksigen yang dibutuhkan mikroorganisme dalam mendegradasi senyawa hidrokarbon. Penelitian ini bertujuan mengkaji pengaruh perpanjangan waktu pencahayaan pada kemampuan HRAR dalam menurunkan kandungan minyak di dalam limbah. Variabel yang digunakan pada penelitian ini adalah variasi durasi pencahayaan dan variasi penambahan volume minyak solar yang ditambahkan ke dalam reaktor. Variasi durasi pencahayaan yang digunakan adalah pencahayaan selama 12 jam dan pencahayaan selama 24 jam. Sedangkan penambahan volume minyak solar ke dalam masing-masing reaktor adalah sebesar 346 ppm, 519 ppm dan 692 ppm. Hasil yang didapatkan dari penelitian ini adalah durasi pencahayaan selama 12 jam memiliki efek yang lebih baik terhadap penurunan konsentrasi minyak dibandingkan pencahayaan selama 24 jam. Hal ini dapat terlihat dari baiknya pertumbuhan alga dan bakteri di dalam reaktor serta tingginya penurunan konsentrasi minyak solar di dalamnya. Penurunan konsentrasi minyak solar terbaik terdapat pada reaktor dengan penambahan minyak solar sebesar 346 ppm. Pada reaktor dengan durasi pencahayaan selama 12 jam terjadi penurunan konsentrasi minyak sebesar 78,4%. Sedangkan penurunan kandungan minyak solar pada reaktor dengan durasi pencahayaan selama 24 jam adalah sebesar 73,9%.

  11. Theoretical and Experimental Investigations of Cylindrical Air-Heating Solar Collector

    Science.gov (United States)

    Pelece, I.; Shipkovs, P.

    2016-06-01

    Solar energy is used not only at low latitudes, where it is available at large amounts, but also at higher latitudes, where height of sun and irradiance are significantly lower. On the other hand, the length of day at higher latitudes is longer in summer than at low latitudes, and also the path of the sun is longer. The present research deals with seeking for new shapes of solar collectors capable of receiving more solar energy. For designing and evaluating new shapes of solar collectors, it is necessary to have new methods for simple calculations of energy received from the sun by surface of any shape and direction. Such a method is explained in the present paper. Based on calculations by the proposed method, a new form of solar collector - a cylindrical collector - has been worked out. This collector is intended for air heating, but main principles can also be used for water heating, and even for photovoltaics. A cylindrical collector receives more energy in the morning and evening than a flat one, but at midday power of both collectors is equal, if effective areas are equal. Daily energy sum of the cylindrical solar collector is 1.5 times greater than that of the flat one.

  12. A theoretical investigation to study the effect of air pollution on global solar radiation

    International Nuclear Information System (INIS)

    The ratio of measured solar radiation for normal and clear sky G and G0, known an ''clearness index'' is as an indicator for air pollutant mass loading. In the present work, estimated clear sky global solar radiation G0 for cairo city is compared graphically with measured actual solar radiation G for normal sky with atmospheric aerosols and pollution. The clearness index (G/G0) and its empirical coefficients which vary from place to place to place are examined in order to derive a suitable formula for cairo city relating these coefficients. In this study, the well known angstrom equation in its linear form together with measured monthly means of the daily global solar radiation data are used for function fitting procedure to derive a linear semi-empirical formula relating the clearness ined coefficients (the error is of value 5%). For daily values of measured global solar radiation, an extension of the angstrom equation in a non-linear form is assumed and a polynomial regression is used for curve fitting to obtain a corresponding semi-empirical relation between the clearness index coefficients (the error is 3%). The paper ends with the result that the nonlinear graph seems to be reasonably accurate and is recommended to estimate the global solar radiation G for Cairo city

  13. Measuring Air Temperature in Glazed Ventilated Facades in the Presence of Direct Solar Radiation

    DEFF Research Database (Denmark)

    Kalyanova, Olena; Zanghirella, Fabio; Heiselberg, Per;

    2007-01-01

    part of the complete ventilation system. Assessment of necessary cooling/heating loads and of the whole building energy performance will then depend on the accuracy of measured air temperature. The presence of direct solar radiation is an essential element for the façade operation, but it can heavily...... irradiance, in order to achieve an accurate and reliable way to measure the air temperature reducing the error caused by radiation. Experiments include bare thermocouple, naturally and mechanically ventilated shielded thermocouples, mechanically ventilated thermocouple with double shielding, silver coated...

  14. Solar desiccant air-conditioning. Practical experience regarding operation and performance

    Energy Technology Data Exchange (ETDEWEB)

    Haller, A.; Trinkl, C.; Wittmann, R.; Zoerner, W. [Ingolstadt Univ. of Applied Sciences (Germany). Kompetenzzentrum Solartechnik; Hanby, V. [De Montfort Univ., Leicester (GB). Inst. of Energy and Sustainable Development (IESD)

    2007-07-01

    The Kompetenzzentrum Solartechnik of Ingolstadt University of Applied Sciences (Centre of Excellence for Solar Engineering) investigates the renewable-only based HVAC system of a multipurpose building. The 10.000 m{sup 2} gross floor area building is part of the biggest logistic-centre in the region serving the AUDI automobile production facilities. On the one hand, the investigation is supposed to demonstrate the potential of solar-assisted cooling, on the other hand, the monitoring, financed by the Bavarian Ministry of Environmental Affairs, focuses on the total energy balance of the building and the various innovative building technologies. Next to a ground source heat pump plant for base-load heating and cooling, the building is equipped with two arrays of solar-thermal flat-plate collectors (100 m{sup 2} of Conergy, Germany, and 180 m{sup 2} of Solahart, Australia) and a desiccant air-conditioning system (DEC, WOLF Anlagen-Technik, Germany). This consists of two plants with an air flow of 8.000 m{sup 3}/h and a nominal cooling capacity of 42 kW each. One of the two plants is monitored. The plant itself is considered a black box in a first approach, i.e. all incoming and outgoing energy flows and the air condition are measured. Apart from the investigation of the performance of the solar-assisted air-conditioning system, the feasibility of DEC-operation using flat-plate collectors available on the market is investigated. (orig.)

  15. Collector Efficiency in Downward-Type Internal-Recycle Solar Air Heaters with Attached Fins

    OpenAIRE

    Chii-Dong Ho; Ho-Ming Yeh

    2013-01-01

    The internal-recycle operation effect on collector efficiency in downward-type rectangular solar air heaters with attached fins is theoretically investigated. It is found that considerable collector efficiency is obtainable if the collector has attached fins and the operation is carried out with internal recycling. The recycling operation increases the fluid velocity to decrease the heat transfer resistance, compensating for the undesirable effect of decreasing the heat transfer driving force...

  16. Simulation based energy consumption calculation of an office building using solar-assisted air conditioning

    OpenAIRE

    Thomas, Sébastien; Andre, Philippe

    2008-01-01

    To minimize environmental impact and CO2 production associated with air-conditioning system operation, it is reasonable to evaluate the prospects of a clean energy source. The targets of the study are to evaluate cooling energy consumption to maintain thermal comfort in an office building and to point out solar energy to satisfy these cooling needs. Simulations were carried out with three different cooling systems in the same operating conditions to determine as accurately as possible the pot...

  17. An air-based corrugated cavity-receiver for solar parabolic trough concentrators

    International Nuclear Information System (INIS)

    Highlights: • We analyze a novel tubular cavity-receiver for solar parabolic trough collectors. • Four-fold solar concentration ratio is reached compared to conventional receivers. • Efficient operation at up to 500 °C is possible. • The pumping power requirement is found to be acceptably low. - Abstract: A tubular cavity-receiver that uses air as the heat transfer fluid is evaluated numerically using a validated heat transfer model. The receiver is designed for use on a large-span (9 m net concentrator aperture width) solar parabolic trough concentrator. Through the combination of a parabolic primary concentrator with a nonimaging secondary concentrator, the collector reaches a solar concentration ratio of 97.5. Four different receiver configurations are considered, with smooth or V-corrugated absorber tube and single- or double-glazed aperture window. The collector’s performance is characterized by its optical efficiency and heat loss. The optical efficiency is determined with the Monte Carlo ray-tracing method. Radiative heat exchange inside the receiver is calculated with the net radiation method. The 2D steady-state energy equation, which couples conductive, convective, and radiative heat transfer, is solved for the solid domains of the receiver cross-section, using finite-volume techniques. Simulations for Sevilla/Spain at the summer solstice at solar noon (direct normal solar irradiance: 847 W m−2, solar incidence angle: 13.9°) yield collector efficiencies between 60% and 65% at a heat transfer fluid temperature of 125 °C and between 37% and 42% at 500 °C, depending on the receiver configuration. The optical losses amount to more than 30% of the incident solar radiation and constitute the largest source of energy loss. For a 200 m long collector module operated between 300 and 500 °C, the isentropic pumping power required to pump the HTF through the receiver is between 11 and 17 kW

  18. Efficient and stable perovskite solar cells prepared in ambient air irrespective of the humidity

    Science.gov (United States)

    Tai, Qidong; You, Peng; Sang, Hongqian; Liu, Zhike; Hu, Chenglong; Chan, Helen L. W.; Yan, Feng

    2016-04-01

    Poor stability of organic-inorganic halide perovskite materials in humid condition has hindered the success of perovskite solar cells in real applications since controlled atmosphere is required for device fabrication and operation, and there is a lack of effective solutions to this problem until now. Here we report the use of lead (II) thiocyanate (Pb(SCN)2) precursor in preparing perovskite solar cells in ambient air. High-quality CH3NH3PbI3-x(SCN)x perovskite films can be readily prepared even when the relative humidity exceeds 70%. Under optimized processing conditions, we obtain devices with an average power conversion efficiency of 13.49% and the maximum efficiency over 15%. In comparison with typical CH3NH3PbI3-based devices, these solar cells without encapsulation show greatly improved stability in humid air, which is attributed to the incorporation of thiocyanate ions in the crystal lattice. The findings pave a way for realizing efficient and stable perovskite solar cells in ambient atmosphere.

  19. Investigations on the performance of a double pass, hybrid - type (PV/T) solar air heater

    Energy Technology Data Exchange (ETDEWEB)

    Srinivas, M.; Jayaraj, S. [Department of Mechanical Engineering, National Institute of Technology, Calicut-673601 (India)

    2013-07-01

    A solar hybrid energy system having photovoltaic and thermal (PV/T) devices, which produces both thermal and electrical energies simultaneously is considered for analysis. A double pass hybrid solar air (PV/T) heater with slats is designed and fabricated to study its thermal and electrical performance. Air as a heat removing fluid is made to flow through upper and lower channels of the collector. The collector is designed in such a way that the absorber plate is partially covered by solar cells. The raise in temperature of the solar cell is expected to decrease its electrical performance. Thin metallic strips called slats are attached longitudinally at the bottom side of the absorber plate to improve the system performance by increasing the cooling rate of the absorber plate. Thermal and electrical performances of the whole system at varying cooling conditions are presented. An artificial neural network model is used for forecasting the system performance at any desired conditions. The proposed model can be successfully used for evaluating the effect of different operating parameters under different ambient conditions for predicting the overall performance of the system.

  20. Impacts of Air Pollution on Solar Photovoltaic Electricity Generation in China

    Science.gov (United States)

    Li, X.; Mauzerall, D. L.; Wagner, F.; Yang, J.

    2015-12-01

    Solar photovoltaic (PV) electricity generation has been expanding rapidly in China with total capacity quadrupled from 8 to 32 GW between 2012 and 2014. Studies find that China has the potential to increase solar PV in total energy generation up towards 10% (about 300 GW in total capacity) by 2030. However, severe air pollution in China reduces the productivity of solar PV panels by scattering and absorbing sunlight before it reaches the surface. In this study, we first calculate the surface radiative forcing of anthropogenic aerosols (considering only the direct effect) over China from 2003 to 2013 using the Monitoring Atmospheric Composition and Climate (MACC) reanalysis dataset constrained by satellite derived greenhouse gas, reactive gases and aerosols. Our results indicate that, from 2003-2013, the attenuation of sunlight by aerosols over Eastern China averaged about -25 W m-2 compared with the global mean effect of -4.4 W m-2. The largest attenuation is found in Northern China in spring when mean attenuation reached as high as -57 W m-2. This attenuation reduced surface radiative flux by approximately 10%. In Southeastern China, maximum attenuation also occurred in spring, but had a smaller -40 W m-2 monthly mean. Western China is pristine in comparison, featuring no more than a -15 W m-2 monthly mean attenuation. These results imply a potentially large benefit for solar PV efficiency of improving air quality in eastern regions of China. We estimate that, if anthropogenic aerosols were entirely removed in China, solar PV generation would (1) increase 4.5-6.7% (varying among provinces) in Northeastern China where there is abundant solar resource,; (2) reduce the payback period by up to 1 year, increasing investment incentives particularly for distributed PV in Eastern China; and (3) increase total electricity generation in China in 2030 by up to 34 TWh/yr if the total capacity reaches 480 GW, equivalent to one-third of current annual electricity generation

  1. Numerical simulation and performance assessment of an absorption solar air-conditioning system coupled with an office building

    OpenAIRE

    Thomas, Sébastien; Andre, Philippe

    2010-01-01

    To minimize environmental impact and CO2 production associated with air-conditioning, it is reasonable to evaluate the prospects of a clean energy source. Solar energy, via thermal collectors can provide a part of the heating needs. Moreover, it can drive absorption chiller in order to satisfy the cooling needs of buildings. The objective of the work is to evaluate accurately the energy consumption of an air conditioning system including a solar driven absorption chiller. The c...

  2. Experimental Study of the Performance of Air Source Heat Pump Systems Assisted by Low-Temperature Solar-Heated Water

    OpenAIRE

    Jinshun Wu; Chao Chen; Song Pan; Jun Wei; Tianquan Pan; Yixuan Wei; Yunmo Wang; Xinru Wang; Jiale Su

    2013-01-01

    Due to the low temperatures, the heating efficiency of air source heat pump systems during the winter is very low. To address this problem, a low-temperature solar hot water system was added to a basic air source heat pump system. Several parameters were tested and analyzed. The heat collection efficiency of the solar collector was analyzed under low-temperature conditions. The factors that affect the performance of the heat pumps, such as the fluid temperature, pressure, and energy savings, ...

  3. Solar air-conditioning in buildings of houses; Climatizacion solar en edificios de viviendas

    Energy Technology Data Exchange (ETDEWEB)

    Rey, F. J.; Velasco, E.; Flores, F.; Gonzalez, A. B.

    2008-07-01

    In this work we analyze the behavior of the components of a thermal solar energy captation system that provides support to a climatization system with low energy consumption composed by radiating-refreshing ground in a single family dwelling. The combination of both system allows to increase the efficiency of the climatization and to reduce the energy domestic consumption. These aspects are included in regional an national strategies of saving and efficiency energy. tho this end, we shall use the software TRNSYS 16 for the energy systems simulation. (Author)

  4. Solar Absorption Refrigeration System for Air-Conditioning of a Classroom Building in Northern India

    Science.gov (United States)

    Agrawal, Tanmay; Varun; Kumar, Anoop

    2015-10-01

    Air-conditioning is a basic tool to provide human thermal comfort in a building space. The primary aim of the present work is to design an air-conditioning system based on vapour absorption cycle that utilizes a renewable energy source for its operation. The building under consideration is a classroom of dimensions 18.5 m × 13 m × 4.5 m located in Hamirpur district of Himachal Pradesh in India. For this purpose, cooling load of the building was calculated first by using cooling load temperature difference method to estimate cooling capacity of the air-conditioning system. Coefficient of performance of the refrigeration system was computed for various values of strong and weak solution concentration. In this work, a solar collector is also designed to provide required amount of heat energy by the absorption system. This heat energy is taken from solar energy which makes this system eco-friendly and sustainable. A computer program was written in MATLAB to calculate the design parameters. Results were obtained for various values of solution concentrations throughout the year. Cost analysis has also been carried out to compare absorption refrigeration system with conventional vapour compression cycle based air-conditioners.

  5. Exergetic and Thermoeconomic Analyses of Solar Air Heating Processes Using a Parabolic Trough Collector

    Directory of Open Access Journals (Sweden)

    Miguel Ángel Hernández-Román

    2014-08-01

    Full Text Available This paper presents a theoretical and practical analysis of the application of the thermoeconomic method. A furnace for heating air is evaluated using the methodology. The furnace works with solar energy, received from a parabolic trough collector and with electricity supplied by an electric power utility. The methodology evaluates the process by the first and second law of thermodynamics as the first step then the cost analysis is applied for getting the thermoeconomic cost. For this study, the climatic conditions of the city of Queretaro (Mexico are considered. Two periods were taken into account: from July 2006 to June 2007 and on 6 January 2011. The prototype, located at CICATA-IPN, Qro, was analyzed in two different scenarios i.e., with 100% of electricity and 100% of solar energy. The results showed that thermoeconomic costs for the heating process with electricity, inside the chamber, are less than those using solar heating. This may be ascribed to the high cost of the materials, fittings, and manufacturing of the solar equipment. Also, the influence of the mass flow, aperture area, length and diameter of the receiver of the solar prototype is a parameter for increasing the efficiency of the prototype in addition to the price of manufacturing. The optimum design parameters are: length is 3 to 5 m, mass flow rate is 0.03 kg/s, diameter of the receiver is around 10 to 30 mm and aperture area is 3 m2.

  6. Single and double pass solar air heaters with wire mesh as packing bed

    Energy Technology Data Exchange (ETDEWEB)

    Aldabbagh, L.B.Y.; Egelioglu, F. [Mechanical Engineering Department, Eastern Mediterranean University, Magosa, Mersin 10 (Turkey); Ilkan, M. [School of Computing and Tecnology, Eastern Mediterranean University, Magosa, Mersin 10 (Turkey)

    2010-09-15

    The thermal performances of single and double pass solar air heaters with steel wire mesh layers are used instead of a flat absorber plate are investigated experimentally. The effects of mass flow rate of air on the outlet temperature and thermal efficiency were studied. The results indicate that the efficiency increases with increasing the mass flow rate for the range of the flow rate used in this work between 0.012 and 0.038 kg/s. For the same flow rate, the efficiency of the double pass is found to be higher than the single pass by 34-45%. Moreover, the maximum efficiencies obtained for the single and the double pass air collectors are 45.93 and 83.65% respectively for the mass flow rate of 0.038 kg/s. Comparison of the results of a packed bed collector with those of a conventional collector shows a substantial enhancement in the thermal efficiency. (author)

  7. Performance study of solar air heater duct having absorber plate with V down perforated baffles

    Directory of Open Access Journals (Sweden)

    Sunil Chamoli

    2014-04-01

    Full Text Available This paper presents results of a study of the performance of solar air heaters with V down perforated baffles as roughness on the air flow side of the absorber plate. Investigations have been carried out using a mathematical model to study the effects of ambient conditions, operating and design parameters on effective efficiency of such air heaters. The thermal and effective efficiencies differ only marginally at lower flow rates. With an increase in the flow rate, the difference between the thermal and effective efficiencies increases because of the increase in the pumping power. The results of the study are presented in the form of plots to show the effect of ambient, design and operating conditions on thermal and effective efficiency.

  8. Experimental performance of single and double pass solar air heater with fins and steel wire mesh as absorber

    Energy Technology Data Exchange (ETDEWEB)

    Omojaro, A.P.; Aldabbagh, L.B.Y. [Mechanical Engineering Dept., Eastern Mediterranean University, Gazimagusa, Mersin 10 (Turkey)

    2010-12-15

    Thermal performance of a single and double pass solar air heater with fins attached and using a steel wire mesh as absorber plate was investigated experimentally. The effects of air mass flow rate range between 0.012 kg/s and 0.038 kg/s on the outlet temperature and thermal efficiency was studied. The bed heights were 7 cm and 3 cm for the lower and upper channels respectively. Result shows that, the efficiency increase with increasing air mass flow rate. For the same flow rate, the efficiency of the double pass is found to be higher than the single pass by 7-19.4%. Maximum efficiency obtained for the single and double pass air heater was 59.62% and 63.74% respectively for air mass flow rate of 0.038 kg/s. Moreover, the thermal efficiency further decreases by increasing the height of the first pass of the double pass solar air heater. The temperature difference between the outlet flow and the ambient, {delta}T, reduces as the air mass flow rate increase The result of a single or double solar air heater using steel wire mesh arrange in layers as an absorber plate and packing material when compared with a conventional solar air heater shows a much more substantial enhancement in the thermal efficiency. (author)

  9. Outdoor test for thermal performance evaluation of the Owens-Illinois Sunpack SEC-601 (air) solar collector

    Science.gov (United States)

    1979-01-01

    The test procedures used and the test results obtained during the performance of an evaluation test program on the Owens-Illinois Sunpak, model SEC-601, air solar collector under natural outdoor weather conditions are presented. All testing activities were performed on a single module. The test was performed and the data evaluated as applicable to outdoor testing of solar collectors.

  10. Exergetic performance assessment of a solar photovoltaic thermal (PV/T) air collector

    Energy Technology Data Exchange (ETDEWEB)

    Sarhaddi, F.; Farahat, S.; Ajam, H.; Behzadmehr, A. [Department of Mechanical Engineering, Shahid Nikbakht Faculty of Engineering, University of Sistan and Baluchestan, Zahedan 98164-161 (Iran, Islamic Republic of)

    2010-11-15

    In this paper, an attempt is made to evaluate the exergetic performance of a solar photovoltaic thermal (PV/T) air collector. A detailed energy and exergy analysis is carried out to calculate the thermal and electrical parameters, exergy components and exergy efficiency of a typical PV/T air collector. Some corrections are done on related heat loss coefficients. An improved electrical model is used to estimate the electrical parameters of a PV/T air collector. Further, a modified equation for the exergy efficiency of a PV/T air collector is derived in terms of design and climatic parameters. A computer simulation program is also developed to calculate the thermal and electrical parameters of a PV/T air collector. The results of numerical simulation are in good agreement with the experimental measurements noted in the previous literature. Finally, parametric studies have been carried out. It is observed that the modified exergy efficiency obtained in this paper is in good agreement with the one given by the previous literature. It is also found that the thermal efficiency, electrical efficiency, overall energy efficiency and exergy efficiency of PV/T air collector is about 17.18%, 10.01%, 45% and 10.75% respectively for a sample climatic, operating and design parameters. (author)

  11. Estudio regional del potencial de secado con aire natural y energía solar

    Directory of Open Access Journals (Sweden)

    Jorge Domínguez P.

    2011-11-01

    Full Text Available En este artículo se presenta y aplica una metodología de trabajo basada en la técnica de simulación matemática y desarrollada con el fin de realizar estudios sobre el potencial de secado de productos agropecuarios con aire natural y energía solar de regiones tropicales. La metodología se basa en el uso de un programa de computador e Incluye otros elementos metodológicos en relación con el manejo de la información meteorológica, el patrón de operación del ventilador, el uso de energía solar y la interpretación de los resultados con el fin de optimizar el sistema. Se reportan los resultados del estudio del potencial de secado con aire natural y energía solar de Tuluá (Valle y se proporcionan recomendaciones específicas para la implementación de sistemas de secado a bala temperatura en la Reglón.

  12. Prediction of Air Flow and Temperature Profiles Inside Convective Solar Dryer

    Directory of Open Access Journals (Sweden)

    Marian Vintilă

    2014-11-01

    Full Text Available Solar tray drying is an effective alternative for post-harvest processing of fruits and vegetables. Product quality and uniformity of the desired final moisture content are affected by the uneven air flow and temperature distribution inside the drying chamber. The purpose of this study is to numerically evaluate the operation parameters of a new indirect solar dryer having an appropriate design based on thermal uniformity inside the drying chamber, low construction costs and easy accessibility to resources needed for manufacture. The research was focused on both the investigation of different operation conditions and analysis of the influence of the damper position, which is incorporated into the chimney, on the internal cabinet temperature and air flow distribution. Numerical simulation was carried out with Comsol Multiphysics CFD commercial code using a reduced 2D domain model by neglecting any end effects from the side walls. The analysis of the coupled thermal-fluid model provided the velocity field, pressure distribution and temperature distribution in the solar collector and in the drying chamber when the damper was totally closed, half open and fully open and for different operation conditions. The predicted results were compared with measurements taken in-situ. With progressing computing power, it is conceivable that CFD will continue to provide explanations for more fluid flow, heat and mass transfer phenomena, leading to better equipment design and process control for the food industry.

  13. Solar energy contribution to the energy demand for air conditioning system in an office building under Tripoli climate conditions

    Directory of Open Access Journals (Sweden)

    Musbah Mohamed H.

    2014-01-01

    Full Text Available The feasibility of solar assisted air conditioning in an office building under Tripoli weather conditions is investigated in this paper. A single-effect lithium bromide absorption cycle powered by means of flat-plate solar collectors was modeled in order to predict the potential of the solar energy share. The cooling load profile was generated by using an detailed hourly based program and Typical meteorological year for Tripoli. System performance and solar energy fraction were calculated by varying two major parameters (collector’s slope angle and collector area. The maximum solar fraction of 48% was obtained by means of 1400 m2 of collector surface area. Analysis of results showed that, besides the collector surface area, the main factors affecting the solar fraction were the local weather conditions (intensity of incident solar radiation and the time of day when the plant was operated.

  14. SOLAR DRYING KINETICS OF DATE PALM FRUITS ASSUMING A STEP-WISE AIR TEMPERATURE CHANGE

    Directory of Open Access Journals (Sweden)

    ABDELGHANI BOUBEKRI

    2009-09-01

    Full Text Available The effect of drying using a step-wise temperature change was studied considering the case of indirect solar drying of the date palm fruit (Phoenix dactylifera L.. The followed procedure consists of building drying kinetics by stages of temperatures resulting from drying, in constant conditions, of the same variety of dates from Algerian and Tunisian origin. A law of daily temperature variation prevailed by 60°C, was deduced from a statement of temperature collected on a laboratory solar dryer prototype. Two drying curve equation models were used and some comparisons were discussed. The results obtained for dates from the two origins highlighted different response times by changing the air temperature and showed the possibility of reaching a fruit with standard moisture content in only one day of drying on the basis of initial water contents ranging from 0.40 to 0.65. This moisture range is in practice allotted to rehydrated dates by water immersion in order to enhance their quality. Experiments conducted in a laboratory solar drier under temperatures oscillating around 50°C and 60°C led to the same end up regarding the drying time ensuring a visually appreciable fruit quality. Results obtained by a simple sensorial test revealed a better quality of date fruits treated by solar drying comparing to those issued from industrial heat treatment units.

  15. CERIT air-conditioning system powered by solar energy: Two years of operation

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarin, R.; Romagnoni, P.; Casasola, L. (Bari Univ. (Italy). Ist. di Fisica Tecnica ed Impianti Termotecnici CERIT S.p.A., Pordenone (Italy) Padova Univ. (Italy). Ist. di Fisica Tecnica)

    The largest European solar air conditioner (equipped with 440 square meters of aluminized Myler reflection panels; 440 square meters of Cortec evacuated tube solar collectors; 150 and 43 cubic meter, respectively, cold and hot water storage tanks; 50 kW absorption machine; 4 cylinder compression chiller; and natural gas fired boiler for winter space heating) was built at the CERIT (Regional Technological Research Center) of Pordenone, Italy. This article, with the aid of flowsheets, outlines the plant's key design and operational features, and tables performance and energy consumption data to back up a discussion of the major results achieved during two years of operation. Particular attention is given to the plant's seasonal performance.

  16. Ozone changes under solar geoengineering: implications for UV exposure and air quality

    Science.gov (United States)

    Nowack, P. J.; Abraham, N. L.; Braesicke, P.; Pyle, J. A.

    2015-11-01

    Various forms of geoengineering have been proposed to counter anthropogenic climate change. Methods which aim to modify the Earth's energy balance by reducing insolation are often subsumed under the term Solar Radiation Management (SRM). Here, we present results of a standard SRM modelling experiment in which the incoming solar irradiance is reduced to offset the global mean warming induced by a quadrupling of atmospheric carbon dioxide. For the first time in an atmosphere-ocean coupled climate model, we include atmospheric composition feedbacks such as ozone changes under this scenario. Including the composition changes, we find large reductions in surface UV-B irradiance, with implications for vitamin D production, and increases in surface ozone concentrations, both of which could be important for human health. We highlight that both tropospheric and stratospheric ozone changes should be considered in the assessment of any SRM scheme, due to their important roles in regulating UV exposure and air quality.

  17. Ozone changes under solar geoengineering: implications for UV exposure and air quality

    Directory of Open Access Journals (Sweden)

    P. J. Nowack

    2015-11-01

    Full Text Available Various forms of geoengineering have been proposed to counter anthropogenic climate change. Methods which aim to modify the Earth's energy balance by reducing insolation are often subsumed under the term Solar Radiation Management (SRM. Here, we present results of a standard SRM modelling experiment in which the incoming solar irradiance is reduced to offset the global mean warming induced by a quadrupling of atmospheric carbon dioxide. For the first time in an atmosphere–ocean coupled climate model, we include atmospheric composition feedbacks such as ozone changes under this scenario. Including the composition changes, we find large reductions in surface UV-B irradiance, with implications for vitamin D production, and increases in surface ozone concentrations, both of which could be important for human health. We highlight that both tropospheric and stratospheric ozone changes should be considered in the assessment of any SRM scheme, due to their important roles in regulating UV exposure and air quality.

  18. Estudio regional del potencial de secado con aire natural y energía solar

    OpenAIRE

    Jorge Domínguez P.; Alfonso Parra C.; Luis Gabriel Villa

    2011-01-01

    En este artículo se presenta y aplica una metodología de trabajo basada en la técnica de simulación matemática y desarrollada con el fin de realizar estudios sobre el potencial de secado de productos agropecuarios con aire natural y energía solar de regiones tropicales. La metodología se basa en el uso de un programa de computador e Incluye otros elementos metodológicos en relación con el manejo de la información meteorológica, el patrón de operación del ventilador, el uso de energía solar y ...

  19. Thermal design of a modern, air-conditioned, single-floor, solar-powered desert house

    KAUST Repository

    Serag-Eldin, M. A.

    2011-12-01

    The paper presents a thermal analysis of a single-floor, solar-powered desert house. The house is air-conditioned and provides all modern comforts and facilities. Electrical power, which drives the entire energy system, is generated by roof-mounted photovoltaic modules. The modules are fixed on special cradles which fold at night to expose the roof to the night sky, thereby enhancing night-time cooling, which is substantial in the desert environment. A detailed dynamic heat transfer analysis is conducted for the building envelope, coupled with a solar radiation model. Application to a typical Middle-Eastern desert site reveals that indeed such a design is feasible with present-day technology; and should be even more attractive with future advances in technology. © 2011 Copyright Taylor and Francis Group, LLC.

  20. Influence of the atmospheric aerosol and air pollution on solar albedo of the earth. Vol. 4

    International Nuclear Information System (INIS)

    The effect of increasing atmospheric aerosol and air pollutant concentration on the solar albedo and consequently upon the heat budget near the earth's surface is studied. The magnitude of aerosol absorption coefficient to back-scattering coefficient Bab/Bbs is calculated. This study will be used to estimate atmospheric stability categories and other meteorological parameters which are affected by thermal state radiation balance of the atmosphere as mixing and inversion height of Inshas nuclear reactor site. Consequently, concentration distribution of radioactive release from Inshas can be evaluated.. 4 figs., 5 tabs

  1. Air Temperature estimation from Land Surface temperature and solar Radiation parameters

    Science.gov (United States)

    Lazzarini, Michele; Eissa, Yehia; Marpu, Prashanth; Ghedira, Hosni

    2013-04-01

    Air Temperature (AirT) is a fundamental parameter in a wide range of applications such as climate change studies, weather forecast, energy balance modeling, efficiency of Photovoltaic (PV) solar cells, etc. Air temperature data are generally obtained through regular measurements from meteorological stations. The distribution of these stations is normally sparse, so the spatial pattern of this parameter cannot be accurately estimated by interpolation methods. This work investigated the relationship between Air Temperature measured at meteorological stations and spatially contiguous measurements derived from Remote Sensing techniques, such as Land Surface Temperature (LST) maps, emissivity maps and shortwave radiation maps with the aim of creating a continuous map of AirT. For LST and emissivity, MSG-SEVIRI LST product from Land Surface Analysis Satellite Applications Facility (LSA-SAF) has been used. For shortwave radiation maps, an Artificial Neural Networks ensemble model has been developed and previously tested to create continuous maps from Global Horizontal Irradiance (GHI) point measurements, utilizing six thermal channels of MSG-SEVIRI. The testing sites corresponded to three meteorological stations located in the United Arab Emirates (UAE), where in situ measurements of Air Temperature were available. From the starting parameters, energy fluxes and net radiation have been calculated, in order to have information on the incoming and outgoing long-wave radiation and the incoming short-wave radiation. The preliminary analysis (day and Night measurements, cloud free) showed a strong negative correlation (0.92) between Outgoing long-wave radiation - GHI and LST- AirT, with a RMSE of 1.84 K in the AirT estimation from the initial parameters. Regression coefficients have been determined and tested on all the ground stations. The analysis also demonstrated the predominant impact of the incoming short-wave radiation in the AirT hourly variation, while the incoming

  2. Effect of selective coating on thermal performance of flat plate solar air heaters

    Energy Technology Data Exchange (ETDEWEB)

    El-Sebaii, A.A.; Al-Snani, H. [Physics Department, Faculty of Science, King Abdul Aziz University, P. O. Box 80203, Jeddah 21589 (Saudi Arabia)

    2010-04-15

    A transient mathematical model was presented for a single pass flat plate solar air heater. This model was based on an analytical solution of the energy balance equations for various elements of the heater. The flowing air temperature was assumed to vary only in the flow direction. The thermal performance of the heater was investigated by computer simulation using the climatic conditions of Jeddah (lat. 21 42' N, long. 39 11' E), Saudi Arabia. Effects of solar radiation intensity, mass flow rate of the flowing air (m{sub f}) and the length (L) and width (b) of the absorber plat on the flowing air outlet temperature (T{sub fo}) and the heater instantaneous ({eta}{sub inst}) and daily ({eta}{sub d}) efficiencies were studied. To improve the heater performance, effect of using absorber plates coated with various selective coating materials on the heater performance was also investigated. The best performance was achieved using nickel-tin as a selective coating material with a daily average of the instantaneous efficiency of 0.46. To validate the proposed mathematical model, the simulated results were compared with the measurements that had been performed for the heater with a black painted absorber plate under Tanta, lat. 30 47' N (Egypt), weather conditions. It was found that the proposed model is able to predict the T{sub fo} accurately with a daily average relative percentage error of 7.7%. It was also inferred that the annual average of {eta}{sub d} with a nickel-tin selectively coated absorber is higher than that with a black painted absorber by 29.23%. (author)

  3. Penambahan Urea sebagai Co-Substrat pada Sistem High Rate Algae Reactor (HRAR untuk Pengolahan Air Limbah Tercemar Minyak Solar

    Directory of Open Access Journals (Sweden)

    Ayu Syarifa Darwinastwantya

    2014-09-01

    Full Text Available Kebutuhan bahan bakar minyak di Indonesia semakin meningkat. Peningkatan tersebut mengakibatkan eksplorasi dan pengolahan secara berlebihan. Eksplorasi dan pengolahan berlebihan akan memberikan dampak buruk bagi lingkungan, yaitu limbah. Limbah minyak bumi biasanya langsung dibuang ke lingkungan yang dapat menyebakan pencemaran lingkungan, misalnya air. Pengolahan limbah menggunakan alga dapat digunakan sebagai pengolahan lanjutan tanpa menimbulkan polusi tambahan. Penelitian ini bertujuan untuk mengkaji pengaruh penambahan urea sebagai co-substrat terhadap kinerja High Rate Algae Reactor (HRAR dalam menurunkan kandungan minyak dalam air limbah minyak bumi. Variabel penelitian adalah konsentrasi minyak solar dalam air limbah dan konsentrasi urea yang digunakan. Konsentrasi minyak solar yang dipakai berasal penelitian pendahuluan sebesar 346 ppm dan 692 ppm untuk 18 L alga. Penelitian utama dilakukan dengan menambahkan 3 konsentrasi urea yang berbeda. Penelitian dilakukan selama 14 hari setiap dua hari sekali untuk semua parameter. Parameter yang digunakan dalam penelitian adalah kandungan Oil and Grease, Chemical Oxygen Demand (COD, klorofil a, Dissolved Oxygen (DO, pH, nitrogen-amonia, temperatur, dan Mixed Liquor Suspended Solid (MLSS. Dalam penelitian utama, menunjukkan bahwa sistem HRAR dapat mengolah air limbah mengandung minyak solar. Efisiensi penyisihan minyak solar paling optimal oleh sistem HRAR untuk variasi penambahan minyak solar 346 ppm adalah dengan penambahan urea 0,1 gr/L sebesar 83,33% sedangkan untuk variasi penambahan minyak solar 692 ppm menggunakan penambahan urea sebesar 0,3 gr/L sebesar 85,05%.

  4. Theoretical storage capacity for solar air pretreatment liquid collector/regenerator

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Donggen; Zhang, Xiaosong; Yin, Yonggao [School of Energy and Environment, Southeast University, Nanjing 210096 (China)

    2008-08-15

    A new liquid regeneration equipment - solar air pretreatment collector/regenerator for liquid desiccant cooling system is put forward in this paper, which is preferable to solution regeneration in hot and moist climate in South China. The equipment can achieve liquid regeneration in lower temperature. When the solution and the air are in ''match'' state in collector/regenerator, a match air to salt mass ratio ASMR* is found by theoretical study in which there is the largest theoretical storage capacity SC{sub max}. At T{sub r} = 60{sup o}C and X{sub in} 2.33 kg/kg, theoretical calculation discovers when Y{sub in} drops from 29 to 14 g/kg, the SC{sub max} increase 50% compared with ASMR{sup *} being around 26-27. After two new concepts of the effective solution proportion (EPS) and the effective storage capacity (ESC) are defined, it is found by theoretical calculation that when ESP drops from 100% to 67%, ESC raises lowly, not drops and liquid outlet concentration C{sub str.sol} increases from 40% to 49% in which its increment totals to 90%. All these data explain fully that air pretreatment liquid regeneration equipment enables to improve the performance of liquid desiccant cooling system. (author)

  5. Performances of packed bed double pass solar air heater with different inclinations and transverse wire mesh with different intervals

    Directory of Open Access Journals (Sweden)

    Sugantharaj Gnanadurai Sam Stanley

    2016-01-01

    Full Text Available Solar air heating is a technology in which the solar energy from the sun is captured by an absorbing medium and used to heat the air flowing through the heater. In this study, thermal performance of a double pass solar air heater has been investigated experimentally at different conditions. The experiments were conducted with different inclinations of the collector, with and without wire mesh vertically fixed at the second pass in transverse direction and with different mass flow rates. The effect of air mass flow rate, wire mesh pitch and collector inclination on temperature rise and thermal efficiency have been studied. Results show that efficiency increases with mass flow rate. For the same mass flow rate, the thermal efficiency increases with the decrease in the wire mesh pitch. The maximum daily average efficiency of air heater was 79.8% at 0.025 kg/s mass flow rate, 10 cm wire mesh gap and 9º collector inclination facing south. The highest collector efficiency was observed in solar air heaters with 10 cm wire mesh gap.

  6. Experimental investigation on the photovoltaic-thermal solar heat pump air-conditioning system on water-heating mode

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Guiyin; Hu, Hainan; Liu, Xu [Department of Physics, Nanjing University, Nanjing 210093 (China)

    2010-09-15

    An experimental study on operation performance of photovoltaic-thermal solar heat pump air-conditioning system was conducted in this paper. The experimental system of photovoltaic-thermal solar heat pump air-conditioning system was set up. The performance parameters such as the evaporation pressure, the condensation pressure and the coefficient of performance (COP) of heat pump air-conditioning system, the water temperature and receiving heat capacity in water heater, the photovoltaic (PV) module temperature and the photovoltaic efficiency were investigated. The experimental results show that the mean photovoltaic efficiency of photovoltaic-thermal (PV/T) solar heat pump air-conditioning system reaches 10.4%, and can improve 23.8% in comparison with that of the conventional photovoltaic module, the mean COP of heat pump air-conditioning system may attain 2.88 and the water temperature in water heater can increase to 42 C. These results indicate that the photovoltaic-thermal solar heat pump air-conditioning system has better performances and can stably work. (author)

  7. Energy use test facility: CAC-DOE solar air heater test report

    Science.gov (United States)

    1981-11-01

    The solar air heater testing demonstrated an attractive application for residential space heating, especially appealing to the do-it-yourself market. Simple improvements in construction, such as caulking of the glazing, could increase collector performance at little cost. The operating cost of the fan was insignificant, being less than $0.05/week. Tested in its as-shipped configuration at 96.1 cfm (3 cfm/ft (2)), the useful energy delivered averaged 20,000 Btu/day for six days in December. The electrical consumption of the fan was approximately 1 kWh. Doubling the flowrate did not increase collector performance appreciably. A TRNSYS computer simulation model for this solar air heater design was validated by comparing the measured test data on Jaunary 4, 1981 with calculated values. TRNSYS predicted that measured collector outlet temperatures within +- 1.20F and the energy delivered within +- 3%. The excellent agreement was obtained by adjusting the collector loss coefficient to an unrealistically low value; therefore, a parametric study is recommended to determine the model sensitivity to varying different parameters. A first-order collector efficiency curve was derived from the TRNSYS simulations which compared well with the curve defined by the clear-day measured data.

  8. Characterization of Air-Based Photovoltaic Thermal Panels with Bifacial Solar Cells

    Directory of Open Access Journals (Sweden)

    P. Ooshaksaraei

    2013-01-01

    Full Text Available Photovoltaic (PV panels account for a majority of the cost of photovoltaic thermal (PVT panels. Bifacial silicon solar panels are attractive for PVT panels because of their potential to enhance electrical power generation from the same silicon wafer compared with conventional monofacial solar panels. This paper examines the performance of air-based bifacial PVT panels with regard to the first and second laws of thermodynamics. Four air-based bifacial PVT panels were designed. The maximum efficiencies of 45% to 63% were observed for the double-path-parallel bifacial PVT panel based on the first law of thermodynamics. Single-path bifacial PVT panel represents the highest exergy efficiency (10%. Double-path-parallel bifacial PVT panel is the second preferred design as it generates up to 20% additional total energy compared with the single-path panel. However, the daily average exergy efficiency of a double-path-parallel panel is 0.35% lower than that of a single-path panel.

  9. Heat flux: thermohydraulic investigation of solar air heaters used in agro-industrial applications

    Science.gov (United States)

    Rahmati Aidinlou, H.; Nikbakht, A. M.

    2016-07-01

    A new design of solar air heater simulator is presented to comply with the extensive applications inagro-industry. A wise installation of increased heat transfer surface area provided uniform and efficient heat diffusion over the duct. Nusselt number and friction factor have been investigated based on the constant roughness parameters such as relative roughness height (e/D), relative roughness pitch (P/e), angle of attack (α) and aspect ratio with Reynolds numbers ranging from 5000 to 19,000 in the fully developed region. Heat fluxes of 800, 900 and 1000 Wm-2 were provided. The enhancement in friction factor is observed to be 3.1656, 3.47 and 3.0856 times, and for the Nusselt number either, augmentation is calculated to be 1.4437, 1.4963 and 1.535 times, respectively, over the smooth duct for 800, 900 and 1000 Wm-2 heat fluxes. Thermohydraulic performance is plotted versus the Reynolds number based on the aforementioned roughness parameters at varying heat fluxes. The results show up that thermohydraulic performance is found to be maximum for 1000 Wm-2 at the average Reynolds number of 5151. Based on the results, we can verify that the introduced solar simulator can help analyzing and developing solar collector installations at the simulated heat fluxes.

  10. A Neural Network Based Intelligent Predictive Sensor for Cloudiness, Solar Radiation and Air Temperature

    Directory of Open Access Journals (Sweden)

    Pedro M. Ferreira

    2012-11-01

    Full Text Available Accurate measurements of global solar radiation and atmospheric temperature,as well as the availability of the predictions of their evolution over time, are importantfor different areas of applications, such as agriculture, renewable energy and energymanagement, or thermal comfort in buildings. For this reason, an intelligent, light-weightand portable sensor was developed, using artificial neural network models as the time-seriespredictor mechanisms. These have been identified with the aid of a procedure based on themulti-objective genetic algorithm. As cloudiness is the most significant factor affecting thesolar radiation reaching a particular location on the Earth surface, it has great impact on theperformance of predictive solar radiation models for that location. This work also representsone step towards the improvement of such models by using ground-to-sky hemisphericalcolour digital images as a means to estimate cloudiness by the fraction of visible skycorresponding to clouds and to clear sky. The implementation of predictive models inthe prototype has been validated and the system is able to function reliably, providingmeasurements and four-hour forecasts of cloudiness, solar radiation and air temperature.

  11. Thermal performance of solar air collector with transparent honeycomb made of glass tube

    Institute of Scientific and Technical Information of China (English)

    ZHANG ZhiQiang; ZUO Ran; LI Ping; SU WenJia

    2009-01-01

    Transparent honeycomb structure with thin-walled glass tube as the honeycomb unit is designed and applied to a flat-plate solar air collector.Experiments are performed for solar collectors with six different honeycomb sizes.The emphasis is to study the effects of diameter and aspect ratio of the honeycomb unit on the transmittance and efficiency of the solar collector.It is shown that for the same diameter but different aspect ratios,there are large temperature differences between the collector's exits;the smaller the aspect ratio,the larger the exit temperature,with a maximum difference of 10℃;for the same aspect ratio but different diameters,the temperature differences are small;the maximum temperature difference between the collectors with and without honeycombs is 12℃.A theoretical expression for the honeycomb transmittance is derived with a simplified method.The result shows that the honeycomb transmittance is only related with the aspect ratio and the materials' optical properties but not the actual size of the honeycomb.

  12. Thermal performance of solar air collector with transparent honeycomb made of glass tube

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Transparent honeycomb structure with thin-walled glass tube as the honeycomb unit is designed and applied to a flat-plate solar air collector. Experiments are performed for solar collectors with six different honeycomb sizes. The emphasis is to study the effects of diameter and aspect ratio of the honeycomb unit on the transmittance and efficiency of the solar collector. It is shown that for the same diameter but different aspect ratios, there are large temperature differences between the collector’s exits; the smaller the aspect ratio, the larger the exit temperature, with a maximum difference of 10℃; for the same aspect ratio but different diameters, the temperature differences are small; the maximum temperature difference between the collectors with and without honeycombs is 12℃. A theoretical expression for the honeycomb transmittance is derived with a simplified method. The result shows that the honeycomb transmittance is only related with the aspect ratio and the materials’ optical properties but not the actual size of the honeycomb.

  13. A comprehensive optical characterization of a porous open volumetric air receiver in a solar power tower

    CERN Document Server

    Qiu, Yu; He, Ya-Ling; Cheng, Ze-Dong

    2016-01-01

    A comprehensive optical model for a solar power tower with an open volumetric air receiver (OVAR) was developed and validated in this work. Based on the model, the optical characteristics of the OVAR were studied. Firstly, the detailed distributions of the non-uniform solar flux (qsr) on the aperture and the solar source (Ssr) in the OVAR were studied. The incident flux was found to be relatively uniform across the aperture for a single OVAR. However the incident angle of the rays varies between 0o and 42o, which indicates that the parallel assumption of the rays is not appropriate at this condition. Furthermore, the Ssr in the absorber decreases from the inlet to the outlet, and the maximum source (Ssr,max) of 2.414X108 Wm-3 appears at the inlet. Moreover, the Ssr,max was found to appear at the region near the wall rather than the center of the receiver as usual for the combined effect of the non-parallel incident rays and the diffuse reflection on the wall. The revelation of this phenomenon could offer help...

