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This work analyzes the performance of a new Integrated Collector Storage Solar Water Heater (ICSSWH) by using Dynamic System Testing (DST) method according to Standard ISO 9459‐5. The long‐term performance study of the system in different climatic conditions has been achieved by a coupling model between DST results and a numerical approach based on the system transient behavior. Results of the experimental dynamic system evaluation showed that the total store heat capacity Cs, the useful collector surface Ac* and the storage tank heat losses coefficient Us are, respectively, 0.87 MJ/K, 1.21 m2 and 10 W/K. In Tunisian climatic conditions, the ICSSWH system allows covering until 79.3% from a typical family need for a daily consumption of 170 L. The results found allow optimizing the energy gain of the ICSSWH as well as selecting a specific load volume according to the location. Especially, investigations showed that in Stockholm and Riadh climatic conditions, the ICSSWH's solar fraction reached 27% and 83%, respectively, for a daily load volume of 250 L. More importantly, the experimental effort of DST identification can be minimized by coupling DST data with a robust numerical approach. [ABSTRACT FROM AUTHOR]

Summary: Solar tower power plant technology is based on the principle of concentrating incident solar irradiation on a receiving surface located at the top of the tower via a mirror field. The heliostat field consists of a significant number of reflective mirrors; each heliostat tracks the Sun individually and reflects the Sun's incident rays at a focal point. Therefore, the heliostat position plays a major role in the global system efficiency and must be carefully chosen to minimize optical losses. In this paper, a mathematical model was proposed for the analysis of the optical efficiency of the solar tower power plant. Detailed optical losses are mainly losses by blockage, shading, spillage, and atmospheric mitigation. During this study, the approach was oriented toward the optical study of the solar thermal power plant: a new method for calculating the blocked and shaded surface has been developed. This new method was then validated basing on the database of the marketed solar power plant PS10 installation with a north heliostat field configuration geometry, as well as a validation was elaborated based on a surrounding heliostat field configuration geometry. Obtained results show that the individual heliostat efficiency is in the range of 0.824; based on published papers, the calculation error factor is in the order of 0.01%. Numerical results of the shading and blocking efficiencies prove the reliability of the developed model. In the first hand, the model is valid whatever the heliostat parameter (its row, heliostat orientation, its position according to their neighbor, etc). On the other hand, the developed model is applicable in all heliostat field configurations; it is valid in both surrounding and north configurations. [ABSTRACT FROM AUTHOR]