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Abstract: In the last few years the solar-powered air-conditioning systems have been in intensive development and more often are considered as the viable application for the thermal solar systems in the regions of southern Europe. This is mainly due to the increasing higher electrical consumption in many countries (especially in Spain) which is moving from the winter to summer months due to expanding usage of cooling systems in this period of the year. In this paper we will analyze the behaviour of the solar-assisted air-conditioning system installed in the CIESOL building. This system consists mainly of flat-plate solar collectors and the simple effect LiBr–H2O absorption chiller. Different operation modes were analyzed. Coefficient of performance (COP) at various generator, absorber, condenser and evaporator temperatures is investigated and experimental results show that in practice it is easy to obtain values of about 0.6. The main goal of this paper is to describe the characteristics of the developing building and the solar-assisted air-conditioning system. Another useful purpose is to find the optimum conditions and operation parameters for the solar system through analyzing various systems'' operation strategies. [Copyright &y& Elsevier]

Abstract: Numerous computer programs are available to calculate the energy efficiency of buildings. Many are based on the use of a reference building to determine the degree of efficiency. However, this methodology presents a major constraint when assessing a building after construction and during the use stage. To assess the energy efficiency of buildings, this paper proposes new indices based on energy consumption during different periods; as well as other parameters of the buildings such as construction area, number of users, and air-conditioned volume. Results are presented as an application for various buildings on the campus of the Universidad Politécnica de Valencia. [ABSTRACT FROM AUTHOR]

Rooftop gardens ona building have proved to be a good way to improve its storm water management, but many other benefits can be obtained from the installation of these systems, such as reduction of energy consumption, decrease of the heat stress, abatement on CO2 emissions, etc. In this paper, the effect from the presence of these rooftop gardens on abuilding's energy consumption has been investigated by experimental campaigns using a green roof ona public building in a Mediterranean location in Spain. The obtained results demonstrate a substantial improvement by the installation of the green roof onthe building's cooling energy demand for a standard summer day, in the order of 30%, and a reduction, about 15%, in the heating energy demand for a winter day. Thus, given the longer duration of the summer conditions along the year, a noticeable reduction on energy demand could be obtained. Simulation analysis, using commercial software TRNSYS code, previously calibrated using experimental data for typical summer and winter days, allows for the extrapolation to the entire year of these results deducing noticeable improvement in energy efficiency, in the order of 19%, but with an increase of 6% in the peak power during the winter period. [ABSTRACT FROM AUTHOR]