  14. Exergetic Optimization of Solar Air Heaters and Comparison with Energy Analysis

    Directory of Open Access Journals (Sweden)

    Saeid Farahat

    2005-12-01

    Full Text Available In this paper, an exergetic optimization of the solar air heater is developed. For this means, an integrated mathematical model of thermal and optical performance of the solar heater is derived. The most geometric parameters and operation conditions are considered as variables in this analysis. Some correlations for exergy efficiency of heater components are obtained. Then, exergy efficiency of the heater is derived by using these correlations. In the process of deriving an equation for the exergy efficiency, while the overall thermal loss coefficient and other heat transfer coefficients of the heater are assumed to be variable, the common error of using the Petela efficiency is corrected to reach the improved equation of solar radiation exergy. Finally, through the MATLAB toolbox the exergy efficiency equation is maximized. Then exergy efficiency is compared with the thermal efficiency of the heater, resulting in an extraordinary increase of the exergy efficiency according to the optimized parameters and benefit of this approach for such systems.

  15. IEA SHC Task 38 'Solar air-conditioning and refrigeration'. Danish participation 2007-2010. Appendix; IEA SHC Task 38 'Solar air-conditioning and refrigeration'. Dansk deltagelse 2007-2010. Bilag

    Energy Technology Data Exchange (ETDEWEB)

    Ellehauge, K. (Ellehauge og Kildemoes, Aarhus (Denmark)); Muenster, E. (PlanEnergi, Skoerping (Denmark)); Reinholdt, L. (Teknologisk Institut, Aarhus (Denmark)); Munds, S. (AC-Sun Aps, Horsens (Denmark))

    2011-03-15

    IEA SHC Task 38 'Solar Air-Conditioning and Refrigeration' ran from October 2006 to December 2010. Denmark was represented in the task from January 2007 to December 2010. The aim of the task was to encourage use of solar powered refrigeration and air conditioning systems in particular at residential, commercial and industrial sectors. Furthermore, the aim was to contribute to new research and development activities on new systems and concepts. The appendix contains the publications prepared by the Danish project group.(LN)

  16. Device Performance Improvement of Double-Pass Wire Mesh Packed Solar Air Heaters under Recycling Operation Conditions

    Directory of Open Access Journals (Sweden)

    Chii-Dong Ho

    2016-01-01

    Full Text Available The improvement of device performance of a recycling solar air heater featuring a wire mesh packing was investigated experimentally and theoretically. The application of the wire mesh packing and recycle-effect concept to the present study were proposed aiming to strengthen the convective heat-transfer coefficient due to increased turbulence. Comparisons were made among different designs, including the single-pass, flat-plate double-pass and recycling double-pass wire mesh packed operations. The collector efficiency of the recycling double-pass wire mesh packed solar air heater was much higher than that of the other configurations for various recycle ratios and mass flow rates scenarios. The power consumption increment due to implementing wire mesh in solar air heaters was also discussed considering the economic feasibility. A fairly good agreement between theoretical predictions and experimental measurements was achieved with an analyzed error of 1.07%–9.32%.

  17. Construction test modules to reduce the air conditioning consumption; Modulos de prueba de edificaciones para reducir el consumo de aire acondicionado

    Energy Technology Data Exchange (ETDEWEB)

    Acoltzi, Higinio [Instituto de Investigaciones Electricas, (Mexico); Alvarez, Gabriela [CENIDET (Mexico)

    2002-09-01

    In this work a mathematical model of the energy behavior of test modules to scale and its experimental verification is presented. The model determines the electrical energy consumption history, necessary to maintain the comfort conditions in the interior of the modules, with respect to the variation of the materials of the ceilings and windows, to establish the application criteria of these materials in the construction industry. Also are presented the measured results of energy consumption accumulated for the modules with ceilings, of monolithic slab as well as of joist and small arches, with wooden window frames and reflectasol filtrasol and clear glasses. [Spanish] En este trabajo se presenta un modelo matematico del comportamiento energetico de modulos de prueba a escala y su verificacion experimental. El modelo determina la historia del consumo de energia electrica, necesario para mantener las condiciones de confort al interior de los modulos, con respecto a la variacion de los materiales de los techos y ventanas, para establecer criterios de aplicacion de dichos materiales en la industria de la construccion. Tambien se presenta los resultados medidos del consumo de energia acumulada para los modulos con techos, tanto de losa monolitica como de vigueta y bovedilla, con ventanas de marco de madera y vidrios reflectasol, filtrasol y claro.

  18. Appraising the performance of a baffled solar air heater with external recycle

    International Nuclear Information System (INIS)

    Highlights: • Thermal performance for a baffled solar air heater with external recycle is studied. • Applying external recycle boosts the energy efficiency of the air heater remarkably. • Applying fins and baffles under external recycle enhances energy efficiency. • Utilizing baffles at high recycle ratios and mass flow rates declines ηeff. • Utilizing only fins at high mass flow rates and recycle ratios is well-organized. - Abstract: This study aims at appraising the possibility of enhancing thermal performance of an upward-type single pass solar air heater by utilizing fins and baffles over the absorber plate as well as applying external recycle device simultaneously under various parametric conditions. The energy and effective efficiencies analysis is used as criteria to evaluate the performance. The investigation is carried out for three cases: simple absorber plate, absorber plate with fins and absorber plate with fins and baffles. The achieved results disclose that attaching both fins and baffles to the absorber plate under external recycling operation is an effective method to boost the energy efficiency notably. In contrast, the effective efficiency analysis reveals that attaching both fins and baffles at high mass flow rates and recycle ratios leads to considerable decline in effective efficiency. Parametric studies on variation of baffle parameters illustrate that increasing the baffles width as well as declining the distance between baffles under turbulent flow regime are not economically feasible owing to extremely increase of the pressure drop and required pump work. In a nutshell, it is found that utilizing only fins under external recycle application at high mass flow rates and recycle ratios is an attractive option

  19. Numerical simulation of effective efficiency of a discrete multi V-pattern rib solar air channel

    Science.gov (United States)

    Kumar, Anil; Saini, R. P.; Saini, J. S.

    2016-10-01

    The use of artificial roughness in the form of repeated ribs has been found to be an efficient method of improving the heat transfer to fluid flowing in the channel. In this study, performance of solar air channel as a function of discrete multi V-pattern rib shapes has been investigated. The e/D was varied from 0.022 to 0.043, Gd/Lv was varied from 0.24 to 0.80, g/e was varied from 0.5 to 1.5, α was varied from 30° to 75°, P/e was varied from 6.0 to 12.0 and W/w was varied from 1.0 to 10.0. A methodology has been developed for the prediction of effective efficiency. Based on the values of effective efficiency, an optimization has been carried out to determine the set of data of roughness shapes parameters that correspond to better effective efficiency for given values of operating parameters of the air channel. Design plots have been represent to depict the data of individual roughness shapes parameters that characterize the optimum condition as a function of performance parameter and intensity of radiation. It was observed that the maximum values of effective efficiency for e/D of 0.043, Gd/Lv of 0.69, g/e of 1.0, α of 60°, P/e of 8.0 and W/w of 6.0. Discrete multi v-rib shape has been found to be better thermohydraulic performance (effective efficiency) as comparison to other rib shapes solar air channels.

  20. Performance evaluation of solar air heaters having v-down discrete rib roughness on the absorber plate

    Energy Technology Data Exchange (ETDEWEB)

    Karwa, Rajendra; Chauhan, Kalpana [Department of Mechanical Engineering, Faculty of Engineering and Architecture, Jai Narain Vyas University, Jodhpur 342 011 (India)

    2010-01-15

    This paper presents results of a study of the performance of solar air heaters with 60 v-down discrete rectangular cross-section repeated rib roughness on the air flow side of the absorber plate. A detailed investigation has been carried out using a mathematical model to study the effects of various ambient, operating and design parameters on the thermal efficiency and effective efficiency (based on the net gain after taking account of the pumping power) of such air heaters. The study shows that, at air mass flow rates less than about 0.04 kg s{sup -1} per m{sup 2} of the absorber plate, roughened duct solar air heaters provide significant performance advantage over the smooth duct air heater. The thermal and effective efficiencies differ only marginally at low flow rates. With the increase in the flow rate, the difference between the thermal and effective efficiencies increases because of the increase in the pumping power. At the mass flow rate of about 0.045 kg s{sup -1} m{sup -2}, the effective efficiencies of the roughened and smooth duct solar air heaters are practically the same. The results of the study are presented in the form of design plots. (author)

  1. Performance Analysis and Parametric Study of a Natural Convection Solar Air Heater With In-built Oil Storage

    Science.gov (United States)

    Dhote, Yogesh; Thombre, Shashikant

    2016-05-01

    This paper presents the thermal performance of the proposed double flow natural convection solar air heater with in-built liquid (oil) sensible heat storage. Unused engine oil was used as thermal energy storage medium due to its good heat retaining capacity even at high temperatures without evaporation. The performance evaluation was carried out for a day of the month March for the climatic conditions of Nagpur (India). A self reliant computational model was developed using computational tool as C++. The program developed was self reliant and compute the performance parameters for any day of the year and would be used for major cities in India. The effect of change in storage oil quantity and the inclination (tilt angle) on the overall efficiency of the solar air heater was studied. The performance was tested initially at different storage oil quantities as 25, 50, 75 and 100 l for a plate spacing of 0.04 m with an inclination of 36o. It has been found that the solar air heater gives the best performance at a storage oil quantity of 50 l. The performance of the proposed solar air heater is further tested for various combinations of storage oil quantity (50, 75 and 100 l) and the inclination (0o, 15o, 30o, 45o, 60o, 75o, 90o). It has been found that the proposed solar air heater with in-built oil storage shows its best performance for the combination of 50 l storage oil quantity and 60o inclination. Finally the results of the parametric study was also presented in the form of graphs carried out for a fixed storage oil quantity of 25 l, plate spacing of 0.03 m and at an inclination of 36o to study the behaviour of various heat transfer and fluid flow parameters of the solar air heater.

  2. The air quality and regional climate effects of widespread solar power generation under a changing regulatory environment

    Science.gov (United States)

    Millstein, D.; Zhai, P.; Menon, S.

    2011-12-01

    Over the past decade significant reductions of NOx and SOx emissions from coal burning power plants in the U.S. have been achieved due to regulatory action and substitution of new generation towards natural gas and wind power. Low natural gas prices, ever decreasing solar generation costs, and proposed regulatory changes, such as to the Cross State Air Pollution Rule, promise further long-run coal power plant emission reductions. Reduced power plant emissions have the potential to affect ozone and particulate air quality and influence regional climate through aerosol cloud interactions and visibility effects. Here we investigate, on a national scale, the effects on future (~2030) air quality and regional climate of power plant emission regulations in contrast to and combination with policies designed to aggressively promote solar electricity generation. A sophisticated, economic and engineering based, hourly power generation dispatch model is developed to explore the integration of significant solar generation resources (>10% on an energy basis) at various regions across the county, providing detailed estimates of substitution of solar generation for fossil fuel generation resources. Future air pollutant emissions from all sectors of the economy are scaled based on the U.S. Environmental Protection Agency's National Emission Inventory to account for activity changes based on population and economic projections derived from county level U.S. Census data and the Energy Information Administration's Annual Energy Outlook. Further adjustments are made for technological and regulatory changes applicable within various sectors, for example, emission intensity adjustments to on-road diesel trucking due to exhaust treatment and improved engine design. The future year 2030 is selected for the emissions scenarios to allow for the development of significant solar generation resources. A regional climate and air quality model (Weather Research and Forecasting, WRF model) is

  3. Numerical study on optical and electric-thermal performance for solar concentrating PV/T air system

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Hybrid photovoltaic/thermal(PV/T)system with solar concentrator is an effective way to improve solar energy conversion efficiency.In this work,a single-pass PV/T air system with a three-trough compound parabolic concentrator(CPC)of concentration ratio 2.0 is designed and the solar incident distributions at the solar cell surface are calculated by ray tracing method.Based on energy balance,the heat transfer models of all main components in this system are developed.The effects of some main designing and operational parameters on the electric-thermal performance of the system are analyzed. The results show that the solar radiation intensity can be higher than 1200 W/m 2 at most area of the cell surface.The temperature of the air and cell surface increases along the length of the system.Thus the system efficiency of the CPC is higher than that of the system without the CPC.The thermal efficiency, exergy and electrical efficiency of this CPC system increase with increasing of the air mass flow rate and the length of the system.With increasing packing fraction the electrical efficiency increases,but the thermal efficiency decreases.The exergy efficiency increases slightly with the packing fraction rising.The data obtained in this work are valuable for the design and operation for this kind of solar concentrating PV/T systems.

  4. Development of Mobile Solar Evaluation Laboratory & Technical and Economic Performance of the Goldade Site-Built Air Collector

    Science.gov (United States)

    Goldade, Travis D.

    The Great Basin climate type is ideal for the utilization of solar winter space heat from air collectors; perhaps the most economically viable option for solar space heating is that of site built air collectors (SBAC). Unfortunately SBACs are a rarely utilized technology primarily because there is presently no standard method to test these types of collectors. This thesis provides a viable testing method for SBACs and the theoretical calculations required to develop testing and provide ratings based on industry standards. This leads to development of the Mobile Solar Evaluation Laboratory (MSEL). The Goldade Family built a 128 ft2 solar air heater for winter space heating, and the MSEL was employed to evaluate the technical and economic performance of that system. Theory and field testing correlated well, and it was proven that the MSEL accurately predicts SBAC performance. In most Northern Nevada households solar space heating can be cost effective. Solar space heating also reduces substantial CO2 from being added to the atmosphere.

  5. Impact of Aspect Ratio and Solar Heating on Street Conyn Air Temperature

    Directory of Open Access Journals (Sweden)

    Rizwan Ahmed Memon

    2011-01-01

    Full Text Available The results obtained from RNG (Re-Normalization Group version of k-? turbulence model are reported in this study. The model is adopted to elucidate the impact of different building aspect ratios (i.e., ratio of building-height-to-street-canyon-width and solar heating on temperatures in street canyon. The validation of Navier-Stokes and energy transport equations showed that the model prediction for air-temperature and ambient wind provides reasonable accuracy. The model was applied on AR (Aspect Ratios one to eight and surface temperature difference (??s-a of 2 -8. Notably, air-temperatures were higher in high AR street canyons in particular on the leeward side of the street canyon. Further investigation showed that the difference between the air-temperature of high and low AR street canyons ( AR was positive and high with higher ??s-a. Conversely, the AR become negative and low gradually with lower values of ??s-a. These results could be very beneficial for the city and regional planners, civil engineers and HVAC experts who design street canyons and strive for human thermal comfort with minimum possible energy requirements.

  6. Impact of aspect ratio and solar heating on street canyon air temperature

    International Nuclear Information System (INIS)

    The results obtained from RNG (Re-Normalization Group) version of k-and turbulence model are reported in this study. The model is adopted to elucidate the impact of different building aspect ratios (i.e., ratio of building-height-to-street-canyon-width) and solar heating on temperatures in street canyon. The validation of Navier-Stokes and energy an sport equations showed that the model prediction for air-temperature and ambient wind provides reasonable accuracy. The model was applied on AR (Aspect Ratios) one to eight and surface temperature difference (delta and theta/sub s-a/)) of 2 -8. Notably, air-temperatures were higher in high AR street canyons in particular on the leeward side of the street canyon. Further investigation showed that the difference between the air-temperature 'high and low AR street canyons (AR) was positive and high with higher delta and theta/sub s-a/) conversely, the AR become negative and low gradually with lower values of delta and theta(/sub s-a/). These results could be very beneficial for the city and regional planners, civil engineers Id HVAC experts who design street canyons and strive for human thermal comfort with minimum possible energy requirements. (author)

  7. Experimental investigation of thermal performance of a double-flow solar air heater having aluminium cans

    Energy Technology Data Exchange (ETDEWEB)

    Ozgen, Filiz; Esen, Mehmet; Esen, Hikmet [Department of Mechanical Education, Faculty of Technical Education, Firat University, 23119 Elazig (Turkey)

    2009-11-15

    This study experimentally investigates a device for inserting an absorbing plate made of aluminium cans into the double-pass channel in a flat-plate solar air heater (SAH). This method substantially improves the collector efficiency by increasing the fluid velocity and enhancing the heat-transfer coefficient between the absorber plate and air. These types of collectors had been designed as a proposal to use aluminium materials to build absorber plates of SAHs at a suitable cost. The collector had been covered with a 4-mm single glass plate, in order to reduce convective loses to the atmosphere. Three different absorber plates had been designed and tested for experimental study. In the first type (Type I), cans had been staggered as zigzag on absorber plate, while in Type II they were arranged in order. Type III is a flat plate (without cans). Experiments had been performed for air mass flow rates of 0.03 kg/s and 0.05 kg/s. The highest efficiency had been obtained for Type I at 0.05 kg/s. Also, comparison between the thermal efficiency of the SAH tested in this study with the ones reported in the literature had been presented, and a good agreement had been found. (author)

  8. Experimental study of the influence of collector height on the steady state performance of a passive solar air heater

    Energy Technology Data Exchange (ETDEWEB)

    Ryan, D.; Burek, S.A.M. [School of the Built and Natural Environment, Glasgow Caledonian University, Cowcaddens Road, Glasgow, G4 0BA Scotland (United Kingdom)

    2010-09-15

    Passive solar air heaters, such as solar chimneys and Trombe Walls, rely on solar-induced buoyancy-driven (natural) convection to produce the flow of air. Although buoyancy-driven convection is well understood for a single vertical plate, buoyancy-driven convection in an asymmetrically-heated channel is more problematic, and in particular, the effects of the channel height on the flow rate and heat transfer. This paper reports on experiments on test rigs resembling lightweight passive solar air-heating collectors. The test rigs were of heights 0.5, 1.0 and 2.0 m, with adjustable channel depths (20-150 mm) and heat inputs (up to 1000 W/m{sup 2}). Measurements were made of the air, plate and cover temperatures, and air velocities. Results are presented as dimensionless correlations of mass flow (as Reynolds number) and efficiency against heat input (as Rayleigh number), channel depth and height. Thermal efficiency is shown to be a function of the heat input and the system height, but not of the channel depth; mass flow is shown to be a dependent on all three parameters. (author)

  9. Effect of external recycle on the performances of flat-plate solar air heaters with internal fins attached

    Energy Technology Data Exchange (ETDEWEB)

    Yeh, Ho-Ming; Ho, Chii-Dong [Energy and Opto-Electronic Materials Research Center, Department of Chemical and Materials Engineering, Tamkang University, 151 Ying-Chuan Road, Tamsui, Taipei County 25137 (China)

    2009-05-15

    The influence of external recycle on the collector efficiency in solar air heaters with internal fins attached, has been investigated theoretically. The application of external recycle operation to solar air heaters actually has two conflict effects. One is the increase in fluid velocity to decrease the heat-transfer resistance, which is good for performance, while the other is lowering the driving force (temperature difference) of heat-transfer, due to the remixing at the inlet, which is bad for performance. It is found that considerable improvement in collector efficiency is obtainable if the operation is carried out with an external recycle, where the desirable effect overcomes the undesirable effect. The enhancement increases with increasing reflux ratio, especially for operating at lower air flow rate with higher inlet air temperature. (author)

  10. An experimental investigation of performance of a double pass solar air heater with thermal storage medium

    Directory of Open Access Journals (Sweden)

    Ali Hafiz Muhammad

    2015-01-01

    Full Text Available The performance of a double pass solar air heater was experimentally investigated using four different configurations. First configuration contained only absorber plate whereas copper tubes filled with thermal storage medium (paraffin wax were added on the absorber plate in the second configuration. Aluminum and steel rods as thermal enhancer were inserted in the middle of paraffin wax of each tube for configurations three and four respectively. Second configuration provided useful heat for about 1.5 hours after the sunset compared to first configuration. Configurations three and four provided useful heat for about 2 hours after the sunset. The maximum efficiency of about 96% was achieved using configuration three (i.e. using Aluminum rods in the middle of copper tubes filled with paraffin wax.

  11. The new solar energy air conditioning system of CERIT (Pordenone, Italy). First experimental results

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarin, R.; Casasola, L. (Bari Univ. (Italy). Ist. di Fisica Tecnica ed Impianti Termotecnici; CERIT SpA, Pordenone (Italy))

    For air conditioning in the CERIT (Regional Center for Technological Research) building of Pordenone (Italy), a solar plant was installed, with a surface area of 430 square meters of evacuated-tube collectors, a reflecting surface of the same area, and an absorption refrigerating system. Furthermore, this plant was equipped with a 43 cubic meter heat storage unit at the temperature of 80-90 degrees C and also a 150 cubic meter cold storage unit. The choice of the collectors was made after a series of tests on various models existing on the market. A careful calculation was carried out on the advantages of flat reflectors. An estimate, reflecting results after one year of operation, of the plant's performance was developed.

  12. Air shower simulation for WASAVIES: warning system for aviation exposure to solar energetic particles.

    Science.gov (United States)

    Sato, T; Kataoka, R; Yasuda, H; Yashiro, S; Kuwabara, T; Shiota, D; Kubo, Y

    2014-10-01

    WASAVIES, a warning system for aviation exposure to solar energetic particles (SEPs), is under development by collaboration between several institutes in Japan and the USA. It is designed to deterministically forecast the SEP fluxes incident on the atmosphere within 6 h after flare onset using the latest space weather research. To immediately estimate the aircrew doses from the obtained SEP fluxes, the response functions of the particle fluxes generated by the incidence of monoenergetic protons into the atmosphere were developed by performing air shower simulations using the Particle and Heavy Ion Transport code system. The accuracy of the simulation was well verified by calculating the increase count rates of a neutron monitor during a ground-level enhancement, combining the response function with the SEP fluxes measured by the PAMELA spectrometer. The response function will be implemented in WASAVIES and used to protect aircrews from additional SEP exposure.

  13. Collector Efficiency in Downward-Type Internal-Recycle Solar Air Heaters with Attached Fins

    Directory of Open Access Journals (Sweden)

    Chii-Dong Ho

    2013-10-01

    Full Text Available The internal-recycle operation effect on collector efficiency in downward-type rectangular solar air heaters with attached fins is theoretically investigated. It is found that considerable collector efficiency is obtainable if the collector has attached fins and the operation is carried out with internal recycling. The recycling operation increases the fluid velocity to decrease the heat transfer resistance, compensating for the undesirable effect of decreasing the heat transfer driving force (temperature difference due to remixing. The attached fins provide an enlarged heat transfer area. The order of performance in a device of same size is: double pass with recycle and fins > double pass with recycle but without fins > single pass without recycle and fins.

  14. Stratospheric ozone changes under solar geoengineering: implications for UV exposure and air quality

    Science.gov (United States)

    Nowack, Peer Johannes; Abraham, Nathan Luke; Braesicke, Peter; Pyle, John Adrian

    2016-03-01

    Various forms of geoengineering have been proposed to counter anthropogenic climate change. Methods which aim to modify the Earth's energy balance by reducing insolation are often subsumed under the term solar radiation management (SRM). Here, we present results of a standard SRM modelling experiment in which the incoming solar irradiance is reduced to offset the global mean warming induced by a quadrupling of atmospheric carbon dioxide. For the first time in an atmosphere-ocean coupled climate model, we include atmospheric composition feedbacks for this experiment. While the SRM scheme considered here could offset greenhouse gas induced global mean surface warming, it leads to important changes in atmospheric composition. We find large stratospheric ozone increases that induce significant reductions in surface UV-B irradiance, which would have implications for vitamin D production. In addition, the higher stratospheric ozone levels lead to decreased ozone photolysis in the troposphere. In combination with lower atmospheric specific humidity under SRM, this results in overall surface ozone concentration increases in the idealized G1 experiment. Both UV-B and surface ozone changes are important for human health. We therefore highlight that both stratospheric and tropospheric ozone changes must be considered in the assessment of any SRM scheme, due to their important roles in regulating UV exposure and air quality.

  15. CFD based performance analysis of a solar air heater duct provided with artificial roughness

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Sharad; Saini, R.P. [Alternate Hydro Energy Centre, Indian Institute of Technology Roorkee, AHEC, Roorkee, Uttarakhand 247667 (India)

    2009-05-15

    In the present work the performance of a solar air heater duct provided with artificial roughness in the form of thin circular wire in arc shaped geometry has been analysed using Computational Fluid Dynamics (CFD). The effect of arc shaped geometry on heat transfer coefficient, friction factor and performance enhancement was investigated covering the range of roughness parameter (relative roughness height (e/D) from 0.0299 to 0.0426 and relative roughness angle ({alpha}/90) from 0.333 to 0.666) and working parameter (Reynolds number, Re from 6000 to 18,000 and solar radiation of 1000 W/m2). Different turbulent models have been used for the analysis and their results are compared. Renormalization-group (RNG) k-{epsilon} model based results have been found in good agreement and accordingly this model is used to predict heat transfer and friction factor in the duct. The overall enhancement ratio has been calculated in order to discuss the overall effect of the roughness and working parameters. A maximum value of overall enhancement ratio has been found to be as 1.7 for the range of parameters investigated. (author)

  16. Power generation on a solar photovoltaic modules integrated Lighter-than-Air Platform at a low altitude

    CERN Document Server

    Ghosh, Kuntal; Duttagupta, Siddharth P

    2016-01-01

    Use of lighter than air platforms (aerostats and airships) for reconnaissance and surveillance over long periods can be facilitated by generation of power on-board through solar photovoltaic arrays. Attempts to integrate solar photovoltaic modules on such contoured surfaces leads to multiple challenges ranging from the choice of solar modules, determination of best method of their integration with the lighter than air platform, and design of the array layout in order to optimize the loss of power due to non-uniform illumination. This paper describes the method of designing such a system and suggests strategies for overcoming these challenges. The issue of non-uniform illumination has been tackled by maximum power point tracking using the scanning window technique for maximizing power generation and an algorithm of distributed maximum power point tracking has been suggested for further improvement. The procedure described in this paper can be used for obtaining the optimum power generation capability of a sola...

  17. Numerical study on optical and electric-thermal performance for solar concentrating PV/T air system

    Institute of Scientific and Technical Information of China (English)

    SUN Jian; SHI MingHeng

    2009-01-01

    Hybrid photovoltaic/thermsl(PV/T)system with solar concentrator is an effective way to improve solar energy conversion efficiency.In this work,a single-pass PV/T sir system with a three-trough compound parabolic concentrator(CPC)of concentration ratio 2.0 is designed and the solar incident distributions at the solar cell surface are calculated by ray tracing method.Based on energy balance,the heat transfer models of all main components in this system are developed.The effects of some main designing and operational parameters on the electric-thermal performance of the system are analyzed.The results show that the solar radiation intensity can be higher than 1200 W/m~2 at most area of the cell surface.The temperature of the air and cell surface increases along the length of the system.Thus the system efficiency of the CPC is higher than that of the system without the CPC.The thermal efficiency,exergy and electrical efficiency of this CPC system increase with increasing of the air mass flow rate and the length of the system.With increasing packing fraction the electrical efficiency increases,but the thermal efficiency decreases.The exergy efficiency increases slightly with the packing fraction rising.The data obtained in this work are valuable for the design and operation for this kind of solar concentrating PV/T systems.

  18. Influence of channel depth on the performance of solar air heaters

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Wei; Ji, Jie; He, Wei [Department of Thermal Science and Energy Engineering, University of Science and Technology of China, Hefei, Anhui 230026 (China)

    2010-10-15

    In the design of solar air heaters (SAHs), channel depth is a principal variable to be fixed. In this paper, the effect of the channel depth on the energy gain of type I and type III SAHs has been investigated by computational fluid dynamics (CFD) simulations. Laminar model and k-{omega} turbulence model of Wilcox are used for the prediction of flow and temperature field in SAHs. Our study shows that the heat transfer corresponding to the temperature distribution across the channel in SAH varies greatly with the change of channel depth. Based on the first and second laws of thermodynamics, the optimal channel depths for type I and type III SAHs with black-painted absorber are suggested as 10 mm. It is found that with selective coating, the absorber plate should be further from the cover glazing in order to prevent excessive convective heat loss, the distance is better of no less than 20 mm. In type III SAH, air flows in two channels above and below the absorber plate, the depth ratio of up channel to down channel should be no less than 1. (author)

  19. Computational fluid dynamics for modeling the turbulent natural convection in a double air-channel solar chimney system

    Science.gov (United States)

    Zavala-Guillén, I.; Xamán, J.; Álvarez, G.; Arce, J.; Hernández-Pérez, I.; Gijón-Rivera, M.

    2016-03-01

    This study reports the modeling of the turbulent natural convection in a double air-channel solar chimney (SC-DC) and its comparison with a single air-channel solar chimney (SC-C). Prediction of the mass flow and the thermal behavior of the SC-DC were obtained under three different climates of Mexico during one summer day. The climates correspond to: tropical savannah (Mérida), arid desert (Hermosillo) and temperate with warm summer (Mexico City). A code based on the Finite Volume Method was developed and a k-ω turbulence model has been used to model air turbulence in the solar chimney (SC). The code was validated against experimental data. The results indicate that during the day the SC-DC extracts about 50% more mass flow than the SC-C. When the SC-DC is located in Mérida, Hermosillo and Mexico City, the air-changes extracted along the day were 60, 63 and 52, respectively. The air temperature at the outlet of the chimney increased up to 33%, 38% and 61% with respect to the temperature it has at the inlet for Mérida, Hermosillo and Mexico City, respectively.

  20. Year round performance of double pass solar air heater with packed bed

    Energy Technology Data Exchange (ETDEWEB)

    El-Sebaii, A.A. [Department of Physics, Faculty of Science, Tanta University, El-Geish Street, Tanta, El-Gharbia 31527 (Egypt)]. E-mail: aasebaii@yahoo.com; Aboul-Enein, S. [Department of Physics, Faculty of Science, Tanta University, El-Geish Street, Tanta, El-Gharbia 31527 (Egypt); Ramadan, M.R.I. [Department of Physics, Faculty of Science, Tanta University, El-Geish Street, Tanta, El-Gharbia 31527 (Egypt); El-Bialy, E. [Department of Physics, Faculty of Science, Tanta University, El-Geish Street, Tanta, El-Gharbia 31527 (Egypt)

    2007-03-15

    The thermal performance of a double glass, double pass solar air heater with a packed bed (DGDPSAHPB) was investigated experimentally and theoretically. A suitable computer program was developed for the analytical solution of the energy balance equations for the various elements of the system. Numerical calculations were performed for typical summer days of 2003 using limestone and gravel as packed bed materials. To validate the proposed mathematical model, comparisons between experimental and theoretical results were performed. Good agreement was achieved. Furthermore, the effects of mass flow rate of air m radical{sub f} as well as that of the mass and porosity of the packed bed material on the outlet temperature of air T{sub flo}, thermal output power Q radical{sub u}, pressure drop {delta}P and thermohydraulic efficiency {eta}{sub TH} were also studied. Comparisons between the thermal performances of the system without and with the packed bed, either above or under the absorber plate were performed. Some experiments were also performed using iron scraps as a packed bed material. It was indicated that it is advisable to operate the system with a packed bed of low porosity above the absorber plate. The best performance was achieved with gravel as a packing material above the absorber plate when m radical{sub f} equals 0.05kg/s or lower to provide a lower pressure drop across the system and, therefore, a higher thermohydraulic efficiency {eta}{sub TH}. Values of {eta}{sub TH} with gravel were found to be 22-27% higher than that without the packed bed. The annual averages of T{sub flo} and {eta}{sub TH} were found to be 16.5% and 28.5% higher than those for the system without the packed bed; indicating an improvement of the heater performance on using a packed bed material, above or under the heater absorber, all year round.

  1. Models for predicting thermal performance of packed bed energy storage system for solar air heaters : a review

    Energy Technology Data Exchange (ETDEWEB)

    Singh, R. [Beant College of Engineering and Technology, Gurdaspur, Punjab (India). Dept. of Mechanical Engineering; Saini, R.P. [Alternate Hydro Energy Centre, Roorkee, Uttaranchal (India); Saini, J.S. [Indian Inst. of Technology, Roorkee, Uttarakhand (India). Dept. of Mechanical and Industrial Engineering

    2009-07-01

    Packed beds are typically attached to solar air heaters in order to store the thermal energy of hot air. Mathematical models are needed to predict the performance of the system and to optimize the design of such systems under any given operating parameters. This paper discussed mathematical models reported in the literature for predicting thermal performance of packed bed energy storage system for solar air heaters. The purpose of the paper was to consolidate information for designers. Specifically, the paper discussed the thermal performance of packed beds and described the models that can predict their thermal performance, with particular reference to the two-phase model (Schumann model); intraparticle conduction and dispersion model; single phase model; equivalence of two-phase and single-phase models; Cautier and Farber model; Sagara and Nakahara model; and the Mumma and Marvin model. 24 refs., 3 figs.

  2. Depicting the Dependency of Isoprene in Ambient Air and from Plants on Temperature and Solar Radiation by Using Regression Analysis

    Science.gov (United States)

    Saxena, Pallavi; Ghosh, Chirashree

    2016-07-01

    Among all sources of volatile organic compounds, isoprene emission from plants is an important part of the atmospheric hydrocarbon budget. In the present study, isoprene emission capacity at the bottom of the canopies of plant species viz. Dalbergia sissoo and Nerium oleander and in ambient air at different sites selected on the basis of land use pattern viz. near to traffic intersection with dense vegetation, away from traffic intersection with dense vegetation under floodplain area (Site I) and away from traffic intersection with dense vegetation under hilly ridge area (Site II) during three different seasons (monsoon, winter and summer) in Delhi were measured. In order to find out the dependence of isoprene emission rate on temperature and solar radiation, regression analysis has been performed. In case of dependency of isoprene in ambient air on temperature and solar radiation in selected seasons it has been found that high isoprene was found during summer season as compared to winter and monsoon seasons. Thus, positive linear relationship gives the best fit between temperature, solar rdaiation and isoprene during summer season as compared to winter and monsoon season. On the other hand, in case of isoprene emission from selected plant species, it has been found that high temperature and solar radiation promotes high isoprene emission rates during summer season as compared to winter and monsoon seasons in D. sissoo. Thus, positive linear relationship gives the best fit between temperature, solar radiation and isoprene emission rate during summer season as compared to winter and monsoon season. In contrast, in case of Nerium oleander, no such appropriate relationship was obtained. The study concludes that in ambient air, isoprene concentration was found to be high during summer season as compared to other seasons and gives best fit between temperature, solar radiation and isoprene. In case of plants, Dalbergia sissoo comes under high isoprene emission category

  3. Citywide Impacts of Cool Roof and Rooftop Solar Photovoltaic Deployment on Near-Surface Air Temperature and Cooling Energy Demand

    Science.gov (United States)

    Salamanca, F.; Georgescu, M.; Mahalov, A.; Moustaoui, M.; Martilli, A.

    2016-10-01

    Assessment of mitigation strategies that combat global warming, urban heat islands (UHIs), and urban energy demand can be crucial for urban planners and energy providers, especially for hot, semi-arid urban environments where summertime cooling demands are excessive. Within this context, summertime regional impacts of cool roof and rooftop solar photovoltaic deployment on near-surface air temperature and cooling energy demand are examined for the two major USA cities of Arizona: Phoenix and Tucson. A detailed physics-based parametrization of solar photovoltaic panels is developed and implemented in a multilayer building energy model that is fully coupled to the Weather Research and Forecasting mesoscale numerical model. We conduct a suite of sensitivity experiments (with different coverage rates of cool roof and rooftop solar photovoltaic deployment) for a 10-day clear-sky extreme heat period over the Phoenix and Tucson metropolitan areas at high spatial resolution (1-km horizontal grid spacing). Results show that deployment of cool roofs and rooftop solar photovoltaic panels reduce near-surface air temperature across the diurnal cycle and decrease daily citywide cooling energy demand. During the day, cool roofs are more effective at cooling than rooftop solar photovoltaic systems, but during the night, solar panels are more efficient at reducing the UHI effect. For the maximum coverage rate deployment, cool roofs reduced daily citywide cooling energy demand by 13-14 %, while rooftop solar photovoltaic panels by 8-11 % (without considering the additional savings derived from their electricity production). The results presented here demonstrate that deployment of both roofing technologies have multiple benefits for the urban environment, while solar photovoltaic panels add additional value because they reduce the dependence on fossil fuel consumption for electricity generation.

  4. Citywide Impacts of Cool Roof and Rooftop Solar Photovoltaic Deployment on Near-Surface Air Temperature and Cooling Energy Demand

    Science.gov (United States)

    Salamanca, F.; Georgescu, M.; Mahalov, A.; Moustaoui, M.; Martilli, A.

    2016-04-01

    Assessment of mitigation strategies that combat global warming, urban heat islands (UHIs), and urban energy demand can be crucial for urban planners and energy providers, especially for hot, semi-arid urban environments where summertime cooling demands are excessive. Within this context, summertime regional impacts of cool roof and rooftop solar photovoltaic deployment on near-surface air temperature and cooling energy demand are examined for the two major USA cities of Arizona: Phoenix and Tucson. A detailed physics-based parametrization of solar photovoltaic panels is developed and implemented in a multilayer building energy model that is fully coupled to the Weather Research and Forecasting mesoscale numerical model. We conduct a suite of sensitivity experiments (with different coverage rates of cool roof and rooftop solar photovoltaic deployment) for a 10-day clear-sky extreme heat period over the Phoenix and Tucson metropolitan areas at high spatial resolution (1-km horizontal grid spacing). Results show that deployment of cool roofs and rooftop solar photovoltaic panels reduce near-surface air temperature across the diurnal cycle and decrease daily citywide cooling energy demand. During the day, cool roofs are more effective at cooling than rooftop solar photovoltaic systems, but during the night, solar panels are more efficient at reducing the UHI effect. For the maximum coverage rate deployment, cool roofs reduced daily citywide cooling energy demand by 13-14 %, while rooftop solar photovoltaic panels by 8-11 % (without considering the additional savings derived from their electricity production). The results presented here demonstrate that deployment of both roofing technologies have multiple benefits for the urban environment, while solar photovoltaic panels add additional value because they reduce the dependence on fossil fuel consumption for electricity generation.

  5. Heat transfer and friction factor correlations for a solar air heater duct roughened artificially with multiple v-ribs

    Energy Technology Data Exchange (ETDEWEB)

    Hans, V.S. [Department of Mechanical Engineering, PAU, Ludhiana (Punjab) 141004 (India); Saini, R.P. [Alternate Hydro Energy Centre, Indian Institute of Technology, Roorkee (UA) 247667 (India); Saini, J.S. [Mechanical and Industrial Engineering Department, Indian Institute of Technology, Roorkee (UA) 247667 (India)

    2010-06-15

    The use of artificial roughness on the underside of the absorber plate is an effective and economic way to improve the thermal performance of a solar air heater. Several experimental investigations, involving different types of roughness elements, have been carried out to improve the heat transfer from the absorber plate to air flowing in solar air heaters. This paper presents an experimental investigation carried out to study the effect of multiple v-rib roughness on heat transfer coefficient and friction factor in an artificially roughened solar air heater duct. The experiment encompassed Reynolds number (Re) from 2000 to 20000, relative roughness height (e/D) values of 0.019-0.043, relative roughness pitch (P/e) range of 6-12, angle of attack ({alpha}) range of 30-75 and relative roughness width (W/w) range of 1-10. Extensive experimentation has been conducted to collect data on heat transfer and fluid flow characteristics of a rectangular duct roughened with multiple v-ribs. Using these experimental data, correlations for Nusselt number and friction factor in terms of roughness geometry and flow parameters have been developed. (author)

  6. Energy and exergy analysis of a new flat-plate solar air heater having different obstacles on absorber plates

    Energy Technology Data Exchange (ETDEWEB)

    Akpinar, Ebru Kavak; Kocyigit, Fatih [Mechanical Engineering Department, Firat University, 23279 Elazig (Turkey)

    2010-11-15

    This study experimentally investigates performance analysis of a new flat-plate solar air heater (SAH) with several obstacles (Type I, Type II, Type III) and without obstacles (Type IV). Experiments were performed for two air mass flow rates of 0.0074 and 0.0052 kg/s. The first and second laws of efficiencies were determined for SAHs and comparisons were made among them. The values of first law efficiency varied between 20% and 82%. The values of second law efficiency changed from 8.32% to 44.00%. The highest efficiency were determined for the SAH with Type II absorbent plate in flow channel duct for all operating conditions, whereas the lowest values were obtained for the SAH without obstacles (Type IV). The results showed that the efficiency of the solar air collectors depends significantly on the solar radiation, surface geometry of the collectors and extension of the air flow line. The largest irreversibility was occurring at the SAH without obstacles (Type IV) collector in which collector efficiency is smallest. At the end of this study, the energy and exergy relationships are delivered for different SAHs. (author)

  7. Investigation of heat transfer and friction characteristics of packed bed solar air heater using wire mesh as packing material

    Energy Technology Data Exchange (ETDEWEB)

    Prasad, S.B.; Saini, J.S.; Singh, Krishna M. [Department of Mechanical and Industrial Engineering, Indian Institute of Technology Roorkee, Roorkee 247667 (India)

    2009-05-15

    An experimental investigation has been carried out on a packed bed solar air heater using wire mesh as packing material. Data pertaining to heat transfer and friction characteristics were collected for air flow rates ranging from 0.0159 to 0.0347 kg/s-m{sup 2} for eight sets of matrices with varying geometrical parameters. The thermal efficiency of a packed bed solar air heater was compared with that of a conventional solar air heater to determine the enhancement which was found to be strong function of system and operating parameters of the bed. It was found that an enhancement of the order of 76.9-89.5% can be obtained. Experimental data were utilised to develop correlations for Colburn J{sub h} factor and friction factor as function of geometrical parameters of the bed and the flow Reynolds number. These correlations were found to predict the experimental results with reasonable accuracy. It has also been found that the present correlations show much better agreement as compared to the values predicted by earlier correlations for such systems. (author)

  8. Energy and exergy analysis of a new flat-plate solar air heater having different obstacles on absorber plates

    International Nuclear Information System (INIS)

    This study experimentally investigates performance analysis of a new flat-plate solar air heater (SAH) with several obstacles (Type I, Type II, Type III) and without obstacles (Type IV). Experiments were performed for two air mass flow rates of 0.0074 and 0.0052 kg/s. The first and second laws of efficiencies were determined for SAHs and comparisons were made among them. The values of first law efficiency varied between 20% and 82%. The values of second law efficiency changed from 8.32% to 44.00%. The highest efficiency were determined for the SAH with Type II absorbent plate in flow channel duct for all operating conditions, whereas the lowest values were obtained for the SAH without obstacles (Type IV). The results showed that the efficiency of the solar air collectors depends significantly on the solar radiation, surface geometry of the collectors and extension of the air flow line. The largest irreversibility was occurring at the SAH without obstacles (Type IV) collector in which collector efficiency is smallest. At the end of this study, the energy and exergy relationships are delivered for different SAHs.

  9. Impacts of Photovoltaic Power Plant Sitings and Distributed Solar Panels on Meteorology and Air Quality in Central California

    Science.gov (United States)

    Bastien, L. A.; Jin, L.; Brown, N. J.

    2012-12-01

    California's electric utility companies are required to use renewable energy to produce 20% of their power by 2010 and 33% by 2020. A main source of the power will be solar energy because photovoltaic technologies have advanced so much that large scale installations are being built and will be built in the future with even greater capacity. Rather than being a large emission source, these plants affect the ambient environment through albedo changes and by emission reductions associated with not burning fossil fuels to generate the same amount of electricity. Like conventional power plants, their impact on local meteorology and air quality depends on the specific technology, ambient atmospheric conditions, and the spatial location of the plant. Also, as solar panels on commercial and residential rooftops become even more common, the effect of distributed photovoltaic panels on meteorology and air quality is likely to become significant. In this study, we use the Weather Research and Forecasting (WRF) model and the Community Multiscale Air Quality (CMAQ) model at high resolution of 4 km x 4 km over several 5-day high-ozone episodes of the summer 2000 to assess the impact of photovoltaic panels on meteorology and air quality in Central California. We investigate the effect of locating a 1.0 Giga watt solar plant in different locations and the effect of distributed rooftop photovoltaic panels in major Californian cities, with a focus on peak and 8-hour average ozone and 24-hour average PM2.5.

  10. Solar Cycle and Anthropogenic Forcing of Surface-Air Temperature at Armagh Observatory, Northern Ireland

    Science.gov (United States)

    Wilson, Robert M.

    2010-01-01

    A comparison of 10-yr moving average (yma) values of Armagh Observatory (Northern Ireland) surface-air temperatures with selected solar cycle indices (sunspot number (SSN) and the Aa geomagnetic index (Aa)), sea-surface temperatures in the Nino 3.4 region, and Mauna Loa carbon dioxide (CO2) (MLCO2) atmospheric concentration measurements reveals a strong correlation (r = 0.686) between the Armagh temperatures and Aa, especially, prior to about 1980 (r = 0.762 over the interval of 1873-1980). For the more recent interval 1963-2003, the strongest correlation (r = 0.877) is between Armagh temperatures and MLCO2 measurements. A bivariate fit using both Aa and Mauna Loa values results in a very strong fit (r = 0.948) for the interval 1963-2003, and a trivariate fit using Aa, SSN, and Mauna Loa values results in a slightly stronger fit (r = 0.952). Atmospheric CO2 concentration now appears to be the stronger driver of Armagh surface-air temperatures. An increase of 2 C above the long-term mean (9.2 C) at Armagh seems inevitable unless unabated increases in anthropogenic atmospheric gases can be curtailed. The present growth in 10-yma Armagh temperatures is about 0.05 C per yr since 1982. The present growth in MLCO2 is about 0.002 ppmv, based on an exponential fit using 10-yma values, although the growth appears to be steepening, thus, increasing the likelihood of deleterious effects attributed to global warming.

  11. Thermal Hydraulic Performance in a Solar Air Heater Channel with Multi V-Type Perforated Baffles

    Directory of Open Access Journals (Sweden)

    Anil Kumar

    2016-07-01

    Full Text Available This article presents heat transfer and fluid flow characteristics in a solar air heater (SAH channel with multi V-type perforated baffles. The flow passage has an aspect ratio of 10. The relative baffle height, relative pitch, relative baffle hole position, flow attack angle, and baffle open area ratio are 0.6, 8.0, 0.42, 60°, and 12%, respectively. The Reynolds numbers considered in the study was in the range of 3000–10,000. The re-normalization group (RNG k-ε turbulence model has been used for numerical analysis, and the optimum relative baffle width has been investigated considering relative baffle widths of 1.0–7.0.The numerical results are in good agreement with the experimental data for the range considered in the study. Multi V-type perforated baffles are shown to have better thermal performance as compared to other baffle shapes in a rectangular passage. The overall thermal hydraulic performance shows the maximum value at the relative baffle width of 5.0.

  12. NUMERICAL SIMULATION OF THE AIR FLOW AROUND THE ARRAYS OF SOLAR COLLECTORS

    Directory of Open Access Journals (Sweden)

    Vukman V Bakić

    2011-01-01

    Full Text Available This paper deals with the numerical simulation of air around the arrays of flat plate collectors and determination of the flow field, which should provide a basis for estimating a convective heat losses, a parameter which influences their working characteristics. Heat losses are the result of the reflection on the glass, conductive losses at the collector's absorber plate, radiation of the absorber plate and convective losses on the glass. Wind velocity in the vicinity of the absorber plate depends on its position in the arrays of collectors. Results obtained in the numerical simulation of flow around collectors were used as boundary conditions in modeling of thermal-hydraulic processes inside the solar collector. A method for coupling thermal-hydraulic processes inside the collector with heat transfer from plate to tube bundle was developed, in order to find out the distribution of the temperature of the absorber plate and the efficiency of the flat plate collectors. Analyses of flow around arrays of collectors are preformed with RNG k - ε model. Three values for free-stream velocity were analysed, i.e. 1 m/s, 5 m/s and 10 m/s, as well as two values for the angle between the ground and the collector (20° and 40°. Heat transfer coefficient was determined from the theory of boundary layer. Heat transfer inside the plate cavity was analyzed assuming constant intensity of radiation.

