The use of solar thermal energy for air conditioning in buildings has gained interest in the last years. In particular the attention focused on solutions which could lead to the realisation of solar driven de-centralised systems. Technologies implementing thermodynamic open cycles result often suitable for coupling with market available solar systems, since low temperature heat can drive the process. The disadvantage of such systems is the thermodynamic limit of the cycle employed which diminishes the possibility to employ the technology in any condition. Among them the desiccant and evaporative cooling (DEC) systems have been widely studied, for large size air-conditioning plants with compulsory ventilation. But DEC air-conditioning systems are not suitable small size applications, due to technical problems and high costs. A new desiccant-cooling concept (i.e., ECOS) has been developed and is here briefly presented. It is based on a combination of cooled sorption and continuous indirect adiabatic cooling processes. The component where the cycle takes place is derived from a conventional cross flow air-to-air heat exchanger. The cycle offers the chance to overcome the disadvantages of sorption open cycles. The thermodynamic analysis of the cycle and the experimental tests reveals that ECOS extends the range of application in comparison to other implementations of open cycles and moreover performs particularly well in the range of climatic conditions critical for DEC systems (i.e., hot humid climates). During the work reported on this paper an analysis of the performance of the cycle, in terms of COP, has been carried out. Furthermore the efficiency of the whole system (solar and ECOS) has been worked out through the investigation of the SCOP (Solar Coefficient of Performance) characterising the system. The results analysis allowed to draw a picture of the solar assisted air-conditioning system performance and potential application.
A novel high efficient solar assisted sorption system for air building air-conditioning (ECOS): cycle performance and potential application
MOTTA, MARIO;
2005-01-01
Abstract
The use of solar thermal energy for air conditioning in buildings has gained interest in the last years. In particular the attention focused on solutions which could lead to the realisation of solar driven de-centralised systems. Technologies implementing thermodynamic open cycles result often suitable for coupling with market available solar systems, since low temperature heat can drive the process. The disadvantage of such systems is the thermodynamic limit of the cycle employed which diminishes the possibility to employ the technology in any condition. Among them the desiccant and evaporative cooling (DEC) systems have been widely studied, for large size air-conditioning plants with compulsory ventilation. But DEC air-conditioning systems are not suitable small size applications, due to technical problems and high costs. A new desiccant-cooling concept (i.e., ECOS) has been developed and is here briefly presented. It is based on a combination of cooled sorption and continuous indirect adiabatic cooling processes. The component where the cycle takes place is derived from a conventional cross flow air-to-air heat exchanger. The cycle offers the chance to overcome the disadvantages of sorption open cycles. The thermodynamic analysis of the cycle and the experimental tests reveals that ECOS extends the range of application in comparison to other implementations of open cycles and moreover performs particularly well in the range of climatic conditions critical for DEC systems (i.e., hot humid climates). During the work reported on this paper an analysis of the performance of the cycle, in terms of COP, has been carried out. Furthermore the efficiency of the whole system (solar and ECOS) has been worked out through the investigation of the SCOP (Solar Coefficient of Performance) characterising the system. The results analysis allowed to draw a picture of the solar assisted air-conditioning system performance and potential application.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
