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The aims of this paper are (1) to evaluate the geothermal resources in Tunisia and (2) to test the deployment of the surface geothermal energy for cooling application. The experiment consists of installing a ground source heat pump (GSHP) system, was carried out in the ‘Centre de Recherches et des Technologies de l’Energie’ (CRTEn) at Borj Cédria, northern Tunisia. The GSHP is composed with horizontal ground heat exchanger (GHE) connected to a reversible geothermal heat pump (GHP), which is connected to a chilled ceiling panel (CCP) system installed in a climate test room. The status of geothermal energy and its utilization are pointed out, the test of the direct use of surface geothermal is examined as well as the evaluation of the GSHP system for air conditioning. The important findings of this study are: (1) Tunisia benefits from important geothermal resources, but its use remains very limited, (2) the only use of the (GHE) has reduced the average temperature inside the climate test room of about 2 °C during 1 day. (3) The test of the GSHP system proves that it is a profitable solution in Tunisia, the coefficient of the performance of the GHP and the whole system are found to be 4.46 and 3.02, respectively. [ABSTRACT FROM AUTHOR]

This paper presents an experimental analysis to examine the performance of a new conic basket geothermal heat exchanger (CBGHE) for greenhouse cooling. This system has never been used or exploited in Tunisia for any research or industrial purposes. Therefore, an experimental system was designed, installed and tested in the Research and Technology Center of Energy (CRTEn) of Borj Cedria. The configuration typically consists of a series of parallel coil implanted in 3 meter depth. The experiments are conducted between 7th and 8th June 2014. The results obtained show that the CBGHE system can be used in the Mediterranean regions such as Tunisia for greenhouses cooling. During the experimental period the maximum quantity of heat transferred to the ground by the CBGHE is about 8 kW. The maximum average temperature difference between the inlet and outlet CBGHE system is approximately 30 °C, with measured mass flow rate of 0.08 kg/s. The air temperature inside the greenhouse decreased of about 12 °C. After the stabilization of the CBGHE system, the performances coefficients of the geothermal heat pump ( COP hp ) and the overall system ( COP sys ) are 3.9 and 2.82, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Impact of users on thermal behaviour of a building and a building''s impact on the use of different spaces are two aspects that are subject of post occupancy evaluation of the present paper. The building was designed according to passive concepts, including Insulated envelope and internal thermal mass; also computer simulations were used to optimize thermal performance of different components of the design. The evaluation was done by using quantitative method to document climate and interior lighting. A qualitative method was also used for analysis of building use and perception of indoor climate by users. High windows were placed in the hall and lobby for night flush to cool the building during summer. However, the difficulty of opening them had led that night ventilation was never practiced. In winter, less window''s areas would be sufficient to satisfy the thermal comfort during the day while ensuring a sufficient level of natural lighting. Daylight level measured in the morning shows that the level of illumination is acceptable; however it remains below the required minimum during the afternoon during fall, winter and spring. Small to medium windows, (4-10% of floor area) on west orientation could improve the daylight during the afternoon. Also, a late closing of the youth club would be desirable for the spring, summer and fall when days are long. The results of the interviews describe a high level of satisfaction from users with regard to indoor climate. Bioclimatic design has a positive impact on the use of the youth. [Copyright &y& Elsevier]