  13. Flexible inverted polymer solar cells fabricated in air at low temperatures

    Science.gov (United States)

    Kuwabara, Takayuki; Wang, Xiaofan; Kusumi, Takuji; Yamaguchi, Takahiro; Taima, Tetsuya; Takahashi, Kohshin

    2016-08-01

    A series of modified indium tin oxide (ITO) materials, including sol-gel zinc-oxide-coated ITO (ITO/ZnO), ZnO nanoparticle-coated ITO (ITO/ZnO-NP), 1,4-bis(3-aminopropyl)piperazine (BAP)-modified ITO, and polyethylenimine ethoxylated (PEIE)-modified ITO, were used for electron-collection electrodes in inverted polymer solar cells (PSCs). The modified ITO electrodes were prepared in air at temperatures below 100 °C, using various ITO films on flexible poly(ethylene terephthalate) substrates (PET-ITO) with sheet resistances ranging from 12 to 60 Ω sq-1. The PET-ITO (12 Ω sq-1)/ZnO-NP PSC exhibited an improved power conversion efficiency (PCE) (2.93%), and this PCE was ˜90% of that observed for a cell using glass-ITO/ZnO-NP (sheet resistance = 10 Ω sq-1 PCE = 3.28%). Additionally, we fabricated a flexible inverted ZnO-NP PSC using an indene-C60 bisadduct (ICBA) as the acceptor material in place of [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) and obtained a PCE of 4.18%.

  14. Air Temperature Error Correction Based on Solar Radiation in an Economical Meteorological Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Xingming Sun

    2015-07-01

    Full Text Available Air temperature (AT is an extremely vital factor in meteorology, agriculture, military, etc., being used for the prediction of weather disasters, such as drought, flood, frost, etc. Many efforts have been made to monitor the temperature of the atmosphere, like automatic weather stations (AWS. Nevertheless, due to the high cost of specialized AT sensors, they cannot be deployed within a large spatial density. A novel method named the meteorology wireless sensor network relying on a sensing node has been proposed for the purpose of reducing the cost of AT monitoring. However, the temperature sensor on the sensing node can be easily influenced by environmental factors. Previous research has confirmed that there is a close relation between AT and solar radiation (SR. Therefore, this paper presents a method to decrease the error of sensed AT, taking SR into consideration. In this work, we analyzed all of the collected data of AT and SR in May 2014 and found the numerical correspondence between AT error (ATE and SR. This corresponding relation was used to calculate real-time ATE according to real-time SR and to correct the error of AT in other months.

  15. Flexible inverted polymer solar cells fabricated in air at low temperatures

    Science.gov (United States)

    Kuwabara, Takayuki; Wang, Xiaofan; Kusumi, Takuji; Yamaguchi, Takahiro; Taima, Tetsuya; Takahashi, Kohshin

    2016-08-01

    A series of modified indium tin oxide (ITO) materials, including sol–gel zinc-oxide-coated ITO (ITO/ZnO), ZnO nanoparticle-coated ITO (ITO/ZnO-NP), 1,4-bis(3-aminopropyl)piperazine (BAP)-modified ITO, and polyethylenimine ethoxylated (PEIE)-modified ITO, were used for electron-collection electrodes in inverted polymer solar cells (PSCs). The modified ITO electrodes were prepared in air at temperatures below 100 °C, using various ITO films on flexible poly(ethylene terephthalate) substrates (PET–ITO) with sheet resistances ranging from 12 to 60 Ω sq‑1. The PET–ITO (12 Ω sq‑1)/ZnO-NP PSC exhibited an improved power conversion efficiency (PCE) (2.93%), and this PCE was ∼90% of that observed for a cell using glass–ITO/ZnO-NP (sheet resistance = 10 Ω sq‑1 PCE = 3.28%). Additionally, we fabricated a flexible inverted ZnO-NP PSC using an indene-C60 bisadduct (ICBA) as the acceptor material in place of [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) and obtained a PCE of 4.18%.

  16. Heat transfer and friction correlations for artificially roughened solar air heater duct with discrete W-shaped ribs

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Arvind; Bhagoria, J.L.; Sarviya, R.M. [Department of Mechanical Engineering, M.A.N.I.T, Bhopal 462 051, MP (India)

    2009-08-15

    An experimental investigation has been carried out to study the heat transfer and friction characteristics in solar air heater by using discrete W-shaped roughness on one broad wall of solar air heater with an aspect ratio of 8:1, the roughened wall being heated while the remaining three walls are insulated. The experiment encompassed Reynolds number (Re) range from 3000 to 15,000, relative roughness height (e/D{sub h}) in the range of 0.0168-0.0338, relative roughness pitch (p/e) 10 and the angle of attack ({alpha}) in the range of 30-75 . The effect of parameters on the heat transfer and friction are compared with the result of smooth duct under similar flow conditions. Correlations for heat transfer and friction have been developed as a function of roughness and flow parameters. (author)

  17. Delta XTE Spacecraft Solar Panel Deployment, Hangar AO at Cape Canaveral Air Station

    Science.gov (United States)

    1995-01-01

    The footage shows technicians in the clean room checking and adjusting the deployment mechanism of the solar panel for XTE spacecraft. Other scenes show several technicians making adjustments to software for deployment of the solar panels.

  18. Control strategies study of a complete solar assisted air conditioning system in an office building using TRNSYS

    OpenAIRE

    Thomas, Sébastien; Andre, Philippe

    2009-01-01

    It is now clearly assumed that solar assisted air conditioning is able to minimize environmental impact and CO2 production of buildings operation. How to reach highest energy savings is still a work in progress. In former literature, equipment control has been point out as a critical feature of energy consumption. Control becomes more and more important as system is complex. The complete simulation environment was developed in previous work, it includes the absorption chiller ...

  19. Collector Efficiency in Downward-Type Double-Pass Solar Air Heaters with Attached Fins and Operated by External Recycle

    OpenAIRE

    Chii-Dong Ho; Ho-Ming Yeh

    2012-01-01

    The collector efficiency in a downward-type double-pass external-recycle solar air heater with fins attached on the absorbing plate has been investigated theoretically. Considerable improvement in collector efficiency is obtainable if the collector is equipped with fins and the operation is carried out with an external recycle. Due to the recycling, the desirable effect of increasing the heat transfer coefficient compensates for the undesirable effect of decreasing the driving force (temperat...

  20. Effect of chamfering on heat transfer and friction characteristics of solar air heater having absorber plate roughened with compound turbulators

    Energy Technology Data Exchange (ETDEWEB)

    Layek, Apurba [Department of Mechanical Engineering, NIT Durgapur, West Bengal 713 209 (India); Saini, J.S.; Solanki, S.C. [Department of Mechanical and Industrial Engineering, IIT Roorkee, Roorkee, Uttarakhand 247 667 (India)

    2009-05-15

    Artificial roughness in the form of repeated transverse chamfered rib-groove roughness on one broad wall has been proposed as a convenient method for enhancement of thermal performance of solar air heater. An experimental investigation on heat and fluid flow characteristics of fully developed turbulent flow in a rectangular duct having repeated integral transverse chamfered rib-groove roughness on one broad wall has been carried out. The roughened wall is uniformly heated while the remaining three walls are insulated. These boundary conditions correspond closely to those found in solar air heaters. Six roughened plates have been tested placing a 60 V-groove at the centre line in between two consecutive chamfered ribs. The ribs' top have been chamfered having chamfer angles of 5 , 12 , 15 , 18 , 22 and 30 , while relative roughness pitch (P/e) and relative roughness height (e/D{sub h}) of the ribs were kept constant having values of 10 and 0.03 respectively. The flow Reynolds number of the duct varied in the range of approximately 3000-21,000, most suitable for solar air heater. The effects of chamfer angle on Nusselt number and friction factor have been discussed and the results are compared with the square rib-grooved and smooth duct under similar flow conditions to investigate the enhancement in Nusselt number and friction factor. The conditions for the maximum enhancement of Nusselt number and friction factor have been determined. It has been found that the thermo-hydraulic performance of the solar air heater provided with such roughness is considerably enhanced. (author)

  1. An economic optimization of evaporator and air collector area in a solar assisted heat pump drying system

    International Nuclear Information System (INIS)

    Highlights: • The optimum combination will provide around 89% of the total load. • The system has a savings during the life cycle with least payback period of 4.37 year. • The optimal system is insensitive to the variation in fuel inflation and discount rate. - Abstract: This paper presents an economic optimization of evaporator and air collector area of a solar assisted heat pump drying system. Economic viability of solar heating systems is usually made by comparing the cost flows recurring throughout the lifetime of the solar and conventional alternative systems. Therefore, identification of optimum variables by using a simulation program and an economic analysis based on payback period of the system are presented in this paper. FORTRAN language is used to run the simulation. Effect of load and different economic variables on payback period is also investigated. Economic analysis reveals that system has sufficient amount of savings during the life cycle with a minimum payback period of about 4 years

  2. Performance evaluation of a natural-convection solar air-heater with a rectangular-finned absorber plate

    Energy Technology Data Exchange (ETDEWEB)

    Fakoor Pakdaman, M.; Lashkari, A.; Basirat Tabrizi, H.; Hosseini, R. [Department of Mechanical Engineering, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of)

    2011-02-15

    This paper deals with an experimental investigation to evaluate different thermal characteristics of a natural-convection flat-plate solar air-heater with longitudinal rectangular fins array. Having determined the thermal performance of the system a Nusselt number correlation is presented for such finned duct devices. In the presented empirical model which may have industrial applications, solar radiation and ambient temperature have been considered as independent parameters. Other characteristics of the system such as different dimensionless variables, plates and outflow temperatures, efficiency, and mass flow rate have been empirically modeled based on these variables. The particular difference in this study in comparison with the other similar studies is the presentation of an empirical model for rectangular-finned solar air-heaters. This model proposes design concepts and rules of thumb, and demonstrates the calculations of the design parameters. Based on the order of magnitude analysis, solar radiation has been found to be the main parameter which characterizes the thermal behavior of the system. Besides, exergy analysis has been carried out, and optimum conditions in which the system has the highest performance have been determined. (author)

  3. Analisa Kinerja Termal Solar Apparatus Panel pada Alat Destilasi Air Payau dengan Sistem Evaporasi Uap Tenaga Matahari Menggunakan CFD

    Directory of Open Access Journals (Sweden)

    Nadia Handayani

    2014-09-01

    Full Text Available Upaya penyaluran air bersih ke daerah pesisir belum dilakukan secara merata sehingga masyarakat masih mengkonsumsi air payau untuk kehidupan sehari-hari. Meskipun telah banyak dikembangkan alat destilasi air laut menjadi air tawar, namun masih memiliki sistem yang kompleks dan biaya yang mahal, sehingga dikembangkan alat destilasi air menggunakan sistem evaporasi uap dengan sumber tenaga matahari. Untuk mengetahui kinerja termal alat destilasi ini, maka dilakukan penelitian dengan metode simulasi menggunakan pendekatan computational fluid dynamic (CFD menggunakan software GAMBIT 2.4.6 dalam tahap pembuatan domain yang selanjutnya disimulasikan menggunakan software ANSYS FLUENT 13. Simulasi dilakukan pada solar apparatus panel secara three dimensional (3D menggunakan model turbulensi Realizable k-ε, solar load model dan model radiasi Rosseland. Selanjutnya, simulasi dilakukan dengan variasi kecepatan masuk aliran air ke dalam pipa yaitu 0.01 m/s, 0.02 m/s, 0.03 m/s dan 0.04 m/s. Dari hasil pemodelan dan analisa diketahui bahwa distribusi temperatur terbesar terdapat pada pipa. Energi maksimum yang dapat diterima oleh air adalah 369.591 W/m2 pada pukul 10.00 dengan kecepatan 0.04 m/s. Nilai heat losses yang terjadi pada masing-masing kecepatan berbanding terbalik dengan nilai efisiensi yang menurun setiap jam, rata-rata efisiensi terjadi pada sore hari mulai dari pukul 11.00 – 13.00. Nilai efisiensi rata-rata pada kecepatan 0.01 m/s yaitu 27.6%. Pada kecepatan 0.02 yaitu 30.2%. Pada kecepatan 0.03 yaitu 31.6% sedangkan pada kecepatan 0.04 yaitu 33.4%.

  4. Optimal thermo-hydraulic performance of solar air heater having chamfered rib-groove roughness on absorber plate

    Directory of Open Access Journals (Sweden)

    Apurba Layek

    2010-07-01

    Full Text Available The use of an artificial roughness on a surface is an effective technique to enhance the rate of heat transfer to fluid flow in the duct of solar air heater. However, the increase in thermal energy gain is always accompanied by increase in pumping power. This paper is concerned with optimization of roughness parameters of solar air heater based on effective efficiency criterion. Effective efficiency of a solar air heater having repeated transverse chamfered rib–groove roughness on one broad wall has been computed using the correlations for heat transfer and friction factor developed within the investigated range of operating and system parameters. Roughness parameters viz. relative roughness pitch P/e, relative groove position g/P, chamfer angle , relative roughness height e/Dh and flow Reynolds number Re, have a combined effect on the heat transfer as well as fluid friction. The thermo-hydraulic performance of an air heater in terms of effective efficiency is determined on the basis of actual thermal energy gain subtracted by the primary energy required to generate power needed for pumping air through the roughened duct. Based on energy transfer mechanism to the absorber plate, a mathematical model is developed to compute effective efficiency. The selection of the optimal values of the roughness parameters involves the comparison of the enhancement of thermal performance and the increase of pumping losses as a result of using roughness in the collector system with that of the system without roughness. The effective efficiency criterion is maximized and reasonably optimized designs of roughness are found.

  5. Optimal thermo-hydraulic performance of solar air heater having chamfered rib-groove roughness on absorber plate

    Energy Technology Data Exchange (ETDEWEB)

    Layek, Apurba [Department of Mechanical Engineering, National Institute of Technology, Durgapur 713 209 (India)

    2010-07-01

    The use of an artificial roughness on a surface is an effective technique to enhance the rate of heat transfer to fluid flow in the duct of solar air heater. However, the increase in thermal energy gain is always accompanied by increase in pumping power. This paper is concerned with optimization of roughness parameters of solar air heater based on effective efficiency criterion. Effective efficiency of a solar air heater having repeated transverse chamfered rib-groove roughness on one broad wall has been computed using the correlations for heat transfer and friction factor developed within the investigated range of operating and system parameters. Roughness parameters viz. relative roughness pitch P/e, relative groove position g/P, chamfer angle, relative roughness height e/Dh and flow Reynolds number Re, have a combined effect on the heat transfer as well as fluid friction. The thermo-hydraulic performance of an air heater in terms of effective efficiency is determined on the basis of actual thermal energy gain subtracted by the primary energy required to generate power needed for pumping air through the roughened duct. Based on energy transfer mechanism to the absorber plate, a mathematical model is developed to compute effective efficiency. The selection of the optimal values of the roughness parameters involves the comparison of the enhancement of thermal performance and the increase of pumping losses as a result of using roughness in the collector system with that of the system without roughness. The effective efficiency criterion is maximized and reasonably optimized designs of roughness are found.

  6. Photo-degradation in air of the active layer components in a thiophene-quinoxaline copolymer:fullerene solar cell.

    Science.gov (United States)

    Hansson, Rickard; Lindqvist, Camilla; Ericsson, Leif K E; Opitz, Andreas; Wang, Ergang; Moons, Ellen

    2016-04-28

    We have studied the photo-degradation in air of a blend of [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) and poly[2,3-bis-(3-octyloxyphenyl)quinoxaline-5,8-diyl-alt-thiophene-2,5-diyl] (TQ1), and how the photo-degradation affects the solar cell performance. Using near-edge X-ray absorption fine structure (NEXAFS) spectroscopy, changes to the electronic structure of TQ1 and PCBM caused by illumination in ambient air are investigated and compared between the pristine materials and the blend. The NEXAFS spectra show that the unoccupied molecular orbitals of TQ1 are not significantly changed by the exposure of pristine TQ1 to light in air, whereas those of PCBM are severely affected as a result of photo-induced degradation of PCBM. Furthermore, the photo-degradation of PCBM is accelerated by blending it with TQ1. While the NEXAFS spectrum of TQ1 remains unchanged upon illumination in air, its valence band spectrum shows that the occupied molecular orbitals are weakly affected. Yet, UV-Vis absorption spectra demonstrate photo-bleaching of TQ1, which is attenuated in the presence of PCBM in blend films. Illumination of the active layer of TQ1:PCBM solar cells prior to cathode deposition causes severe losses in electrical performance.

  7. Experimental Investigation on Turbulent Convection in Solar Air Heater Channel Fitted with Delta Winglet Vortex Generator

    Institute of Scientific and Technical Information of China (English)

    Sompol Skullong; Pongjet Promvonge

    2014-01-01

    The paper presents an experimental study on the heat transfer and flow friction characteristics in a solar air heater channel fitted with delta-winglet type vortex generators (DWs). The experiments are conducted by vary-ing the airflow rate for Reynolds number in the range of 5000 to 24000 in the test section with a uniform heat-flux applied on the upper channel wall. Firstly, the DW pairs are mounted only at the entrance of the lower wall of the test channel (called DW-E) to create multiple vortex flows at the entry. The effect of two transverse pitches (RP=Pt/H=1 and 2) at three attack angles (α=30°, 45° and 60°) of the DW-E with its relative height, b/H=0.5 (half height of channel) is examined. Secondly, the 30° DWs with three different relative heights (b/H=0.3, 0.4 and 0.5) are placed on the upper wall only (absorber plate, called DW-A) of the test channel. The experimental result reveals that in the first case, the 60° DW-E at RP=1 provides the highest heat transfer and friction factor while the 30° DW-E at RP=1 performs overall better than the others. In the second case, the 30° DW-A at b/H=0.5 yields the highest heat transfer and friction factor but the best thermal performance is found at b/H=0.4.

  8. Thermal Performance Evaluation of the 200kWth SolAir Volumetric Solar Receiver

    Energy Technology Data Exchange (ETDEWEB)

    Tellez Sufrategui, F. M.

    2003-07-01

    The goal of the Solair project the design and test of a fully modular, high efficient and durable open volumetric high-flux receiver, which can be easily and safety operated at mean air outlet temperatures of up to 800 degree centigree. The project was thought in two phases, in the first one an advanced 200 kW Hitrec receiver called Solair 200 was designed and tested. The Solair 200 was built like one single receiver module (subassembly), to test the thermal performance of the receiver as well as the receiver module behavior. Out of a set of these receiver modules have been developed to assemble the 3 MWth receiver in the second phase of the project. This report describes the used procedure or methodology for data processing for thermal performance evaluation purposes and the data processing results for the first phase of the project. Test campaign started in March 2002 and produced fifty data sheets (each corresponding to a test day) and ended in February 2003. During the test phase three absorber material types (or configurations) have been tested during the test campaign. The data processing and evaluation results show that performance goals for the receiver have been fully accomplished. Temperatures of more than 800 degree centigree were achieved for the first two configurations in five test days. For the two absorber configurations for which incident solar power was measured the estimated efficiency at 700 degree centigree was 81 ({+-}6)% for configuration 1 and 83({+-}6)% for configuration 2 of the absorber. (Author). 20 refs.

  9. Performance Evaluation of a Solar Dryer with Finny, Perforated Absorber Plate Collector Equipped with an Air Temperature Control System for Dill Drying

    Directory of Open Access Journals (Sweden)

    M Razmipour

    2016-04-01

    Full Text Available Dill is one of the most important plants in the world because of its medicinal properties and it is widely used as a vegetable in the most parts of Iran. In the present study a new solar dryer with finny, perforated absorber plate collector was utilized to dry fresh dill. The dryer was comprised of a solar collector, a product container, a fan and a drying air temperature controller. The temperature controller was used as a control system to regulate the drying air temperature. Thermal performance of the dryer with finny, perforated solar collector was compared with that of a simple flat plate solar collector at different airflow rates. The effect of drying air temperature at three levels (45, 55 and 65 °C, the product size at three lengths (3, 5 and 7 cm and two different modes of drying (mixed and indirect on the dryer performance was investigated. The results showed that the finny, perforated absorber plate solar collector could improve the thermal efficiency about 11% in comparison with the flat plate collector and the highest thermal efficiency was achieved at the maximum airflow rate. Meanwhile, increasing the air temperature and decreasing the product size caused a significant reduction in energy consumption. Solar fraction reduced by increasing the air temperature. Finally a maximum dryer efficiency of 70% was observed at air temperature of 65 oC, product size of 3 cm with mixed mode drying.

  10. Modeling of solar heating and air conditioning. Progress report, October 31, 1974--December 31, 1975

    Energy Technology Data Exchange (ETDEWEB)

    Duffie, J.A.; Beckman, W.A.

    1975-12-31

    The principal objective of the research is to develop the means to identify and optimize practical systems for heating and cooling of buildings with solar energy in the United States. This will be done through simulation methods. Secondary objectives are to: extend and refine TRNSYS (a modular solar energy system simulation program); develop the means of supporting TRNSYS users in other laboratories; use TRNSYS (and other simulation programs) to develop design procedures for solar heating and cooling processes; design and evaluate an experimental solar heating system on a Wisconsin farm residence.

  11. Performance analysis of solar air cooled double effect LiBr/H2O absorption cooling system in subtropical city

    International Nuclear Information System (INIS)

    Highlights: • The meteorological data during the working period of air conditioning was measured. • The suitable working range of collector temperature of system was gotten. • The characteristic of hourly and monthly total efficiency of system were obtained. • The yearly performance of system was calculated. - Abstract: Due to the absence of cooling tower and independent on water, the air cooled solar double effect LiBr/H2O absorption cooling system is more convenient to be used in commercial building and household use. The performance with collector temperature is an important field for such system. The paper mainly deals with the performance with collector temperature for the solar air cooled double effect LiBr/H2O absorption cooling system in subtropical city. The parameters of system are: aperture area of collector array is 27 m2, tilted angle of collector with respect to the horizontal plane is 20 toward to south evaporator temperature is 5 °C and the cooling capacity is 20 kW. The simulation is based on the meteorological data of monthly typical day which was summarized from a year round measured data. A corresponding parametric model was developed. The hourly and average performance with the collector temperature for monthly typical day was obtained and discussed. It was found that the suitable working range of inlet temperature of collector is 110–130 °C to improve performance and lower the risk of crystallization. The difference of hourly total efficiency in 9:00–16:00 is less, and the monthly total efficiency from May to October is approximate. The yearly performance of system including total efficiency, cooling capacity per area of collector and solar fraction was given. Furthermore, the effect of effectiveness of heat exchanger and pressure drop on total efficiency and solar fraction was studied and compared. The paper can serve as a preliminary investigation of solar air cooled double effect LiBr/H2O absorption cooling system in

  12. Development of residential solar air conditioning system for electricity power peak cut 3

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Gwon Jong [Korea Inst. of Energy and Resources, Daeduk (Korea, Republic of)

    1995-12-31

    In this research, the converter rectifier unit of the inverter air conditioner is substituted into the bidirectional PWM converter. The DC/DC power converter is established on the DC link between the photovoltaic array and the inverter air conditioner, and the photovoltaic air conditioning system which can be parallel driven which utility is developed. (author). 35 ref., 112 figs.

  13. Assessing the transferability of support vector machine model for estimation of global solar radiation from air temperature

    International Nuclear Information System (INIS)

    Highlights: • Transferability of SVM in estimation of solar radiation is investigated. • Radiation at estimation site could be well estimated by SVM developed at source site. • A strategy for selecting a suitable source site is presented. • SVM accuracy is affected by distance and temperature difference between two sites. • RMSE of SVM shows logarithm or linearly relationship with altitude of source site. - Abstract: Exploring novel methods for estimation of global solar radiation from air temperature has been being a focus in many studies. This paper evaluates the transferability of support vector machines (SVM) for estimation of solar radiation in subtropical zone in China. Results suggest that solar radiation at one site (estimation site) could be well estimated by SVM model developed at another site (source site). The accuracy of estimation is affected by the distance and temperature difference between two sites, and altitude of source site. Higher correlations between RMSE of SVM and distance, and temperature differences are observed in northeastern region, increasing the reliability and confidence of SVM model developed at nearby stations. While lower correlations between RMSE and distance, and temperature differences are observed in southwest plateau region. When the altitude of estimation site is lower than 1200 m, RMSE show logarithm relationship with altitude of source sites where the altitude are lower than that of estimation site. Otherwise, RMSE show linearly relationship with altitude of source sites where the altitude are higher than 200 m but lower than that of the estimation site. This result suggests that solar radiation could be also estimated using SVM model developed at the site with similar but lower altitude. Based on these results, a strategy that takes into account the climatic conditions, topography, distance, and altitude for selecting a suitable source site is presented. The findings can guide and ease the appropriate choice of

  14. Energetic performances of an optimized passive Solar Heating Prototype used for Tunisian buildings air-heating application

    International Nuclear Information System (INIS)

    Highlights: • The study of a Solar Heating Prototype to prevail the buildings air-heating needs. • A parametric study of the system was achieved by means of the TRNSYS program. • The monthly internal temperature during cold months ranges between 22 and 25 °C. • The results shows that the relative humidity inside the monozone room of about 40%. - Abstract: This paper deals with the energetic performances of a Solar Heating Prototype (SHP) conceived in our laboratory to prevail the Tunisian households’ air-heating needs. The conceived SHP mainly consists of a flat-plate solar collector, solar hot water tank and an active layer integrated inside a single room. Firstly, a complete model is formulated taking into account various modes of heat transfer in the SHP by means of the TRNSYS simulation program. To validate the TRNSYS model, experimental tests under local weather conditions were performed for 2 days spread over 2 months (March and April 2013). Predicted results were compared to the measurements in order to determine the accuracy of the simulation program. A parametric study was then achieved by means of the TRNSYS program in order to optimize SHP design parameters (Collector area, collector mass flow rate, floor mass flow rate, storage tank volume and thickness of the active layer). The optimization of all design parameters shows that to achieve a maximum performances from the SHP it is essential to use a solar collector with an area equal to 6 m2 area, a collector mass flow rate equal to 100 kg h−1 and a hot water storage tank with a capacity equal to 450 l. Concerning the floor heating, the optimal values of mass flow rate and the active layer thickness are 200 kg h−1 and 0.06 m, respectively. The long-term SHP performances were afterward evaluated by means of the Typical Meteorological Year (TMY) data relative to Tunis, Tunisia. Results showed that for an annual total solar insolation of about 6493.37 MJ m−2 the average solar fraction

  15. Owens-Illinois subsystem design package for the SEC-601 air-cooled solar collector

    Science.gov (United States)

    1979-01-01

    The subsystem design of the SEC-601 solar collector was evaluated. The collector is of modular design and is approximately 12 feet three inches wide and eight feet seven inches tall. It contains 72 collector tube elements and weighs approximately 300 pounds. Included in this report are the subsystem performance specifications and the assembly and installation drawings of the solar collectors and manifold.

  16. Experimental study on the thermal performance and pressure drop of a solar air collector based on flat micro-heat pipe arrays

    International Nuclear Information System (INIS)

    Highlights: • A new type of solar air collector by using flat micro-heat pipe arrays is proposed. • Thermal efficiency rates in summer and winter are approximately 73% and 56%. • The pressure loss is below 25 Pa when the volume flow rate is less than 201.6 m3/h. - Abstract: A new solar air collector that combines the use of flat micro-heat pipe arrays (FMHPA) and evacuated tube is developed and investigated. Using FMHPA as the central transporting component in a solar air collector is an effective approach to improve the collector’s thermal properties and reduce its pressure drop. The thermal properties and pressure drop of the FMHPA solar air collector are analyzed in detail. The main objective of this paper is to report test results of the FMHPA solar air collectors which includes the effects of different seasons and airflow rates on the thermal efficiency and the pressure drop of the air collector. In summer, the thermal efficiency of the collector reaches 73% under stable operation. In the testing airflow range condition, the pressure drop is less than 25 Pa when the flow rate is below 201.6 m3/h. The relative uncertainty of thermal efficiency is approximately 7.73%

  17. Standard Test Method for Water Penetration of Flat Plate Solar Collectors by Uniform Static Air Pressure Difference

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1986-01-01

    1.1 This test method covers the determination of the resistance of flat plate solar collectors to water penetration when water is applied to their outer surfaces with a static air pressure at the outer surface higher than the pressure at the interior of the collector. 1.2 This test method is applicable to any flat plate solar collector. 1.3 The proper use of this test method requires a knowledge of the principles of pressure and deflection measurement. 1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific precautionary information is contained in Section 6.

  18. High temperature collecting performance of a new all-glass evacuated tubular solar air heater with U-shaped tube heat exchanger

    International Nuclear Information System (INIS)

    Highlights: • A novel solar air heater with simplified CPC and U-type heat exchanger is designed and tested. • The system is made up of 10 linked collecting panels. • Simplified CPC has a much lower cost at the expense of slight efficiency loss. • The air heater can propose the heated air exceeding 200 °C with great air flow rate. - Abstract: Experiment and simulation are conducted on a new-type all-glass evacuated tubular solar air heater with simplified compound parabolic concentrator (CPC). The system is made up of 10 linked collecting panels and each panel includes a simplified CPC and an all-glass evacuated tube with a U-shaped copper tube heat exchanger installed inside. Air is gradually heated when passing through each U-shaped copper tube. The heat transfer model of the solar air heater is established and the outlet air temperature, the heat power and heat efficiency are calculated. Calculated and experimental results show that the present experimental system can provide the heated air exceeding 200 °C. The whole system has an outstanding high-temperature collecting performance and the present heat transfer model can meet the general requirements of engineering calculations

  19. Air

    Science.gov (United States)

    ... house) Industrial emissions (like smoke and chemicals from factories) Household cleaners (spray cleaners, air fresheners) Car emissions (like carbon monoxide) *All of these things make up “particle pollution.” They mostly come from cars, trucks, buses, and ...

  20. Modelling the thermodynamic performance of a concentrated solar power plant with a novel modular air-cooled condenser

    International Nuclear Information System (INIS)

    This paper aims at developing a novel air-cooled condenser for concentrated solar power plants. The condenser offers two significant advantages over the existing state-of-the-art. Firstly, it can be installed in a modular format where pre-assembled condenser modules reduce installation costs. Secondly, instead of using large fixed speed fans, smaller speed controlled fans are incorporated into the individual modules. This facility allows the operating point of the condenser to change and continuously maximise plant efficiency. A thorough experimental analysis was performed on a number of prototype condenser designs. This analysis investigated the validly and accuracy of correlations from literature in predicting the thermal and aerodynamic characteristics of different designs. These measurements were used to develop a thermodynamic model to predict the performance of a 50 MW CSP (Concentrated Solar Power) plant with various condenser designs installed. In order to compare different designs with respect to the specific plant capital cost, a techno-economic analysis was performed which identified the optimum size of each condenser. The results show that a single row plate finned tube design, a four row, and a two row circular finned tube design are all similar in terms of their techno-economic performance and offer significant savings over other designs. - Highlights: • A novel air cooled condenser for CSP (Concentrated Solar Power) applications is proposed. • A thorough experimental analysis of various condenser designs was performed. • Heat transfer and flow friction correlations validated for fan generated air flow. • A thermodynamic model to calculate CSP plant output is presented. • Results show the proposed condenser design can continually optimise plant output

  1. 太阳能辐射空调器的研究%On Solar Radiant Air-conditioner

    Institute of Scientific and Technical Information of China (English)

    周亚东; 王军

    2014-01-01

    The paper introduces a solar radiant air-conditioner [1], which supplies heating and cooling for an office hall in one of the colleges in Haikou, Hainan. The system of the solar radiant air-conditioner uses solar water cooler and capillary network. The composition of the system is presented, and the major energy-saving parts of the system and the energy-saving performance ratio of the conventional temperature difference in air conditioning are analyzed from the thermodynamic theory. After running half a year, the system achieved the effects of substantial energy saving and reducing the thermal pollution of the environ-ment from the test data of the indicators. The system has the advantages of low investment and high utiliza-tion rate of the equipments.%介绍一种太阳能辐射空调器[1],为海南省海口市某学院办公事务大厅提供制冷的案例。系统用太阳冷水器与毛细管网相结合,介绍了其系统组成,并用热力学理论分析了本系统各主要节能部分与常规温差空调的节能效能比。系统运行半年,从各项指标检测数据看,取得了大幅节约能源,减少了对环境热污染的效果。该系统初投资少,设备利用率高,对今后的推广有一定的指导作用。

  2. Experimental study of Nusselt number and Friction factor in solar air heater duct with Diamond shaped rib roughness on absorber plate

    Directory of Open Access Journals (Sweden)

    S. S. Pawar

    2013-01-01

    Full Text Available - Solar air heater is used to heat air but it has low thermal efficiency because of low thermal conductivity between air and absorber plate. Thermal efficiency of solar air heater can be improved by creating artificial roughness on absorber plate which causes higher temperature to absorber plate and hence maximum thermal losses occurs to atmosphere. There are number of parameters which enhances the thermal conductivity such as relative roughness height (e/Dh, relative roughness pitch (P/e, Reynolds number (Re, and angle of attack (α.Experimental investigations were carried out to study heat transfer enhancement using diamond shape rib on absorber plate of solar air heater. Absorber plate is heated with the solar radiation in outdoor experiment whereas electric heater is used for indoor experiment. Setup is isolated from the three sides with Thermocol. The relative roughness pitch (p/e varies from 10 to 25 mm. The roughened wall has relative roughness height (e/Dh of 0.023mm and 0.028mm, angle of attack (α is 0° degree, rib height (e is 1 mm and 1.25 mm. Duct aspect ratio (W/H=8, rate of air flow corresponds to Reynolds no. (Re ranging from 3000-14000.Finally comparison of heat transfer and friction factor from both smooth and roughened plate under the similar condition of air flow is made.

  3. Perspective: Maintaining surface-phase purity is key to efficient open air fabricated cuprous oxide solar cells

    Science.gov (United States)

    Hoye, Robert L. Z.; Brandt, Riley E.; Ievskaya, Yulia; Heffernan, Shane; Musselman, Kevin P.; Buonassisi, Tonio; MacManus-Driscoll, Judith L.

    2015-02-01

    Electrochemically deposited Cu2O solar cells are receiving growing attention owing to a recent doubling in efficiency. This was enabled by the controlled chemical environment used in depositing doped ZnO layers by atomic layer deposition, which is not well suited to large-scale industrial production. While open air fabrication with atmospheric pressure spatial atomic layer deposition overcomes this limitation, we find that this approach is limited by an inability to remove the detrimental CuO layer that forms on the Cu2O surface. Herein, we propose strategies for achieving efficiencies in atmospherically processed cells that are equivalent to the high values achieved in vacuum processed cells.

  4. Performance prediction of solar air heater having roughened duct provided with transverse and inclined ribs as artificial roughness

    Energy Technology Data Exchange (ETDEWEB)

    Varun; Patnaik, Amar; Siddhartha [Mechanical Engg Dept., NIT, Hamirpur 177005 (India); Saini, R.P.; Singal, S.K. [AHEC, IIT, Roorkee 247667 (India)

    2009-12-15

    An experimental study has been carried out to investigate the effective efficiency of a solar air heater duct provided with transverse and inclined ribs as artificial roughness elements on the absorber plate. The range of parameters considered for the present investigation; Reynolds number (Re) 2000-14,000, relative roughness pitch (p/e) 3-8 and a fixed value of relative roughness height (e/D) of 0.030. The effective efficiency has been computed based on the experimentally determined values for the range of parameters considered. Further an attempt has also been made to optimize the thermal efficiency for the same system under similar conditions by Taguchi method. (author)

  5. Analysis of solar air-conditioning systems and their integration in buildings

    OpenAIRE

    Thomas, Sébastien

    2013-01-01

    Due to economical and environmental concerns, the energy e fficiency of buildings nowadays has proven to play an increasingly important role. To satisfy the occupants comfort, the cooling of buildings generally involves a considerable consumption of electricity. Solar radiation, which is a free and renewable resource, is linked to the cooling needs of buildings. This work consists in the evaluation, from an energy-saving and economical point of view, of a potential use of solar energy for ...

  6. Air

    International Nuclear Information System (INIS)

    In recent years several regulations and standards for air quality and limits for air pollution were issued or are in preparation by the European Union, which have severe influence on the environmental monitoring and legislation in Austria. This chapter of the environmental control report of Austria gives an overview about the legal situation of air pollution control in the European Union and in specific the legal situation in Austria. It gives a comprehensive inventory of air pollution measurements for the whole area of Austria of total suspended particulates, ozone, volatile organic compounds, nitrogen oxides, sulfur dioxide, carbon monoxide, heavy metals, benzene, dioxin, polycyclic aromatic hydrocarbons and eutrophication. For each of these pollutants the measured emission values throughout Austria are given in tables and geographical charts, the environmental impact is discussed, statistical data and time series of the emission sources are given and legal regulations and measures for an effective environmental pollution control are discussed. In particular the impact of fossil-fuel power plants on the air pollution is analyzed. (a.n.)

  7. Sorption-assisted solar air conditioning system in a factory building in Singapore. First operating experience; Solare sorptionsgestuetzte Klimatisierung eines Fabrikgebaeudes in Singapur. Erste Betriebserfahrungen

    Energy Technology Data Exchange (ETDEWEB)

    Hublitz, A.; Laevemann, E. [Bayerisches Zentrum fuer Angewandte Energieforschung e.V. (ZAE Bayern), Garching (Germany). Abt. Technik fuer Energiesysteme und erneuerbare Energien; Pelzer, M. [L-DCS Technology GmbH, Ismaning (Germany)

    2006-07-01

    In the last ten years, ZAE Bayern has been developing an ultra low-flow absorber, which enables efficient energy storage within the liquid desiccant. This technology is commercially available through L-DCS Technology GmbH, founded in 2003. In the current demonstration project L-DCS Technology supplied a liquid desiccant air dehumidification system (11,000 m{sup 3}/h) for a factory unit in Singapore, owned by JTC Corporation. A 550 m{sup 2} flat plate solar collector array drives the desiccant regeneration and 12 m{sup 3} desiccant energy storage covers the difference between the energy need for absorption and the energy supply for regeneration. First operational tests in February 06 showed acceptable absorber performance and energy storage capacity. (orig.)

  8. Heat transfer and friction factor characteristics of rectangular channel solar air heater duct having protrusions as roughness element

    Directory of Open Access Journals (Sweden)

    Maneesh Kaushal, Varun

    2012-01-01

    Full Text Available An experimental investigation has been carried out to see the effect of roughness element on heat transfer and friction factor on the absorber plate of the solar air heater. The roughness provided is in the form of protrusions which are arranged in an arc pattern. This paper presents an investigation to study the effect of protruded geometry on heat transfer coefficient and friction factor in an artificially roughened solar air heater duct. The pair of protrusion geometry arc angle (α of 45o is mounted on the test section of duct to create a longitudinal flow through test section. Measurements are carried out for rectangular duct which has aspect ratio (W/H of 11, relative roughness pitch (P/e in the range of 12-24, relative roughness height (e/D of 0.03, ratio of height of protrusion to print diameter (d of 0.3° and Reynolds number (Re ranges from 3600-18100.The results obtained for various relative roughness pitch (P/e has also been compared with smooth one. And on comparison to smooth duct, the roughened duct enhances the heat transfer and friction factor by 2.96 and 2.73 times.

  9. Heat transfer and friction factor characteristics of rectangular channel solar air heater duct having protrusions as roughness element

    Energy Technology Data Exchange (ETDEWEB)

    Kaushal, Maneesh; Varun [Department of Mechanical Engineering, National Institute of Technology Hamirpur (HP)-177005 (India)

    2012-07-01

    An experimental investigation has been carried out to see the effect of roughness element on heat transfer and friction factor on the absorber plate of the solar air heater. The roughness provided is in the form of protrusions which are arranged in an arc pattern. This paper presents an investigation to study the effect of protruded geometry on heat transfer coefficient and friction factor in an artificially roughened solar air heater duct. The pair of protrusion geometry arc angle (a) of 45° is mounted on the test section of duct to create a longitudinal flow through test section. Measurements are carried out for rectangular duct which has aspect ratio (W/H) of 11, relative roughness pitch (P/e) in the range of 12-24, relative roughness height (e/D) of 0.03, ratio of height of protrusion to print diameter (d) of 0.3° and Reynolds number (Re) ranges from 3600-18100.The results obtained for various relative roughness pitch (P/e) has also been compared with smooth one. And on comparison to smooth duct, the roughened duct enhances the heat transfer and friction factor by 2.96 and 2.73 times.

  10. The effect of fan speed control system on the inlet air temperature uniformity in a solar dryer

    Directory of Open Access Journals (Sweden)

    S. F Mousavi

    2015-09-01

    Full Text Available Introduction: Drying process of agricultural products, fruits and vegetables are highly energy demanding and hence are the most expensive postharvest operation. Nowadays, the application of control systems in different area of science and engineering plays a key role and is considered as the important and inseparable parts of any industrial process. The review of literature indicates that enormous efforts have been donefor the intelligent control of solar driers and in this regard some simulation models are used through computer programming. However, because of the effect of air velocity on the inlet air temperature in dryers, efforts have been made to control the fan speed based ont he temperature of the absorber plate in this study, and the behavior of this system was compared with an ordinary dryer without such a control system. Materials and methods: In this study, acabinet type solar dryer with forced convection and 5kg capacity of fresh herbs was used. The dryer was equipped with a fan in the outlet chamber (the chimney for creating air flow through the dryer. For the purpose of research methods and automatic control of fan speed and for adjusting the temperature of the drying inlet air, a control system consisting of a series of temperature and humidity sensors and a microcontroller was designed. To evaluatethe effect of the system with fan speed control on the uniformity of air temperature in the drying chamber and hence the trend of drying process in the solar dryer, the dryer has been used with two different modes: with and without the control of fan speed, each in twodays (to minimize the errors of almost the same ambient temperature. The ambient air temperature during the four days of experiments was obtained from the regional Meteorological Office. Some fresh mint plants (Mentha longifolia directly harvested from the farm in the morning of the experiment days were used as the drying materials. Each experimental run continued for 9

  11. Average Air Temperature Inside a Room With a Semitransparent Wall With a Solar Control Film: Effect of The Emissivity

    Directory of Open Access Journals (Sweden)

    J. Xamán

    2012-06-01

    Full Text Available In this paper a theoretical study on conjugated heat transfer (natural convection, radiation and conduction in a squareroom (cavity with turbulent flow is presented, taking into account variation on the opaque wall emissivity. The room isformed by an isothermal vertical wall, two adiabatic horizontal walls and a semitransparent wall with and without acontrol solar radiation film. The governing equations for turbulent flow in 2D were solved using a finite volumeformulation and k- turbulent model. Results for an isothermal wall at 21°C and an external temperature of 35°C arepresented. The size of the room is 4.0 m length and height and the solar radiation falling directly on thesemitransparent wall was 750 W/m2 (AM2. The emissivity of the opaque walls was varied between 0.1 ≤ * ≤ 1.0.Results show that, based on the air average temperature and the effective heat flux inside the room, the solar controlfilm under study was advantageous for energy saving purposes, for emissivity values of * ≤ 0.46. A correlation onthis system for the heat transfer as a function of the emissivities was determined.

  12. Impact of Solar Control PVB Glass on Vehicle Interior Temperatures, Air-Conditioning Capacity, Fuel Consumption, and Vehicle Range

    Energy Technology Data Exchange (ETDEWEB)

    Rugh, J.; Chaney, L.; Venson, T.; Ramroth, L.; Rose, M.

    2013-04-01

    The objective of the study was to assess the impact of Saflex1 S-series Solar Control PVB (polyvinyl butyral) configurations on conventional vehicle fuel economy and electric vehicle (EV) range. The approach included outdoor vehicle thermal soak testing, RadTherm cool-down analysis, and vehicle simulations. Thermal soak tests were conducted at the National Renewable Energy Laboratory's Vehicle Testing and Integration Facility in Golden, Colorado. The test results quantified interior temperature reductions and were used to generate initial conditions for the RadTherm cool-down analysis. The RadTherm model determined the potential reduction in air-conditioning (A/C) capacity, which was used to calculate the A/C load for the vehicle simulations. The vehicle simulation tool identified the potential reduction in fuel consumption or improvement in EV range between a baseline and modified configurations for the city and highway drive cycles. The thermal analysis determined a potential 4.0% reduction in A/C power for the Saflex Solar PVB solar control configuration. The reduction in A/C power improved the vehicle range of EVs and fuel economy of conventional vehicles and plug-in hybrid electric vehicles.

  13. Analysis of the influence of solar activity and atmospheric factors on 7Be air concentration by seasonal-trend decomposition

    Science.gov (United States)

    Bas, M. C.; Ortiz, J.; Ballesteros, L.; Martorell, S.

    2016-11-01

    7Be air concentrations were measured at the Universitat Politècnica de Valencia campus (in the east of Spain) during the period 2007-2014. The mean values of monthly 7Be concentrations ranged from 2.65 to 8.11 mBq/m3, showing significant intra and interannual variability. A seasonal-trend decomposition methodology was applied to identify the trend-cycle, seasonal and irregular components of the 7Be time series. The decomposition model makes it possible to estimate the influence of solar activity and atmospheric factors on the independent components, in order to find the different sources of 7Be variability. The results show that solar activity is a factor with a high inverse influence on the trend-cycle pattern of 7Be variability. Solar radiation, temperature and relative humidity are positive influential factors on the seasonal 7Be variation with a regular pattern over the years. Finally, the irregular component presents a significant negative correlation with precipitation and wind speed parameters, which have an irregular behavior over the years and seasons.

  14. Energy performance of solar-assisted liquid desiccant air-conditioning system for commercial building in main climate zones

    International Nuclear Information System (INIS)

    Highlights: • Simulation of solar liquid desiccant AC system in four climate regions was conducted. • System performance was determined by relationship of sensible and latent cooling load. • For humid area, saving amount is large by handling latent load with solar energy. • For dry area, electricity saving rate is considerable due to the high COP of chillers. • For buildings with mild SHR, the system performance was not as good as others. - Abstract: Liquid desiccant air-conditioning (LDAC) system, which consists of a liquid desiccant ventilation system for dehumidification and an air-handling unit for cooling, has become a promising alternative for conventional technology. To evaluate its feasibility and applicability, the simulation of solar-assisted LDAC (SLDAC) in commercial buildings in five cities of four main climate regions were conducted, including Singapore in Tropical, Houston and Beijing in Temperate, Boulder in Arid and Los Angeles in Mediterranean. Results showed that the system’s performance was seriously affected by the ratios of building’s sensible and latent cooling load. For buildings located in humid areas with low sensible-total heat ratio (SHR), the electricity energy reduction of SLDAC was high, about 450 MW h in Houston and Singapore, which accounted for 40% of the total energy consumption in cooling seasons. The cost payback period was as short as approximately 7 years. The main reason is that the energy required for handling the moisture could be saved by liquid desiccant dehumidification, and the regeneration heat could be covered by solar collectors. For buildings in dry climate with high SHR, the total cooling load was low, but up to 45% electricity of AC system could be saved in Boulder because the chiller COP could be significantly improved during more than 70% operation time. The cost payback period was around 22 years, which was acceptable. However, for the buildings with mild SHR, such as those in Beijing and Los

  15. Analysis of thermal and electrical performance of a hybrid (PV/T) air based solar collector for Iraq

    International Nuclear Information System (INIS)

    Highlights: ► An improved model is developed for single pass glazed PV/T collector. ► We examined the influence of different parameters. ► A summer day has better heating with lower overall efficiency compared with a winter day. -- Abstract: The electrical and thermal performance of a typical single pass hybrid photovoltaic/thermal (PV/T) air collector is modeled, simulated and analyzed for two selected case studies in Iraq. An improved mathematical thermo-electrical model is derived in terms of design, operating and climatic parameters of the hybrid solar collector to evaluate its important characteristics: collector flow and heat removal factors, PV maximum power point and its temperature coefficient, and overall power and efficiency. Unlike previous PV/T thermal models, the present model is obtained with some additions and corrections in radiation and convection heat coefficients for the top loss and for the air duct with more applicable sky temperature correlation. The well-known 5-parameter electrical model of PV module is solved using improved boundary conditions and translation equations for better convergence and accuracy. The voltage temperature coefficient of the PV module is included in the boundary conditions for convergence stability. The module parameters are taken to be dependent on solar radiation and PV cell temperature for improved accuracy. A Matlab computer simulation program is developed to solve the thermo-electrical model. The developed model is verified with previously published experimental results and theoretical simulations; it is proved to be most accurate in respect to percentage errors and correlation coefficients. Different parameters of the PV/T collector such as cell and air temperatures, thermal gain, PV current and voltage, and fill factor have been investigated. The results identified the effects of most important operating conditions such as sky, inlet and cell temperatures, air flow rate and incident solar radiation on

  16. Air-processed organic tandem solar cells on glass: toward competitive operating lifetimes

    DEFF Research Database (Denmark)

    Adams, Jens; Spyropoulos, George D.; Salvador, Michael;

    2015-01-01

    for long operating lifetimes consists of periodic UV light treatment. These results suggest that new material approaches towards UV-resilient active and interfacial layers may enable efficient organic tandem solar cells with lifetimes competitive with traditional inorganic photovoltaics.......Photovoltaic devices based on organic semiconductors (OPVs) hold great promise as a cost-effective renewable energy platform because they can be processed from solution and deposited on flexible plastics using roll-to-roll processing. Despite important progress and reported power conversion...... efficiencies of more than 10% the rather limited stability of this type of devices raises concerns towards future commercialization. The tandem concept allows for both absorbing a broader range of the solar spectrum and reducing thermalization losses. We designed an organic tandem solar cell with an inverted...

