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Solar flat plate collectors are commonly used to transform solar energy into thermal one by heating a heat transfer fluid (HTF). The available thermal energy to the user is characterized by a certain thermal capacity and a certain temperature level. Comparing to the case of a single collector, when a higher thermal capacity is required in the user process, more collectors should be coupled in parallel, so that the HTF mass flow rate is increased, exiting the solar collector at the same temperature. Another case may be encountered when the user process requires the same mass flow rate of HTF, but at a higher temperature. In this last case, a series connection is considered. The aim of the present paper is to compare these cases and to build a solar panel map that could be used to choose the best arrangements for a specific user need. A study is performed regarding the map dynamics with respect to HTF consumption to the user for three storage tank capacities of 100L, 200L and 300L respectively. The results reveal a recommendation regarding collectors coupling function on user needs. [ABSTRACT FROM AUTHOR]

This paper describes the development of a small-scale solar simulator for research and educational purposes. The main goal is to provide a uniform and stable distribution of irradiation from a set of four floodlight halogen lamps, over a targeted area of 40x40 cm². The floodlights are placed perpendicularly to each other, on the top end of a light tube. Two types of halogen lamps were characterised and the total irradiation of the solar simulator was measured over a 5x5 grid. The results showed that the two arrangements of lamps are able to achieve a level of 1000 W/m² on the 40x40 cm² targeted area, but the non-uniformity is unsatisfactory. In order to reach a non-uniformity level of 10% using the proposed lamps arrangements, the targeted area should be reduced to 31x31 cm². [ABSTRACT FROM AUTHOR]

The paper presents a comparative analysis of two solar powered systems aiming to produce electricity. The potential user could be a duplex house or an office building. One system consists of an Organic Rankine Cycle (ORC) modeled to operate at variable mass flow rate, constraint by the heat source temperature which is provided by a parabolic dish collector. The second one is a Stirling engine modeled by taking into account the internal and external irreversibilities, using the concentrated solar radiation from dish collector, too. Both engines have to deliver the same electrical power (constraint), according to the user's daily energy consumption profile. The study considers the daily solar radiation and ambient temperature variation under cloudy sky conditions, and the receiver heat losses dependence on these data. The analysis results emphasize the required solar collector dimensions in each case. The comparison is done to previous obtained results under clear sky conditions. [ABSTRACT FROM AUTHOR]