  17. Shelf life stability comparison in air for solution processed pristine PDPP3T polymer and doped spiro-OMeTAD as hole transport layer for perovskite solar cell

    Directory of Open Access Journals (Sweden)

    Ashish Dubey

    2016-06-01

    Full Text Available This data in brief includes forward and reverse scanned current density–voltage (J–V characteristics of perovskite solar cells with PDPP3T and spiro-OMeTAD as HTL, stability testing conditions of perovskite solar cell shelf life in air for both PDPP3T and spiro-OMeTAD as HTL as per the description in Ref. [1], and individual J–V performance parameters acquired with increasing time exposed in ambient air are shown for both type of devices using PDPP3T and spiro-OMeTAD as HTL. The data collected in this study compares the device stability with time for both PDPP3T and spiro-OMeTAD based perovskite solar cells and is directly related to our research article “solution processed pristine PDPP3T polymer as hole transport layer for efficient perovskite solar cells with slower degradation” [2].

  18. Design, fabrication, and characterization of multifunctional wings to harvest solar energy in flapping wing air vehicles

    Science.gov (United States)

    Perez-Rosado, Ariel; Gehlhar, Rachel D.; Nolen, Savannah; Gupta, Satyandra K.; Bruck, Hugh A.

    2015-06-01

    Currently, flapping wing unmanned aerial vehicles (a.k.a., ornithopters or robotic birds) sustain very short duration flight due to limited on-board energy storage capacity. Therefore, energy harvesting elements, such as flexible solar cells, need to be used as materials in critical components, such as wing structures, to increase operational performance. In this paper, we describe a layered fabrication method that was developed for realizing multifunctional composite wings for a unique robotic bird we developed, known as Robo Raven, by creating compliant wing structure from flexible solar cells. The deformed wing shape and aerodynamic lift/thrust loads were characterized throughout the flapping cycle to understand wing mechanics. A multifunctional performance analysis was developed to understand how integration of solar cells into the wings influences flight performance under two different operating conditions: (1) directly powering wings to increase operation time, and (2) recharging batteries to eliminate need for external charging sources. The experimental data is then used in the analysis to identify a performance index for assessing benefits of multifunctional compliant wing structures. The resulting platform, Robo Raven III, was the first demonstration of a robotic bird that flew using energy harvested from solar cells. We developed three different versions of the wing design to validate the multifunctional performance analysis. It was also determined that residual thrust correlated to shear deformation of the wing induced by torsional twist, while biaxial strain related to change in aerodynamic shape correlated to lift. It was also found that shear deformation of the solar cells induced changes in power output directly correlating to thrust generation associated with torsional deformation. Thus, it was determined that multifunctional solar cell wings may be capable of three functions: (1) lightweight and flexible structure to generate aerodynamic forces, (2

  19. Review paper on solar-powered air-conditioning through adsorption route

    Energy Technology Data Exchange (ETDEWEB)

    Choudhury, B.; Chatterjee, P.K. [Thermal Engineering Group, Central Mechanical Engineering Research Institute, Durgapur 713209 (India); Sarkar, J.P. [Chemical Engineering Department, National Institute of Technology, Durgapur 713209 (India)

    2010-10-15

    Solar-power based sorption refrigeration systems do not suffer from the problem of greenhouse gas emission and release of ozone layer depleting substances as in the case of conventional vapour compression refrigeration system. Absorption based systems are already commercially available while adsorption based systems are still in research and development stage. Progress and development of solar-powered adsorption cooling systems have been described in this paper. Factors preventing commercialization of this system have been discussed in detail. The state of the ongoing research, to make the system more efficient and cost effective, has been presented. (author)

  20. A simple nanostructured polymer/ZnO hybrid solar cell - preparation and operation in air

    OpenAIRE

    Krebs, Frederik C.; Thomann, Yi; Thomann, Ralf; ANDREASEN, Jens Wenzel

    2008-01-01

    A detailed description is given of the preparation of a polymer solar cell and its characterization. The solar cell can be prepared entirely in the ambient atmosphere by solution processing without the use of vacuum coating steps, and it can be operated in the ambient atmosphere with good operational stability under illumination (1000 W m(-2), AM1.5G, 72 +/- 2 degrees C, 35 +/- 5% relative humidity) for 100 h with a 20% loss in efficiency with respect to the initial performance. The dark stor...

  1. Solar panels as air Cherenkov detectors for extremely high energy cosmic rays

    International Nuclear Information System (INIS)

    Increasing interest towards the observation of the highest energy cosmic rays has motivated the development of new detection techniques. The properties of the Cherenkov photon pulse emitted in the atmosphere by these very rare particles indicate low-cost semiconductor detectors as good candidates for their optical read-out. The aim of this paper is to evaluate the viability of solar panels for this purpose. The experimental framework resulting from measurements performed with suitably-designed solar cells and large conventional photovoltaic areas is presented. A discussion on the obtained and achievable sensitivities follows

  2. Large scale deployment of polymer solar cells on land, on sea and in the air

    DEFF Research Database (Denmark)

    Espinosa Martinez, Nieves; Hösel, Markus; Jørgensen, Mikkel;

    2014-01-01

    for producing power and what the requirements are yet to be explored. We present here the installation of organic solar cell modules in different settings (terrestrial, marine and airborne). For the evaluation of these installations deployed at DTU, we have used the life cycle assessment tools, and calculated...

  3. Estimador de la carga (aire-GNC) aspirada por el motor de combustión interna duranrte condiciones transitorias de operación.

    OpenAIRE

    Barbieri, Andrés; Samat, David; Molina, Héctor

    2005-01-01

    Durante las operaciones transitorias de un motor, se requiere de una exacta relación aire combustible, a los efectos de optimizar la eficiencia y reducir las emisiones. Motores que de fabrica no están acondicionados para funcionar con gas y son transformados para funcionar con combustibles gaseosos (GNC) en los que se utiliza para su dosado mezcladores tipo Venturi, no brindan una respuesta satisfactoria para las condiciones antes expuestas. El presente trabajo describe y desarrol...

  4. Analytical performance investigation of parabolic trough solar collector with computed optimum air gap

    Directory of Open Access Journals (Sweden)

    Devander Kumar, Sudhir Kumar

    2015-01-01

    Full Text Available Parabolic trough collectors have a wide range of industrial as well as domestic applications. This study analytically investigates the performance of non-evacuated absorber tube with glass cover of parabolic trough collector (PTC in terms of overall heat loss from the absorber. The impact of different parameters such as diameter of absorber tube, mean temperature of absorber tube, wind velocity, emissivity of absorber and ambient temperature have been studied and find the optimum value of air gap. The optimum value of air gap has been computed considering one-dimensional steady state model, where heat loss due to convection plus radiation is equal to heat loss due to conduction plus radiation from absorber tube to glass cover under steady state. Optimum air gap is found to be approximately 7mm and 8 mm for an absorber tube of diameter in range of 1.2-3.18cm and 4.5-7.62cm, respectively. Corresponding to optimum air gap, minimum overall heat loss has been observed. Overall heat loss increases with increase in absorber temperature, wind velocity and emissivity of absorber, whereas decreases with increase in air temperature for different absorber tube diameters. Absorber tube with diameters in the range of 3.18-4.5cm gives better performance. From the obtained data, correlations have been developed, which can be further utilized for designing the PTC system for getting desired output.

  5. High-Temperature Thermal Storage System for Solar Tower Power Plants with Open-Volumetric Air Receiver Simulation and Energy Balancing of a Discretized Model

    OpenAIRE

    Kronhardt, Valentina; Alexopoulos, Spiros; Reißel, Martin; Sattler, Johannes; Hoffschmidt, Bernhard; Hänel, Matthias; Doerbeck, Till

    2013-01-01

    This paper describes the modeling of a high-temperature storage system for an existing solar tower power plant with open volumetric receiver technology, which uses air as heat transfer medium (HTF). The storage system model has been developed in the simulation environment Matlab/Simulink®. The storage type under investigation is a packed bed thermal energy storage system which has the characteristics of a regenerator. Thermal energy can be stored and discharged as required via the HTF air. ...

  6. Artificial neural network analysis of liquid desiccant dehumidifier performance in a solar hybrid air-conditioning system

    International Nuclear Information System (INIS)

    A new solar hybrid liquid desiccant air conditioning system has been tested and simulated to investigate the technical feasibility of cooling systems for greenhouse applications using weather data for Malaysia. In this paper, experimental tests are carried out to investigate the performance of a counter flow dehumidifier using lithium chloride (LiCl) solution as the desiccant. A single and multilayer artificial neural network is used to predict the performance of the dehumidifier. Five parameters are used as inputs to the ANN, namely: air and desiccant flow rates, air inlet humidity ratio, and air and desiccant inlet temperatures. The outputs of the ANN are the temperature, humidity ratio, moisture removal rate, and the effectiveness. ANN predictions for these parameters are compared with the experimental values. The results show that the optimum testing model for moisture removal rate in the dehumidifier was the 5-5-5-1 structure with R2 = 0.91, whereas the optimum testing model for effectiveness was the 5-11-11-1 structure with R2 = 0.79. The maximum temperature and humidity ratio difference between the ANN model and experimental are 1.2 °C and 1.9 g/kg, respectively. -- Highlights: • Experimental tests are carried out to investigate the performance of a counter flow dehumidifier. • Single and multilayer artificial neural network used to predict the performance of dehumidifier. • Outputs of the ANN are the temperature, humidity ratio, moisture removal rate, and effectiveness. • The results show that the optimum testing model for MRR was the 5-5-5-1 structure with R2 = 0.91. • The optimum testing model for effectiveness was the 5-11-11-1 structure with R2 = 0.79

  7. A vacuum tube vee-trough collector for solar heating and air conditioning applications

    Science.gov (United States)

    Selcuk, M. K.

    1978-01-01

    An analysis is conducted of the performance of a vee-trough vacuum tube collector proposed for use in solar heating and cooling applications. The vee-trough reflector is a triangular sectioned, flat surfaced reflector, whose axis is laid in the East-West direction. A vacuum tube receiver placed at the bottom of the vee-trough collects solar heat most efficiently since convection is completely eliminated. Radiation losses are reduced by use of selective coatings on the absorber. Owing to its high temperature capabilities (300-400 F), the proposed scheme could also be used for power generation applications in combination with an organic Rankine conversion system. It is especially recommended for unattended pumping stations since the reflectors only require reversal once every six months.

  8. 整体式太阳能空气集热器传热性能分析%Integral Solar Air Collector of the Thermal Performance Analysis

    Institute of Scientific and Technical Information of China (English)

    吴国玉; 胡明辅; 袁江; 毕二朋

    2012-01-01

    A physical mathematical model based on steady -state assumption is developed to study the heat transfer characteristics in the integral solar air collector. Through the CFD software is applied to numerical simulation, the effect of various parameters such as the inlet air velocity, air temperature and the intensity of solar radiation of the air heater are analyzed. It is discovered that thermal efficiency increases wilh increasing air velocity and decreasing temperature of inlet air, on which the solar radiation intensity have little influence.%研究了整体式太阳能空气集热器的传热性能,建立了稳态假设下的热量传递物理数学模型;通过CFD软件计算,分析了进口空气流速、空气温度、太阳辐照强度对集热器传热性能的影响;计算结果表明:集热器的集热效率随工质流速的增大而增大、随进口温度的升高而下降、随太阳辐照度的波动很小,受太阳辐射强度的影响不大.

  9. IEA SHC Task 38 'Solar air-conditioning and refrigeration'. Danish participation 2007-2010; IEA SHC Task 38 'Solar air-conditioning and refrigeration'. Dansk deltagelse 2007-2010

    Energy Technology Data Exchange (ETDEWEB)

    Ellehauge, K. (Ellehauge og Kildemoes, Aarhus (Denmark)); Muenster, E. (PlanEnergi, Skoerping (Denmark)); Reinholdt, L. (Teknologisk Institut, Aarhus (Denmark)); Minds, S. (AC-Sun Aps, Horsens (Denmark))

    2011-03-15

    IEA SHC Task 38 'Solar Air-Conditioning and Refrigeration' ran from October 2006 to December 2010. Denmark was represented in the task from January 2007 to December 2010. The aim of the task was to encourage use of solar powered refrigeration and air conditioning systems in particular at residential, commercial and industrial sectors. Furthermore, the aim was to contribute to new research and development activities on new systems and concepts. Solar cooling is an energy efficient way to cool buildings, which can also be used in Denmark as there is a high correlation between solar radiation and the need for air conditioning. Part of the Danish team has also been the company AC Sun which in the period has worked with developing a new and revolutionary thermo-cooling technology. IEA SHC Task 38 Solar Air-Conditioning and Refrigeration was divided into 4 subtask: 1) Subtask A: Pre-engineered systems for residential and small commercial applications 2) Subtask B: Custom-made systems for large non-residential buildings and industrial applications 3) Subtask C: Modelling and fundamental analysis 4) Subtask D: Market transfer activities. The Danish participation consisted of: 1) Ellehauge and Kildemoes (Klaus Ellehauge), project management and overall information. Participated in the subtask A and C and D. 2) AC-Sun (Soeren Minds) participated in subtask A, C and D. 3) PlanEnergi (Ebbe Muenster) participated in subtask B and C. 4) Technological Institute (Lars Reinholdt) participated in subtask A, B and C. The main findings of the task are given in the new handbook that will be published in summer 2011. This report summarises some of the results in Danish and in particular the Danish effort. The Danish project group has provided input to the international reports of the task. A number of the materials prepared by the project are attached as annexes. PlanEnergi was involved in analysis of measurements of the absorption system of 105 kW established year 2007 in

  10. Solar thermochemical production of ammonia from water, air and sunlight: Thermodynamic and economic analyses

    International Nuclear Information System (INIS)

    Ammonia is an important input into agriculture and is used widely as base chemical for the chemical industry. It has recently been proposed as a sustainable transportation fuel and convenient one-way hydrogen carrier. Employing typical meteorological data for Palmdale, CA, solar energy is considered here as an inexpensive and renewable energy alternative in the synthesis of NH3 at ambient pressure and without natural gas. Thermodynamic process analysis shows that a molybdenum-based solar thermochemical NH3 production cycle, conducted at or below 1500 K, combined with solar thermochemical H2 production from water may operate at a net-efficiency ranging from 23 to 30% (lower heating value of NH3 relative to the total energy input). Net present value optimization indicates ecologically and economically sustainable NH3 synthesis at above about 160 tons NH3 per day, dependent primarily on heliostat costs (varied between 90 and 164 dollars/m2), NH3 yields (ranging from 13.9 mol% to stoichiometric conversion of fixed and reduced nitrogen to NH3), and the NH3 sales price. Economically feasible production at an optimum plant capacity near 900 tons NH3 per day is shown at relative conservative technical assumptions and at a reasonable NH3 sales price of about 534 ± 28 dollars per ton NH3. -- Highlights: ► Conceptual reactant and process improvements of solar-driven NH3 synthesis at 1 bar. ► Thermodynamic underpinnings of a Molybdenum reactant. ► Process analysis determining energy and materials requirements and the net-efficiency. ► Net present value analysis accounting for yield, investment, and sales price variations.

  11. Solar panels as air Cherenkov detectors for extremely high energy cosmic rays

    OpenAIRE

    Cecchini, S.; D'Antone, I; Esposti, L. Degli; Giacomelli, G.; Guerra, M; Lax, I; Mandrioli, G.; Parretta, A.; Sarno, A.; Schioppo, R.; Sorel, M.; Spurio, M.

    2000-01-01

    Increasing interest towards the observation of the highest energy cosmic rays has motivated the development of new detection techniques. The properties of the Cherenkov photon pulse emitted in the atmosphere by these very rare particles indicate low-cost semiconductor detectors as good candidates for their optical read-out. The aim of this paper is to evaluate the viability of solar panels for this purpose. The experimental framework resulting from measurements performed with suitably-designe...

  12. A simple nanostructured polymer/ZnO hybrid solar cell-preparation and operation in air

    Energy Technology Data Exchange (ETDEWEB)

    Krebs, Frederik C; Andreasen, Jens W [Risoe National Laboratory for Sustainable Energy, Technical University of Denmark, Frederiksborgvej 399, DK-4000 Roskilde (Denmark); Thomann, Yi; Thomann, Ralf [Freiburger Materialforschungszentrum, University of Freiburg, Stefan Meier Strasse 21, 79104 Freiburg (Germany)], E-mail: frederik.krebs@risoe.dk

    2008-10-22

    A detailed description is given of the preparation of a polymer solar cell and its characterization. The solar cell can be prepared entirely in the ambient atmosphere by solution processing without the use of vacuum coating steps, and it can be operated in the ambient atmosphere with good operational stability under illumination (1000 W m{sup -2}, AM1.5G, 72 {+-} 2 deg. C, 35 {+-} 5% relative humidity) for 100 h with a 20% loss in efficiency with respect to the initial performance. The dark storability (darkness, 25 deg. C, 35 {+-} 5% relative humidity) has been shown to exceed six months without notable loss in efficiency. The devices do not require any form of encapsulation to gain stability, while a barrier for mechanical protection may be useful. The devices are based on soluble zinc oxide nanoparticles mixed with the thermocleavable conjugated polymer poly-(3-(2-methylhexan-2-yl)-oxy-carbonyldithiophene) (P3MHOCT), which through a thermal treatment is converted to the insoluble form poly(3-carboxydithiophene) (P3CT) that generally gives stable polymer solar cells. The devices employed a solution based silver back electrode. One advantage is that preparation of the devices is very simple and can be carried out by hand under ambient conditions, requiring only a hot plate that can reach a temperature of 210 deg. C, and preferably also a spincoater. This type of device is thus excellently suited for teaching and demonstration purposes provided that the materials are at hand.

  13. A simple nanostructured polymer/ZnO hybrid solar cell—preparation and operation in air

    Science.gov (United States)

    Krebs, Frederik C.; Thomann, Yi; Thomann, Ralf; Andreasen, Jens W.

    2008-10-01

    A detailed description is given of the preparation of a polymer solar cell and its characterization. The solar cell can be prepared entirely in the ambient atmosphere by solution processing without the use of vacuum coating steps, and it can be operated in the ambient atmosphere with good operational stability under illumination (1000 W m-2, AM1.5G, 72 ± 2 °C, 35 ± 5% relative humidity) for 100 h with a 20% loss in efficiency with respect to the initial performance. The dark storability (darkness, 25 °C, 35 ± 5% relative humidity) has been shown to exceed six months without notable loss in efficiency. The devices do not require any form of encapsulation to gain stability, while a barrier for mechanical protection may be useful. The devices are based on soluble zinc oxide nanoparticles mixed with the thermocleavable conjugated polymer poly-(3-(2-methylhexan-2-yl)-oxy-carbonyldithiophene) (P3MHOCT), which through a thermal treatment is converted to the insoluble form poly(3-carboxydithiophene) (P3CT) that generally gives stable polymer solar cells. The devices employed a solution based silver back electrode. One advantage is that preparation of the devices is very simple and can be carried out by hand under ambient conditions, requiring only a hot plate that can reach a temperature of 210 °C, and preferably also a spincoater. This type of device is thus excellently suited for teaching and demonstration purposes provided that the materials are at hand.

  14. Optimization of thermal performance of a smooth flat-plate solar air heater using teaching–learning-based optimization algorithm

    Directory of Open Access Journals (Sweden)

    R. Venkata Rao

    2015-12-01

    Full Text Available This paper presents the performance of teaching–learning-based optimization (TLBO algorithm to obtain the optimum set of design and operating parameters for a smooth flat plate solar air heater (SFPSAH. The TLBO algorithm is a recently proposed population-based algorithm, which simulates the teaching–learning process of the classroom. Maximization of thermal efficiency is considered as an objective function for the thermal performance of SFPSAH. The number of glass plates, irradiance, and the Reynolds number are considered as the design parameters and wind velocity, tilt angle, ambient temperature, and emissivity of the plate are considered as the operating parameters to obtain the thermal performance of the SFPSAH using the TLBO algorithm. The computational results have shown that the TLBO algorithm is better or competitive to other optimization algorithms recently reported in the literature for the considered problem.

  15. Techno-economic analysis of a roof-integrated solar air heating system for drying fruit and vegetables

    Energy Technology Data Exchange (ETDEWEB)

    Sreekumar, A. [Dept. of Physics, Cochin University of Science and Technology, Kochi 682 022 (India)

    2010-11-15

    The solar air heater was 46 m{sup 2} and recorded a maximum temperature of 76.6 C. The dryer was loaded with 200 kg of fresh pineapple slices 5 mm thick. The initial moisture content of 82% was reduced to the desired level (<10%) within 8 h. The performance of the dryer was analyzed in detail by three methods namely annualized cost, present worth of annual savings, and present worth of cumulative savings. The cost of drying 1 kg pineapple worked out to Rs. 11 which was roughly half of that of an electric dryer. The payback period worked out to 0.54 year, much less than the estimated life of the system (20 years). (author)

  16. Collector Efficiency in Downward-Type Double-Pass Solar Air Heaters with Attached Fins and Operated by External Recycle

    Directory of Open Access Journals (Sweden)

    Chii-Dong Ho

    2012-07-01

    Full Text Available The collector efficiency in a downward-type double-pass external-recycle solar air heater with fins attached on the absorbing plate has been investigated theoretically. Considerable improvement in collector efficiency is obtainable if the collector is equipped with fins and the operation is carried out with an external recycle. Due to the recycling, the desirable effect of increasing the heat transfer coefficient compensates for the undesirable effect of decreasing the driving force (temperature difference of heat transfer, while the attached fins provide an enlarged heat transfer area. The order of performances in the devices of same size is: double pass with recycle and fins > double pass with recycle but without fins > single pass without recycle and fins.

  17. Performance evaluation of roughened solar air heater having M-shaped as roughness geometry on the absorber plate

    Energy Technology Data Exchange (ETDEWEB)

    Chauhan, Manish Kumar [Mechanical and Industrial Engineering Department, IIT Roorkee, (U.K.) – 247667 (India); Varun; Chaudhary, Sachin [Mechanical Engineering Department, NIT Hamirpur, (H.P.) – 177005 (India)

    2012-07-01

    As thermal efficiency of conventional solar air heater is low, best way is to enhance its thermal efficiency is make the flow turbulent. This can be achieved by using the artificial roughness on underside of absorber plate. An attempt has been made to enhance its thermal as well as thermohydraulic performance by providing roughness elements. An experimental investigation has been carried out on M-shaped ribs having circular cross section on absorber plate. The duct is having an aspect ratio of (W/H) 11.41, relative roughness height (e/D) 0.033-0.077, relative roughness pitch (P/e) 12.5-75 and angle of attack (a) 30-60°. The range for Reynolds number has been considered to be 3000-22000. The best result of thermal and thermohydraulic performance has been observed at (e/D) 0.077, (P/e) 25 and (a) 60°.

  18. Perspective: Maintaining surface-phase purity is key to efficient open air fabricated cuprous oxide solar cells

    Directory of Open Access Journals (Sweden)

    Robert L. Z. Hoye

    2015-02-01

    Full Text Available Electrochemically deposited Cu2O solar cells are receiving growing attention owing to a recent doubling in efficiency. This was enabled by the controlled chemical environment used in depositing doped ZnO layers by atomic layer deposition, which is not well suited to large-scale industrial production. While open air fabrication with atmospheric pressure spatial atomic layer deposition overcomes this limitation, we find that this approach is limited by an inability to remove the detrimental CuO layer that forms on the Cu2O surface. Herein, we propose strategies for achieving efficiencies in atmospherically processed cells that are equivalent to the high values achieved in vacuum processed cells.

  19. Preliminary design review package on air flat plate collector for solar heating and cooling system

    Science.gov (United States)

    1977-01-01

    Guidelines to be used in the development and fabrication of a prototype air flat plate collector subsystem containing 320 square feet (10-4 ft x 8 ft panels) of collector area are presented. Topics discussed include: (1) verification plan; (2) thermal analysis; (3) safety hazard analysis; (4) drawing list; (5) special handling, installation and maintenance tools; (6) structural analysis; and (7) selected drawings.

  20. Efek Durasi Pencahayaan Pada Sistem HRAR Untuk Menurunkan Kandungan Minyak Solar Dalam Air Limbah

    OpenAIRE

    Dian Puspitasari; Agus Slamet; Joni Hermana

    2014-01-01

    Kandungan minyak di dalam air limbah industri perminyakan umumnya bersifat toksik terhadap mikroorganisme dan mengganggu proses pengolahan secara biologis. Sistem HRAR diperkirakan dapat mengatasi hambatan tersebut melalui proses fotosintesis untuk menghasilkan oksigen yang dibutuhkan mikroorganisme dalam mendegradasi senyawa hidrokarbon. Penelitian ini bertujuan mengkaji pengaruh perpanjangan waktu pencahayaan pada kemampuan HRAR dalam menurunkan kandungan minyak di dalam limbah. Variabel ya...

  1. US Air Force Space Weather Products Rapid Prototyping Efforts - Solar Radio Background/Burst Effects and Meteor Effects Products

    Science.gov (United States)

    Quigley, S.; Scro, K.

    2001-12-01

    The Space Vehicles Directorate of the Air Force Research Laboratory (AFRL/VSB) has joined efforts with the Technology Applications Division of the Space and Missile Systems Center (SMC Det 11/CIT) to rapidly transition space weather research into prototype, operational, system-impact products. These Rapid Prototyping Center (RPC) products are used to analyze, specify, and forecast the effects of the near-earth space environment on Department of Defense systems and communications. A summary of RPC activity is provided. Emphasis will be placed on current products under development, to include Solar Radio Background/Burst Effects (SoRBE) and Meteor Effects (ME) products. These will be added to real-time operations in the near future. SoRBE specifies the detrimental interference effects of background and event-level solar radio output on radar observations and satellite communications. ME will provide general meteor shower "nowcast" and forecast information, along with more specific meteor and meteor shower impact, radar clutter, and bolide (exploding meteor) effects. A brief overview of recently delivered products: Radar Auroral Clutter, Satellite Scintillation, HF Illumination, and GPS Single-Frequency Error Maps will also be provided.

  2. Cumulative ventilation air drying potential as an indication of dry mass content in wastewater sludge in a thin-layer solar drying facility

    Science.gov (United States)

    Krawczyk, Piotr

    2013-12-01

    Controlling low-temperature drying facilities which utilise nonprepared air is quite difficult, due to very large variability of ventilation air parameters - both in daily and seasonal cycles. The paper defines the concept of cumulative drying potential of ventilation air and presents experimental evidence that there is a relation between this parameter and condition of the dried matter (sewage sludge). Knowledge on current dry mass content in the dried matter (sewage sludge) provides new possibilities for controlling such systems. Experimental data analysed in the paper was collected in early 2012 during operation of a test solar drying facility in a sewage treatment plant in Błonie near Warsaw, Poland.

  3. Procedimiento para el diseño de un sistema de calentamiento solar-mixto de aire que utiliza agua como fluido de trabajo

    OpenAIRE

    Luis Francisco Boada E.; Carlos Alfonso Rodríguez A.; Luz Marina Salazar L.

    2011-01-01

    En este artículo se describe un sistema solar-mixto de calefacción de aire que incorpora colectores planos calentadores del agua, un tanque acumulador de calor y un dispositivo para el intercambio de calor agua-aire. Se presentan los ensayos que determinaron la disposición óptima del equipo para el intercambio de calor con flujo de agua por termosifón y el comportamiento térmico para diferentes flujos de aire, así como los ensayos para conocer el comportamiento del sistema de calentamiento so...

  4. A simple nanostructured polymer/ZnO hybrid solar cell-preparation and operation in air.

    Science.gov (United States)

    Krebs, Frederik C; Thomann, Yi; Thomann, Ralf; Andreasen, Jens W

    2008-10-22

    A detailed description is given of the preparation of a polymer solar cell and its characterization. The solar cell can be prepared entirely in the ambient atmosphere by solution processing without the use of vacuum coating steps, and it can be operated in the ambient atmosphere with good operational stability under illumination (1000 W m(-2), AM1.5G, 72 ± 2 °C, 35 ± 5% relative humidity) for 100 h with a 20% loss in efficiency with respect to the initial performance. The dark storability (darkness, 25 °C, 35 ± 5% relative humidity) has been shown to exceed six months without notable loss in efficiency. The devices do not require any form of encapsulation to gain stability, while a barrier for mechanical protection may be useful. The devices are based on soluble zinc oxide nanoparticles mixed with the thermocleavable conjugated polymer poly-(3-(2-methylhexan-2-yl)-oxy-carbonyldithiophene) (P3MHOCT), which through a thermal treatment is converted to the insoluble form poly(3-carboxydithiophene) (P3CT) that generally gives stable polymer solar cells. The devices employed a solution based silver back electrode. One advantage is that preparation of the devices is very simple and can be carried out by hand under ambient conditions, requiring only a hot plate that can reach a temperature of 210 °C, and preferably also a spincoater. This type of device is thus excellently suited for teaching and demonstration purposes provided that the materials are at hand. PMID:21832673

  5. Simulación matemática y optimización del secado de productos agropecuarios con aire natural y energía solar

    Directory of Open Access Journals (Sweden)

    Jorge H. Domínguez

    2011-11-01

    Full Text Available En este trabajo se discuten las principales características de los sistemas de secado de productos agropecuarios con aire natural y energía solar y se presenta un programa de computador con el cual es posible simular, simultáneamente, la variación meteorológica, el proceso de secado y el proceso de deterioración de productos agropecuarios y optimizar el diseño de sistemas de secado solar y natural. EI programa constituye una herramienta básica que forma parte de una metodología de trabajo desarrollada por los autores para el estudio y evaluación desde el punto de vista técnico del potencial de secado con aire natural y energía solar de regiones tropicales.

  6. Performance evaluation of a state-of-the-art solar air-heating system with auxiliary heat pump. Final report, 1 October 1978-30 September 1979

    Energy Technology Data Exchange (ETDEWEB)

    Karaki, S.; Brisbane, T.E.; Waterbury, S.S.; Lantz, T.G.

    1980-01-01

    The solar heating system in Solar House II, evaluated during the heating season of 1978-1979, consists of 57.9 m/sup 2/ of Solaron Series 3000 Collectors, 10.3 m/sup 3/ of pebble bed storage, domestic water preheating capability and a Carrier air-to-air heat pump as an auxiliary heater. Although the control subsystem was specially constructed to facilitate experimental changes and data reduction, the balance of the solar system was assembled with off-the-shelf components. Descriptions of the building and the system, modes of system operation, the data acquisition system, data processing, and performance - thermal, collector, storage, and heat pump - are included. (MHR)

  7. Study on heat collector of the solar system utilizing outdoor air. Experimental results in cases of cold and warm regions; Gaiki donyushiki solar system no shunetsubu ni kansuru kenkyu. Kanreichi to ondanchi ni okeru shunetsu jikken to kosatsu

    Energy Technology Data Exchange (ETDEWEB)

    Komano, S.; Ebara, Y. [OM Solar Association, Shizuoka (Japan); Wada, H. [Wada Building Constructors Co. Ltd., Hokkaido (Japan)

    1996-10-27

    An experiment on heat collection was made in the heat collector of a solar system utilizing outdoor air in cold and warm regions. In this system, outdoor air is heated by the air circulation layer on the roof exposed to solar radiation. The heated air is supplied to the object space for heating and ventilation. In the experiment in a cold region, the heat collection characteristics can be adjusted by putting a baffle plate in the air duct according to the experiment of a glass heat collector. The heat collecting air layer on only the iron roof may leak or freeze in the region subject to coldness or heavy snowfall. Therefore, preheat forms the space of a garret, and the preheat temperature comparatively becomes low. The data in which the heat collection characteristics can be adjusted using only a glass heat collector is required corresponding to the regional situation. In the experiment in a warm region, an experiment was made inclusive of the preheat for which outdoor air is absorbed at the eaves. As a result, the heat collection characteristics of preheat were improved. Moreover, a heat collection temperature of about 60{degree}C was obtained on the heat collection surface including the preheat. 1 ref., 12 figs., 3 tabs.

  8. Development of a solar-powered residential air conditioner: Economic analysis

    Science.gov (United States)

    1975-01-01

    The results of investigations aimed at the development of cost models to be used in the economic assessment of Rankine-powered air conditioning systems for residential application are summarized. The rationale used in the development of the cost model was to: (1) collect cost data on complete systems and on the major equipment used in these systems; (2) reduce these data and establish relationships between cost and other engineering parameters such as weight, size, power level, etc; and (3) derive simple correlations from which cost-to-the-user can be calculated from performance requirements. The equipment considered in the survey included heat exchangers, fans, motors, and turbocompressors. This kind of hardware represents more than 2/3 of the total cost of conventional air conditioners.

  9. Choice of Domestic Air-Sourced Solar Photovoltaic Thermal Systems through the Operational Energy Cost Implications in Scotland

    Directory of Open Access Journals (Sweden)

    Masa Noguchi

    2013-03-01

    Full Text Available In Scotland, homebuilders are requested to take valiant efforts to meet the government’s ambition that all newly built homes should be carbon-neutral by 2016/17. In delivering net zero carbon homes, the application of renewable energy technologies, such as solar photovoltaic (PV power generating systems, is almost inevitable. Cost-effectiveness of emerging green technologies is a major factor that affects stakeholders’ housing design decision-making on whether or not the innovations can be applied in practical terms. Based on the United Kingdom (UK government’s Standard Assessment Procedure (SAP for energy rating of dwellings, this study conducted a comparative value assessment of 19 design alternatives set. The options also included ones that encompassed both electricity and heat generation potentials of PV applications—i.e., air-sourced PV thermal (PV/T systems. Based on the SAP simulation results, it concluded that operational energy use and cost, as well as carbon dioxide (CO2 emission levels, can drastically be reduced particularly when a PV/T system is combined with a low-energy and high-performance mechanical ventilation with heat recovery (MVHR system that can extract fresh air heated by PV. This study led to visualizing the cost-effectiveness of PV/T MVHR systems and identifying the economic value over 10 years at the interest rate of 10%, based on an assumption that the innovations are applied to Scottish homes today.

  10. Solvent Engineering for Ambient-Air-Processed, Phase-Stable CsPbI3 in Perovskite Solar Cells.

    Science.gov (United States)

    Luo, Paifeng; Xia, Wei; Zhou, Shengwen; Sun, Lin; Cheng, Jigui; Xu, Chenxi; Lu, Yingwei

    2016-09-15

    Inorganic CsPbI3 perovskite solar cells (PSCs) owning comparable photovoltaic performance and enhanced thermal stability compared to organic-inorganic hybrid perovskites have attracted enormous interest in the past year. However, it is still a challenge to stabilize the desired black α-CsPbI3 perovskites in ambient air for photovoltaic applications. Herein, sequential solvent engineering including the addition of hydroiodic acid (HI) and subsequent isopropanol (IPA) treatment for fabricating stable and working CsPbI3 PSCs is developed, and a novel low-temperature phase-transition route from new intermediate Cs4PbI6 to stable α-CsPbI3 is also released for the first time. As such, the as-prepared PSCs give a relatively high power conversion efficiency (PCE) of 4.13% (reverse scan), and the steady-state power output of 1.88% is confirmed for the selected cell with an initial PCE of 3.13%. To the best of our knowledge, this is the first demonstration of fabricating CsPbI3 inorganic PSCs under fully open-air conditions. PMID:27569604

  11. Analysis of fluid flow and heat transfer in a rib grit roughened surface solar air heater using CFD

    Energy Technology Data Exchange (ETDEWEB)

    Karmare, S.V. [Department of Mechanical Engineering, Government College Engineering, Karad 415 124, Maharashtra (India); Shivaji University, Kolhapur, Maharashtra (India); Tikekar, A.N. [Department of Mechanical Engineering, Walchand College of Engineering, Sangli (India); Shivaji University, Kolhapur, Maharashtra (India)

    2010-03-15

    This paper presents the study of fluid flow and heat transfer in a solar air heater by using Computational Fluid Dynamics (CFD) which reduces time and cost. Lower side of collector plate is made rough with metal ribs of circular, square and triangular cross-section, having 60 inclinations to the air flow. The grit rib elements are fixed on the surface in staggered manner to form defined grid. The system and operating parameters studied are: e/D{sub h} = 0.044, p/e = 17.5 and l/s = 1.72, for the Reynolds number range 3600-17,000. To validate CFD results, experimental investigations were carried out in the laboratory. It is found that experimental and CFD analysis results give the good agreement. The optimization of rib geometry and its angle of attack is also done. The square cross-section ribs with 58 angle of attack give maximum heat transfer. The percentage enhancement in the heat transfer for square plate over smooth surface is 30%. (author)

  12. Irreversibility Analysis of Non Isothermal Flat Plate Solar Collectors for Air Heating with a Dimensionless Model

    Directory of Open Access Journals (Sweden)

    Baritto-Loreto Miguel Leonardo

    2013-04-01

    Full Text Available En el presente trabajo, el modelo adimensional desarrollado y validado por Baritto y Bracamonte (2012 para describir el comportamiento térmico de colectores solares de placas planas sin cubierta transparente, se complementa con la ecuación adimensional de balance de entropía para un elemento diferencial de colector solar. El modelo se resuelve para un amplio rango de valores de relaciones de aspecto y número de flujo de masa. A partir de los resultados del modelo se desarrolla un análisis detallado de la influencia de estos parámetros sobre la distribución de irreversibilidades internas a lo largo del colector. Adicionalmente se estudia la influencia de estos parámetros sobre los números de generación de entropía por fricción viscosa, por transferencia de calor y total. Se encuentra que existen combinaciones de los parámetros antes mencionados, para los cuales, la operación del colector es termodinámicamente óptima para números de flujo de masa elevados.

  13. Thermal performance of solar air collector with slit-like perforations

    Institute of Scientific and Technical Information of China (English)

    李宪莉; 由世俊; 张欢; 尤占平

    2009-01-01

    To offer a potentially low-cost and high-efficiency option for once-through applications,the unglazed transpired solar collector was studied. The semi-empirical correlation of overall heat exchange effectivenessε for UTC with circular holes was proposed to verify whether it being fit for this kind of absorber with slit-like perforations. The results show that in certain parameters,the predicted values of ε are very close to measured values,and the root mean square difference in betweens about 0.10,so the modle is suitable. Based on experimental results,this kind of absorber is proved to be feasible,with highest value of ε,up to 0.81. In addition,with the increase of γ,overall heat exchange effectiveness ε will decrease,i.e.,the value of ε will decrease with the increase of suction velocity vs or the decrease of wind velocity uw. However,the actual value of solar radiation intensity G and ambient temperature T∞ have little influence on ε.

  14. Solar driven nitrous acid formation on building material surfaces containing titanium dioxide: A concern for air quality in urban areas?

    Science.gov (United States)

    Langridge, Justin M.; Gustafsson, R. Joel; Griffiths, Paul T.; Cox, R. Anthony; Lambert, Richard M.; Jones, Roderic L.

    The photoenhanced uptake of nitrogen dioxide (NO 2) to the surface of commercially available self-cleaning window glass has been studied under controlled laboratory conditions. This material is one of an array of modern building products which incorporate titanium dioxide (TiO 2) nanoparticles and are finding increasing use in populated urban areas. Amongst the principal drivers for the use of these materials is that they are thought to facilitate the irreversible removal of pollutants such as NO 2 and organic molecules from the atmosphere and thus act to remediate air quality. While it appears that TiO 2 materials do indeed remove organic molecules from built environments, in this study we show that the photoenhanced uptake of NO 2 to one example material, self-cleaning window glass, is in fact accompanied by the substantial formation (50-70%) of gaseous nitrous acid (HONO). This finding has direct and serious implications for the use of these materials in urban areas. Not only is HONO a harmful respiratory irritant, it is also readily photolysed by solar radiation leading to the formation of hydroxyl radicals (OH) together with the re-release of NO x as NO. The net effect of subsequent OH initiated chemistry can then be the further degradation of air quality through the formation of secondary pollutants such as ozone and VOC oxidation products. In summary, we suggest that a scientifically conceived technical strategy for air quality remediation based on this technology, while widely perceived as universally beneficial, could in fact have effects precisely opposite to those intended.

  15. Procedimiento para el diseño de un sistema de calentamiento solar-mixto de aire que utiliza agua como fluido de trabajo

    Directory of Open Access Journals (Sweden)

    Luis Francisco Boada E.

    2011-11-01

    Full Text Available En este artículo se describe un sistema solar-mixto de calefacción de aire que incorpora colectores planos calentadores del agua, un tanque acumulador de calor y un dispositivo para el intercambio de calor agua-aire. Se presentan los ensayos que determinaron la disposición óptima del equipo para el intercambio de calor con flujo de agua por termosifón y el comportamiento térmico para diferentes flujos de aire, así como los ensayos para conocer el comportamiento del sistema de calentamiento solar de agua. Finalmente, el diseño se efectúa mediante un programa de computador adaptado para tal fin.

  16. EXPERIMENTAL INVESTIGATION ON DESICCANT AIR-CONDITIONING SYSTEM ASSISTED BY SOLAR AIR COLLECTOR WITH VACUUM TUBE%真空管太阳集热器辅助除湿空调的实验研究

    Institute of Scientific and Technical Information of China (English)

    文玉良; 丁静

    2009-01-01

    参考国家标准太阳能热水系统测试方法真空管太阳集热器辅助除湿空调系统进行了测试研究,该太阳能吸附除湿空调系统将太阳能热利用技术有机的结合在一起,改善了室内空气品质,达到了安全通风的目的.实验结果表明真空管集热器对于较高温度的空气吸热效率较高,太阳能辅助除湿空调适用于广州这类夏天高温高湿的地区.%Experimental tests and analyses were conducted to investigate the desiccant air-condidtioning system assisted by solar air collector with vacuum tube consulting with GB,testing of solar water system.This system improved the inner air quality and ventiated safety accompanied with solar thermal technology.The results showed that solar collector with vacuum tube have a high efficiency while in higher temperature, and desiccant cooling systems is suitable to Guangdong which is hot and humidity.

  17. Modeling and numerical simulation of a novel solar-powered absorption air conditioning system driven by a bubble pump with energy storage

    Institute of Scientific and Technical Information of China (English)

    QIU Jia; LIANG Jian; CHEN GuangMing; DU RuXu

    2009-01-01

    This paper presents a novel solar-powered absorption air conditioning system driven by a bubble pump with energy storage. It solves the problem of unreliable solar energy supply by storing the working fluids and hence, functions 24 h per day. First, the working principles are described and the dynamic models for the primary energy storage components are developed. Then, the system is evaluated based on a numerical simulation. Based on the meteorological data of a typical day in a subtropical area, with the area of a solar collector being set at 19.15 m2, whilst the initial charging mass, mass fraction and temperature of the solution are respectively set at 379.5 kg, 54.16% and 34.5 ℃, it is found that the respective coefficients of performance (COP) of the air conditioning system and the en-tire system (including the solar panel) are 0.7771 and 0.4372. In particular, the energy storage density of the system is 206.69 MJ/m3 which is much greater than those of chilled water or hot water storage systems under comparable conditions. This makes the new system much more compact and efficient. Finally, an automatic control strategy is given to achieve the highest COP when solar energy fluctuates.

  18. Solar energy engineering

    Energy Technology Data Exchange (ETDEWEB)

    Sayigh, A.A.M. (ed.)

    1977-01-01

    The scope and advantages of solar energy are dealt with. The nature of the sun, the solar radiation spectrum, the estimation of total, direct, and diffuse radiation, and the heat transfer fundamentals for solar energy application are explained. The fundamentals, fabrication, and uses of various water and air heaters are outlined. Optics and concentrating collectors are dealt with, as well as solar furnaces. The various applications of solar energy are discussed, namely, solar pond, solar distillation, photovoltaic conversion of solar energy, solar refrigeration, solar hydrogen production, space applications, and solar measuring equipment. The cost of solar appliances is discussed. (MHR)

  19. Behavior of a thermoelectric power generation device based on solar irradiation and the earth’s surface-air temperature difference

    International Nuclear Information System (INIS)

    Highlights: • A technical solution to the power supply of wireless sensor networks is presented. • The low voltage produced by TEG is boosted from less than 1 V to more than 4 V. • An output current and voltage of TEG device is acquired as 21.47 mA and 221 mV. • The device successfully provides output power 4.7 mW in no electricity conditions. • The thermo-economic value of TEG device is demonstrated. - Abstract: Motivated by the limited power supply of wireless sensors used to monitor the natural environment, for example, in forests, this study presents a technical solution by recycling solar irradiation heat using thermoelectric generators. Based on solar irradiation and the earth’s surface-air temperature difference, a new type of thermoelectric power generation device has been devised, the distinguishing features of which include the application of an all-glass heat-tube-type vacuum solar heat collection pipe to absorb and transfer solar energy without a water medium and the use of a thin heat dissipation tube to cool the earth surface air temperature. The effects of key parameters such as solar illumination, air temperature, load resistance, the proportional coefficient, output power and power generation efficiency for thermoelectric energy conversion are analyzed. The results of realistic outdoor experiments show that under a state of regular illumination at 3.75 × 104 lx, using one TEG module, the thermoelectric device is able to boost the voltage obtained from the natural solar irradiation from 221 mV to 4.41 V, with an output power of 4.7 mW. This means that the electrical energy generated can provide the power supply for low power consumption components, such as low power wireless sensors, ZigBee modules and other low power loads

  20. Actuaciones de un colector solar de aire para secado de productos agrícolas en países en vías de desarrollo

    OpenAIRE

    Esteban Biescas, Sandra

    2015-01-01

    El uso de secaderos solares para el secado de productos agrícolas es una de las tecnologías apropiadas en crecimiento en los países en vías de desarrollo. En el marco de las tecnologías apropiadas se define el presente Trabajo Fin de Grado para caracterizar el proceso de calentamiento de aire y la capacidad de secado de un secadero solar activo (de convección forzada) de tipo distribuido protegiendo así al máximo los productos agrícolas de los agentes externos. Este sistema se basa en el a...

  1. Energy problems of the central systems of air conditioning; Problemas energeticos de los sistemas centrales de climatizacion

    Energy Technology Data Exchange (ETDEWEB)

    Cardero Corria, Gaspar [Cubanacan, S.A., Varadero (Cuba)

    2003-07-01

    The central systems of air conditioning are widely used in air conditioning production for several reasons among which excel: 1) Better aesthetic of the building, 2) Less noise in the air conditioning premises and 3) Greater yield of the consumed energy. This is indeed the third reason in which this paper will try to contribute with elements that will allow reveal the problem and to identify some possible causes that originate it. The centralized systems of air conditioning must produce conditioned air with lesser power cost than the individual systems, it is that saving which allows to recover an investment that normally surpasses them in 3 to 5 times. Nevertheless, the real numbers do not demonstrate that. [Spanish] Los sistemas centrales de climatizacion son ampliamente usados en la produccion de aire acondicionado por varias razones entre las que sobresalen: 1) Mejor estetica del edificio, 2) Menor ruido en los locales climatizados y 3) Mayor rendimiento de la energia consumida. Es precisamente la tercera razon en la cual este trabajo intentara aportar elementos que permitan develar el problema e identificar algunas posibles causas que lo originan. Los sistemas centralizados de climatizacion deben producir aire acondicionado con un menor gasto energetico que los sistemas individuales, es precisamente ese ahorro lo que permite recuperar una inversion que normalmente los supera en 3 a 5 veces. Sin embargo, los numeros reales no demuestran eso.

  2. A study of the shadowing of galactic cosmic rays by the sun in a quiet phase of solar activity with the Tibet air shower array

    CERN Document Server

    Amenomori, M

    2000-01-01

    We have shown that the Sun's shadow by high energy cosmic rays moves year by year and its behavior is correlated with a time variation of the large-scale structure of the solar and interplanetary magnetic fields. The solar activity was near minimum in the period from 1996 through 1997. Using the data obtained with the Tibet air shower array, we examined the shadowing of cosmic rays by the Sun in this quiet phase of solar cycle, and found that the Sun's shadow was just in the apparent direction of the Sun, though it was observed at the position considerably away from the Sun to the south-west in the period between 1990 and 1993. It is known that the magnetic pole of equivalent solar dipole was reversed during the previous active phase, and near solar minimum the dipole was aligned with the rotating axis, preserving its N-pole on the north pole side of the Sun. This causes the solar magnetic field to shift the Sun's shadow to the east. Thus, the observed results suggest that the shift of the Sun's shadow due to...

  3. Engineering Schottky contacts in open-air fabricated heterojunction solar cells to enable high performance and ohmic charge transport.

    Science.gov (United States)

    Hoye, Robert L Z; Heffernan, Shane; Ievskaya, Yulia; Sadhanala, Aditya; Flewitt, Andrew; Friend, Richard H; MacManus-Driscoll, Judith L; Musselman, Kevin P

    2014-12-24

    The efficiencies of open-air processed Cu2O/Zn(1-x)Mg(x)O heterojunction solar cells are doubled by reducing the effect of the Schottky barrier between Zn(1-x)Mg(x)O and the indium tin oxide (ITO) top contact. By depositing Zn(1-x)Mg(x)O with a long band-tail, charge flows through the Zn(1-x)Mg(x)O/ITO Schottky barrier without rectification by hopping between the sub-bandgap states. High current densities are obtained by controlling the Zn(1-x)Mg(x)O thickness to ensure that the Schottky barrier is spatially removed from the p-n junction, allowing the full built-in potential to form, in addition to taking advantage of the increased electrical conductivity of the Zn(1-x)Mg(x)O films with increasing thickness. This work therefore shows that the Zn(1-x)Mg(x)O window layer sub-bandgap state density and thickness are critical parameters that can be engineered to minimize the effect of Schottky barriers on device performance. More generally, these findings show how to improve the performance of other photovoltaic system reliant on transparent top contacts, e.g., CZTS and CIGS. PMID:25418326

  4. Thermal energy storages analysis for high temperature in air solar systems

    International Nuclear Information System (INIS)

    In this paper a high temperature thermal storage in a honeycomb solid matrix is numerically investigated and a parametric analysis is accomplished. In the formulation of the model it is assumed that the system geometry is cylindrical, the fluid and the solid thermo physical properties are temperature independent and radiative heat transfer is taken into account whereas the effect of gravity is neglected. Air is employed as working fluid and the solid material is cordierite. The evaluation of the fluid dynamic and thermal behaviors is accomplished assuming the honeycomb as a porous medium. The Brinkman–Forchheimer–extended Darcy model is used in the governing equations and the local thermal non equilibrium is assumed. The commercial CFD Fluent code is used to solve the governing equations in transient regime. Numerical simulations are carried out with storage medium for different mass flow rates of the working fluid and different porosity values. Results in terms of temperature profiles, temperatures fields and stored thermal energy as function of time are presented. The effects of storage medium, different porosity values and mass flow rate on stored thermal energy and storage time are shown. - Highlights: • HTTES in a honeycomb solid matrix is numerically investigated. • The numerical analysis is carried out assuming the honeycomb as a porous medium. • The Brinkman–Forchheimer–extended Darcy model is used in the governing equations. • Results are carried out for different mass flow rates and porosity values. • The main effect is due to the porosity which set the thermal energy storage value

  5. Solar radiation exposure of shielded air temperature sensors and measurement error evaluation in an urban environment: a preliminary study in Florence, Italy

    Directory of Open Access Journals (Sweden)

    M. Petralli

    2009-04-01

    Full Text Available Particularly in summer, thermal conditions in urban areas are influenced by solar radiation and human health can be strongly affected by the higher temperature regime increased by the Urban Heat Island effect (UHI. Many studies have been carried out to estimate the temperature distribution in urban areas and some of these use or are based on data collected by meteorological instruments placed within the cities. At microscale, temperature collected by sensors can be influenced by the underlying surface characteristics and the closeness to warm surfaces. The aim of this study is to investigate how different exposure to solar radiation can affect air temperature measurement in streets and gardens. The study was carried out on two different areas in Florence during summer 2007. Shielded air temperature sensors were placed in a street of a high density built-up area and in a green area. Each area was monitored by two sensors, sited in different solar radiation exposure: one in a sunny area and the other in a shaded one. A preliminary data analysis showed a difference in every site between the air temperature values collected by the two sensors especially from the morning to the afternoon. The relationship between air temperature differences and synoptic meteorological conditions were also analyzed. In conclusion, the solar radiation exposure of a monitoring station is an important parameter that must be considered both during the instruments siting and the analysis of data collected by sensors previously placed. The result of this study shows that during particular synoptic conditions, data collected by the two sensors of the same area can be different.

  6. A mathematical model for predicting the performance of the solar energy assisted hybrid air conditioning system, with one-rotor six-stage rotary desiccant cooling system

    International Nuclear Information System (INIS)

    Highlights: • The desiccant wheels used honeycombed silica gel six-stage rotary desiccant cooling system was studied. • The mathematical model has been validated with the experimental data. • The optimal rotation speed increases with increasing the inlet temperature of the regeneration air. - Abstract: A mathematical model for predicting the performance of solar energy assisted hybrid air conditioning system (SEAHACS) is presented. The honeycombed silica gel desiccant wheel is used in this study. One-rotor six-stage rotary desiccant cooling system, (two-stage dehumidification process, two-stage pre-cooling process and two-stage regeneration process) are realized by only one wheel. Three air streams are involved in the present system. The mathematical model has been validated with the experimental data. The range of regeneration air inlet temperature changed from 65 to 140 °C, area ratio of process air to regeneration air change from 1 to 3.57, regeneration air inlet velocity from 1.5 to 5.5 m/s have been examined for a range of rotation speed from 6 to 20 rev/h. The optimization of these parameters is conducted based on the moisture removal capacity D, relative moisture removal capacity, dehumidification coefficient of performance and thermal coefficient of performance. At last, the influences of these main parameters on optimal rotation speed are discussed

  7. Analysis and Design of a Dish/Stirling System for Solar Electric Generation with a 2.7 kW Air-Cooled Engine

    Directory of Open Access Journals (Sweden)

    Beltrán-Chacón R.

    2012-01-01

    Full Text Available This paper presents a mathematical modeling, simulation and design of a solar power system of a parabolic dish with an air-cooled Stirling engine of 2.7 kW. The model used for the solar concentrator, the cavity and the Stirling engine were successfully validated against experimental data. Based on a parametric study, the design of the components of the engine is carried out. The study shows that as system capacity increases, the overall efficiency is limited by the power required by the fan, since the design of the cooler needs greater amounts of heat removal by increasing the air flow without affecting the internal conditions of the process (mass flow of working gas and internal dimensions of the same. The system was optimized and achieves an overall efficiency of solar to electric energy conversion of 26.7%. This study shows that the use of an air-cooled Stirling engine is potentially attractive for power generation at low capacities.

  8. 太阳能制冷空调系统设计与应用初探%Preliminary Study on Design and Application of Solar Air Conditioning System

    Institute of Scientific and Technical Information of China (English)

    周治宏

    2012-01-01

    太阳作为一种可再生的清洁能源,通过一定的能量转换可扩展应用到空调系统上来。本文介绍了太阳能制冷系统的发展现状以及分类,并重点阐述了太阳能吸收式制冷空调系统的设计思路与运行原理。通过这一系统在重庆市节能示范中心的概念示范性设计使用,进一步探讨和展望了太阳能吸收式制冷空调系统未来的推广和发展。%The sun,as a renewable clean energy,can be applied to the air conditioning system by a certain energy conversion.This article describes the development status and classification of solar cooling system,and focuses on design concept and operating principles of solar absorption cooling air conditioning system.With this system used in the concept design of Chongqing Energy-saving Demonstration Center as a demonstration used technology,we can further discuss and prospect the prospective promotion and development of the solar absorption cooling air conditioning system.

  9. Solutions Network Formulation Report. NASA's Potential Contributions for Using Solar Ultraviolet Radiation in Conjunction with Photocatalysis for Urban Air Pollution Mitigation and Increasing Air Quality

    Science.gov (United States)

    Underwood, Lauren; Ryan, Robert E.

    2007-01-01

    This Candidate Solution is based on using NASA Earth science research on atmospheric ozone and aerosols data as a means to predict and evaluate the effectiveness of photocatalytically created surfaces (building materials like glass, tile and cement) for air pollution mitigation purposes. When these surfaces are exposed to near UV light, organic molecules, like air pollutants and smog precursors, will degrade into environmentally friendly compounds. U.S. EPA (Environmental Protection Agency) is responsible for forecasting daily air quality by using the Air Quality Index (AQI) that is provided by AIRNow. EPA is partnered with AIRNow and is responsible for calculating the AQI for five major air pollutants that are regulated by the Clean Air Act. In this Solution, UV irradiance data acquired from the satellite mission Aura and the OMI Surface UV algorithm will be used to help understand both the efficacy and efficiency of the photocatalytic decomposition process these surfaces facilitate, and their ability to reduce air pollutants. Prediction models that estimate photocatalytic function do not exist. NASA UV irradiance data will enable this capability, so that air quality agencies that are run by state and local officials can develop and implement programs that utilize photocatalysis for urban air pollution control and, enable them to make effective decisions about air pollution protection programs.

  10. 中高温太阳能空气集热器及其试验研究%MEDIUM-HIGH TEMPERATURE SOLAR AIR COLLECTOR AND EXPERIMENT RESEARCH

    Institute of Scientific and Technical Information of China (English)

    肖红升; 白建波; 王登锋; 夏宁

    2012-01-01

    Becanse most of solar air collectors can only provide low temperature air at present, a new type of solar air collector with medium-high temperature air was put forward. It is composed of three parts; a compound parabolic concentrating (CPC) collector is used to focus sunlight; an evacuated solar collector tube is used to collect heat; a U-type tube, which adopts heat from the envelope, is used to increase air temperature. Between the tube and the envelope, the composition of graphite and glycerin is adopted as the heat transfer medium. With multiple serial of the apparatuses, the temperature of the heated air can reach over 2001. The heat transfer performances of key parts of solar air collector were analyzed. Furthermore, the elementary experiment performance was described.%针对目前太阳能空气集热器普遍温度不高的情况,设计了一种新型的中高温太阳能空气集热器,采用复合抛物面聚光集热器(CPC)作为聚热部件,采用真空集热管作为集热部件,空气加热部分则由真空集热管和U型管之间热传递配合完成,真空集热管和U型管之间采用新型导热材料——石墨与甘油混合物作为传热介质,该集热器的多级串联可获得200℃以上的高温空气;为了评估该集热器的性能,对该集热器关键部分的传热特性进行分析,并对多级情况下的集热器的中高温性能进行初步实验研究.

  11. Analisa Kinerja Termal Solar Apparatus Panel pada Alat Destilasi Air Payau dengan Sistem Evaporasi Uap Tenaga Matahari Menggunakan CFD

    OpenAIRE

    Nadia Handayani; Taufik Fajar Nugroho; Sutopo Purwono Fitri

    2014-01-01

    Upaya penyaluran air bersih ke daerah pesisir belum dilakukan secara merata sehingga masyarakat masih mengkonsumsi air payau untuk kehidupan sehari-hari. Meskipun telah banyak dikembangkan alat destilasi air laut menjadi air tawar, namun masih memiliki sistem yang kompleks dan biaya yang mahal, sehingga dikembangkan alat destilasi air menggunakan sistem evaporasi uap dengan sumber tenaga matahari. Untuk mengetahui kinerja termal alat destilasi ini, maka dilakukan penelitian dengan metode simu...

  12. 太阳能技术在汽车空调上的应用%The application of solar - energy technology in the automotive air conditioning

    Institute of Scientific and Technical Information of China (English)

    施军锞; 祁影霞

    2012-01-01

    针对国家对环境污染及能源有效利用的重视,提出了现有汽车空调存在的问题,通过分析日渐成熟的高效太阳能电池技术、充放电控制技术,特别是具有高光电转化效率材料的不断涌现,以及嵌入式单片机技术的不断创新,为实现汽车空调热电制冷以及太阳能天窗的商业化应用提供了必要的技术支持,从而解决现有的蒸汽压缩制冷所面临的制冷剂替换及耗油问题,实现环境的保护和能源的有效利用.%Due to the environment pollution from the refrigerants of traditional air conditioners, a new typf of solar - energy air conditioner in automobiles was put forward. This paper analysed the high efficience of solar - energy cells, charging and discharging techniques and high photoelectrical conversion materials. With embedded micro - controller technology development, the thermoelectrical cooling technology could he used in air conditioners in automobiles.

  13. Influence of air exposure duration and a-Si capping layer thickness on the performance of p-BaSi2/n-Si heterojunction solar cells

    Science.gov (United States)

    Takabe, Ryota; Yachi, Suguru; Du, Weijie; Tsukahara, Daichi; Takeuchi, Hiroki; Toko, Kaoru; Suemasu, Takashi

    2016-08-01

    Fabrication of p-BaSi2(20nm)/n-Si heterojunction solar cells was performed with different a-Si capping layer thicknesses (da-Si) and varying air exposure durations (tair) prior to the formation of a 70-nm-thick indium-tin-oxide electrode. The conversion efficiencies (η) reached approximately 4.7% regardless of tair (varying from 12-150 h) for solar cells with da-Si = 5 nm. In contrast, η increased from 5.3 to 6.6% with increasing tair for those with da-Si = 2 nm, in contrast to our prediction. For this sample, the reverse saturation current density (J0) and diode ideality factor decreased with tair, resulting in the enhancement of η. The effects of the variation of da-Si (0.7, 2, 3, and 5 nm) upon the solar cell performance were examined while keeping tair = 150 h. The η reached a maximum of 9.0% when da-Si was 3 nm, wherein the open-circuit voltage and fill factor also reached a maximum. The series resistance, shunt resistance, and J0 exhibited a tendency to decrease as da-Si increased. These results demonstrate that a moderate oxidation of BaSi2 is a very effective means to enhance the η of BaSi2 solar cells.

  14. Watergy. A moist air solar collector system with an integrated brine circuit for te heating of buildings; Watergy. Ein Feuchtluft-Solarkollektorsystem mit integriertem Solekreislauf zur Gebaeudeheizung

    Energy Technology Data Exchange (ETDEWEB)

    Buchholz, Martin; Buchholz, Reiner; Geyer, Philipp; Schmidt, Marco [Technische Univ. Berlin (Germany). Fachgebiet Gebaeudetechnik und Entwerfen

    2010-07-01

    Due to the Renewable Energy Law 2009, the proportion of renewable energies in the overall energy consumption of the European Union increased to 20 %. Currently, the proportion of the total heat energy consumption in Germany amounts nearly 40 %. Previous concepts for the storage of heat in the summer for use in winter are not convincing. The improvement of the efficiency of solar collectors and an increase in the collector surface result in increased investment costs and costs for heat supply. Thus, solar collector systems should be optimized for the operation of heaters. This is done for example by reducing the mean collector temperature using a combination of solar collectors with a heat pump. However, heat pumps are operated by means of electrical energy. Electrical energy can not be saved in the summer in order to be used in the winter. Under this aspect, the authors of the contribution under consideration report on the Watergy concept - a moist air solar collector system with an integrated brine circuit for heating of buildings.

  15. 太阳能-空气源热泵热水系统节能分析%SOLAR-AIR SOURCE HEAT PUMP HOT WATER SYSTEM ENERGY EFFICIENCY ANALYSIS

    Institute of Scientific and Technical Information of China (English)

    王冠竹; 刘学来

    2011-01-01

    介绍了太阳能生活热水系统,以山东省为例,对太阳能热水器配备空气源热泵的热水系统进行了节能效益分析.结果表明,配备空气源热泵的太阳能热水系统回收期为4.21年,对我国走低碳经济之路有重要的参考价值.%This article describes the solar hot water system. It conducts the energy-saving benefit a-nalysis of solar energy -air source heat pump hot water system. The results show that the payback period of this system is 4.21 years. It has important reference value for going low-carbon economy road in China.

  16. Craft-joule project: air-cooled water LiBr absorption cooling machine of low capacity for air conditioning (ACABMA)

    Energy Technology Data Exchange (ETDEWEB)

    Oliva, A; Castro, J; Perez Segarra, C.D [Universitat Politecnica de Catalunya, Barcelona (Spain); Lucena, M.A [Instituto Nacional de Tecnica Aeroespecial (Spain)] (and others)

    2000-07-01

    strategy in order to obtain stable work from the machine. [Spanish] El Proyecto ACABMA (Air-Cooled Water-LiBr Absorption Cooling Machine of Low Capacity for Air Conditioning) es un Proyecto Craft-Joule dentro del marco del Programa de Energia No Nuclear Joule III, coordinado por el Centre Tecnologico de Transferecia de Calor (CTTC). El objetivo principal de este proyecto es el desarrollo de una nueva maquina de enfriamiento de absorcion de aire enfriado para aire acondicionado, en el mercado del sector de baja energia. Haciendo uso de la tecnologia de agua-LiBr junto con la caracteristica del enfriamiento de aire, es posible alcanzar una mejor relacion entre calidad (en terminos de rendimiento, ecologia, etc.) y precio de tales maquinas de absorcion, que las existentes en el mercado. El enfriamiento por aire en vez del enfriamiento con agua ahorra costos de instalacion especialmente en sistemas pequenos y modifica la demanda de agua de enfriamiento (un aspecto importante en los paises de Europa meridional), incrementando asi el rango de aplicacion posible. El principal interes para los proponentes del SME es aprovechar la ventaja de la creciente demanda de enfriadores en Europa, especialmente en los paises del sur. Otro punto de interes para los proponentes SME es el desarrollo de un sistema de calefaccion/enfriamiento mas barato en terminos de costos de energia e instalacion. En este momento los costos de sistemas de enfriamiento solar son aproximadamente 30% mas caros que los convencionales. Una maquina de absorcion mas barata debido a la caracteristica de enfriamiento de aire junto con la posibilidad de ahorro de energia por bajas temperaturas del generador, que permitan la maquina de absorcion para aplicaciones solares o calor de desperdicio, llevara a los sistemas de calefaccion y enfriamiento solares a ser mas competitivos que los convencionales. Para alcanzar esa meta, los siguientes pasos son necesarios, y se llevaran a cabo en este proyecto: i) la solucion del

  17. Weather Effect on the Solar Adsorption Air-conditioning System using Activated Carbon Fiber/Ethanol as Pair of Refrigeration: A Case Study of Malaysia

    Directory of Open Access Journals (Sweden)

    Alkhair M. Abdul Majeed

    2014-02-01

    Full Text Available This study indicates the simulation analysis of the solar adsorption cycle using the activated carbon fiber/ethanol as the pair of refrigeration in Malaysia. The heat source used was evacuated tube collectors. The cycle is used for the purpose of air-conditioning for two temperature levels, where the cooling load can be 7°C. TRNSYS simulation software was used to model the system with the weather data of Malaysia. The results showed that the weather has a high effect on the performance of the cycle. Both the cooling capacity and the COP were calculated in this study.

  18. Weather Effect on the Solar Adsorption Air-conditioning System using Activated Carbon Fiber/Ethanol as Pair of Refrigeration: A Case Study of Malaysia

    OpenAIRE

    Alkhair M. Abdul Majeed; M.Y. Suliman; Sopian, K.

    2014-01-01

    This study indicates the simulation analysis of the solar adsorption cycle using the activated carbon fiber/ethanol as the pair of refrigeration in Malaysia. The heat source used was evacuated tube collectors. The cycle is used for the purpose of air-conditioning for two temperature levels, where the cooling load can be 7°C. TRNSYS simulation software was used to model the system with the weather data of Malaysia. The results showed that the weather has a high effect on the performance of the...

  19. Efficient, air-stable colloidal quantum dot solar cells encapsulated using atomic layer deposition of a nanolaminate barrier

    KAUST Repository

    Ip, Alexander H.

    2013-12-23

    Atomic layer deposition was used to encapsulate colloidal quantum dot solar cells. A nanolaminate layer consisting of alternating alumina and zirconia films provided a robust gas permeation barrier which prevented device performance degradation over a period of multiple weeks. Unencapsulated cells stored in ambient and nitrogen environments demonstrated significant performance losses over the same period. The encapsulated cell also exhibited stable performance under constant simulated solar illumination without filtration of harsh ultraviolet photons. This monolithically integrated thin film encapsulation method is promising for roll-to-roll processed high efficiency nanocrystal solar cells. © 2013 AIP Publishing LLC.

  20. 整体式太阳能空气集热器热性能研究%Thermal Performance Research of the Integral Solar Air Collector

    Institute of Scientific and Technical Information of China (English)

    吴国玉; 胡明辅; 毕二朋; 袁江

    2012-01-01

    A new type of integral solar air heat collector is introduced in the paper. According to a simplified model, a CFD software is applied to simulate the fields of flow, pressure and temperature. It is shown that in comparison with the integral solar air heat collector, there is a stagnation zone of flow in the inner part of the traditional assembly arrayed collector, the inner temperature distribution is not uniform, and there are also local high temperature zones on heat absorbing plates. The distributions of inner flow field, pressure field and temperature field are more uniform in the proposed one, the temperature gradient is obvious, and the effect of convective heat exchange between heat absorbing plates and air is better. So the heat property of the integral solar air heat collector is better than that of the traditional assembly arrayed air collector.%对一种新型的整体式太阳能空气集热器,根据简化的物理模型利用CFD软件对集热器内部的流场、压力场和温度场进行数值模拟分析,并与传统拼装式集热器阵列进行对比.结果表明,传统拼装式集热器阵列内部存在流动的滞留区,内部温度分布不均匀,吸热板有局部的高温区域;整体式空气集热器内部流场、压力场和温度场分布比较均匀,有明显的温度梯度,吸热板与空气能够更好的进行对流换热.因此,整体式空气集热器的热性能优于传统拼装式空气集热器阵列.

  1. Estabilidade sensorial de suco de maracujá pronto para beber acondicionado em latas de aço Sensorial stability of ready-to-drink passion fruit juice packaged in tinplate cans

    Directory of Open Access Journals (Sweden)

    Elisabete Segantini Saron

    2007-12-01

    Full Text Available O estudo teve por objetivo avaliar a preservação das características sensoriais e físico-químicas de suco de maracujá pronto para beber acondicionado em latas de três peças em folha-de-flandres eletrossoldadas, com diferentes condições de envernizamento interno do corpo e costura lateral, através de teste de estocagem. O suco de maracujá foi acondicionado em latas com camada nominal interna de 2,0 g de Sn.m-2, com três sistemas de revestimento orgânico interno e condicionado a 25 e 35 °C durante 360 dias. Ocorreu um acentuado decréscimo do conteúdo de ácido ascórbico até os 180 dias, mantendo-se estável até 360 dias em todas as condições estudadas. A avaliação de cor demonstrou o escurecimento do suco até os 120 dias e posteriormente sua descoloração, entre os 300 e 360 dias, nas duas temperaturas estudadas. A avaliação sensorial durante a estocagem demonstrou desempenho similar para todas as latas, sendo inferior apenas para a lata Pó a 35 °C. As principais alterações verificadas no produto ao longo da estocagem foram associadas às alterações intrínsecas à bebida e não à interação suco/embalagem. O estudo permitiu concluir que os três sistemas de envernizamento das latas estudadas podem ser utilizados no acondicionamento de suco de maracujá pronto para beber para uma vida-de-prateleira mínima de 12 meses.The purpose of this work was to evaluate the preservation of the sensorial and physicochemical characteristics of ready-to-drink passion fruit juice packaged in three-piece welded tinplate cans with different internal coatings of the body and side strips, based on a storage test. The product evaluated was ready-to-drink passion fruit juice packaged in cans with an internal layer of 2.0 g.m-2 of tin, with three inner organic coating systems, stored at 25 and 35 °C for 360 days. A sharp decrease in ascorbic acid content was recorded up to day 180, after which it remained constant until the end of

  2. 全玻璃真空管太阳能空气集热器热性能试验方法研究%STUDY ON MEASUREMENT OF THERMAL PERFORMANCE OF ALL-GLASS EVACUATED TUBULAR SOLAR AIR HEATER

    Institute of Scientific and Technical Information of China (English)

    王志峰

    2001-01-01

    全玻璃真空管空气集热器是一种热损较小的太阳能空气加热装置。该文对该类集热器热性能评价方法进行了研究,并对集热器的时间常数、热延迟常数、角系数修正因子及瞬时热效率的实验方法进行了初步的实验研究。研究表明,用热延迟常数比时间常数能更好地反映真空管集热器的热性能,真空管集热器的角系数修正因子在垂直入射时最小。%Evacuated tubular solar collector is good for solar air heater as its low heat loss.A study on the thermal performance of the solar air heater is presented.The methods to test the time constant,resident time,incident angular modifier and instantaneous thermal efficiency are suggested.The resident time would be better than time constant to represent the thermal properties of the solar air heater.The incident angular modifier will be minimal at solar noon for the evacuated tubular solar air heater.

  3. Reducing a solar-assisted air-conditioning system’s energy consumption by applying real-time occupancy sensors and chilled water storage tanks throughout the summer: A case study

    International Nuclear Information System (INIS)

    Highlights: • We present an innovative occupancy and chilled water storage-based operation mode. • This mode was implemented to the solar-assisted air-conditioning system. • It permits to save 42% of total electrical energy during one cooling period. • It allows storing the excess cooling capacity of the absorption chiller. • It prevents the sudden start/stop (on/off cycles) of the absorption chiller. - Abstract: This study describes an innovative occupancy and chilled-water storage-based operation sequence implemented in a solar-assisted air-conditioning system. The core purpose of this solar-assisted air-conditioning system is to handle the cooling and heating load of the Solar Energy Research Centre (CIESOL), thus minimising its environmental impact. In this study, the cooling mode was investigated with special attention focused on the chilled-water storage circuit. The critical concern is that the solar-assisted air-conditioning system should always operate considering the actual load conditions, not using an abstract maximum load that is predetermined during the system’s design process, which can lead to energy waste during periods of low occupancy. Thus, the fundamental problem is to identify the optimum operation sequence for the solar-assisted air-conditioning system that provides the best energy performance. The significance of this work lies in the demonstration of a new operation strategy that utilises real-time occupancy monitoring and chilled-water storage tanks to improve the efficiency of solar-assisted air-conditioning systems, thereby reducing their electricity consumption. Adopting this strategy resulted in a large energy-saving potential. The results demonstrate that during one cooling period, it is possible to conserve approximately 42% of the total electrical energy consumed by the system prior to the adoption of this operation strategy

  4. Solar-Powered, Liquid-Desiccant Air Conditioner for Low-Electricity Humidity Control: Report and Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Dean, J.; Kozubal, E.; Herrmann, L.; Miller, J.; Lowenstein, A.; Barker, G.; Slayzak, S.

    2012-11-01

    The primary objective of this project was to demonstrate the capabilities of a new high-performance, liquid-desiccant dedicated outdoor air system (DOAS) to enhance cooling efficiency and comfort in humid climates while substantially reducing electric peak demand at Tyndall Air Force Base (AFB), which is 12 miles east of Panama City, Florida.

  5. Performance assessment of a solar-powered air quality and weather station placed on a school rooftop in Hong Kong

    Science.gov (United States)

    Emerging air pollution measurement technologies that require minimal infrastructure to deploy may lead to new insights on air pollution spatial variability in urban areas. Through a collaboration between the USEPA and HKEPD, this study evaluates the performance of a compact, roo...

  6. Conocimientos y prácticas frente a la exposición solar y tamizaje de cáncer de piel. Medellín, mayo - junio de 2000

    Directory of Open Access Journals (Sweden)

    Marta Gaviria

    2001-04-01

    Full Text Available

    El melanoma maligno cutáneo ha mostrado en las últimas décadas un aumento en su incidencia; para 1992 ésta fue de 1:105, ientras que para el año 2000 se esperaba una incidencia de 1:75. Aunque estudios epidemiológicos internacionales evidencian que la exposición a la radiación solar constituye la principal causa de melanoma en poblaciones de piel blanca, la distribución de éste por sitio corporal o está estrechamente relacionada con las áreas de máxima exposición sino que compromete áreas intermitentemente expuestas. Para que se desarrolle el cáncer de piel se requiere una combinación de factores constitucionales y ambientales. Entre las características
    fenotípicas se encuentran: el color claro de la piel, la incapacidad para broncearse, cabello de color rojo o amarillo y la presencia de efélides en la infancia. En cuanto a los factores ambientales, la depleción de la capa de ozono por los clorofluorocarbonos liberados hacia la atmósfera por los envases de aerosol, los aires acondicionados y los
    refrigeradores, puede aumentar la cantidad de radiación ultravioleta ue alcanza la superficie terrestre incrementando la incidencia de estos tumores. en personas con trabajos al aire libre y alta exposición recreativa al sol; en dichas personas se encuentra una mayor incidencia de cáncer de piel, disminuyendo progresivamente la edad de aparición de esta enfermedad.

     

     

  7. 吸收式太阳能制冷空调系统的性能分析%Performance analysis of a solar absorption air-conditioning system

    Institute of Scientific and Technical Information of China (English)

    谭军毅; 姚莉; 卢挺浩; 余国保

    2012-01-01

    An absorption solar refrigeration air-conditioning system, which consists of solar heat collector, absorption refrigerant unit, auxiliary heating device and intelligent controller is introduced in this paper. The operation data which has been collected for more than one year is organized, also a performance analysis in allusion to typical summer/winter work condition is presented, and an economical efficiency calculation comparing with conventional air-condition has been carried out to get the payback period of this system.%介绍了一个吸收式太阳能制冷空调系统,该系统由太阳能集热器、吸收式制冷机组、辅助加热装量、智能控制器等部分组成.文章对该系统一年多的运行数据进行了采集和整理,针对夏季与冬季的典型工况进行了性能分析,并与常规空调进行了经济性对比,分析其投资回收期.

  8. Heat Transfer Enhancement in a Solar Air Heater with Roughened Duct Having Arc-Shaped Elements as Roughness Element on the Absorber Plate

    Science.gov (United States)

    Singh, Anil Prakash; Goel, Varun; Vashishtha, Siddhartha; Kumar, Amit

    2016-07-01

    An experimental study has been carried out for the heat transfer and friction characteristics for arc shaped roughness element used in solar air heaters. Duct has an aspect ratio (W/H) of 11, relative roughness pitch (p/e) range of 4-16, relative roughness height (e/D) range of 0.027-0.045, Reynolds number ( Re) range of 2200-22,000 and arc angle (α) was kept constant at 60°. The effects of Re, relative roughness pitch (p/e) and relative roughness height (e/D) on heat transfer and friction factor have been discussed. The results obtained for Nusselt number and friction factor has been compared with smooth solar air heater to see the enhancement in heat transfer and friction factor and it is found out that considerable enhancement takes place in case of heat transfer as well as in friction factor. Correlations were also developed for Nusselt number and friction factor. Thermo-hydraulic performance parameter is also calculated for the same.

  9. Effect of gap position in broken V-rib roughness combined with staggered rib on thermohydraulic performance of solar air heater

    Energy Technology Data Exchange (ETDEWEB)

    Patil, Anil K.; Saini, J.S.; Kumar, K. [D.I.T., Dehradun (India). Dept. of Mechanical Engineering

    2011-07-01

    Application of artificial roughness on underside of absorber surface has been found to be effective technique to improve thermo hydraulic performance of solar air heaters. In progression to the previous researches, the present study discloses the effect of broken V-rib roughness combined with staggered ribs on heat transfer and friction in a flow through artificially roughened solar air heater duct. The experimentations were performed to collect the data on heat transfer and friction by varying the Reynolds number (Re) between 3000 and 17,000, relative gap position (s'/s) from 0.2 to 0.8, for the fixed values of relative staggered rib pitch p'/p = 0.6, relative staggered rib size r/e = 1, relative roughness pitch p/e = 10, relative roughness height e/D{sub h} = 0.043, relative gap size g/e = 1, and angle of attack {alpha} = 60 . The present roughness geometry with relative gap position (s'/s) of 0.6 corresponding to flow Reynolds number (Re) of 13,150 yields the best thermohydraulic performance. (orig.)

  10. Facile and Scalable Fabrication of Highly Efficient Lead Iodide Perovskite Thin-Film Solar Cells in Air Using Gas Pump Method.

    Science.gov (United States)

    Ding, Bin; Gao, Lili; Liang, Lusheng; Chu, Qianqian; Song, Xiaoxuan; Li, Yan; Yang, Guanjun; Fan, Bin; Wang, Mingkui; Li, Chengxin; Li, Changjiu

    2016-08-10

    Control of the perovskite film formation process to produce high-quality organic-inorganic metal halide perovskite thin films with uniform morphology, high surface coverage, and minimum pinholes is of great importance to highly efficient solar cells. Herein, we report on large-area light-absorbing perovskite films fabrication with a new facile and scalable gas pump method. By decreasing the total pressure in the evaporation environment, the gas pump method can significantly enhance the solvent evaporation rate by 8 times faster and thereby produce an extremely dense, uniform, and full-coverage perovskite thin film. The resulting planar perovskite solar cells can achieve an impressive power conversion efficiency up to 19.00% with an average efficiency of 17.38 ± 0.70% for 32 devices with an area of 5 × 2 mm, 13.91% for devices with a large area up to 1.13 cm(2). The perovskite films can be easily fabricated in air conditions with a relative humidity of 45-55%, which definitely has a promising prospect in industrial application of large-area perovskite solar panels.

  11. Facile and Scalable Fabrication of Highly Efficient Lead Iodide Perovskite Thin-Film Solar Cells in Air Using Gas Pump Method.

    Science.gov (United States)

    Ding, Bin; Gao, Lili; Liang, Lusheng; Chu, Qianqian; Song, Xiaoxuan; Li, Yan; Yang, Guanjun; Fan, Bin; Wang, Mingkui; Li, Chengxin; Li, Changjiu

    2016-08-10

    Control of the perovskite film formation process to produce high-quality organic-inorganic metal halide perovskite thin films with uniform morphology, high surface coverage, and minimum pinholes is of great importance to highly efficient solar cells. Herein, we report on large-area light-absorbing perovskite films fabrication with a new facile and scalable gas pump method. By decreasing the total pressure in the evaporation environment, the gas pump method can significantly enhance the solvent evaporation rate by 8 times faster and thereby produce an extremely dense, uniform, and full-coverage perovskite thin film. The resulting planar perovskite solar cells can achieve an impressive power conversion efficiency up to 19.00% with an average efficiency of 17.38 ± 0.70% for 32 devices with an area of 5 × 2 mm, 13.91% for devices with a large area up to 1.13 cm(2). The perovskite films can be easily fabricated in air conditions with a relative humidity of 45-55%, which definitely has a promising prospect in industrial application of large-area perovskite solar panels. PMID:27428311

  12. Analysis of the total solar irradiance composite and their contribution to global mean air surface temperature rise

    Science.gov (United States)

    Scafetta, N.

    2008-12-01

    Herein I discuss and propose updated satellite composites of the total solar irradiance covering the period 1978-2008. The composites are compiled from measurements made with the three ACRIM experiments. Measurements from the NIMBUS7/ERB, the ERBS/ERBE satellite experiments and a total solar irradiance proxy reconstruction are used to fill the gap from June 1989 to October 1991 between ACRIM1 and ACRIM2 experiments. The result of the analysis does suggests that the total solar irradiance did increase from 1980 to 2002. The climate implications of the alternative satellite composites are discussed by using a phenomenological climate model which depends on two characteristics time response at tau1 =0.4 year and tau2=8-12 years, as determined phenomenologically [Scafetta, JGR 2008]. Reconstructions of total solar irradiance signature on climate during the last four centuries are discussed. The solar variability appears to have significantly contributed to climate change during the last four centuries, including the last century. Indirectly, the model suggests that the preindustrial climate experienced a large variability which is incompatible with an Hockey Stick temperature graph.

  13. American Recovery and Reinvestment Act (ARRA) Federal Energy Management Program Technical Assistance Project 224 Altus Air Force Base Solar Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Russo, Bryan J.

    2010-09-30

    The principal goal of this project was to evaluate altus Air Force Base for building integrated silicon or thin film module photovoltaic opportunities. This report documents PNNL's efforts and documents study conclusions.

  14. NASA's Potential Contributions for Using Solar Ultraviolet Radiation in Conjunction with Photocatalysis for Urban Air Pollution Mitigation

    Science.gov (United States)

    Ryan, robert E.; Underwood, Lauren W.

    2007-01-01

    More than 75 percent of the U.S. population lives in urban communities where people are exposed to levels of smog or pollution that exceed the EPA (U.S. Environmental Protection Agency) safety standards. Urban air quality presents a unique problem because of a number of complex variables, including traffic congestion, energy production, and energy consumption activities, all of which can contribute to and affect air pollution and air quality in this environment. In environmental engineering, photocatalysis is an area of research whose potential for environmental clean-up is rapidly developing popularity and success. Photocatalysis, a natural chemical process, is the acceleration of a photoreaction in the presence of a catalyst. Photocatalytic agents are activated when exposed to near UV (ultraviolet) light (320-400 nm) and water. In recent years, surfaces coated with photocatalytic materials have been extensively studied because pollutants on these surfaces will degrade when the surfaces are exposed to near UV light. Building materials, such as tiles, cement, glass, and aluminum sidings, can be coated with a thin film of a photocatalyst. These coated materials can then break down organic molecules, like air pollutants and smog precursors, into environmentally friendly compounds. These surfaces also exhibit a high affinity for water when exposed to UV light. Therefore, not only are the pollutants decomposed, but this superhydrophilic nature makes the surface self-cleaning, which helps to further increase the degradation rate by allowing rain and/or water to wash byproducts away. According to the Clean Air Act, each individual state is responsible for implementing prevention and regulatory programs to control air pollution. To operate an air quality program, states must adopt and/or develop a plan and obtain approval from the EPA. Federal approval provides a means for the EPA to maintain consistency among different state programs and ensures that they comply with the

  15. Study on heat and mass transfer between a greenhouse considered as a solar air heater and a rock packed bed as ambient control system

    International Nuclear Information System (INIS)

    A general study on heat transfer in dry packed beds is made, with special emphasis in comparing different transient models and in identifying the required conditions by which the attained results are equivalent. The differences in thermal behaviour on packed beds, when simultaneous heat mass transfer occurs as wet air is used as heat transfer fluid and exchanges heat and water with the solid in the bed, is analyzed. We modelize wet packed beds considering them as one dimension adsorbents beds, with dispersive and non-dispersive models, where adsorption, condensation-evaporation and liquid water downward flow from condensate phenomena are present. Models were solved numerically and experiments with a rock bed with dry and wet air through it, were made to test assumptions and to further understand the behavior of the system, obtaining a pretty good agreement between expected and measured profiles of the temperature evolution within the packed bed. As a possible application of the wet rock bed for storage purposes, a forced ventilation greenhouse was characterized as a wet air solar heater and analyzed the energetic potential of storing the heat that has to be rejected during daytime to control the crop ambient conditions, in a rock bed for later use at night for heating. (author)

  16. Experimental study of heat transfer enhancement in solar air heater with different angle of attack of V-down continuous ribs

    Science.gov (United States)

    Istanto, Tri; Danardono, Dominicus; Yaningsih, Indri; Wijayanta, Agung Tri

    2016-06-01

    In this paper, an experimental study on the effect of angle attack in V-down continuous ribs on heat transfer and friction factor in an artificially roughened air heater duct is presented. The electric heater with a constant heat flux as a simulation of the indoor testing solar air heater is used to heat the roughened part of rectangular duct while other parts were insulated. The system and operating conditions were used to decide the range of parameters for the study. The ratio of the width to height of the duct (W/H) was 12, the relative roughness pitch (p/e) was 10, the relative roughness height (e/Dh) was 0.033 and the angle of attack of flow (α) was 30-80°. The air flow rate corresponded to Reynolds number between 3500 -10,000. The result of heat transfer and friction factor had been compared to those for smooth duct under similar flow and thermal boundary condition. The thermo-hydraulic performance also had been considered. As a result, the maximum enhancement of Nusselt number (Nu) and friction factor(f) were 2.34 and 2.45 times, respectively. For each variation of angle attack of flow, the thermo-hydraulic performance has been compared and the result shows that a V-down continuous rib with the angle of attack of flow as 60° gave the best thermo-hydraulic performance.

  17. Irreversibility analysis of non isothermal flat plate solar collectors for air heating with a dimensionless model; Analisis de las irreversibilidades en colectores solares de placas planas no isotermicos para calentamiento de aire utilizando un modelo adimensional

    Energy Technology Data Exchange (ETDEWEB)

    Bracamonte-Baran, Johane Hans; Baritto-Loreto, Miguel Leonardo [Universidad Central de Venezuela (Venezuela)]. E-mails: johanehb@gmail.com; johane.bracamonte@ucv.ve; miguel.baritto@ucv.ve

    2013-04-15

    The dimensionless model developed and validated by Baritto and Bracamonte (2012) for the thermal behavior of flat plate solar collector without glass cover is improved by adding the entropy balance equation in a dimensionless form. The model is solved for a wide range of aspect ratios and mass flow numbers. A parametric study is developed and the distribution of internal irreversibilities along the collector is analyzed. The influence of the design parameters on the entropy generation by fluid friction and heat transfer is analyzed and it is found that for certain combinations of these parameters optimal thermodynamic operation can be achieved. [Spanish] En el presente trabajo, el modelo adimensional desarrollado y validado por Baritto y Bracamonte (2012) para describir el comportamiento termico de colectores solares de placas planas sin cubierta transparente, se complementa con la ecuacion adimensional de balance de entropia para un elemento diferencial de colector solar. El modelo se resuelve para un amplio rango de valores de relaciones de aspecto y numero de flujo de masa. A partir de los resultados del modelo se desarrolla un analisis detallado de la influencia de estos parametros sobre la distribucion de irreversibilidades internas a lo largo del colector. Adicionalmente se estudia la influencia de estos parametros sobre los numeros de generacion de entropia por friccion viscosa, por transferencia de calor y total. Se encuentra que existen combinaciones de los parametros antes mencionados, para los cuales, la operacion del colector es termodinamicamente optima para numeros de flujo de masa elevados.

  18. Air/liquid collectors

    DEFF Research Database (Denmark)

    Jensen, Søren Østergaard; Olesen, Ole; Kristiansen, Finn Harken

    1997-01-01

    This report determine efficiency equations for combined air/liquid solar collectors by measurements on to different air/liquid collectors. Equations which contain all relevant informations on the solar collectors. A simulation program (Kviksol) has been modified in order to be able to handle...... this kind of collectors. The modified simulation program has been used for the determination of the surplus in performance which solar heating systems with this type of solar collectors for combined preheating of ventilation air and domestic hot water will have. The simulation program and the efficiency...

  19. Enhancement of fill factor in air-processed inverted organic solar cells using self-assembled monolayer of fullerene catechol

    Science.gov (United States)

    Jeon, Il; Ogumi, Keisuke; Nakagawa, Takafumi; Matsuo, Yutaka

    2016-08-01

    [60]Fullerene catechol self-assembled monolayers were prepared and applied to inverted organic solar cells by an immersion method, and their energy conversion properties were measured. By introducing fullerenes at the surface, we improved the hole-blocking capability of electron-transporting metal oxide, as shown by the fill factor enhancement. The fullerene catechol-treated TiO x -containing device gave a power conversion efficiency (PCE) of 2.81% with a fill factor of 0.56 while the non treated device gave a PCE of 2.46% with a fill factor of 0.49. The solar cell efficiency improved by 13% compared with the non treated reference device.

  20. A New Type of Complex System of Solar Energy Air Source Heat Pump Water Heater%一种新型的太阳能——空气源复合热泵热水器系统

    Institute of Scientific and Technical Information of China (English)

    王军军

    2011-01-01

    基于太阳能热利用技术、空气源热泵热水器理论,介绍了一种将太阳能与空气源相结合的双热源热泵热水器系统。该系统可充分利用太阳能加热生活用热水,辅以空气源热泵来满足太阳辐射照度不足时的用热水需求,同时用太阳能辅助加热来解决低温环境下空气源热泵运行工况恶劣的问题。系统充分利用了低品位的太阳能,保证稳定性,又可提高夏季阴雨天气、过渡季节及冬季太阳能热水器的热水温度,对于节约能源和环境保护具有重要意义。%Based on the technology of solar thermal and the theory of air-source heat pump water heater, a combined water heater system about solar and air source heat pump was introduced. The system Could make full use of solar energy to heat domestic hot water, combined with air-source heat pump to meet the shortage of solar irradiance when the hot water demand, and the auxiliary heating with solar energy to solve the problems of air source heat pump operating conditions in low temperature. The system took full use of the low-grade solar energy, and stability could be assured. And it could improve the temperature of the water in solar water heaters in rainy summers, transition seasons and winters. The system had significance for energy conservation and environmental protection.

  1. Solar Desalination System by Humidification Dehumidification Method

    OpenAIRE

    Sousi, Abdulla

    2013-01-01

    ABSTRACT: A humidification/dehumidification (HDH) solar desalination unit having combined solar water/air heater was designed constructed and experimentally investigated. The main components of the desalination system are the combined solar air/water heater collector with double glazing, humidifier (evaporator), dehumidifier (condenser), circulating pump, fan and a storage tank. Both air and saline (or brackish water) were heated in a single combined solar water/air heater. The effect of air ...

  2. 太阳能-空气复合热源热泵热水系统%Solar-air composite heat source heat pump hot water system

    Institute of Scientific and Technical Information of China (English)

    王岗; 全贞花; 赵耀华; 侯隆澍; 徐俊芳; 邓月超

    2014-01-01

    In the light of low efficiency of photovoltaic power generation and the problems of air source heat pump applied in cold regions, a composite heat exchanger evaporator is developed and a new type of solar-air composite heat source heat pump hot water system is designed in this study, which is comprised of independent solar photovoltaic-thermal collector based on flat plate micro heat pipe and air source heat pump. The performance of heat pump hot water system is evaluated experimentally under different operating conditions, including water temperature of the tank, heating time of hot water, suction and discharge pressure, consumption of compressor power and heat pump coefficient of performance (COP), etc. Experimental results show that at ambient temperature of 5℃, 10℃ and 15℃, with 73 L hot water heated by heat pump and water temperature in the tank ranged from 15℃ to 50℃, the running time of composite heat source operation is shorter than that of separate air heat source operation, decreased by 5.14%, 10.29% and 11.38%, respectively. COPs are increased by 5.99%, 9.28%and 11.96%, respectively.%针对光伏发电效率较低和空气源热泵在寒冷地区应用中存在的问题,研发了一种新型复合蒸发器,将平板微热管阵列太阳能光伏光热(PV/T)集热器与空气源热泵相结合,组成新型太阳能-空气复合热源热泵热水系统。并对该热水系统在不同运行工况下的水箱水温、吸排气压力、压缩机功率和性能等进行了实验研究。实验结果表明,在环境温度分别为5、10和15℃的条件下,热泵加热73 L水,水温从15℃加热到50℃时,双热源运行工况的加热时间比单空气热源运行工况依次缩短了5.14%、10.29%和11.38%,COP依次提高了5.99%、9.28%和11.96%。

  3. An Approach to the Integrated Design of PCM-Air Heat Exchangers Based on Numerical Simulation: A Solar Cooling Case Study

    Directory of Open Access Journals (Sweden)

    Pablo Dolado

    2015-10-01

    Full Text Available A novel technique of design of experiments applied to numerical simulations is proposed in this paper as a methodology for the sizing and design of thermal storage equipment integrated in any specific application. The technique is carried out through the response surfaces in order to limit the number of simulation runs required to achieve an appropriate solution. Thus, there are significant savings on the time spent on the design as well as a potential cost saving on the experimentation if similarity relationships between the prototype and the model are met. The technique is applied here to a previously developed and validated numerical model that simulates the thermal behavior of a phase change material-air heat exchanger. The incorporation of the thermal energy storage unit is analyzed in the case of a solar cooling application, improving the system coefficient of performance. The economic viability is mainly conditioned by the price of the macroencapsulated phase change material.

  4. Heat transfer and friction factor characteristics using continous M shape ribs turbulators at different orientation on absorber plate solar air heater

    Energy Technology Data Exchange (ETDEWEB)

    Chaudhary, Sachin; Varun [Department of Mechanical Engineering, NIT Hamipur-177005 (India); Chauhan, Manish Kumar [Department of Mechanical Engineering, College of Engineering Roorkee, Roorkee-247667 (India)

    2012-07-01

    This paper having more concern with enhancement of heat transfer coefficient using artificial roughened absorber plate on solar air heater. The increment in heat transfer also leads to increase in friction factor which leads to increase in pumping power. In this study M shape geometry has been studied which is having different orientation. The effect of roughness parameters relative roughness height (e/D), relative roughness (P/e) and angle of attack (?) on Nusselt number and friction factor have been seen. The range of Reynolds number 3000-22000, e/D, P/e and ? are 0.037-0.0776, 12.5-75 and 30-60{sup o} respectively.. It has been found out that providing the artificial roughness of M shape increases heat transfer up to 1.7-1.8 times over the smooth duct.

  5. The influences of recycle on performance of baffled double-pass flat-plate solar air heaters with internal fins attached

    Energy Technology Data Exchange (ETDEWEB)

    Ho, C.D.; Yeh, H.M.; Cheng, T.W.; Chen, T.C.; Wang, R.C. [Energy and Opto-Electronic Materials Research Center, Department of Chemical and Materials Engineering, Tamkang University Tamsui, Taipei 251 (China)

    2009-09-15

    A new device for inserting an absorber plate to divide a flat-plate channel into two parts with fins attached by baffles and external recycling at the ends is presented. The proposed device substantially improves the heat-transfer efficiency. Experimental and theoretical investigations into the device efficiency are presented. The theoretical prediction agreement with the measured values from the experimental results is good. The experimental and theoretical results are represented graphically and compared with data from the downward-type single-pass solar air heaters of the same size without recycling. Considerable heat-transfer improvement is obtained by employing baffled double-pass operations with external recycling and fin attached over and under the absorber plate. The recycle ratio and absorber plate location influences on the heat-transfer efficiency and on the power consumption increment are also discussed. (author)

  6. Penambahan Urea sebagai Co-Substrat pada Sistem High Rate Algae Reactor (HRAR) untuk Pengolahan Air Limbah Tercemar Minyak Solar

    OpenAIRE

    Ayu Syarifa Darwinastwantya; Agus Slamet; Joni Hermana

    2014-01-01

    Kebutuhan bahan bakar minyak di Indonesia semakin meningkat. Peningkatan tersebut mengakibatkan eksplorasi dan pengolahan secara berlebihan. Eksplorasi dan pengolahan berlebihan akan memberikan dampak buruk bagi lingkungan, yaitu limbah. Limbah minyak bumi biasanya langsung dibuang ke lingkungan yang dapat menyebakan pencemaran lingkungan, misalnya air. Pengolahan limbah menggunakan alga dapat digunakan sebagai pengolahan lanjutan tanpa menimbulkan polusi tambahan. Penelitian ini bertujuan u...

  7. CFD Analysis to Study Effect of Circular Vortex Generator Placed in Inlet Section to Investigate Heat Transfer Aspects of Solar Air Heater

    Directory of Open Access Journals (Sweden)

    Vipin B. Gawande

    2014-01-01

    Full Text Available CFD analysis of 2-dimensional artificially roughened solar air heater duct with additional circular vortex generator, inserted in inlet section is carried out. Circular transverse ribs on the absorber plate are placed as usual. The analysis is done to investigate the effect of inserting additional vortex generator on the heat transfer and flow friction characteristics inside the solar air heater duct. This investigation covers relative roughness pitch in the range of 10 ≤ P/e ≤ 25 and relevant Reynolds numbers in the range of 3800 ≤ Re ≤ 18000. Relative roughness height (e/D is kept constant as 0.03 for analysis. The turbulence created due to additional circular vortex generator increases the heat transfer rate and at the same time there is also increase in friction factor values. For combined arrangement of ribs and vortex generator, maximum Nusselt number is found to be 2.05 times that of the smooth duct. The enhancement in Nusselt number with ribs and additional vortex generator is found to be 1.06 times that of duct using ribs alone. The maximum increase in friction factor with ribs and circular vortex generator is found to be 2.91 times that of the smooth duct. Friction factor in a combined arrangement is 1.114 times that in a duct with ribs alone on the absorber plate. The augmentation in Thermal Enhancement Factor (TEF with vortex generator in inlet section is found to be 1.06 times more than with circular ribs alone on the absorber plate.

  8. Research on Solar Steamy Hot-air Drying Technology%太阳能蒸汽热风干燥技术的研究

    Institute of Scientific and Technical Information of China (English)

    裴坤; 孔晓玲; 段凤江; 于鹏

    2012-01-01

    The technology of solar steamy hot-air drying uses the vacuum tube collector to heat water and produce steam, then converted it into hot air through the heat exchanger. The purpose is to realize the drying of agricultural products. This paper develops a set of test device. The experiments of drying carrots were carried out to test the drying system' s performance. The results show that when solar power reaches above 750W/ m2, the steam can stable work for about 5 ~7 hours;The temperature of the dryer's high temperature section can be stabilized at around 551 ,and the temperature of the low can be stabilized at around 40t. The drying effect of carrots is good.%太阳能蒸汽热风干燥技术利用真空集热管对水加热产生的水蒸气,通过换热器转换成热风,实现对农产品的干燥作业.本文研制了一套试验装置,以胡萝卜作为样品进行了干燥机的干燥性能试验,结果表明:当太阳辐射值达到750W/m2以上时,蒸汽可以稳定工作5~7h;干燥室内高温工作段温度可以稳定在55℃左右,低温工作段温度可以稳定在40℃左右.胡萝卜干燥效果良好.

  9. CFD analysis to study effect of circular vortex generator placed in inlet section to investigate heat transfer aspects of solar air heater.

    Science.gov (United States)

    Gawande, Vipin B; Dhoble, A S; Zodpe, D B

    2014-01-01

    CFD analysis of 2-dimensional artificially roughened solar air heater duct with additional circular vortex generator, inserted in inlet section is carried out. Circular transverse ribs on the absorber plate are placed as usual. The analysis is done to investigate the effect of inserting additional vortex generator on the heat transfer and flow friction characteristics inside the solar air heater duct. This investigation covers relative roughness pitch in the range of 10 ≤ P/e ≤ 25 and relevant Reynolds numbers in the range of 3800 ≤ Re ≤ 18000. Relative roughness height (e/D) is kept constant as 0.03 for analysis. The turbulence created due to additional circular vortex generator increases the heat transfer rate and at the same time there is also increase in friction factor values. For combined arrangement of ribs and vortex generator, maximum Nusselt number is found to be 2.05 times that of the smooth duct. The enhancement in Nusselt number with ribs and additional vortex generator is found to be 1.06 times that of duct using ribs alone. The maximum increase in friction factor with ribs and circular vortex generator is found to be 2.91 times that of the smooth duct. Friction factor in a combined arrangement is 1.114 times that in a duct with ribs alone on the absorber plate. The augmentation in Thermal Enhancement Factor (TEF) with vortex generator in inlet section is found to be 1.06 times more than with circular ribs alone on the absorber plate.

  10. Effects on annual cost of solar/air-heat utilization system of carbon tax and interest rate for a residential house; Jutakuyo taiyo/taikinetsu riyo system no nenkan keihi ni oyobosu tansozei kinri no eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Q.; Kenmoku, Y.; Sakakibara, T. [Toyohashi University of Technology, Aichi (Japan); Nakagawa, S. [Maizuru National College of Technology, Kyoto (Japan); Kawamoto, T. [Shizuoka University, Shizuoka (Japan). Faculty of Engineering

    1996-10-27

    In recent years, a system has been proposed that utilizes river heat, air-heat, exhaust heat from a cooler, etc., in addition to natural energy for the heat pump. With the introduction of such system, the amount of energy used and that of CO2 exhaust will be greatly reduced, but annual expenses will be increased as it stands. In order to improve the cost efficiency of the system, a proposal has been made for the introduction of an economic policy such as the carbon tax and a low interest financing system. With these matters in the background, the subject study predicts the production of solar cells in the future and, on the basis of this production, determines the price, conversion efficiency and equipment energy of solar cells in the future. Using these values and taking into consideration the introduction of the carbon tax and the low interest financing system, the optimum area was determined for solar cells and heat concentrators in a future residential solar/air-heat energy system. The carbon tax, being imposed on all CO2 discharges, had a large effect. Moreover, as the tax increased, annual expenses decreased for the solar/air-heat system. 3 refs., 6 figs.

  11. Environmental impact of the programs of substitution of room type air conditioning equipment; Impacto ambiental de los programas de sustitucion de equipos de aire tipo cuarto

    Energy Technology Data Exchange (ETDEWEB)

    Alarcon Aleman, Jose Mauricio [OLADE, Quito (Ecuador)

    2002-09-01

    The present article approaches in a general way the relation that exists between the environment and the saving of electrical energy, especially in the Programs of Demand Side Management (DSM). In particular form the potential environmental impacts are described, derived of the use and the discard of the room type air conditioning equipment, goes deep into the characteristics of their cooling fluids, as well as in the relation that these keep with the protocols of Montreal and Kyoto. Finally, this article comments the incidence which have, the manufacturers as the institutions that implement DSM programs, on the environmental part of the programs of substitution of room type air conditioning equipment. In addition it is briefly described, the pilot program developed by Fideicomiso para el Ahorro de Energia Electrica (FIDE) as a successful case. [Spanish] En forma general, el presente articulo aborda la relacion que existe entre el medio ambiente y el ahorro de energia electrica, especialmente en los Programas de Administracion por el Lado de la Demanda (ALD). En forma particular se describen los impactos ambientales potenciales, derivados del uso y desecho de los equipos de aire acondicionado tipo cuarto, se ahonda en las caracteristicas de sus refrigerantes, asi como en la relacion que estos guardan con los protocolos de Montreal y Kioto. Finalmente, se comenta la incidencia que tienen, tanto los fabricantes como las instituciones que implementan programas de ALD, sobre la parte ambiental de los programas de sustitucion de equipos de aire acondicionado tipo cuarto. Ademas se describe brevemente, el programa piloto desarrollado por el Fideicomiso para el Ahorro de Energia Electrica (FIDE) como un caso exitoso.

  12. Air-Stable and Solution-Processable Perovskite Photodetectors for Solar-Blind UV and Visible Light.

    Science.gov (United States)

    Guo, Yunlong; Liu, Chao; Tanaka, Hideyuki; Nakamura, Eiichi

    2015-02-01

    Stable perovskite CH3NH3PbI3-xClx for a photodetector was prepared through spin-coating of a fluorous polymer as a light protection layer. The best responsivity of photodetector was 14.5 A/W to white light and 7.85 A/W for solar-blind UV light (λ = 254 nm). The response time was in the submicrosecond range. The fluorous polymer coating increases the lifetime of the devices to almost 100 days. PMID:26261975

  13. Design of a Transpired Air Heating Solar Collector with an Inverted Perforated Absorber and Asymmetric Compound Parabolic Concentrator.

    OpenAIRE

    Shams, Nasif

    2013-01-01

    absorber and an asymmetric compound parabolic concentrator was applied to increase the intensity of solar radiation incident on the perforated absorber. A 2D ray tracing model quantified optical efficiency at different incident angles within 27o to 89o incident angles. The beam efficiency was found to vary between 72% and 79% and diffuse efficiency was found to vary between 48.2% and 65%. The average thermal efficiency was found to be approximately 55%-65% with average radiation above 400 W/m...

  14. 并联冷却的太阳能复合式空调节能特性%Energy-saving Character of a Solar Hybrid Air Conditioner with Parallel Condensers

    Institute of Scientific and Technical Information of China (English)

    康靖; 王劲柏

    2015-01-01

    A hybrid solar air-conditioner with consideration of solar energy’s characteristics is proposed in this paper. We use the air conditioner models, which established by steady-state distribution parameters method, to simulate the influence of chilling water temperature obtained by solar assisted cooling system on the hybrid air conditioner operation performance. The air conditioner operation characteristics studied by analyzing the flow rate variation. Through comparison with another kind of basic model, we obtained variation of the thermal efficiency COP, and analyzed the energy saving character of this air conditioner simply.%根据太阳能的特点,提出了一种并联冷却的太阳能复合式空调器,并用稳态分布参数法建立空调器模型,来模拟计算太阳能辅助冷却系统制取的冷水水温变化对复合式空调器运行效果的影响。通过分析制冷剂流量变化研究该空调器的运行特性,并与另一种基本运行模式对比,得到了其热效能COP值的变化情况,并对该空调器的节能特性进行了简单的分析。

  15. 太阳能饲草干燥设备中空气集热器改进设计%Improved Design of Air Collector in Solar Energy Forage Drying Equipment

    Institute of Scientific and Technical Information of China (English)

    杜建强; 杨世昆; 刘贵林; 郭志平

    2012-01-01

    In the improved process of solar energy forage drying equipment, the key component of solar energy forage drying equipment was air heat collector. In order to improve equipment productivity, the structure and working principle of air heater were analyzed. Air heat collecting efficiency was improved. Through the performance experiment, the honeycomb structure of the air collector was very important in the solar energy forage drying equipment. Productivity increased by 20% . The air collector efficiency increased by 50%.%在太阳能饲草干燥设备改进过程中,为提高设备生产率,从太阳能饲草干燥设备的关键部件入手,研究空气集热器的结构和工作原理,进而对空气集热器进行改进,提高空气集热器的集热效率.进行了设备改进的性能对比试验,得出装有蜂窝结构空气集热器的太阳能饲草干燥设备,生产率提高约20%,改进后的空气集热器集热效率提高约50%.

  16. The Application Research of the Solar Energy Combines with Air Source Heat Pump System%太阳能结合空气源热泵系统应用研究

    Institute of Scientific and Technical Information of China (English)

    王文周

    2014-01-01

    太阳能结合空气源热泵系统作为生活热水、低温采暖热源、空调冷源,通过系统智能化优化控制及精准控温运行模式,完全采集太阳能、空气能免费能源,实现了工程上的节能、经济运行。%Solar energy combines with air source heat pump system as domestic hot water, low temperature heat sources for heating, and air conditioning cold source, which achieve the project on energy saving and economic operation through the intel igent optimization control system and precise temperature control operation mode with the completely col ection of solar energy and free air source energy.

  17. Performance Assessment of a Hybrid Solar-Geothermal Air Conditioning System for Residential Application: Energy, Exergy, and Sustainability Analysis

    Directory of Open Access Journals (Sweden)

    Yasser Abbasi

    2016-01-01

    Full Text Available This paper investigates the performance of a ground source heat pump that is coupled with a photovoltaic system to provide cooling and heating demands of a zero-energy residential building. Exergy and sustainability analyses have been conducted to evaluate the exergy destruction rate and SI of different compartments of the hybrid system. The effects of monthly thermal load variations on the performance of the hybrid system are investigated. The hybrid system consists of a vertical ground source heat exchanger, rooftop photovoltaic panels, and a heat pump cycle. Exergetic efficiency of the solar-geothermal heat pump system does not exceed 10 percent, and most exergy destruction takes place in photovoltaic panel, condenser, and evaporator. Although SI of PV system remains constant during a year, SI of GSHP varies depending on cooling and heating mode. The results also show that utilization of this hybrid system can reduce CO2 emissions by almost 70 tons per year.

  18. 基于太阳能辐射技术的热能转换空调制冷技术研究%Research on Cooler Air conditioner Based on Thermal Conversion of Solar Radiation Technology

    Institute of Scientific and Technical Information of China (English)

    李裕斌

    2016-01-01

    This paper presents technical approach on cooler air conditioner based on thermal conver-sion of solar radiation technology,i.e.transforming solar energy to heat energy,and use the heat energy to achieve refrigeration.We developed a new solar absorption air conditioning system based on the thermal conversion of solar radiation technology.Through verification studies,the operating characteristics of so-lar collector and heat storage system of air conditioning systems,and operating characteristics of the re-frigeration unit are verified.The experiment shows:the air conditioning system can operate continuously and stably for 8 hours.The average cooling capacity is 4 kW,and the maximum cooling capacity is 4.7 kW.The system COP average is 0.3.Therefore,this new solar absorption air conditioning system based on thermal conversion of solar radiation technology provides a feasible method to realize large scale,low cost application of solar energy.%给出了以太阳能辐射技术为基础的热能转换空调制冷技术的技术方法,即将太阳能转变成热能,使用热能进行制冷。以太阳能辐射技术的热能转换为基础,研制了新型的太阳能吸收式空调系统,并且通过实验研究,验证了该系统的集热、蓄热特性以及制冷机组的运行热性。实验表明,该空调系统可连续8 h 稳定地工作,最大制冷量可达到4.7 kW,平均值也可达到4 kW,该空调系统性能参数 COP,平均可达到0.3。因此,基于太阳能辐射技术的热能转换空调制冷技术为太阳能规模化、低成本应用提供了行之有效的新方法。

  19. Proposal for energy saving in air conditioning equipment; Propuesta para ahorro energetico en acondicionadores de aire

    Energy Technology Data Exchange (ETDEWEB)

    Solis Recendez, Daniel H [Division de Ingenieria Electrica, Universidad Nacional Autonoma de Mexico (Mexico)

    2008-10-15

    In the last decades, the air conditioning systems have become a crucial part in the search from comfort in extreme climates. Nevertheless, they have also become one of the greatest energy consumers. In this article it is proposed that the final conditions that the air conditioning equipment looks for not to be fixed, but variable in respect to a certain comfort zone. This zone is a variation of the used one in the bio-climatic chart of Olgyay that considers the rapidity whereupon the reached conditions tend to leave the comfort zone. It is analyzed how to choose the point on the zone that costs less energy in arriving to it. [Spanish] En las ultimas decadas, los sistemas de aire acondicionado se han vuelto una parte crucial en la busqueda de confort en climas extremosos. Sin embargo, tambien se han vuelto de los mayores consumidores de energia. En este articulo se propone que las condiciones finales que busquen lograr los acondicionadores no sean fijas, si no variables respecto a una determinada zona de confort. Dicha zona es una variacion de la utilizada en la carta bioclimatica de Olgyay, que considera la rapidez con que las condiciones alcanzadas tienden a abandonar la zona de confort. Se discute como elegir el punto sobre la zona que cueste menos energia en llegara el.

  20. 一种新型渗透式太阳能空气集热器的热性能研究%An Investigation on Heat Performance of a Novel Transpired Solar Air Collector

    Institute of Scientific and Technical Information of China (English)

    张欢; 高煜; 由世俊; 李宪莉

    2012-01-01

    设计制作了一种新型平板型、渗透式太阳能空气集热器,介绍了该集热器的结构、尺寸及工作原理,并以该集热器为研究对象,建立了数学模型,进行了实验测试.结果表明,在辐射水平较高且稳定、风速较小的测试条件下,该集热器的性能稳定,集热效率和出风温度较高,具有一定的推广与应用潜力;同时,所建数学模型准确可靠,可用来对集热器进行模拟分析.%A novel flat-plate and transpired solar air collector was designed and constructed, and the structure, size and working mechanism of the collector were introduced. Taking the collector as an object, the mathematical model was developed, and the experiment was carried out. Under the condition of high solar radiation intensity and low wind velocity, results show that the performance of the novel solar air collector is stable, and the output temperature and thermal efficiency are high enough to make the collector have a good prospect of popularization and application, and the mathematical model is accurate enough to analyze the novel solar air collector.

  1. Properties of the Carrol system and a machine design for solar-powered, air cooled, absorption space cooling

    Science.gov (United States)

    1981-05-01

    The name Carrol was selected as a convenient shorthand designation for a prime candidate chemical system comprising ethylene glycol-lithium bromide as an absorbent mixture with water as a refrigerant. The instrumentation, methods of handling data and numerical results from a systematic determination of Carrol property data required to design an air cooled absorption machine based on this chemical system are described. These data include saturation temperature, relative enthalpy, density, specific heat capacity, thermal conductivity, viscosity and absorber film heat transfer coefficient as functions of solution temperature and Carrol concentration over applicable ranges. For each of the major components of the absorption chiller, i.e., generator, chiller, absorber, condenser, heat exchanger, purge and controls, the report contains an assembly drawing and the principal operating characteristics of that component.

  2. THE RESEARCH OF TEST METHODS FOR THE THERMAL PERFORMANCE OF SOLAR AIR COLLECTORS%太阳能空气集热器热性能测试方法研究

    Institute of Scientific and Technical Information of China (English)

    孙峙峰; 曲世琳

    2011-01-01

    It is established the mathematical model and given test methods for the thermal performance of solar air collectors on the basis of both at home and abroad standards and documents. And the practical test was done at the National Center of Quality Supervision and Testing for Solar Heating System (Beijing) according the test methods and test results were analyzed. In this study, test methods for the thermal performance of solar air collectors which appropriate to the level of China' s solar air collector quality were given. It is a good technology and experimental reserves for constituting the national test standards for the thermal performance of solar air collectors.%在参考国内外标准和文献资料的基础上,建立太阳能空气集热器的测试数学模型,给出太阳能空气集热器热性能测试的试验方法,在国家太阳能热水器质量监督检验中心(北京)的实验室进行太阳能空气集热器实际测试,并对测试结果进行分析.给出适合我国太阳能空气集热器质量水平的太阳能空气集热器热性能测试方法,为制定我国太阳能空气集热器热性能测试国家标准做技术和实验储备.

  3. Studies of flat-plate solar air collectors with absorber plates made of amorphous silicon photovoltaic modules; Amorphous taiyo denchi module wo shunetsuban to shita heibangata kukishiki shunetsuki no kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Sato, K.; Ito, S.; Miura, N. [Kanagawa Institute of Technology, Kanagawa (Japan)

    1996-10-27

    A light/heat hybrid air type heat collector has been developed in which heat is collected by solar cell panels. In Type 1 heat collector provided with a glass cover, two modules are connected in series and placed under a glass cover to serve as a heat collecting plate, each module built of a steel plate and two thin-film amorphous solar cells bonded to the steel plate. Air runs under the heat collecting plate. Type 2 heat collector is a Type 1 heat collector minus the glass cover. Air is taken in by a fan, runs in a vinyl chloride tube, and then through the heat collector where it is heated by the sun, and goes out at the exit. Heat collecting performance was subjected to theoretical analysis. This heat collector approximated in point of heat collection a model using a board painted black, which means that the new type functions effectively as an air-type heat collector. Operating as a photovoltaic power generator, the covered type generated approximately 20% less than the uncovered type under 800W/m{sup 2} insolation conditions. Type 1 has been in service for five months, and Type 2 for 2 months. At present, both are free of troubles such as deformation and the amorphous solar cell modules have deteriorated but a little. 4 refs., 9 figs.

  4. EVALUACIÓN DE ALTERNATIVAS PARA CLIMATIZACIÓN DE ESTANQUES CON ENERGÍA SOLAR PARA CULTIVO DE TILAPIA ROJA (Oreochromis sp, LOCALIZADOS EN LA ZONA FRÍA DEL VALLE DEL CAUCA, COLOMBIA EVALUATION OF ALTERNATIVES FOR AIR CONDITIONING OF PONDS WITH SOLAR ENERGY FOR CULTIVATION OF RED TILAPIA (Oreochromis sp, LOCATED IN THE COLD AREA OF THE CAUCA VALLEY, COLOMBIA

    Directory of Open Access Journals (Sweden)

    Francisco Javier Borja Gallardo

    2006-06-01

    Full Text Available La investigación fue desarrollada para que la tilapia roja (Oreochromis sp, especie de pez mÁs producida en Colombia, pueda ser explotada en lugares donde las condiciones óptimas para su normal desarrollo no son las adecuadas, como son las regiones altas con temperaturas por debajo de los 24 °C, aplicando metodologías relacionadas con el aprovechamiento de la energía solar. Las técnicas evaluadas fueron: climatización por medio de colectores solares, climatización por medio de manta térmica, climatización por medio de mangueras térmicas y climatización por medio de resistencias eléctricas. Se analizaron factores como funcionalidad, mantenimiento, limitaciones organizativas, espaciales, y costos.The research was developed so that the red tilapia (Oreochromis sp, fish species that more taken place in Colombia can be exploited in regions where the good conditions for its normal development are not the appropriate ones as in the high regions with temperatures below the 24 °C, applying methodologies related with the use of the solar energy. The evaluated methodologies were: air conditioning by means of solar collectors, air conditioning by means of thermal blanket, air conditioning by means of thermal hoses and air conditioning by means of electric resistances. Factors like functionality, maintenance, organizational and space limitations, and costs were analized.

  5. Solar thermal power systems. Practical guide for heating and air conditioning experts, electricians and roofers, planners and architects, builder-owners and training institutions; Solarthermische Anlagen. Leitfaden fuer SHK-, Elektro- und Dachdeckerhandwerk, fuer Fachplaner und Architekten, Bauherren und Weiterbildungsinstitutionen

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    There is a growing market for solar thermal power systems. Builder-owners, planners, architects, fitters and heating systems experts as well as roofers require knowledge of solar thermal power generation. This includes technical and marketing information as well as the aspects of consulting, projecting, dimensioning, cost structure, and solar marketing. This guide will give decision aids and contribute to quality-minded projecting and installation of solar thermal power systems. The following aspects are discussed: Assembly and mounting, with many details to account for all possible in-situ conditions; Industrial-scale systems and solar district heating systems; Simulation tools, in detail; Solar swimming pool heating and air heating; Practical strategies for successful solar marketing; Market survey of suppliers of solar systems and components. [German] Der Markt fuer die thermische Nutzung der Sonnenenergie entwickelt sich kraeftig. Bauherren, Planer, Architekten, Gas/Wasser- und Heizungsinstallateure sowie Dachdecker werden in zunehmendem Masse mit der Solarthermie in Beruehrung kommen. Dies betrifft nicht nur die Kenntnis ueber den Stand der Technik und die aktuelle Marktsituation, sondern auch die Bereiche Beratung, Planung, Dimensionierung, Kostenstruktur und das Solarmarketing. Der vorliegende Leitfaden will Entscheidungshilfen geben und dazu beitragen, dass solarthermische Anlagen nach dem neuesten Stand der Technik qualitaetsbewusst geplant und sorgfaeltig installiert werden. Im Vergleich zu seinem Vorgaenger wurden im Leitfaden wurden folgende Schwerpunkte bearbeitet: 1 Der Montagebereich wurde erheblich ausgeweitet, um den vielfaeltigen Vor-Ort-Gegebenheiten bei der Installation gerecht zu werden 2 Der Bereich der Grossanlagen bis zu solaren Nahwaermenetzen wurde vertieft 3 Die Simulationswerkzeuge werden detailliert dargestellt 4 Den Anwendungsbereichen solare Schwimmbadwassererwaermung und Luftheizung ist jeweils ein eigenes Kapitel gewidmet worden 5

  6. Thermal performance of new flat plate solar air heater based on micro-heat pipe arrays (MHPA)%微热管阵列式太阳能平板空气集热器集热性能

    Institute of Scientific and Technical Information of China (English)

    朱婷婷; 刁彦华; 赵耀华; 马骋; 李凤飞

    2016-01-01

    In common types of flat-plate solar air heaters, the uneven flow and heat exchange between air and an absorber plate poses a problem. To resolve this problem, this paper proposed a novel type of flat-plate solar air heater based on micro-heat pipe arrays (MHPA). An investigation was carried out on the design, thermal performance and flow resistance characteristic of the novel heater based on micro-heat pipe arrays. The new air collector consists of 15 MHPAs with V-shaped fins attached to the heat release (condenser) section, absorber film, insulation board, bottom plate, and air ventilation and heat exchange section. The components of the heater include the toughened glass cover, air layer (35 mm), MHPA-absorber plate, thermal insulation layer, and the back board. Solar energy is absorbed by the MHPA evaporator section with the organic combination of high efficiency absorber film, which formed a heat pipe effect within each micro heat pipe arrays. The heat has been released to the air in the ventilation and heat exchange section of the heater, whereas the air was eventually warmed. Simultaneously, the working medium in MHPA proceeds continuous phase transition cycle and continuously passes solar radiation heat to air in the air duct with high efficiency. The MHPA heat-absorbing plate core can realize the whole area of heat absorption, high efficient heat transmission, and large surface of heat release. The total solar energy is received by the heater, and some energy is transferred to the air flow in the air duct as useful energy; the remaining energy is lost mainly through the glass cover, frames, bottom plate, and air duct. The heat loss through the frames and the air duct can be ignored because of good heat preservation condition. So the glass cover becomes the main source of heat loss. Thermal analysis shows that heat loss through the glass cover occupies the largest proportion of the total heat loss of the heater.To test the new heater thermal efficiency and

  7. Mars Solar Balloon Lander Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Mars Solar Balloon Lander (MSBL) is a novel concept which utilizes the capability of solar-heated hot air balloons to perform soft landings of scientific...

  8. High-efficiency and air-stable P3HT-based polymer solar cells with a new non-fullerene acceptor

    Science.gov (United States)

    Holliday, Sarah; Ashraf, Raja Shahid; Wadsworth, Andrew; Baran, Derya; Yousaf, Syeda Amber; Nielsen, Christian B.; Tan, Ching-Hong; Dimitrov, Stoichko D.; Shang, Zhengrong; Gasparini, Nicola; Alamoudi, Maha; Laquai, Frédéric; Brabec, Christoph J.; Salleo, Alberto; Durrant, James R.; McCulloch, Iain

    2016-06-01

    Solution-processed organic photovoltaics (OPV) offer the attractive prospect of low-cost, light-weight and environmentally benign solar energy production. The highest efficiency OPV at present use low-bandgap donor polymers, many of which suffer from problems with stability and synthetic scalability. They also rely on fullerene-based acceptors, which themselves have issues with cost, stability and limited spectral absorption. Here we present a new non-fullerene acceptor that has been specifically designed to give improved performance alongside the wide bandgap donor poly(3-hexylthiophene), a polymer with significantly better prospects for commercial OPV due to its relative scalability and stability. Thanks to the well-matched optoelectronic and morphological properties of these materials, efficiencies of 6.4% are achieved which is the highest reported for fullerene-free P3HT devices. In addition, dramatically improved air stability is demonstrated relative to other high-efficiency OPV, showing the excellent potential of this new material combination for future technological applications.

  9. An investigation of heat transfer augmentation and friction characteristics in solar air heater duct with V-shaped wire as artificial roughness on absorber plate

    Energy Technology Data Exchange (ETDEWEB)

    Madhukeshwara, N. [Department of Mechanical Engineering, B.I.E.T, Davanagere, Karnataka (India); Prakash, E.S. [Department of Studies in Mechanical Engineering, U.B.D.T.C.E, Davanagere, Karnataka (India)

    2013-07-01

    An experimental investigation of heat transfer augmentation and friction characteristics of fully developed turbulent flow in a rectangular duct of solar air heater with absorber plate having V-shaped wire ribs as artificial roughness on its underside is carried out. The investigation covers wide range of different parameters of wire ribbed roughness: relative roughness pitch (p/e) from 10 to 40, relative roughness height (e/Dh) from 0.01 to 0.04 and angle of attack of flow from 20° to 90°. Duct aspect ratio (W/B) is kept 5 and Reynolds number (Re) is varied from 2,500 to 8,500. The heat transfer and friction factor values obtained are compared with those of smooth duct under similar flow conditions. Expressions are developed for Nusselt number and friction factor for the roughness geometry. Enhancement of Nusselt number and friction factor for roughened duct are 1.5 and 2.7 times of smooth duct respectively.

  10. Influence of air pressure, humidity, solar radiation, temperature, and wind speed on ambulatory visits due to chronic obstructive pulmonary disease in Bavaria, Germany

    Science.gov (United States)

    Ferrari, Uta; Exner, Teresa; Wanka, Eva R.; Bergemann, Christoph; Meyer-Arnek, Julian; Hildenbrand, Beate; Tufman, Amanda; Heumann, Christian; Huber, Rudolf M.; Bittner, Michael; Fischer, Rainald

    2012-01-01

    Chronic obstructive pulmonary disease (COPD) is one of the most important causes of morbidity and mortality in the world. The disease is often aggravated by periods of increased symptoms requiring medical attention. Among the possible triggers for these exacerbations, meteorological factors are under consideration. The objective of this study was to assess the influence of various meteorological factors on the health status of patients with COPD. For this purpose, the daily number of ambulatory care visits due to COPD was analysed in Bavaria, Germany, for the years 2006 and 2007. The meteorological factors were provided by the model at the European Centre for Medium Range Weather Forecast (ECMWF). For the multivariate analysis, a generalised linear model was used. In Bavaria, an increase of 1% of daily consultations (about 103 visits per day) was found to be associated with a change of 0.72 K temperature, 209.55 of log air surface pressure in Pa, and a decrease of 1% of daily consultations with 1,453,763 Ws m2 of solar radiation. There also seem to be regional differences between north and south Bavaria; for instance, the effect of wind speed and specific humidity with a lag of 1 day were only significant in the north. This study could contribute to a tool for the prevention of exacerbations. It also serves as a model for the further evaluation of the impact of meteorological factors on health, and could easily be applied to other diseases or other regions.

  11. High-efficiency and air-stable P3HT-based polymer solar cells with a new non-fullerene acceptor

    KAUST Repository

    Holliday, Sarah

    2016-06-09

    Solution-processed organic photovoltaics (OPV) offer the attractive prospect of low-cost, light-weight and environmentally benign solar energy production. The highest efficiency OPV at present use low-bandgap donor polymers, many of which suffer from problems with stability and synthetic scalability. They also rely on fullerene-based acceptors, which themselves have issues with cost, stability and limited spectral absorption. Here we present a new non-fullerene acceptor that has been specifically designed to give improved performance alongside the wide bandgap donor poly(3-hexylthiophene), a polymer with significantly better prospects for commercial OPV due to its relative scalability and stability. Thanks to the well-matched optoelectronic and morphological properties of these materials, efficiencies of 6.4% are achieved which is the highest reported for fullerene-free P3HT devices. In addition, dramatically improved air stability is demonstrated relative to other high-efficiency OPV, showing the excellent potential of this new material combination for future technological applications.

  12. High-efficiency and air-stable P3HT-based polymer solar cells with a new non-fullerene acceptor

    Science.gov (United States)

    Holliday, Sarah; Ashraf, Raja Shahid; Wadsworth, Andrew; Baran, Derya; Yousaf, Syeda Amber; Nielsen, Christian B.; Tan, Ching-Hong; Dimitrov, Stoichko D.; Shang, Zhengrong; Gasparini, Nicola; Alamoudi, Maha; Laquai, Frédéric; Brabec, Christoph J.; Salleo, Alberto; Durrant, James R.; McCulloch, Iain

    2016-01-01

    Solution-processed organic photovoltaics (OPV) offer the attractive prospect of low-cost, light-weight and environmentally benign solar energy production. The highest efficiency OPV at present use low-bandgap donor polymers, many of which suffer from problems with stability and synthetic scalability. They also rely on fullerene-based acceptors, which themselves have issues with cost, stability and limited spectral absorption. Here we present a new non-fullerene acceptor that has been specifically designed to give improved performance alongside the wide bandgap donor poly(3-hexylthiophene), a polymer with significantly better prospects for commercial OPV due to its relative scalability and stability. Thanks to the well-matched optoelectronic and morphological properties of these materials, efficiencies of 6.4% are achieved which is the highest reported for fullerene-free P3HT devices. In addition, dramatically improved air stability is demonstrated relative to other high-efficiency OPV, showing the excellent potential of this new material combination for future technological applications. PMID:27279376

  13. Enhancing performance and uniformity of CH3NH3PbI3−xClx perovskite solar cells by air-heated-oven assisted annealing under various humidities

    OpenAIRE

    Qing Zhou; Zhiwen Jin; Hui Li; Jizheng Wang

    2016-01-01

    To fabricate high-performance metal-halide perovskite solar cells, a thermal annealing process is indispensable in preparing high quality perovskite film. And usually such annealing is performed on hot plate. However hot-plate annealing could cause problems such as inhomogeneous heating (induced by non-tight contact between the sample and the plate), it is also not fit for large scale manufactory. In this paper, we conduct the annealing process in air-heated oven under various humidity enviro...

  14. Study on a Flat Plate Solar Air Collector with Baffles%扰流板型太阳能平板空气集热器集热性能

    Institute of Scientific and Technical Information of China (English)

    夏佰林; 赵东亮; 代彦军; 李勇

    2011-01-01

    对一种扰流板型太阳能平板空气集热器的集热性能进行了研究,并对各种影响集热器热性能的因素进行了分析,揭示了总热损失系数、扰流板肋片效率、流道内空气流速和扰流板的间距对效率因子和热迁移因子的影响机理.获得了扰流板型太阳能平板空气集热器的集热效率理论表达式,为此类太阳能空气集热器的设计及应用提供了参考.%A flat plate solar air collector with baffles was studied. Several factors that have influence on the thermal performance of the solar collectors were analyzed. The paper investigated the relations between the efficiency factor, the heat-removal factor of the solar air collector and the total heat loss coefficient, baffles fin efficiency, air velocity inside the flow channel, the space between baffles, and the height of baffles. Also, the time constant of the collectors was studied. The theoretical formula of the collector's thermal efficiency was obtained, which can be used for design and application of such kind of collectors.

  15. Comportamento pós-colheita de mamões Formosa 'Tainung 01' acondicionados em diferentes embalagens para o transporte Post harvest behavior of Papaya Formosa 'Tainung 01' conditioned in different packings for transportation

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Magalhães dos Santos

    2008-06-01

    Full Text Available O objetivo deste trabalho foi avaliar a comportamento pós-colheita de mamões do grupo Formosa híbrido 'Tainung 01', submetidos a diferentes formas de acondicionamento para o transporte rodoviário, desde o local da produção até o mercado atacadista. Foram utilizados mamões colhidos nos estádios 1 (até 10% da área superficial da casca com cor amarela e 3 (25 a 40% da área superficial da casca com cor amarela, acondicionados sob diferentes formas: a granel, em caixas de madeira, em caixas de papelão ondulado e em caixas plásticas forradas com plástico-bolha (controle, e transportados a Viçosa-MG, distante 750 km da produção, onde os frutos foram avaliados. Após seleção e novo acondicionamento, os frutos foram armazenamento a 24,5 ± 2ºC por 8 dias, com amostragens a cada 2 dias, para avaliação de índice de cor da casca, perda de massa fresca, taxa respiratória, firmeza da polpa e o índice de injúrias mecânicas. Os resultados evidenciaram os efeitos depreciativos das injúrias mecânicas na qualidade final do mamão, sendo que o transporte de frutos a granel, em relação ao controle, promoveu alterações na qualidade pós-colheita dos frutos, com aumento do índice de cor da casca, redução na firmeza da polpa, elevada perda de massa fresca e taxa respiratória, e maiores percentagens de área da casca injuriada, nos dois estádios de coloração estudados (1,14 e 1,21%, respectivamente. As caixas de papelão ondulado e caixas plásticas forradas com plástico-bolha mantiveram baixa a percentagem de área injuriada em relação aos transportados a granel, constituindo-se em alternativas promissoras na manutenção da qualidade pós-colheita de mamão Formosa destinado ao mercado interno.The aim of this study was to evaluate the post harvest behavior of papaya from the hybrid group Formosa 'TAINUNG 01' stored in different packages for road transportation, from the farm to the wholesale market. It was used papaya picked

  16. Fundamentals of Solar Heating. Correspondence Course.

    Science.gov (United States)

    Sheet Metal and Air Conditioning Contractors National Association, Vienna, VA.

    This course is designed for the use of employees of the air conditioning industry, and offers supervised correspondence instruction about solar technology. The following aspects of applied solar technology are covered: solar heating and cooling, solar radiation, solar collectors, heat storage control devices and specialty items, sizing solar…

  17. Solar photoelectro-Fenton degradation of the antibiotic metronidazole using a flow plant with a Pt/air-diffusion cell and a CPC photoreactor

    International Nuclear Information System (INIS)

    Highlights: • Degradation of metronidazole solutions at pH 3.0 by EF and SPEF in a flow plant. • High recalcitrance of the antibiotic and its products to be destroyed by ·OH radicals. • Only 53% mineralization by the most potent SPEF process at 55.4 mA cm−2. • 5 heterocyclic products, 12 hydroxylated derivatives and 2 carboxylic acids were found. • Release of NO3− ion and generation of persistent N-products and N-volatile species. - Abstract: The degradation of 10 dm3 of solutions of the heterocyclic antibiotic metronidazole in 0.10 mol dm−3 Na2SO4 of pH 3.0 has been comparatively studied by electro-Fenton (EF) and solar photoelectro-Fenton (SPEF). Experiments were performed in a solar flow plant equipped with a Pt/air-diffusion cell and coupled to a compound parabolic collector (CPC) photoreactor. A very weak mineralization was found for the EF process in the dark, indicating a large recalcitrance of heterocyclic compounds to be destroyed by hydroxyl radicals formed at the Pt anode from water oxidation and mainly in the bulk from Fenton's reaction between added Fe2+ and cathodically generated H2O2. The quick photolysis of intermediates by UV radiation from sunlight enhanced largely the mineralization process by SPEF. The effect of applied current density and Fe2+ and drug contents on the SPEF treatment was examined. The best process was found for 1.39 mmol dm−3 metronidazole with 0.50 mmol dm−3 Fe2+ at 55.4 mA cm−2 giving 53% mineralization, 36% mineralization current efficiency and 0.339 kWh (g DOC)−1 in 300 min. Metrodinazole was completely removed and its decay obeyed a pseudo-first-order kinetics. LC-MS analysis allowed identifying five heterocyclic products and twelve hydroxylated derivatives. Ion-exclusion HPLC analysis revealed that final oxalic and oxamic acids were practically removed at the end of electrolysis due to the efficient photolysis of their Fe(III) complexes by sunlight. The initial N of metronidazole gave NO3

  18. Effect of circularity of perforation holes in V-shaped blockages on heat transfer and friction characteristics of rectangular solar air heater duct

    International Nuclear Information System (INIS)

    Highlights: • Effect of perforation shapes of blocks on heat transfer has been investigated. • A new parameter, circularity which represents perforation shape is proposed. • Effect of angle of attack of V-blocks on heat transfer has been investigated. • Nusselt number and friction factor correlations have been developed. - Abstract: The effect of non-circular perforation holes in term of circularity of V-shaped blockages attached to one heated wall of a rectangular duct of solar air heater. Five different hole shapes ranging from circular to square to rectangular in the circularity range of 1–0.6 have been used with varying relative pitch of 4–12, relative blockage height of 0.4–1.0, open area ratio of 5–25% and angle of attack of 30–75° and Reynolds number of flow was varied between 2000 and 20,000. It has been found that there exists an optimum non-circular shape of perforation holes that yields maximum value of Nusselt number; a perfectly circular hole performs substantially inferior as compared to a non-circular hole of considerable non-circularity (ψ = 0.69). An improvement of Nusselt number value in the ratio of 1.13 has been found when circular perforation holes are replaced by rectangular holes of circularity of 0.69. Correlations of Nusselt number as well of friction factor are established in term of Reynolds number and geometrical parameters of blockages which can be used to predict the values of Nusselt number and friction factor with considerably good accuracy

  19. 国内外太阳能空调研究现状及展望%Domestic and International Research Status and Prospects of Solar-driven Air-conditioning

    Institute of Scientific and Technical Information of China (English)

    谭军毅; 余国保; 舒水明

    2013-01-01

    Solar-driven air-conditioning can reduce energy consumption significantly and integrate the utilization devices of solar energy and buildings. It is environmentally friendly and with as outstanding season compatibility. Various technologies can be employed in solar AC cooling, and the technology converting radiated solar energy to thermal energy with higher temperature and thereafter to cooling capacity is one of the most promising applications in solar-building integration. In this paper, technical features of several utilizations of solar AC are analyzed, and an overview of the research status worldwide is presented to provide references for the development of solar AC products and building integration .%太阳能空调能显著减低建筑能耗,实现太阳能利用装置与建筑一体化,还具有季节匹配性好及环保的优点。实现太阳能空调制冷具有多种技术方式,将太阳能辐射转化为较高温度的热能再转化为冷量是其中最有前途的太阳能建筑一体化利用方式。分析了各种太阳能空调利用方式的技术特点,回顾总结了全球主要太阳能空调的研究现状,为太阳能空调产品的开发和其与建筑一体化结合的实现提供参考。

  20. 空气源热泵辅助供热太阳能干燥系统性能研究%PERFORMANCE ANALYSIS OF A SOLAR ENERGY DRYING SYSTEM IN CONJUNCTION WITH AIR SOURCE HEAT PUMP

    Institute of Scientific and Technical Information of China (English)

    罗会龙; 彭金辉; 张利波; 郭胜惠

    2012-01-01

    A novel solar energy drying system in conjunction with air source heat pump (SEDS-ASHP) was developed to avoid limitation of sole solar drying system. The SEDS-ASHP was put into experimental operation successfully. The performances of the SEDS-ASHP were tested and analyzed. Test results showed that, under the climatic conditions of daily solar radiation being about 15. 3 to 21. 6MJ/m , the solar air collector' s daily efficiency is about 0. 343 to 0. 534. For the air source heat pump unit, the average COP (coefficient of performance) varies within the range of 2.52 to 3.61. Compared with conventional electric dryer, the SEDS-ASHP is energy-saving device.%针对单一的太阳能干燥易受天气影响的缺陷,设计并构建了一种空气源热泵辅助供热的太阳能干燥系统,测试分析了系统的热力性能及干燥能效比.实验测试结果表明:在日总太阳辐射为15.3 ~ 21.6MJ/m2的条件下,太阳能热风干燥子系统的日平均集热效率为0.343 ~0.534,空气源热泵热风干燥子系统的性能系数为2.52~3.61.与常规的干燥系统相比,空气源热泵辅助供热太阳能干燥系统具有较大的节能潜力.

  1. UV-A (315-400 nm) irradiance from measurements at 380 nm for solar water treatment and disinfection. Comparison between model and measurements in Buenos Aires, Argentina and Almeria, Spain

    Energy Technology Data Exchange (ETDEWEB)

    Navntoft, C.; Dawidowski, L. [Unidad de Actividad Quimica, Comision Nacional de Energia Atomica, Av. Gral Paz 1499, B1650KNA San Martin (Argentina)]|[Escuela de Posgrado, Universidad Nacional de San Martin, Peatonal Belgrano 3563, B1650ANQ San Martin (Argentina); Blesa, M.A. [Unidad de Actividad Quimica, Comision Nacional de Energia Atomica, Av. Gral Paz 1499, B1650KNA San Martin (Argentina)]|[Escuela de Posgrado, Universidad Nacional de San Martin, Peatonal Belgrano 3563, B1650ANQ San Martin (Argentina)]|[Consejo Nacional de investigaciones Cientificas y Tecnicas (CONICET), Av. Rivadavia 1917, C1033AAJ Ciudad de Buenos Aires (Argentina); Fernandez-Ibanez, P. [Plataforma Solar de Almeria, Carretera Senes km 4, 04002 Tabernas (Spain); Wolfram, E.A. [Centro de Investigaciones Cientificas y Tecnicas de las Fuerzas Armadas (CITEFA), San Juan Bautista de La Salle 4397, B1603ALO Villa Martelli (Argentina); Paladini, A. [Instituto de Genetica y Biologia Molecular, Vuelta de Obligado 2490, CP 1428, Ciudad de Buenos Aires (Argentina)]|[Consejo Nacional de investigaciones Cientificas y Tecnicas (CONICET), Av. Rivadavia 1917, C1033AAJ Ciudad de Buenos Aires (Argentina)

    2009-02-15

    A linear correlation between UV-A and 380 nm was developed by means of the TUV 4.1 radiative transfer model. The prediction error of the correlation was evaluated with data from Buenos Aires, Argentina, 2001, and from 2006, Almeria, Spain. Percent random mean square error (RMSE%) was calculated for intervals of 10 of solar zenith angles, ranging 4.75% at 20 to 37.70% at 90 in clear days and 22.16% at 20 to 26.17% at 90 for cloudy days in Buenos Aires Argentina, and 1.27% at 20 to 11.27% at 90 for clear days in Almeria, Spain. Clouded days were not assessed with the data from Spain. In Argentina, the UV-A radiometer is located in a rural area and the 380 nm radiometer is located in an urban area 6 km away. Hence the real error of the proposed model is closer to that found in Spain were both measurements were performed at the same site. The objective of the work is to achieve a simple and precise method to assess UV-A availability for environmental applications of solar energy, particularly for solar water treatment, at any desired latitude. (author)

  2. 太阳能单效溴化锂吸收式制冷空调技术研究现状%Research Status of Solar Single-effect Lithium Bromide Absorption Refrigeration and Air Conditioning Technology

    Institute of Scientific and Technical Information of China (English)

    周兴法; 谢应明; 谢振兴

    2014-01-01

    In view of the solar single-effect lithium bromide absorption refrigeration and air conditioning technology , which is used mostly in solar refrigeration technology at present , the solar collectors that are available for solar refrigeration are introduced in detail,large amounts of the cases of experimental study and simulation analysis are enumerated ,and finally a novel solar refrige-ration system with bubble pump is presented .Because of its several advantages such as quiet , small volume, energy conserva-tion,and cooling heat recovery ,it is an important development direction of solar absorption refrigeration system in terms of minia-turization.%针对目前太阳能制冷技术中应用最多的太阳能单效溴化锂吸收式制冷空调技术,介绍各种可用于太阳能制冷空调的集热器,列举大量的太阳能单效溴化锂吸收式制冷空调系统的试验研究和模拟分析的案例,最后提出一个新型太阳能无泵溴化锂吸收式制冷空调系统。该系统具有运行安静、体积小、节能、可回收冷却热等优点,是太阳能吸收式制冷系统小型化的一个重要发展方向。

  3. The hardware design of Control System of the Solar-assisted Air Conditioning for Pure Electric Vehicle%纯电动汽车太阳能辅助空调控制系统的硬件设计

    Institute of Scientific and Technical Information of China (English)

    孙浩; 黄菊花

    2012-01-01

    Pure electric vehicle car battery is the only source of power and very limited,auxiliary equipment reduce power consumption of the driving distance of Pure electric vehicles, especially air conditioning, so development of efficient Pure electric car air- conditioning systems is the key step for electric car can be accepted in business, the car roof is full covered with solar cells, air- conditioning system can increase the cooling capacity , while increasing driving distance of Pure electric vehicles. In this paper, studied solar-assisted air conditioning system to small Pure electric vehicles, designed for the air conditioning control system for Pure electric vehicles to create a more comfortable driving and riding environment.%纯电动汽车车载动力电池是其唯一的动力源且很有限,辅助设备消耗的电能减少了纯电动汽车的续驶里程,尤其是空调,所以开发高效的纯电动汽车空调系统是纯电动汽车能够被市场接受的关键。将纯电动汽车顶盖布满太阳电池,可以使空调系统的制冷能力增强,同时还能增加纯电动汽车的行驶距离。对小型纯电动汽车的太阳能辅助空调系统进行研究,设计出适合该空调的自动控制系统,可为纯电动汽车创造出一个更加舒适的驾驶和乘座环境。

  4. Atomic Layer Deposition of TiO2 for a High-Efficiency Hole-Blocking Layer in Hole-Conductor-Free Perovskite Solar Cells Processed in Ambient Air.

    Science.gov (United States)

    Hu, Hang; Dong, Binghai; Hu, Huating; Chen, Fengxiang; Kong, Mengqin; Zhang, Qiuping; Luo, Tianyue; Zhao, Li; Guo, Zhiguang; Li, Jing; Xu, Zuxun; Wang, Shimin; Eder, Dominik; Wan, Li

    2016-07-20

    In this study we design and construct high-efficiency, low-cost, highly stable, hole-conductor-free, solid-state perovskite solar cells, with TiO2 as the electron transport layer (ETL) and carbon as the hole collection layer, in ambient air. First, uniform, pinhole-free TiO2 films of various thicknesses were deposited on fluorine-doped tin oxide (FTO) electrodes by atomic layer deposition (ALD) technology. Based on these TiO2 films, a series of hole-conductor-free perovskite solar cells (PSCs) with carbon as the counter electrode were fabricated in ambient air, and the effect of thickness of TiO2 compact film on the device performance was investigated in detail. It was found that the performance of PSCs depends on the thickness of the compact layer due to the difference in surface roughness, transmittance, charge transport resistance, electron-hole recombination rate, and the charge lifetime. The best-performance devices based on optimized TiO2 compact film (by 2000 cycles ALD) can achieve power conversion efficiencies (PCEs) of as high as 7.82%. Furthermore, they can maintain over 96% of their initial PCE after 651 h (about 1 month) storage in ambient air, thus exhibiting excellent long-term stability. PMID:27340730

  5. Hybrid utilization of solar energy. Part 2. Performance analyses of heating system with air hybrid collector; Taiyo energy no hybrid riyo ni kansuru kenkyu. 2. Kuki shunetsu hybrid collector wo mochiita danbo system no seino hyoka

    Energy Technology Data Exchange (ETDEWEB)

    Yoshinaga, M.; Okumiya, M. [Nagoya University, Nagoya (Japan)

    1996-10-27

    For the effective utilization of solar energy at houses, a heating system using an air hybrid collector (capable of simultaneously performing heat collection and photovoltaic power generation). As the specimen house, a wooden house of a total floor area of 120m{sup 2} was simulated. Collected air is fanned into a crushed stone heat accumulator (capable of storing one day`s collection) or into a living room. The output of solar cell arrays is put into a heat pump (capable of handling a maximum hourly load of 36,327kJ/h) via an inverter so as to drive the fan (corresponding to average insolation on the heat collecting plate of 10.7MJ/hm{sup 2} and heat collecting efficiency of 40%), and shortage in power if any is supplied from the system interconnection. A hybrid collector, as compared with the conventional air collector, is lower in thermal efficiency but the merit that it exhibits with respect to power generation is far greater than what is needed to counterbalance the demerit. When the hybrid system is in heating operation, there is an ideal heat cycle of collection, accumulation, and radiation when the load is light, but the balance between accumulation and radiation is disturbed when the load is heavy. 4 refs., 8 figs., 3 tabs.

  6. Atomic Layer Deposition of TiO2 for a High-Efficiency Hole-Blocking Layer in Hole-Conductor-Free Perovskite Solar Cells Processed in Ambient Air.

    Science.gov (United States)

    Hu, Hang; Dong, Binghai; Hu, Huating; Chen, Fengxiang; Kong, Mengqin; Zhang, Qiuping; Luo, Tianyue; Zhao, Li; Guo, Zhiguang; Li, Jing; Xu, Zuxun; Wang, Shimin; Eder, Dominik; Wan, Li

    2016-07-20

    In this study we design and construct high-efficiency, low-cost, highly stable, hole-conductor-free, solid-state perovskite solar cells, with TiO2 as the electron transport layer (ETL) and carbon as the hole collection layer, in ambient air. First, uniform, pinhole-free TiO2 films of various thicknesses were deposited on fluorine-doped tin oxide (FTO) electrodes by atomic layer deposition (ALD) technology. Based on these TiO2 films, a series of hole-conductor-free perovskite solar cells (PSCs) with carbon as the counter electrode were fabricated in ambient air, and the effect of thickness of TiO2 compact film on the device performance was investigated in detail. It was found that the performance of PSCs depends on the thickness of the compact layer due to the difference in surface roughness, transmittance, charge transport resistance, electron-hole recombination rate, and the charge lifetime. The best-performance devices based on optimized TiO2 compact film (by 2000 cycles ALD) can achieve power conversion efficiencies (PCEs) of as high as 7.82%. Furthermore, they can maintain over 96% of their initial PCE after 651 h (about 1 month) storage in ambient air, thus exhibiting excellent long-term stability.

  7. Solar maximum: solar array degradation

    International Nuclear Information System (INIS)

    The 5-year in-orbit power degradation of the silicon solar array aboard the Solar Maximum Satellite was evaluated. This was the first spacecraft to use Teflon R FEP as a coverglass adhesive, thus avoiding the necessity of an ultraviolet filter. The peak power tracking mode of the power regulator unit was employed to ensure consistent maximum power comparisons. Telemetry was normalized to account for the effects of illumination intensity, charged particle irradiation dosage, and solar array temperature. Reference conditions of 1.0 solar constant at air mass zero and 301 K (28 C) were used as a basis for normalization. Beginning-of-life array power was 2230 watts. Currently, the array output is 1830 watts. This corresponds to a 16 percent loss in array performance over 5 years. Comparison of Solar Maximum Telemetry and predicted power levels indicate that array output is 2 percent less than predictions based on an annual 1.0 MeV equivalent election fluence of 2.34 x ten to the 13th power square centimeters space environment

  8. Analysis and design of a dish/Stirling system for solar electric generation with a 2.7 kW air-cooled engine; Analisis y diseno de un sistema de generacion electrica termosolar con concentrador de disco parabolico y motor Stirling de 2.7 kW enfriado por aire

    Energy Technology Data Exchange (ETDEWEB)

    Beltran-Chacon, R.; Velazquez-Limon, N. [Universidad Autonoma de Baja California, Baja California (Mexico)]. E-mails: rbeltran1@uabc.edu.mx; nicolas.velazquez@uabc.edu.mx; Sauceda-Carvajal, D. [Universidad Politecnica de Baja California, Baja California (Mexico)]. E-mail: dsaucedac@upbc.edu.mx

    2012-01-15

    This paper presents a mathematical modeling, simulation and design of a solar power system of a parabolic dish with an air-cooled Stirling engine of 2.7 kW. The model used for the solar concentrator, the cavity and the Stirling engine were successfully validated against experimental data. Based on a parametric study, the design of the components of the engine is carried out. The study shows that as system capacity increases, the overall efficiency is limited by the power required by the fan, since the design of the cooler needs greater amounts of heat removal by increasing the air flow without affecting the internal conditions of the process (mass flow of working gas and internal dimensions of the same). The system was optimized and achieves an overall efficiency of solar to electric energy conversion of 26.7%. This study shows that the use of an air-cooled Stirling engine is potentially attractive for power generation at low capacities. [Spanish] Este trabajo presenta un modelado matematico, la simulacion y diseno de un sistema de generacion electrica termosolar de disco parabolico con motor Stirling de 2.7 kW enfriado directamente por aire. El modelo utilizado para el concentrador, la cavidad y el motor Stirling, fueron validados satisfactoriamente con datos experimentales. Con base en un estudio parametrico se realizo el dimensionamiento de los componentes del motor. El estudio realizado muestra que conforme se incrementa la capacidad del sistema, la eficiencia global se ve limitada por la potencia requerida por el ventilador, dado que el diseno del enfriador necesita retirar mayores cantidades de calor aumentando el flujo de aire, sin afectar las condiciones internas del proceso (flujo masico del gas de trabajo y dimensiones internas del mismo). El sistema fue optimizado obteniendo una eficiencia global de conversion de energia solar a electrica de 26.7%. Este estudio muestra que el uso de un motor Stirling enfriado directamente por aire es potencialmente

  9. Discussion of the Integrate Designs between Solar Energy Water Heating System and Air-source Heat Pump%空气源热泵与太阳能热水系统集成设计探讨

    Institute of Scientific and Technical Information of China (English)

    王伟; 南晓红; 马俊; 李飞

    2011-01-01

    对不同地区应用的几种不同形式空气源热泵辅助型太阳能热水系统设计方案进行介绍探讨,并以其为基础提出一种新的空气源热泵与太阳能热水系统集成的多功能系统设计方案。总结了不同地区、不同形式空气源热泵辅助型太阳能热水系统的设计方案、特点及新集成系统运行模式等,为我国不同地区应用此类系统时选择具体设计方案提供参考。%In this paper,different designs of the solar energy water heating system aided by air-source heat pump(SEWH-ASHP) are introduced and discussed,then a new integrate design between solar energy water heating system and air-source heat pump is given.Characters of different designs of the solar energy water heating system aided by air-source heat pump in different area are summed and the operational modes of the integrate system are analysed,which would be a useful reference to chose for designing and using the system of SEWH-ASHP and integrate system in different areas in China.

  10. Engineering Design and Economic Analysis of Air Source Heat Pump Assisted Solar Water Heating System%热泵+太阳能热水系统的工程设计与经济分析

    Institute of Scientific and Technical Information of China (English)

    李永华

    2013-01-01

    以空气源热泵为辅助热源的太阳能集中热水系统,不仅节能效率高,而且能保证全天候连续热水供应,是近年来太阳能利用的发展方向之一。淮海工学院学生浴室采用了空气源热泵辅助太阳能热水系统,设计用水人数17000人,日需热水量184 t。介绍了该热水系统的工作原理及设计计算,并对5种热水工程方案从初期投资和运行费用方面进行了详细的经济性分析,结果表明:以空气源热泵为辅助热源的热水方案较其他方案具有更好的经济、环保效益。%The high energy-efficient solar energy water heating system in conjunction with air source heat pump, supplying all-weather continuous hot water, is one of the developing direction of solar energy utilization in recent years. Students ’ Bathroom of Huaihai Institute of Technology use solar water heating system assisted with air source heat pump for 17000 students, requiring 184 tons of hot water every day. The working principle and design calculation of hot water system are expounded with detailed analysis of the initial investment and operating costs for five kinds of heating water engineering solutions. Results show that air source heat pump as auxiliary heat source has better economic and environmental benefits.

  11. 香蕉太阳能热风真空组合干燥设备设计%Design of Solar Hot-air Vacuum Combination Drying Device for Bananas

    Institute of Scientific and Technical Information of China (English)

    童亚子; 杨福孙

    2014-01-01

    为了缩短香蕉的干燥时间,降低干燥成本,将太阳能技术、真空技术和自动控制技术相结合,提出了一种能耗低、干燥效率高且能最大限度保存香蕉中各种生理活性营养成分和风味的香蕉太阳能热风真空组合干燥设备。该设备主要由空气预热器、智能控制器、太阳能热水器、真空泵、干燥箱、热风辅助加热器和引风机等组成,并通过理论计算、分析及实验,验证了该设备的科学性。该设备的成功设计对我国热带等地区的香蕉干燥具有积极的影响作用。%In order to shorten banana drying time and reduce drying costs ,low energy consumption ,high efficiency drying and keeping various physiological active nutrients in bananas of Solar Hot -air vacuum combination drying Device was pro-posed , which combined solar technology , vacuum technology with automatic control technology .The device contains air preheated , intelligent controller , solar water heater , vacuum pump , oven , hot-air auxiliary heater , fan and other compo-nents .According to theoretical analysis and experimental , the device is scientific .The successful design of the device plays a positive impact which dried banana in tropical area of China .

  12. Solar thermal energy / exhaust air heat pump / wood pellet furnace for a sustainable heat supply of low energy buildings in older buildings; Solarthermie / Abluft-Waermepumpe / Pelletofen. Kombisysteme zur nachhaltigen Waermeversorgung von Niedrigenergiehaeusern im Gebaeudebestand

    Energy Technology Data Exchange (ETDEWEB)

    Diefenbach, Nikolaus; Born, Rolf [Institut Wohnen und Umwelt GmbH, Darmstadt (Germany); Staerz, Norbert [Ingenieurbuero inPlan, Pfungstadt (Germany)

    2009-11-13

    The research project under consideration reports on combination systems for a sustainable heat supply for low-energy buildings in older building. For this, a central and decentralized system configuration consisting of solar thermal energy, exhaust air heat pump and wood pellet furnace are presented. Solutions for an interaction of these three heat suppliers in one plant are designated regarding the control strategy. The fundamentals of the computerized simulations for the central and decentralized system are presented. A cost estimate with both variants of the combination system as well as a comparison with conventional energy-saving heat supply systems follow.

  13. Air Conditioner/Dehumidifier

    Science.gov (United States)

    1986-01-01

    An ordinary air conditioner in a very humid environment must overcool the room air, then reheat it. Mr. Dinh, a former STAC associate, devised a heat pipe based humidifier under a NASA Contract. The system used heat pipes to precool the air; the air conditioner's cooling coil removes heat and humidity, then the heat pipes restore the overcooled air to a comfortable temperature. The heat pipes use no energy, and typical savings are from 15-20%. The Dinh Company also manufactures a "Z" coil, a retrofit cooling coil which may be installed on an existing heater/air conditioner. It will also provide free hot water. The company has also developed a photovoltaic air conditioner and solar powered water pump.

  14. 空气源热泵辅助型太阳能热水系统标准的探讨%Research on Specifications of Air Source Heat Pump Assisted Domestic Solar Water Heating Systems

    Institute of Scientific and Technical Information of China (English)

    徐言生; 何钦波; 陈学锋; 李锡宇

    2013-01-01

    The Specifications of Air Source Heat Pump Assisted Domestic Solar Water Heating Systems have stipulated a certain range of variations on the mean environment temperature and the amount of solar radiation in the coefficient of performance (COP) testing of whole unit. In order to research the influence of the variations on COP, the performance testing was divided into two phases. The test of solar water heating system was performed outdoors. The test of air source heat pump heating was performed in an environmental test chamber whose temperature could be adjusted. The experimental results show that the variations in the mean environment temperature and the amount of solar radiation had a great influence on the COP of air source heat pump assisted domestic solar water heating systems. The variation of the COP of the whole unit was minor with the influence of the mean environment temperature and the amount of solar radiation on the solar water heating system performance. But the maximum change of the COP of the whole unit could reach 40%with the influence of the mean environment temperature on the air source heat pump performance. Hence, the amending advice on the testing methods and conditions of the specifications were presented.%《家用空气源热泵辅助型太阳能热水系统技术条件》中对整机综合制热性能系数(COP)试验的平均环境温度和全天太阳能辐照量给出了一定变化范围,为研究这一变化对整机综合COP的影响,将整机的性能试验分两个阶段进行,其中太阳能热水系统加热段在户外进行,空气源热泵加热段在环境温度可控的环境试验室进行。试验表明在标准规定的变化范围内,平均环境温度的变化及全天辐照量的变化对空气源热泵辅助太阳能热水系统整机综合COP有较大影响,其中因平均环境温度的变化及全天辐照量的变化对太阳能热水系统性能影响而引起整机综合COP

  15. Performance analysis on a solar-powered air-cooled two-staged water ejector cooling system%风冷太阳能双级水喷射制冷空调系统性能分析

    Institute of Scientific and Technical Information of China (English)

    卢苇; 郑立星; 陈洪杰

    2011-01-01

    The performance was analyzed for a solar-powered air-cooled two-staged water ejector cooling system that rated cooling capacity is 12.3 Kw. The cooling capacity of the proposed system increases with the rising of indoor temperature and the enhancement of solar irradiance, while decreases with the rising of the ambient temperature. The COP has similar changing trend with that of the cooling capacity except that it increases rapidly with the enhancement of solar irradiance firstly and then become stable when the solar irradiance exceeding a certain value. The cooling capacity is 7.7~32 Kw and the COP is 0.082~0.107 under the normal operating conditions with indoor temperature over 27℃, ambient temperature below 38 ℃. And solar irradiance surpassing 500 W/m2.%对额定制冷量为12.3kW的风冷太阳能双级水喷射制冷空调系统进行了变工况性能分析.该系统的制冷量随室内温度升高而增大,随环境温度升高而减小,随太阳辐照度增强而增大;COP的变化与制冷量的变化类似,所不同的是COP随着太阳辐照度的增强先迅速增大,当太阳辐照度增大到一定程度后,COP基本保持稳定.在室内温度不低于27℃,室外温度不高于38℃,太阳辐照度不低于500 W/m2的条件下,系统的制冷量为7.7~32 kW,COP为0.082~0.107.

  16. Estimativa da produtividade de arroz irrigado em função da radiação solar global e da temperatura mínima do ar Rice yield estimates based on global solar radiation and minimum air temperature

    Directory of Open Access Journals (Sweden)

    Silvio Steinmetz

    2013-02-01

    Full Text Available Considerando-se a importância da produção do arroz irrigado no Estado do Rio Grande do Sul e que o seu desempenho é influenciado pelas condições meteorológicas, o objetivo deste trabalho foi estimar a produtividade de grãos dessa cultura em função da radiação solar global e da temperatura mínima do ar, usando procedimentos de análise de regressão linear simples e múltipla. Realizou-se um experimento de campo, em Capão do Leão, RS, durante três anos agrícolas. Empregaram-se, em cada ano agrícola, seis datas de semeadura e oito cultivares de diferentes grupos de comprimento de ciclo. Dez colmos principais de cada cultivar foram marcados, para determinarem-se os principais estádios de desenvolvimento. A variável dependente (Y foi a média da produtividade de quatro repetições, de cada época de semeadura, e as variáveis independentes foram: a média da radiação solar global (X¹, a média da temperatura mínima do ar (X² e a média da temperatura mínima do ar elevada ao quadrado (X³, computadas em quatro períodos de desenvolvimento da planta para a radiação solar global e em três períodos para a temperatura mínima do ar. A maioria das variáveis, quando testadas isoladamente, apresentou uma relação linear significativa com a produtividade, mas os coeficientes de determinação (r² foram mais elevados nas regressões lineares múltiplas envolvendo as principais variáveis. Modelos de regressão que utilizam como variáveis preditoras a radiação solar global e a temperatura mínima do ar, em diferentes períodos de desenvolvimento da planta, mostram-se adequados para a estimativa da produtividade de grãos de arroz irrigado.Considering the importance of irrigated rice production in the State of Rio Grande do Sul and that its performance is influenced by the weather conditions, the objective of this study was to estimate the grain yield of this crop as a function of global solar radiation and minimum air

  17. Effect of heat-insulating wall on input energy of a photovoltaic/solar/air-heat system for a residence; Jutaku no kodannetsuka ni yoru taiyoko netsu/taiki netsu system no donyu energy sakugen koka

    Energy Technology Data Exchange (ETDEWEB)

    Kenmoku, Y.; Sakakibara, T. [Toyohashi University of Technology, Aichi (Japan); Nakagawa, S. [Maizuru College of Technology, Kyoto (Japan)

    1996-10-27

    A proposal was made to introduce a photovoltaic/solar/air-heat system which positively utilizes natural energy in order to curtail consumption of fossil energy, corroborating that the system has greatly reduced energy input in the primary energy level in a house. This paper examines the effect of curtailment of energy input in the case of reducing the load of air conditioning through the high heat insulation of a house. The energy input was evaluated by calculating additional equipment energy needed newly for the high heat insulation. The system performance and the energy load varied greatly depending on weather conditions. The subject system consisted of solar cells, inverter, heat concentrator, heat storage tank, heat pump and gas hot-water supply device. The thickening of the insulation sharply reduced heating load in the house, thereby decreasing fuel energy substantially. An insulation material of 100mm thick was capable of reducing energy input by 16-23% compared with that of 50mm thick. 5 refs., 5 figs, 3 tabs.

  18. The Design of Hot Water Supply System of Solar Energy and Air Source Heat Pump%太阳能+空气源热泵的热水供应系统设计

    Institute of Scientific and Technical Information of China (English)

    卢春萍

    2015-01-01

    太阳能集中热水系统受到天气的影响难以全天候运行,需要设置辅助加热装置。以广州市宾馆热水供应为例,对太阳能空气源热泵的热水系统进行设计,包括空气源热泵热水机组选型计算、太阳能集热管面积计算、储热水箱的确定、集热循环水泵的确定。%Influenced by weather condition,it is difficult to run for hot water supply system of solar en-ergy all the time,and the auxiliary heating device need setting.Taking hot water supply in a hotel of Guangzhou city as an example in this paper,the heat pump system of solar energy and air source was designed,including the calculation of equipment selection of the air source heat pump, the calculation of the collector area,the determination of the heat storage tank,and the determina-tion of the circulating pump of the heat collection.

  19. Application of Air Source Heat Pump plus Solar Energy in Domestic Hot Water Preparation System%空气源热泵+太阳能在热水制备系统中的应用

    Institute of Scientific and Technical Information of China (English)

    李超; 卢强; 郭萌; 赵勇

    2015-01-01

    This paper analyzes the commonly used heating modes and gives a detailed introduction of both air source heat pump technology and solar heating technology. Combined with the actual project, the steam heating system of hot water is changed into air source heat pump plus solar heating. By analyzing the actual enetgy consumption data, we obtain the energy -saving value, thus achieve the goal of energy efficiency.%通过对常用供热方式的分析,并对空气源热泵技术、太阳能制热技术原理的介绍,结合工程实际情况,将原蒸汽加热制热水方式改造为空气源热泵+太阳能制热。通过对实际能耗数据的经济分析,得出改造后的节能价值,达到了节约能源的目的。

  20. Solar Electricity

    Science.gov (United States)

    1988-01-01

    ARCO Solar manufactures PV Systems tailored to a broad variety of applications. PV arrays are routinely used at remote communications installations to operate large microwave repeaters, TV and radio repeaters rural telephone, and small telemetry systems that monitor environmental conditions. Also used to power agricultural water pumping systems, to provide electricity for isolated villages and medical clinics, for corrosion protection for pipelines and bridges, to power railroad signals, air/sea navigational aids, and for many types of military systems. ARCO is now moving into large scale generation for utilities.

  1. Solar heating and cooling of buildings

    Energy Technology Data Exchange (ETDEWEB)

    Harrell, J.J. Jr.

    1982-01-01

    The historical background of solar energy usage is presented. Solar energy collection methods and the various types of solar collectors are described. The types of solar water heating systems available and the advantages and disadvantages of each are covered. Solar space heating is addressed and solar air type and liquid type space heating systems are contrasted. Combined solar heating and cooling systems are dealt with. The design of solar systems is discussed. Solar economics covers procedures for determining the most economically feasible solar collector, system financing, and tax incentives. Computer applications describes various computer programs available for use in solar system design. Other topics included are: data processing systems, tips to heed when purchasing a solar system, business opportunities for the professional, and sources of solar information.

  2. Project of air conditioning system by absorption of water-lithium bromide using solar energy and simulation of its operation under several conditions; Projeto de sistema para condicionamento de ar por absorcao de agua-brometo de litio utilizando energia solar e simulacao de sua operacao sob condicoes diversas

    Energy Technology Data Exchange (ETDEWEB)

    Sbravati, Alan; Figueiredo, Jose Ricardo [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Mecanica. Dept. de Energia]. E-mails: alan@fem.unicamp.br; jrfigue@fem.unicamp.br

    2000-07-01

    This article presents computational models for water - lithium bromide absorption air conditioning systems, verifying the use of solar energy as source of heat for the cycle. Four different models were elaborated for the cycle, changing the configurations and hypotheses. In each model two algorithms were elaborated: the first one accomplished the calculations of the heat and mass flows and a estimative of the areas heat transfer, a project of a system, and another which, based on the answers of the first, simulate the behavior of this system when the conditions of initial project are changed, keeping constant the constructive parameters. As in the project a numeric procedure has been used for solution of non lineal systems based on the algorithm of Newton-Raphson. The main alteration among the models went to substitution of the expansion device and evaporator, and, in the fourth model, was increased a procedure for calculation of the solar collector performance. (author)

  3. 太阳能空气源热泵集成热水系统%Hot water system of solar heating combined with air-source heat pump

    Institute of Scientific and Technical Information of China (English)

    陈仕泉; 黄夏东; 谢竹雯; 赵士怀

    2011-01-01

    调查了太阳能热水工程中存在的问题,介绍了太阳能集热器面积的计算方法,提出了保持系统热水量和热水温度稳定的措施以及合理确定贮热水箱和恒温水箱容量的方法.阐述了几种太阳能热水系统的工作原理、适用范围及系统特点.%Investigates the existed problems in solar heating hot water systems. Presents the calculating method of solar collector area, puts forward the measures for keeping stable water quantity and temperature and the methods for rationally determining volume of heat storage tank and thermostatic water tank. Expounds the operation principle, applicability and characteristics of several solar hot water systems.

  4. Solar Indices - Solar Corona

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

  5. Solar Indices - Solar Flares

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

  6. Solar Indices - Solar Ultraviolet

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

  7. Solar Indices - Solar Irradiance

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

  8. A preliminary study of the linear relationship between monthly averaged daily solar radiation and daily thermal amplitude in the north of Buenos Aires provence

    CERN Document Server

    Cionco, R; Rodriguez, R

    2012-01-01

    Using irradiance and temperature measurements obtained at the Facultad Regional San Nicol\\'as of UTN, we performed a preliminary study of the linear relationship between monthly averaged daily solar radiation and daily thermal amplitude. The results show a very satisfactory adjustment (R = 0.848, RMS = 0.066, RMS% = 9.690 %), even taking into account the limited number of months (36). Thus, we have a formula of predictive nature, capable of estimating mean monthly solar radiation for various applications. We expect to have new data sets to expand and improve the statistical significance of these results.

  9. Enhancing performance and uniformity of CH3NH3PbI3-xClx perovskite solar cells by air-heated-oven assisted annealing under various humidities

    Science.gov (United States)

    Zhou, Qing; Jin, Zhiwen; Li, Hui; Wang, Jizheng

    2016-02-01

    To fabricate high-performance metal-halide perovskite solar cells, a thermal annealing process is indispensable in preparing high quality perovskite film. And usually such annealing is performed on hot plate. However hot-plate annealing could cause problems such as inhomogeneous heating (induced by non-tight contact between the sample and the plate), it is also not fit for large scale manufactory. In this paper, we conduct the annealing process in air-heated oven under various humidity environments, and compared the resulted films (CH3NH3PbI3-xClx) and devices (Al/PC61BM/CH3NH3PbI3-xClx/PEDOT:PSS/ITO/glass) with that obtained via hot-plate annealing. It is found that the air-heated-oven annealing is superior to the hot-plate annealing: the annealing time is shorter, the films are more uniform, and the devices exhibit higher power conversion efficiency and better uniformity. The highest efficiencies achieved for the oven and hot-plate annealing processes are 14.9% and 13.5%, and the corresponding standard deviations are 0.5% and 0.8%, respectively. Our work here indicates that air-heated-oven annealing could be a more reliable and more efficient way for both lab research and large-scale production.

  10. Enhancing performance and uniformity of CH3NH3PbI3−xClx perovskite solar cells by air-heated-oven assisted annealing under various humidities

    Science.gov (United States)

    Zhou, Qing; Jin, Zhiwen; Li, Hui; Wang, Jizheng

    2016-01-01

    To fabricate high-performance metal-halide perovskite solar cells, a thermal annealing process is indispensable in preparing high quality perovskite film. And usually such annealing is performed on hot plate. However hot-plate annealing could cause problems such as inhomogeneous heating (induced by non-tight contact between the sample and the plate), it is also not fit for large scale manufactory. In this paper, we conduct the annealing process in air-heated oven under various humidity environments, and compared the resulted films (CH3NH3PbI3−xClx) and devices (Al/PC61BM/CH3NH3PbI3−xClx/PEDOT:PSS/ITO/glass) with that obtained via hot-plate annealing. It is found that the air-heated-oven annealing is superior to the hot-plate annealing: the annealing time is shorter, the films are more uniform, and the devices exhibit higher power conversion efficiency and better uniformity. The highest efficiencies achieved for the oven and hot-plate annealing processes are 14.9% and 13.5%, and the corresponding standard deviations are 0.5% and 0.8%, respectively. Our work here indicates that air-heated-oven annealing could be a more reliable and more efficient way for both lab research and large-scale production. PMID:26879260

  11. 被动式太阳房辅助启动热水热泵式空调系统的设计%Design of Passive Solar House starting Aid Hot Water Heat Pump Air Conditioning System

    Institute of Scientific and Technical Information of China (English)

    李敏; 袁观樑; 邹华生; 陆增杰; 朱悦

    2016-01-01

    In order to solve the problem of cold season heat pump air conditioning is not easy to start , this paper through the effective using solar energy and combined heat pump type air conditioning unit , designed independent household hot water heat pump air -conditioning system , effective utilization of solar energy had been achieved through a simple passive solar channel .So that the function of the whole system was diverse , winter used sun room to preheat air and solve the case after a lower temperature single -stage heat pump difficult to start or poor starting per-formance issues.These could improve the efficiency of the heat pump .In summer, the sun room could dry material or play an effective use of solar energy to provide hot water for the purpose .In the transition season could also use the solar channel to channels to solve the problem of indoors resurgence .Device can achieve a variety of functions , have a variety of operating modes .And match computing device and system equipment was an example for the calculation of Shijiazhuang.Its can provide a reference for single -family homes or small buildings for similar architectural de-sign.%为了解决寒冷季节热泵式空调不易启动的问题,本文通过有效利用太阳能并结合热泵式空调装置,设计了独立户式热水热泵式空调系统,太阳能的有效利用通过一个简易的被动式太阳能通道来实现。从而使整个系统的功能多样化,冬天利用太阳房预热空气,解决气温较低的情况下单级热泵难以启动或启动后性能较差的问题,有效提高热泵的效率。夏天则利用太阳房干燥物料或提供热水起到有效利用太阳能的目的,在过渡季节还可以利用太阳通道的热量解决室内回潮问题。装置可以实现多种功能,可以有多种运行模式。并以石家庄地区为计算实例进行装置及系统设备的匹配计算,能为小栋独立住宅或同类建筑的设计提供参考。

  12. Design and Simulation of Floor Heating System of Solar and Air-energy%太阳能空气能地板供暖系统的设计与仿真

    Institute of Scientific and Technical Information of China (English)

    曾玲; 吴永明; 梁春华

    2015-01-01

    Currently the coal-fired boiler or electric heating, which are main residential heating methods, are of high cost, serious pollution, high energy consumption and low safety. A floor panel heating system which supplied low temperature hot-water by solar collector and air-source heat pump is presented. According to the requirement of the floor panel heating system, the area of solar collector, volume of heat storage tank and power of air-source heat-pump are designed and calculated out. The simulation model of the floor panel heating system is built by Polysun simulation platform to calculate and analyze the energy consumption and economy efficiency. The floor panel heating system with solar collector and air-source heat pump has advantages of energy-saving and good economy, and it is suitable for extension and application.%前家庭供暖主要采用燃煤锅炉或者电加热方式,存在能耗高、成本高、污染严重、安全性能低等问题。针对这种现状,即提出一种采用平板太阳能和空气能热泵联合制取低温热水的地板供暖系统,计算确定了地板供暖系统所需平板太阳能的采光面积、蓄热水箱的体积,以及空气能热泵的功率和型号。运用 Polysun 软件建立了该地板供暖系统仿真模型,并计算分析了供暖系统能量消耗情况和经济性,表明太阳能空气能地板供暖系统是一种环保、节能和具有经济实惠的供暖方式,适宜推广应用。

  13. Ant-nest corrosion of copper tubing in air-conditioning units

    Directory of Open Access Journals (Sweden)

    Bastidas, D. M.

    2006-10-01

    Full Text Available Ant-nest corrosion is a specific type of premature failure (2-3 months of copper tubes used in air-conditioning units causing the loss of refrigerant liquid and the consequent environment pollution. It is known that attack requires the simultaneous presence of moisture, oxygen and a corrodent, usually an organic acid, such as formic, acetic, propionic or butyric acid or other volatile organic substances like methanol, ethanol, formaldehyde or acetoaldehyde. Approximately 10% of all premature failures of copper tubes used in the heating, ventilation and air-conditioning (HVAC industry are the result of ant-nest corrosion. This type of corrosion usually occurs in thin-wall copper pipes, especially when copper is de-sulphurised, and is known by several names: formicary corrosion, unusual corrosion, branched pits, pinhole corrosion, etc.

    Corrosión por “nido de hormigas” es un tipo específico de fallo prematuro (2-3 meses que tiene lugar en tubos de cobre utilizados en sistemas de aire acondicionado originando la pérdida de líquido refrigerante y la consecuente contaminación ambiental. Es conocido que este tipo de ataque requiere la presencia simultánea de humedad, oxígeno y un medio agresivo, habitualmente un ácido orgánico, como fórmico, acético  propiónico o butírico u otras sustancias orgánicas volátiles tales como metanol, etanol, formaldehido o acetoaldehido. Aproximadamente el 10% de los fallos prematuros en tubos de cobre utilizados en calefacción, ventilación y en la industria de aire acondicionado son el resultado de corrosión por nido de hormigas. Frecuentemente, este tipo de corrosión tiene lugar en tubos de cobre de pared delgada, especialmente cuando el cobre es del tipo desulfurizado, y se conoce con varios nombres: corrosión por ácido fórmico, corrosión no habitual, picaduras ramificadas, corrosión con forma de alfiler, etc.

  14. Study of the cosmogenic factors influence on temporal variation of 7Be air concentration during the 23rd solar cycle in Malaga (South Spain)

    International Nuclear Information System (INIS)

    Atmospheric 7Be activity concentrations were measured in Malaga (South Spain) during the period 1997-2007. Monthly concentrations of 7Be ranged between 2.47 and 8.12 mBq m-3 showing seasonal trend with maxima in spring-summer time. Influence of solar activity, cosmic rays and aerosol optical depth on airborne 7Be was analyzed. Weak negative correlation between sunspot number and 7Be is found. Instead, both solar energetic protons >100 MeV and cosmic rays show positive weak significant correlation with this radionuclide. Meteorology may contribute to the low correlation coefficients found. Aerosol optical depth exhibits significant correlation with 7Be, confirming that this radionuclide attaches to atmospheric particles. (author)

  15. 新型平板太阳能PV/T空气集热器传热特性的数值研究%Numerical Simulation of Thermal Performance of a New Type of Flat-Plate Solar PV/T Air Collector

    Institute of Scientific and Technical Information of China (English)

    孙健; 徐银文; 黄章峰; 李杰

    2015-01-01

    文中设计了一款新型PV/T一体化空气集热器,建立了新型PV/T空气系统内部传热过程的一维非稳态数学模型,并利用差分法对模型进行了数值计算。根据计算结果对一体化系统的性能及影响因素进行了分析。结果表明:在一定的光照强度下,随着空气质量流量增加,电池板温度Tp逐渐下降,空气温升逐渐降低;而热效率、光电转化效率、联合效率随空气流量的增加有所升高。模型的建立为高性能太阳能PV/T一体化空气集热器的优化设计提供较好理论依据。%In this paper, a new type of integrated solar PV/T air collector is designed. A one-dimensional unsteady mathematical model is developed, the internal heat transfer process is calculated by ifnite difference approach. The performance of PV/T solar air collector is predicted under different parameters and conditions. Results indicate that the temperature of solar cell and outlet air decrease with the increase of air mass lfow rate under the same incident solar intensity. Then, the thermal efifciency, electrical efifciency and total efifciency of PV/T system increase with the rising of the inlet air mass lfow rate. The models provide valuable theoretical basis for the optimal design of high-performance solar PV/T integrated air system.

  16. Solar building

    OpenAIRE

    Zhang, Luxin

    2014-01-01

    In my thesis I describe the utilization of solar energy and solar energy with building integration. In introduction it is also mentioned how the solar building works, trying to make more people understand and accept the solar building. The thesis introduces different types of solar heat collectors. I compared the difference two operation modes of solar water heating system and created examples of solar water system selection. I also introduced other solar building applications. It is conv...

  17. Solar Imagery - White Light - ISOON

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Improved Solar Observing Optical Network (ISOON) project is a collaboration between the Air Force Research Laboratory Space Vehicles Directorate and the...

  18. 带内插管的太阳能真空管空气集热器热工性能研究%The Thermal Performance Study of Solar Vacuum Tube Air Collector with Intubation

    Institute of Scientific and Technical Information of China (English)

    戚贝贝; 江清阳

    2015-01-01

    This paper presents a vacuum tube air collector with intubation,using the theoryof heat transfer and using mathematical modeling and simulation analysis to analysis the thermal performance of the collector.The simulation results shows that:the air collector can be according to the need to get a temperature of hot air.The higher the speed,the greater the efficiency,but the exit temperature is relatively low.In practice,therefore,according to actual needs to control the air flow speed to obtain heat medium of corresponding temperature.The heat medium can be used in building heating in the winter,and in the summer it can be used as the heat source of air conditioning dehumidification part and dry crops and fruits and so on.It greatly enhances the solar vacuum tube air collector's area and season adaptability.%该研究提出了一种带内插管的真空管空气集热器,利用传热理论,对该集热器的热工性能进行数学建模和模拟分析.模拟结果显示:这种空气集热器可以根据需要获得一定温度的热空气.速度越大,效率就越高,但出口温度相对较低.因此,在实际应用中可根据实际需要控制空气流速获得相应温度的热介质.这些热介质在冬天的时候可用于建筑采暖,在夏天的时候可以作为空调除湿部分的热源及干燥农作物和水果等,大大增强了太阳能真空管空气集热器的地区适应性和季节适应性.

  19. PRESENTATION AND PERFORMANCE ANALYSIS OF A COLLECTOR/REGENERATOR FOR SOLAR LIQUID DESICCANT AIR CONDITIONING SYSTEM%一种太阳能溶液除湿空调集热再生器及其性能分析

    Institute of Scientific and Technical Information of China (English)

    左远志; 杨晓西; 丁静

    2007-01-01

    A new kind of collector/regenerator for solar liquid desiccant air conditioning system is presented, which adopts a fin-forming absorber plate and where the liquid desiccant flow-through process is divided into two stages: preheating stage and regenerating stage.Then the theoretical performance analysis is provided by using the isotherm model and the lumped parameter method. The main results are as follows: (1) the fin-forming absorber plate can increase heat and mass transfer areas and promote turbulence, so that it significantly enhances heat and mass transfer between the air and the liquid desiccant; (2) the two-stage process of liquid regeneration can ensure the mass transfer direction and achieve the approximate constant temperature regeneration process; (3) an increase of the absorber plate fin ratio within a certain range can help to improve the utilization factor of solar energy.%提出并设计了一种采用翅化表面吸热板,溶液流程分为集热加温段与集热再生段的太阳能溶液除湿空调集热再生器,采用等温模型与集总参数法对其做了初步的理论分析.分析结果表明:翅化表面吸热板可通过扩大传热传质面积与增进局部紊流强度来实现传热传质过程强化;溶液流程二段式布置可保证传质方向以及实现近似于等温的再生过程;在一定范围内,增加吸热板的翅化比有利于提高太阳能利用系数.

  20. Research on a New Type of Solar-driven Air-cooled NH3H2O Absorption Refrigeration Cycle%新型太阳能风冷氨水吸收式制冷循环的研究

    Institute of Scientific and Technical Information of China (English)

    任秀宏; 王林

    2012-01-01

    A new type of solar-driven air-cooled NH3H2O absorption refrigeration cycle was proposed. It have rectification e-quipment for purifying ammonia steam and recovers heat from rectifier and absorber. By these realizing small size, air - cooled and the effective use of solar energy. So the coefficient of performance (COP) is increased compared with traditional models. Based on energy conservation, solution mass conservation and ammonia components mass conservation,the thermodynamic math-ematic model of each component is established. Then cycle performance is calculated by writing programs. The effect of main operation parameters(heat source temperature, evaporating temperature,condensing temperature)on the coefficient of performance ( COP) was studied, laying the foundation for optimization design and operation of refrigeration system.%提出一种新型太阳能风冷氨水吸收式制冷循环系统,该系统设置精馏器提纯氨蒸汽,并有效回收精馏器精馏热及中温吸收器吸收热,实现对太阳能的有效利用以及机组风冷化和小型化,与传统系统相比其系统性能系数(COP)显著提高.基于能量守恒、溶液质量守恒和氨组分质量守恒建立系统各部件热力学数学模型,在此基础上编写程序对系统循环特性进行理论计算,分析热源温度、蒸发温度、冷凝温度等参数对系统COP的影响,为系统优化设计及建立最优运行方案提供理论支持.

  1. Air Pollution

    Science.gov (United States)

    Air pollution is a mixture of solid particles and gases in the air. Car emissions, chemicals from factories, dust, pollen and ... Ozone, a gas, is a major part of air pollution in cities. When ozone forms air pollution, ...

  2. CERN... Solar Style

    CERN Multimedia

    2001-01-01

    Inventor William van Sprolant presenting the Solar Club's latest invention, the solar fountain. The CERN Solar Club is giving new meaning to the phrase 'fun in the sun' with their most recently developed contraption, the Solar Fountain. The Fountain was presented to the public just outside of Restaurant 1 on Wednesday October, 17th and uses solar energy to run a water pump at its base to propel a golden plastic ball up into the air. As lovely as the fountain is, the funny thing about it is that the height of the water jet and the ball are an artistic method of measuring the amount of solar power being captured by the photovoltaique panel (no batteries included). The day it was presented started out cloudy, but as the afternoon wore on, the weather brightened and the fountain jumped to life. William van Sprolant, the Solar Fountain's inventor, had great fun with the fountain in front of a group of visiting children swiveling the solar panel in multiple directions. 'Everyone who installs solar panels worrie...

  3. Radiação solar estimada com base na temperatura do ar para três regiões de Minas Gerais Estimation of solar radiation by air temperature models for three regions of Minas Gerais

    Directory of Open Access Journals (Sweden)

    Cláudio R. da Silva

    2012-01-01

    Full Text Available A radiação solar incidente (Rs é uma variável importante em estudos agrícolas, particularmente para a estimativa da evapotranspiração e em modelos para produtividade. Entretanto, sua medição não é, em geral, realizada em estações meteorológicas convencionais. O objetivo deste trabalho foi avaliar nove modelos empíricos de estimativa de Rs, a partir da temperatura, para as regiões Metropolitana, Vale do Rio Doce e Zona da Mata em Minas Gerais. Dados de Rs diários foram obtidos por estações meteorológicas automáticas instaladas nessas regiões e pertencentes ao Instituto Nacional de Meteorologia (INMET. Para todos os modelos foram gerados coeficientes locais de calibração. O desempenho de cada método foi avaliado através dos seguintes indicadores: coeficiente de determinação (R², raiz quadrada do quadrado médio do erro (RQME, erro médio (EM e teste t. A pequena diferença entre os modelos avaliados indica que qualquer um desses modelos é passível de utilização mas, dado à simplicidade, desempenho e significância, o modelo de Hargreaves, calibrado e com dois coeficientes, é o mais aplicável para estimar a radiação solar incidente.The incident solar radiation (Rs is an important variable in agricultural studies, particularly for the estimation of evapotranspiration and yield models. However, its measurement is not commonly performed in conventional meteorological stations. The aim of this study was to evaluate nine empirical models to estimate Rs from the temperature for the Metropolitan, Vale do Rio Doce and Zona da Mata areas in Minas Gerais State, Brazil. The models used were Hargreaves, Annandale, Chen, Bristow & Campbell, Donatelli & Campbell and Hunt. Data used were obtained by Rs daily automatic weather stations installed in these regions and belonging to Instituto Nacional de Meteorologia (INMET. For all models local calibration coefficients were derived. The performance of each method was evaluated

  4. p-i-n/n-i-p type planar hybrid structure of highly efficient perovskite solar cells towards improved air stability: synthetic strategies and the role of p-type hole transport layer (HTL) and n-type electron transport layer (ETL) metal oxides.

    Science.gov (United States)

    Mali, Sawanta S; Hong, Chang Kook

    2016-05-19

    There has been fast recent progress in perovskite solar cells (PSCs) towards low cost photovoltaic technology. Organometal mixed halide (MAPbX or FAPbX) perovskites are the most promising light absorbing material sandwiched between the electron transport layer (ETL) and hole transport layer (HTL). These two layers play a critical role in boosting the power conversion efficiency (PCE) and maintaining air stability. However, the device stability is a serious issue in regular as well as p-i-n inverted type perovskite solar cells. This mini-review briefly outlines the state-of-art of p-i-n/n-i-p type planar hybrid perovskite solar cells using MAPbX/FAPbX perovskite absorbing layers. Later, we will focus on recent trends, progress and further opportunities in exploring the air stable hybrid planar structure PSCs.

  5. p-i-n/n-i-p type planar hybrid structure of highly efficient perovskite solar cells towards improved air stability: synthetic strategies and the role of p-type hole transport layer (HTL) and n-type electron transport layer (ETL) metal oxides

    Science.gov (United States)

    Mali, Sawanta S.; Hong, Chang Kook

    2016-05-01

    There has been fast recent progress in perovskite solar cells (PSCs) towards low cost photovoltaic technology. Organometal mixed halide (MAPbX or FAPbX) perovskites are the most promising light absorbing material sandwiched between the electron transport layer (ETL) and hole transport layer (HTL). These two layers play a critical role in boosting the power conversion efficiency (PCE) and maintaining air stability. However, the device stability is a serious issue in regular as well as p-i-n inverted type perovskite solar cells. This mini-review briefly outlines the state-of-art of p-i-n/n-i-p type planar hybrid perovskite solar cells using MAPbX/FAPbX perovskite absorbing layers. Later, we will focus on recent trends, progress and further opportunities in exploring the air stable hybrid planar structure PSCs.

  6. Integrated Solar Photovoltaic and Ground Source Heat Pump Air-condition System of the Plant Factory%太阳能光伏-地源热泵式供能植物工厂空调系统

    Institute of Scientific and Technical Information of China (English)

    陈慧子; 石惠娴; 裴晓梅; 游煜成; 朱洪光

    2013-01-01

    针对目前植物工厂主要采用的化石燃料供能方式释放出大量温室气体和有害气体危害环境的问题,设计太阳能光伏-地源热泵式供能植物工厂空调系统,利用地下水源热泵制冷供暖植物工厂,借助太阳能光伏技术供电地源热泵系统。植物工厂位于同济大学生态园内,属自然光利用联栋小屋脊玻璃温室,占地面积927 m2。通过确定植物工厂的冷热负荷选型制热量和制冷量分别为264 kW和240 kW的水源热泵,地下水抽水量为32.46 m3/h,确定太阳能光伏阵列总功率为54667 wp。最后分析了太阳能光伏-地源热泵式供能植物工厂空调系统的经济效益和节能减排效益。%To solve the problem of a large number of greenhouse gas and harmful gas polluting environment, which released by fossil fu-els used to supply energy to plant factory, integrated solar photovoltaic and ground source heat pump air-condition system is designed, more specifically, using groundwater source heat pump to heat and cool plant factory and utilizing photovoltaic technology to power the groundwater source heat pump. The plant factory of 927m2, located in ecological garden of Tongji University, is small-roof multi-span glass greenhouse with natural light. Choosing the water source heat pump of heating capacity and refrigeration capacity are 264 kw and 240 kw respectively through the cooling and heating load of the plant factory, the quantity of pumping groundwater is 32.46 m3/h, the total power of solar photo-voltaic array is 54 667 wp. The economic benefits and energy conservation and emissions reduction benefits of the integrated solar photovolta-ic and ground source heat pump air-condition system of the plant factory are analysed finally.

  7. Defect chemical explanation for the effect of air anneal on CdS/CuInSe/sub 2/ solar cell performance

    Energy Technology Data Exchange (ETDEWEB)

    Cahen, D.; Noufi, R.

    1989-02-06

    We formulate a consistent defect chemical model of the effect of air/O/sub 2/ anneals on CdS/CuInSe/sub 2/ devices. The model centers on O-induced neutralization of (near) surface donor states in CuInSe/sub 2/ grains. The simplest identification of these states is with ionized Se vacancies, due to coordinatively unsaturated In on grain surfaces and boundaries.

  8. Thermoeconomic Analysis and Optimisation of Air-Based Bottoming Cycles for Water-Free Hybrid Solar Gas-Turbine Power Plants

    OpenAIRE

    Sandoz, Raphael

    2012-01-01

    The growing worldwide energy demand and the impacts of climate change due to anthropogenic greenhouse gases emissions are among the major issues facing humanity. The global energy system, responsible for most of the greenhouse gases emissions, is therefore at the heart of global concerns. In particular, the search for a reliable, sustainable and environmentally friendly means of generating electricity is a crucial matter, with growing worries about the scarcity of fossil resources, air pollut...

  9. Experimental investigation of an innovative thermochemical process operating with a hydrate salt and moist air for thermal storage of solar energy: Global performance

    International Nuclear Information System (INIS)

    Highlights: • A large scale thermochemical storage system working with moist air is experimented. • High energy density (203 kW h/m3) and storage capacity (105 kW h) have been obtained. • Hydration specific powers between 0.75 and 2 W/kg have been reached. • The ways to control the storage system have been deeply investigated. • Two important parameters (equilibrium drop and mass flowrate) have been identified. - Abstract: This paper investigates an innovative open thermochemical system dedicated to high density and long term (seasonal) storage purposes. It involves a hydrate/water reactive pair and operates with moist air. This work focuses on the design of and experimentation with a large scale prototype using SrBr2/H2O as a reactive pair (400 kg of hydrated salt, 105 kW h of storage capacity and a reactor energy density of 203 kW h/m3). Promising conclusions have been obtained regarding the feasibility and performance of such a storage process. Hydration specific powers from 0.75 to 2 W/kg have been reached for a bed salt energy density of 388 kW h/m3. Moreover, two important parameters that control the storage system have been identified and investigated: the equilibrium drop and the mass flow rate of moist air. Both have a strong influence on the reaction kinetics and therefore on the reactor’s thermal power

  10. Study on Thermal Responsive Performance of a Test Room Equipped with Solar Air Heating System%太阳能空气供暖系统作用下建筑物热响应特性的研究

    Institute of Scientific and Technical Information of China (English)

    姚微; 陈滨; 张志成; 杨文晓

    2011-01-01

    Most of previous researches on solar air heating system (SAHS) were separated from real building. Actually, even though the building was equipped with a high-effective SAHS, the effective regulation could not be obtained without considering the building thermal responsive characteristics. In this paper,a test room equipped with wall-mounted solar air collector on south wall was taken as a research object,and in real coldest outdoor environment conditions (almost below -5 ℃ during night) ,dynamic variation process of indoor temperature under different conditions were experimentally studied based on the computer datalog system and outdoor weather station which could record data automatically. The experimental conditions included the different air supply modes, movable thermal insulation of window, direct-gain window's action and the factor of thermal mass materials. The results could provide the useful references for further studying the climate adaptation of this technology and predicting dynamic indoor temperature swings of building.%既有关于太阳能空气供暖系统(SAHS)的研究大多是脱离建筑物而进行的.然而,实际情况是,即便是配置一个高效的太阳能空气供暖系统,如果不考虑建筑物的热响应特性,往往也不能获得好的室内环境调节效果.本文以在南向墙设置有壁挂式太阳能空气集热器的实验房为研究对象,在实际最寒冷的室外气候条件下(夜间大多低于-5℃),利用计算机多点巡同检测系统和可自动记录数据的室外气象站,通过实测数据和理论分析研究了不同送风方式、窗户的移动式保温、直接受益窗单独作用及热质材料等因素作用下室内温度的动态变化过程,为今后进一步研究该项技术的地域适应性及预测建筑集成太阳能空气供暖系统作用下的动态室温波动提供了参考依据.

  11. Acknowledgement Of Evacuated Tube Solar Water Heater Over Flat Plate Solar Water Heater

    OpenAIRE

    Dharamvir Mangal; Devander Kumar Lamba; Tarun Gupta; Kiran Jhamb

    2010-01-01

    This paper presents acknowledgement to one of the latest solar water heater which is evacuated solar water heater based on a Thermo siphon principle used for heating water for domestic purposes in household by utilizing solar radiations. As the air is evacuated from the solar tube to form a vacuum, this greatly reduces conductive and convective heat loss from the interior of tube. As a result wind and cold temperature have less effect on the efficiency of evacuated solar water heater. Result ...

  12. Simple, economical solar collector

    Science.gov (United States)

    Anthony, K.

    1979-01-01

    Hot air solar collector designed for economy and simplicity is assembled from only three parts: (1) molded urethane foam body, (2) flat sheet metal collector panel and (3) transparent cover. Large arrays may be assembled by inserting male fittings of each collector into female fitting of adjacent collector.

  13. Recovering from "amnesia" brought about by radiation. Verification of the "Over the air" (OTA) application software update mechanism On-Board Solar Orbiter's Energetic Particle Detector

    Science.gov (United States)

    Da Silva, Antonio; Sánchez Prieto, Sebastián; Rodriguez Polo, Oscar; Parra Espada, Pablo

    Computer memories are not supposed to forget, but they do. Because of the proximity of the Sun, from the Solar Orbiter boot software perspective, it is mandatory to look out for permanent memory errors resulting from (SEL) latch-up failures in application binaries stored in EEPROM and its SDRAM deployment areas. In this situation, the last line in defense established by FDIR mechanisms is the capability of the boot software to provide an accurate report of the memories’ damages and to perform an application software update, that avoid the harmed locations by flashing EEPROM with a new binary. This paper describes the OTA EEPROM firmware update procedure verification of the boot software that will run in the Instrument Control Unit (ICU) of the Energetic Particle Detector (EPD) on-board Solar Orbiter. Since the maximum number of rewrites on real EEPROM is limited and permanent memory faults cannot be friendly emulated in real hardware, the verification has been accomplished by the use of a LEON2 Virtual Platform (Leon2ViP) with fault injection capabilities and real SpaceWire interfaces developed by the Space Research Group (SRG) of the University of Alcalá. This way it is possible to run the exact same target binary software as if was run on the real ICU platform. Furthermore, the use of this virtual hardware-in-the-loop (VHIL) approach makes it possible to communicate with Electrical Ground Support Equipment (EGSE) through real SpaceWire interfaces in an agile, controlled and deterministic environment.

  14. Solar ventilation and tempering

    Science.gov (United States)

    Adámek, Karel; Pavlů, Miloš; Bandouch, Milan

    2014-08-01

    The paper presents basic information about solar panels, designed, realized and used for solar ventilation of rooms. Used method of numerical flow simulation gives good overview about warming and flowing of the air in several kinds of realized panels (window, facade, chimney). Yearlong measurements give a good base for calculations of economic return of invested capital. The operation of the system in transient period (spring, autumn) prolongs the period without classical heating of the room or building, in winter the classical heating is supported. In the summer period the system, furnished with chimney, can exhaust inner warm air together with necessary cooling of the system by gravity circulation, only. System needs not any invoiced energy source; it is supplied entirely by solar energy. Large building systems are supported by classical electric fan respectively.

  15. Enhancement of Integrated Solar Collector with Spherical Capsules PCM Affected by Additive Aluminum Powder

    OpenAIRE

    Fatah O. Al Ghuol; Sopian, K.; Shahrir Abdullah

    2016-01-01

    This research aims to study, analyze, design, and construct a solar air heater combined with an appropriate phase-change material (PCM) unit. This solar air heater is analogous to a collector integrating a thermal storage unit and a solar thermal collector. In this study, such single-pass solar air heater in amalgamation with PCM was constructed, and several tests were conducted on this device. During the experiments for the solar collector with PCM (spherical capsules), the temperature varie...

  16. 太阳能叉流液体除湿空调再生热质传递稳态实验%Heat and mass transfer experiments of regenerator in solar-driven cross-flow liquid desiccant air conditioning

    Institute of Scientific and Technical Information of China (English)

    高文忠; 柳建华; 章学来

    2011-01-01

    Regenerator is one of the core components in a liquid desiccant air-conditioning system driven by solar energy, and its efficiency directly affects the performance of the system. The feasibility to obtain outlet parameters for the regeneration from its efficiency and import parameters was analyzed, and a cross-flow regenerator was established, in which LiCl solution and Celdek structured packing were used. Enthalpy efficiency and moisture efficiency were adopted to describe the heat and mass transfer performance of the regenerator. Influences of desiccant and air inlet parameters on the regenerator performance were experimentally investigated. The results show that the enthalpy efficiency is mainly affected by the flow rate and temperature of the solution, and the flow rate, temperature and moisture content of air. The moisture efficiency depends on the flow rate, temperature and concentration of the solution as well as the flow rate of air, but has little relationship with other variables. The error between the linear regression equation and experimental data is less than 20% . Thus the outlet state can be predicted from inlet parameters.%再生器是太阳能液体除湿系统的核心设备,其效率直接影响整个系统的性能.分析了再生器出口参数由进口参数和效率直接获得的可行性,并建立叉流液体再生系统,采用氯化锂为再生溶液,Celdek填料为热质交换介质,实验测试溶液和空气进出口参数对再生器全热效率和湿度效率的影响规律,并进行线性回归,结果表明:全热效率主要受溶液流量、温度以及空气流量、温度和含湿量的影响;湿度效率和溶液流量、温度、浓度以及空气流量关联性强,与其他变量关系很小;线性回归方程计算结果和实验结果误差基本在20%以内,可通过进口参数预测出口状态.

  17. Job creation potential of solar

    International Nuclear Information System (INIS)

    This document defines the size of the job market within Canada's solar industry and presents a preliminary forecast of the employment opportunities through to 2025. The issue of job potential within Canada's solar technologies is complicated by the wide range of different fields and technologies within the solar industry. The largest energy generator of the solar technologies is passive solar, but the jobs in this sector are generally in the construction trades and window manufacturers. The Canadian Solar Industries Association estimates that there are about 360 to 500 firms in Canada with the primary business of solar technologies, employing between 900 to 1,200 employees. However, most solar manufacturing jobs in Canada are for products exports as demonstrated by the 5 main solar manufacturers in Canada who estimate that 50 to 95 per cent of their products are exported. The main reason for their high export ratio is the lack of a Canadian market for their products. The 3 categories of job classifications within the solar industry include manufacturing, installation, and operations and maintenance. The indirect jobs include photovoltaic system hardware, solar hot water heating, solar air ventilation, and glass/metal framing. 17 refs., 3 tabs., 2 figs

  18. Solar Features - Solar Flares

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A solar flare is a short-lived sudden increase in the intensity of radiation emitted in the neighborhood of sunspots. For many years it was best monitored in the...

  19. Air Abrasion

    Science.gov (United States)

    ... delivered directly to your desktop! more... What Is Air Abrasion? Article Chapters What Is Air Abrasion? What Happens? The Pros and Cons Will I Feel Anything? Is Air Abrasion for Everyone? print full article print this ...

  20. Solar storms; Tormentas solares

    Energy Technology Data Exchange (ETDEWEB)

    Collaboration: Pereira Cuesta, S.; Pereira Pagan, B.

    2016-08-01

    Solar storms begin with an explosion, or solar flare, on the surface of the sun. The X-rays and extreme ultraviolet radiation from the flare reach the Earths orbit minutes later-travelling at light speed. The ionization of upper layers of our atmosphere could cause radio blackouts and satellite navigation errors (GPS). Soon after, a wave of energetic particles, electrons and protons accelerated by the explosion crosses the orbit of the Earth, and can cause real and significant damage. (Author)

  1. Central solar energy receiver

    Science.gov (United States)

    Drost, M. Kevin

    1983-01-01

    An improved tower-mounted central solar energy receiver for heating air drawn through the receiver by an induced draft fan. A number of vertically oriented, energy absorbing, fin-shaped slats are radially arranged in a number of concentric cylindrical arrays on top of the tower coaxially surrounding a pipe having air holes through which the fan draws air which is heated by the slats which receive the solar radiation from a heliostat field. A number of vertically oriented and wedge-shaped columns are radially arranged in a number of concentric cylindrical clusters surrounding the slat arrays. The columns have two mirror-reflecting sides to reflect radiation into the slat arrays and one energy absorbing side to reduce reradiation and reflection from the slat arrays.

  2. Design and research on solar steamy hot-air drying system%太阳能蒸汽热风干燥系统的设计与研究

    Institute of Scientific and Technical Information of China (English)

    裴坤; 段凤江; 孔晓玲; 于鹏

    2012-01-01

    研制一套太阳能干燥系统,采用真空集热管对水加热,产生水蒸气,并转换成热风,实现对农产品的干燥作业.以胡萝卜作为样品进行干燥机的干燥性能试验,结果表明:当太阳辐射值达到750 W/m2以上时,蒸汽可以稳定工作5~7 h;干燥室内高温工作段温度可以稳定在55℃左右,低温工作段温度可以稳定在40℃左右.干燥后的胡萝卜脱水率为82.3%~86.5%,干燥效果良好.%Designed and developed a set of solar drying systems, use the vacuum tube collector to heal water, the system can produce steam, and then converted it into hot air, realize the drying of agricultural products. The experiments of drying carrots were carried out to test the drying system's performance. The results show that when solar power reaches above 750 W/m2, the steam can stable work for 5~7 hours;The temperature of the dryer's high temperature section can be stabilized at around 55?,artd the temperature of the low can be stabilized at around 40?. The dehydration rate of dried carrots is between 82. 3% -~ 86. 5% ,drying effect is good.

  3. Components of solar thermal systems

    OpenAIRE

    Mendes, J. Farinha; Carvalho, M. J.; Schossig, Peter

    2013-01-01

    The heat production sub-system is the part of the overall system which provides heat to a thermally driven air-conditioning system. With regards to the solar-driven equipment, the solar collector is the main component of the sub-system. A brief review on the present state-of-the-art with respect to performance characteristics and available certification schemes of solar collectors is given in the following chapter. Besides the solar collector field, the storage unit and the back-up heat sourc...

  4. The Solar Dynamo Zoo

    Science.gov (United States)

    Egeland, Ricky; Soon, Willie H.; Baliunas, Sallie L.; Hall, Jeffrey C.; Pevtsov, Alexei A.; Henry, Gregory W.

    2016-05-01

    We present composite time series of Ca II H & K line core emission indices of up to 50 years in length for a set of 27 solar-analog stars (spectral types G0-G5; within ~10% of the solar mass) and the Sun. These unique data are available thanks to the long-term dedicated efforts of the Mount Wilson Observatory HK project, the Lowell Observatory Solar-Stellar Spectrograph, and the National Solar Observatory/Air Force Research Laboratory/Sacremento Peak K-line monitoring program. The Ca II H & K emission originates in the lower chromosphere and is strongly correlated with the presence of magnetic plage regions in the Sun. These synoptic observations allow us to trace the patterns long-term magnetic variability and explore dynamo behavior over a wide range of rotation regimes and stellar evolution timescales.

  5. Hot Air Engines

    Directory of Open Access Journals (Sweden)

    P. Stouffs

    2011-01-01

    Full Text Available Invented in 1816, the hot-air engines have known significant commercial success in the nineteenth century, before falling into disuse. Nowadays they enjoy a renewed interest for some specific applications. The "hot-air engines" family is made up of two groups: Stirling engines and Ericsson engines. The operating principle of Stirling and Ericsson engines, their troubled history, their advantages and their niche applications are briefly presented, especially in the field of micro-combined heat and power, solar energy conversion and biomass energy conversion. The design of an open cycle Ericsson engine for solar application is proposed. A first prototype of the hot part of the engine has been built and tested. Experimental results are presented.

  6. Mineralization of phthalic acid by solar photoelectro-Fenton with a stirred boron-doped diamond/air-diffusion tank reactor: Influence of Fe3+ and Cu2+ catalysts and identification of oxidation products

    International Nuclear Information System (INIS)

    Highlights: • Almost total mineralization of phthalic acid by solar photoelectro-Fenton with Fe3+, Cu2+ and Fe3+–Cu2+ mixtures. • Hydroxyl radical generation from photo-Fenton reaction under solar radiation. • Enhancement of the mineralization rate using Fe3+ and small amounts of Cu2+. • Detection of eleven aromatic intermediates and six short-linear carboxylic acids. • Oxidation of Cu(II)-carboxylate complexes with ·OH and photolysis of Fe(III)-carboxylate species. -- Abstract: Here, the substrate decay and mineralization rate for 100 cm3 of a 2.0 mM phthalic acid solution in 0.10 M Na2SO4 of pH 3.0 have been studied by electro-Fenton (EF) and solar photoelectro-Fenton (SPEF). The electrochemical cell was a stirred tank reactor containing a 3 cm2 boron-doped diamond (BDD) anode and a 3 cm2 air-diffusion cathode that generates H2O2. Cu2+ and/or Fe3+ were added as catalysts with total concentration of 0.50 mM and a constant current density of 33.3 mA cm−2 was applied. In EF with Cu2+ or Fe3+ alone and SPEF with only Cu2+, phthalic acid decayed slowly and poor mineralization was reached because the main oxidant was ·OH produced at the BDD surface from water oxidation. In contrast, the substrate destruction was largely enhanced using SPEF with 0.50 mM Fe3+ since a high quantity of oxidant ·OH was produced in the bulk induced by photo-Fenton reaction. This treatment led to an almost total mineralization by the photolysis of generated Fe(III)-carboxylate complexes. In all cases, the decay of phthalic acid obeyed a pseudo-first-order reaction. The combination of Cu2+ and Fe3+ as catalysts accelerated the mineralization process in SPEF because Cu(II)-carboxylate complexes were also removed with ·OH formed from photo-Fenton reaction. The best SPEF process was found for 0.125 mM Cu2+ + 0.375 mM Fe3+, giving rise to 99% mineralization with 40% current efficiency and 0.294 kWh g−1 TOC energy consumption. Eleven aromatics and six short-linear carboxylic

  7. Ventilation and hot water supply solar-heat collector

    OpenAIRE

    Овсянникова, Ирина Михайловна; Немировский, Илья Абрамович; Ганжа, Антон Николаевич

    2014-01-01

    Solar collectors intended for hot water supply needs are widely used today. However, the territorial position of Ukraine prevents their efficient use during the cold period of the year. This reduces their utilization factor and increases the payback period. The use of solar collectors as the recuperators of exhaust air will allow for their efficient operation during the heating season. This becomes possible because the cold air is heated by the indoor waste air heat particularly in the solar ...

  8. Porous materials for solar thermal and spin-off applications

    OpenAIRE

    Fend, Thomas; Brendelberger, Stefan; Rietbrock, Peter; Smirnova, Olena

    2009-01-01

    This presentation gives an overview on latest research activities in the field of hot gas flow through highly porous materials. The overall objective is to describe the thermal behaviour of these kinds of materials when applied as solar air receivers for solar tower technology. In this application, concentrated solar radiation heats up the material, which continuously transfers the energy to an air circuit. After that, the hot air feeds a steam turbine process. Since equivalent physical proc...

  9. Experimental investigation of the effect of variously-shaped ribs on local heat transfer on the outer wall of the turning portion of a U-channel inside solar air heater

    Science.gov (United States)

    Salameh, Tareq; Alami, Abdul Hai; Sunden, Bengt

    2016-03-01

    In the present work, an experimental investigation of convective heat transfer and pressure drop was carried out for the turning portion of a U-channel where the outer wall was equipped with ribs. The shape of the ribs was varied. The investigation aims to give guidelines for improving the thermo-hydraulic performance of a solar air heater at the turning portion of a U-channel. Both the U-channel and the ribs were made in acrylic material to allow optical access for measuring the surface temperature by using a high-resolution technique based on narrow band thermochromic liquid crystals (TLC R35C5 W) and a CCD camera placed to face the turning portion of the U-channel. The uncertainties were estimated to 5 and 7 % for the Nusselt number and friction factor, respectively. The pressure drop was approximately the same for all the considered shapes of the ribs while the dimpled rib case gave the highest heat transfer coefficient while the grooved rib presented the highest performance index.

  10. The solar energy hot water system paired with auxiliary heat system of air source heat pump%以空气源热泵辅助加热的太阳能热水系统

    Institute of Scientific and Technical Information of China (English)

    施龙; 刘刚; 杨丰畅

    2013-01-01

    介绍了太阳能热泵热水系统的运行原理及控制方式,分析了太阳能热泵热水系统在上海某高校 学生宿舍的应用情况.以每吨热水的加热成本为指标,对几种热源热水系统的经济性进行了比较,分析了太阳能热泵热水系统的节能效果.%An operating principles and control strategies of solar energy hot water system with air source heat pump for auxiliary heating were introduced. Then an application in the students' dormitories of one university in Shanghai was analyzed. Basing on an index which was the cost of heating 1 ton water, the economic efficiency of several heat sources was compared, and higher energy-saving effect of current system was concluded.

  11. 小型太阳能吸收式空调的运行特性和室内热舒适性试验%Operation Characteristics of Minitype Solar Absorption Air-Conditioning and Indoor Thermal Comfort Test

    Institute of Scientific and Technical Information of China (English)

    李悦; 翟晓强; 王如竹; 尹亚领; 宋兆培

    2011-01-01

    Experiments were carried out to study a minitype solar absorption air-conditioning system in the summer typical condition. The system consists of 96 m^2 vacuum tube collectors, one adsorption chiller with nominal refrigeration capacity of 8 kW, hot water%在夏季典型工况下,对一个小型太阳能吸收式空调系统进行了试验研究。试验系统主要包括:96m^2的真空管集热器、额定制冷量为8kW的吸收式制冷机、容量为3t的热水储水箱、500L蓄冷水箱以及50m^2冷辐射吊顶。试验结果显示吸收式制冷机的制冷量平均为3.9kW,每天达到的平均制冷时间为10h。分析了室内的热舒适情况,得出了PMV值为-0.2%,PPD值为5%,室内热环境达到舒适水平。

  12. Synthetic fiber air collectors for agricultural uses

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, H.

    Details are given on an innovative air collector system made of porous black synthetic fibers to take in air and absorb solar radiation to heat it. Synthetic fiber collectors are unexpensive, they are characterized by their efficient heat transfers, good working properties, and wind resistance. Excessive heating, condensates, and dusts are avoided using them. Schematic sketches facilitate access to the fibrous structure, uses, design and construction of solar air collectors made of Nicolon fibers. Temperature and collector capacity measuring results are shown in a diagram. Details are given on a small-scale solar drier drying herbs (solar collector system with a 36 m/sup 2/ fibrous absorber surface) as well as on experiences gained in the operation of more than 20 solar driers of the kind described. (HWJ).

  13. Solar Combisystems

    DEFF Research Database (Denmark)

    Thür, Alexander

    2006-01-01

    This note first introduces what is a solar combisystem, the structure how a solar combisystem is build up and what are criteria’s to evaluate a solar combisystem concept. Further on the main components of a solar combisystem, the main characteristics and possible advantages and disadvantages...... compared to each other are described. It is not the goal of this note to explain the technical details how to design all components of a solar combisystem. This is done during other lectures of the solar course and in other basic courses as well. This note tries to explain how a solar combisystem...

  14. Solar energy

    Science.gov (United States)

    Rapp, D.

    1981-01-01

    The book opens with a review of the patterns of energy use and resources in the United States, and an exploration of the potential of solar energy to supply some of this energy in the future. This is followed by background material on solar geometry, solar intensities, flat plate collectors, and economics. Detailed attention is then given to a variety of solar units and systems, including domestic hot water systems, space heating systems, solar-assisted heat pumps, intermediate temperature collectors, space heating/cooling systems, concentrating collectors for high temperatures, storage systems, and solar total energy systems. Finally, rights to solar access are discussed.

  15. EDITORIAL Solar harvest Solar harvest

    Science.gov (United States)

    Demming, Anna

    2010-12-01

    into the charge transport mechanism and trap distribution in these composites [3]. An advantage of investigating solar cell technology based on organic materials rather than silicon is that silicon photovoltaics requires high-purity silicon, whereas the material demands of organic technology are not nearly so strict. Work by researchers in Denmark and Germany highlights the simplicity and tolerance to ambient conditions of organic photovoltaic fabrication in the demonstration of a nanostructured polymer solar cell made from a thermocleavable polymer material and zinc oxide nanoparticles. All the manipulations during device preparation could be carried out in air at around 20 °C and 35% humidity [4]. A possible route to enhancing cell performance is through the improvment of the transport efficiency. Researchers in Taiwan demonstrate how effectively this can be implemented in a hybrid device comprising TiO2 nanorods and poly[2-methoxy-5-(2-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV) [5]. In addition, inorganic semiconductor nanocrystals that have tunable optical bandgaps can be combined with organic semiconductors for the fabrication of hybrid photovoltaic devices with broad spectral sensitivity. A collaboration of researchers in the UK and the US has now developed a near-infrared sensitive hybrid photovoltaic system with PbS nanocrystals and C60. The reported improvement in device performance is attributed to increased carrier mobility of the PbS nanocrystal film [6]. In this issue, Patrick G Nicholson and Fernando A Castro from the National Physical Laboratory in the UK present a topical review on the principles and techniques for the characterization of organic photovoltaics [7]. The review presents a comprehensive picture of the current state-of-the-art understanding of the working mechanisms behind organic solar cells, and also describes electronic morphological considerations relevant to optimizing the devices, as well as different nanoscale techniques for

  16. Research of solid-solid phase change heat storage material applied in solar collector to produce high temperature air%固-固相变蓄热材料在太阳能高温空气集热系统中的应用研究

    Institute of Scientific and Technical Information of China (English)

    胡仁林; 刘振华; 赵峰; 肖红升

    2012-01-01

    为利用太阳能获得稳定持续的高温空气工质,除了有效集热外,还需要解决因太阳辐射强度变化导致输出工质温度波动的问题.在性能优良的太阳能集热系统中采用蓄热技术是解决此问题的有效途径.根据给定的设计目标,研究将固-固相变蓄热材料季戊四醇应用到太阳能集热蓄热一体化的实验装置中.实验结果表明:按集热蓄热一体化思路设计的实验装置,集热单元能够输出最高温度超过220℃的高温空气,蓄热单元能够将高温空气的温度稳定在蓄热材料的相变温度附近.并且随着蓄热管级数的增加,空气出口温度稳定的时间就越长,为利用太阳能获得稳定持续的高温热媒工质奠定了基础.%In order to get high temperature air constantly through the utilization of solar energy,the fluctuation of the air outlet temperature caused by the changing solar radiation must also be taken into consideration besides the effective collection of solar energy. Therefore,the adoption of heat storage technology in a solar energy collector of high efficiency is a feasible approach to diminish the temperature fluctuation. The solid-solid phase change material-Pentaerythritol was used as heat storage material in the solar energy collector/storage designed by an integrated method. The experimental results indicate that the maximum air outlet temperature of heating units exceeds 220 ℃ and the heat storage units can stabilize the air temperature around the phase-transition temperature of Pentaerythritol for a short time,which tends to be longer with the increase of the number of heat storage units. The results provide a foundation for the utilization of solar energy collector to get stable and high temperature air constantly through the application of phase change material.

  17. Solar thanksgiving; Solarer Erntedank

    Energy Technology Data Exchange (ETDEWEB)

    Zehner, Mike; Doll, Andreas [Hochschule Muenchen (Germany). Arbeitsgruppe PV-Systeme; Hammer, Annette [Oldenburg Univ. (Germany). Arbeitsgruppe Energiemeteorologie; Heesen, Henrik te [Meteocontrol GmbH, Augsburg (Germany). Forschungsprojekt zur Analyse von Fernueberwachungsmessdaten; Herbort, Volker [Meteocontrol GmbH, Augsburg (Germany). Bereich Data-Mining-Vorhaben; Mariani, Marco [Meteocontrol GmbH, Augsburg (Germany). Abt. PV Ertragsgutachten und Prognosen

    2012-03-09

    While the 'felt' weather in 2011 was quite rainy, it was in fact one of the five hottest years since 1881, with many sunshine hours. This is reflected in photovoltaic power generation in 2011. Many owners of PV systems were surprised to find record solar power generation figures. In many cases, even the best case scenarios were topped.

  18. Solar Collectors

    Science.gov (United States)

    1980-01-01

    Solar Energy's solar panels are collectors for a solar energy system which provides heating for a drive-in bank in Akron, OH. Collectors were designed and manufactured by Solar Energy Products, a firm established by three former NASA employees. Company President, Frank Rom, an example of a personnel-type technology transfer, was a Research Director at Lewis Research Center, which conducts extensive solar heating and cooling research, including development and testing of high-efficiency flat-plate collectors. Rom acquired solar energy expertise which helped the company develop two types of collectors, one for use in domestic/commercial heating systems and the other for drying grain.

  19. Solar-powered pump

    Science.gov (United States)

    Kirsten, C. C. (Inventor)

    1976-01-01

    A solar powered pump particularly suited for intermittently delivering a stream of water is reported. The pump is characterized by a housing adapted to be seated in a source of water having a water discharge port disposed above the water line of the source, a sump including a valved inlet port through which water is introduced to the sump, disposed beneath the water line, a displacer supported for vertical reciprocation in said housing, an air passageway extended between the vertically spaced faces of the displacer, and a tipple disposed adjacent to the water discharge port adapted to be filled in response to a discharge of water from the housing. Air above a displacer is expanded in response to solar energy impinging on the housing and transferred into pressurizing relation with the sump for forcing water from the sump.

  20. DESIGN AND PERFORMANCE OF A SOLAR ABSORPTION AIR-CONDITIONING AND HEAT-SUPPLY SYSTEM%太阳能吸收式空调及供热系统的设计和性能

    Institute of Scientific and Technical Information of China (English)

    何梓年; 朱宁; 刘芳; 郭淑玲

    2001-01-01

    A solar absorption air-conditioning and heat-suppl ycomprehensive system has been constructed in Rushan,Shandong Province.The system consists of heat-pipe evacuated tubular collectors,lithium-bromide absorption c hiller,hot water storage tanks,chilled water storage tank,domestic water storage tank,circulating pumps,cooling tower,fan-coil units,auxiliary oil-burned boil er and control system.The system has a multifunction of space cooling in summer,sp ace heating in winter and domestic water heating in other seasons,with a total c ollector aperture area of 540m2,cooling and heating capacity of 100kW,air-con d itioning construction area of 1000m2 and domestic hot water supply of 32m3 p er day.Design characteristics and measuring performance of the system were prese nted.%一套太阳能吸收式空调及供热综合系统已在山东省乳山市建成。该系统由热管式真空管集热器、溴化锂吸收式制冷机、储水箱、循环泵、冷却塔、空调箱、辅助燃油锅炉和自动控制系统等几部分组成,具有夏季制冷、冬季供热和全年提供生活用热水等功能。太阳能集热器总采光面积540m2,制冷、供热功率100kW,空调、采暖建筑面积1000m2,供生活用热水量32m3/d。文中着重介绍了系统的设计特点和测试性能。

  1. 近50年来中国东、西部地面太阳辐射变化及其与大气环境变化的关系∗%Correlative analysis b etween the changes of surface solar radiation and its relationship with air p ollution, as well as meteorological factor in East and West China in recent 50 years

    Institute of Scientific and Technical Information of China (English)

    齐月; 房世波; 周文佐

    2015-01-01

    Based on the solar radiation information and climatic observation data from 1961 to 2011 in both East and West China, the interannual trends of surface solar radiation are investigated. By combining with cloud cover, sunshine percentage, sunshine duration, wind speed, atmospheric turbidity, and relative humidity, the causes affecting the varia-tions of the total surface solar radiation in East and West China are analyzed. The results show that the surface solar radiation decreased from 1961 to 2010 in both East and West China, but there was an abrupt change, which occurred in the early 1990s, followed by sustained increase. The surface solar radiation decreased from 1961 to 2010 in East China, and the decrease of surface solar radiation in the eastern region was greater than in the western region. The surface solar radiation is significantly correlated with sunshine duration in both East and West China. In East China, the surface solar radiation is significantly positively correlated with the percentage of sunshine. It indicates that the percentage of sunshine duration is the main factor affecting the total surface solar radiation in East China. The decrease of the total surface solar radiation is influenced by many factors. In East China, the percentage of sunshine and the atmospheric turbidity factor are the main factors affecting the surface solar radiation reduction. There is no correlation between cloud and ground solar total radiation. However, the percentage of sunshine is affected mainly by cloud cover and air pollution. In West China, no significant correlation is found between surface solar radiation and cloud cover, but significant correlation is detected between surface solar radiation and sunshine percentage. These indicate that the sunshine percentage could be a main factor affecting surface solar radiation. Wind becomes an important factor affecting the total surface solar radiation, since wind is a main factor expelling troposphere air pollution

  2. Solar walls in tsbi3 user's guide

    DEFF Research Database (Denmark)

    Wittchen, K.B.

    tsbi3 is a user-friendly and flexible computer program, which provides support to the design team in the analysis of the indoor climate and the energy performance of buildings. The solar wall module gives tsbi3 the capability of simulating solar walls and their interaction with the building....... This version, C, of tsbi3 is capable of simulating five types of solar walls say: mass-walls, Trombe-walls, double Trombe-walls, internally ventilated walls and solar walls for preheating ventilation air. The user's guide gives a description of the capabilities and how to simulate solar walls in tsbi3....

  3. In situ built-up air collector with glass cover

    DEFF Research Database (Denmark)

    Kristiansen, Finn Harken; Engelmark, Jesper

    1998-01-01

    with a cover of glass where the horizontal joints were made by means of different methods and materials. As a general principle a water-damming border at the horizontal glass joints was avoided. The test box was built as a solar collector with 14 different horizontal joints between the glasses. The box...... as an absorber. Efficiency and aair pressure drop were measured. The efficiency of the two air solar collectors was almost similar and at the same level as other corresponding air solar collectors. The air pressure drop was somewhat larger in the case of the solar collector where the air flows behind...... the absorber. This is due to the narrower air gap behind the absorber. Condensation has been observed in both the solar collectors, this has not been investigated more explicitly,...

  4. Food dehydration by solar energy.

    Science.gov (United States)

    Bolin, H R; Salunkhe, D K

    1982-01-01

    Solar driers that are currently being investigated for drying of agricultural products can be divided into two major divisions, depending upon how they transfer the incident solar energy to the product to be dried. These two divisions are direct and indirect drying, with some work also being done on combination drying procedures. In direct solar driers, the product to be dried is usually either inside a tent, greenhouse, or a glass-topped box, where the product to be dried is heated by the direct rays from the sun and the moist air is removed by ambient wind movement. These dryers do accelerate moisture loss rate and the product is usually safe from inclement weather. These dryers usually do not require fans for forced air circulation. With indirect drying, the opposite is true, where most require powered fans for forced air circulation. With this type of dryer, both flatplate and inflated tube solar heat absorbers are used, with each offering certain advantages. Also, combination dryers have been built that utilize both direct and indirect principles. Product evaluation of solar dried foods indicate that in most cases the physical properties, flavor, and vitamin A and C retention were as good as, or better than, conventional dried foods. The economics of the solar systems indicate that most drying procedures are economically feasible for use in small-scale operations only, with the exception of grain drying. PMID:7047079

  5. Solar Indices

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

  6. Solar Features

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of solar feature datasets contributed by a number of national and private solar observatories located worldwide.

  7. Solar Imagery

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of solar photographic and illustrated datasets contributed by a number of national and private solar observatories located worldwide....

  8. Solar Indices Forecasting Tool

    Science.gov (United States)

    Henney, Carl John; Shurkin, Kathleen; Arge, Charles; Hill, Frank

    2016-05-01

    Progress to forecast key space weather parameters using SIFT (Solar Indices Forecasting Tool) with the ADAPT (Air Force Data Assimilative Photospheric flux Transport) model is highlighted in this presentation. Using a magnetic flux transport model, ADAPT, we estimate the solar near-side field distribution that is used as input into empirical models for predicting F10.7(solar 10.7 cm, 2.8 GHz, radio flux), the Mg II core-to-wing ratio, and selected bands of solar far ultraviolet (FUV) and extreme ultraviolet (EUV) irradiance. Input to the ADAPT model includes the inferred photospheric magnetic field from the NISP ground-based instruments, GONG & VSM. Besides a status update regarding ADAPT and SIFT models, we will summarize the findings that: 1) the sum of the absolute value of strong magnetic fields, associated with sunspots, is shown to correlate well with the observed daily F10.7 variability (Henney et al. 2012); and 2) the sum of the absolute value of weak magnetic fields, associated with plage regions, is shown to correlate well with EUV and FUV irradiance variability (Henney et al. 2015). This work utilizes data produced collaboratively between Air Force Research Laboratory (AFRL) and the National Solar Observatory (NSO). The ADAPT model development is supported by AFRL. The input data utilized by ADAPT is obtained by NISP (NSO Integrated Synoptic Program). NSO is operated by the Association of Universities for Research in Astronomy (AURA), Inc., under a cooperative agreement with the National Science Foundation (NSF). The 10.7 cm solar radio flux data service, utilized by the ADAPT/SIFT F10.7 forecasting model, is operated by the National Research Council of Canada and National Resources Canada, with the support of the Canadian Space Agency.

  9. Carbon Emissions from air-Conditioning

    Directory of Open Access Journals (Sweden)

    Rajesh Kumar

    2013-01-01

    Full Text Available This paper explores electricity consumption and carbon emissions associated with air-conditioning. The total heat load of a room fitted with air conditioner of 1.5 ton capacity has been calculated by calculating conduction and ventilation losses. Solar heat gain and internal gain were taken as the other two parameters for the total heat calculation.

  10. Solar Equipment

    Science.gov (United States)

    1983-01-01

    A medical refrigeration and a water pump both powered by solar cells that convert sunlight directly into electricity are among the line of solar powered equipment manufactured by IUS (Independent Utility Systems) for use in areas where conventional power is not available. IUS benefited from NASA technology incorporated in the solar panel design and from assistance provided by Kerr Industrial Applications Center.

  11. Solar urticaria

    Directory of Open Access Journals (Sweden)

    Srinivas C

    1995-01-01

    Full Text Available A 35-year-old female and a 41-year-old male presented with clinical features suggestive of solar urticaria. The diagnosis of solar urticaria and the effectiveness of a combination of H1 and H2 blocking antihistamines were confirmed by phototesting with a solar simulator

  12. Qualification test and analysis report: Solar collectors

    Science.gov (United States)

    1978-01-01

    Test results show that the Owens-Illinois Sunpak TM Model SEC 601 air-cooled collector meets the national standards and codes as defined in the Subsystem Peformance Specification and Verification Plan of NASA/MSFC, dated October 28, 1976. The program calls for the development, fabrication, qualification and delivery of an air-cooled solar collector for solar heating, combined heating and cooling, and/or hot water systems.

  13. Solar Activity and the Climate of Prebaikalia

    Institute of Scientific and Technical Information of China (English)

    V. A. Kovalenko; G.A. Zherebtsov; S.I. Molodykh

    2005-01-01

    This paper presents convincing evidence for the reality of manifestations of solar variability in climate characteristics of the Prebaikalia. A numerical estimate is obtained of this influence on ground air temperature. It is shown that the main meaningful variations in air temperature in the region for the period1881-1960 were caused by solar activity. Since the 1960s till the present, with the influence of solar variability continuing, a clear-cut influence of another factor has been observed, the role of which has been steadily increasing, and in the hst decade it has now exceeded the contribution of solar variability. Research results on the variations in hydrological characteristics of Lake Baikal and the Angara river and their connection with solar activity are presented. It is shown that these characteristics are closely correlated with the duration of solar cycles.

  14. Solar Indices - Solar Radio Flux

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Collection includes a variety of indices related to solar activity contributed by a number of national and private solar observatories located worldwide. This...

  15. Application of solar refrigeration technology

    OpenAIRE

    Liu, Yang

    2015-01-01

    With the continuous progress and development, people's living standards increase. Air conditioners, refrigerators and other electrical products are more popular in average families. In summer, people enjoy the fresh air, while electricity costs are staggering. Can I create non-consumption of energy, but also can bring achieve cooling? The answer is yes, now researchers are developing a device using solar energy to refrigeration, to be put on the market, the device not only consumes energy but...

  16. Solar-powered airship. Solar angetriebenes Luftschiff

    Energy Technology Data Exchange (ETDEWEB)

    Knaupp, W. (Zentrum fuer Sonnenenergie- und Wasserstoff-Forschung Baden-Wuerttemberg, Stuttgart (Germany)); Rehmet, M.A. (Inst. fuer Statik und Dynamik der Luft- und Raumfahrtkonstruktionen, Univ. Stuttgart (Germany))

    1994-01-01

    Two solar-powered airships were designed and built within 20 months. The principal aim was to identify ecological alternatives within individual technological fields of air traffic and to demonstrate their feasibility. The project is directed at the design of an ultra-light-weight remote-controlled airship (length 16m) with a video camera for on-line transmission of images and flight data. A particular technological challenge is posed by the design of a light-weight flexible photovoltaic generator and its integration with the airship shell. (orig./BWI)

  17. Solar flair.

    Science.gov (United States)

    Manuel, John S

    2003-02-01

    Design innovations and government-sponsored financial incentives are making solar energy increasingly attractive to homeowners and institutional customers such as school districts. In particular, the passive solar design concept of daylighting is gaining favor among educators due to evidence of improved performance by students working in daylit classrooms. Electricity-generating photovoltaic systems are also becoming more popular, especially in states such as California that have high electric rates and frequent power shortages. To help spread the word about solar power, the U.S. Department of Energy staged its first-ever Solar Decathlon in October 2002. This event featured solar-savvy homes designed by 14 college teams. PMID:12573926

  18. Solar-heating system design package

    Science.gov (United States)

    1980-01-01

    Report describes solar heating system composed of warm-air solar collector, logic control unit, and switching and transport unit, that meets government standards for installation in residential dwellings. Text describes system operation and performance specifications complemented by comprehensive set of subcomponent design drawings.

  19. Solar-heating and cooling demonstration project

    Science.gov (United States)

    1980-01-01

    Florida Solar Energy Center has retrofitted office building, approximately 5,000 square feet of area, with solar heating and air-conditioning. Information on operation, installation, controls, and hardware for system is contained in 164 page report. Document includes manufacturer's product literature and detailed drawings.

  20. Solar Energy: Solar System Economics.

    Science.gov (United States)

    Knapp, Henry H., III

    This module on solar system economics is one of six in a series intended for use as supplements to currently available materials on solar energy and energy conservation. Together with the recommended texts and references (sources are identified), these modules provide an effective introduction to energy conservation and solar energy technologies.…