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This paper presents a study on energy performance of an earth air heat exchanger (EAHE) for buildings in Maghreb climatic context (Oran, Bechar and Adrar cities in Algeria). In order to check the influence of the material, two air conducts (one of galvanized sheet metal and the other in polyvinyl chloride–PVC) are considered under the same geometric conditions (a 20 m conduct length, 120 mm diameter and 2 m burial depth). They are used separately for the ventilation in simple current flow of two adjoining rooms constituting a test cell located at the university campus IGCMO-USTOMB (Oran, Algeria). An experimental device has been set up to measure the temperature at different points (air inlet/outlet air duct). Measurements were run in August 2015, and the monitoring of both exchangers allowed us to evaluate their cooling performance: 35.41% for the Zinc pipe and 58.42% for the PVC pipe. Experimental results were compared to those obtained from the simulation (under the Trnsys 16) and a fair similarity is obtained. In order to optimize the energy performance of the exchanger (EAHE), numerical simulations are carried out by varying different parameters: climate, burial depth, length and diameter of the duct. Other simulations have shown that the energy supplied by the cooling exchanger (EAHE) is more significant in the south of the country (Adrar and Bechar) than in the north (Oran). [ABSTRACT FROM AUTHOR]

Solar radiation is a renewable non polluting energy source which can be used in buildings through various systems technologies. Thermal radiation, absorbed or transmitted by the walls and windows, creates a solar gain which has a direct impact on the thermal behavior in the building. Most existing thermal models neglect the effect of the evolution of the sun patch position on the heating floor which can have a great impact on the indoor thermal comfort. In this paper, we present numerical model to calculate the transient sun patch position and its influence on the heating floor model in order to evaluate its impact on the heating floor operating conditions and on the indoor air temperature, which has a great influence on thermal comfort under the climatic conditions of Oran city in Algeria. The sun patch is calculated using Ray Tracing model as proposed in FLUENT whereas the room and the heating floor are modelled with TRNSYS software. Using literature data, the two proposed models (sun patch model and heating floor model) are validated and used to simulate the cases with different geographic locations and different window orientations, surfaces, and positions. Our results suggest that the displacement of the sun patch on the heating floor lead to a superheating of the irradiated zone and it affects the indoor air temperature and thermal comfort too. [ABSTRACT FROM AUTHOR]

The future of masonry buildings with heritage values is certain – the investments in making such buildings energy-efficient during renovations to meet the energy consumption requirements will increase over the next decade. However, decision makers fail to address the concerns of each project actor and give specific answers on how basic requirements on such historical buildings can be implemented. This paper proposes a new multi-criteria group decision-making method for the thermal renovation of masonry buildings. The aim of the proposed method is to rank different renovation solutions. The method uses; the structured group interaction method Delphi to define the evaluation criteria and the thermal renovations solutions, Swing method to facilitate the process of the determination of the criteria weights, the group decision support system (PROMETHEE GDSS) to reach a global ranking of the renovations solutions, PROMETHEE V to introduce additional constraints, as well as the Graphical Analysis for Interactive Aid (GAIA) analysis to get a better understanding of conflicts and similarities between the criteria and among the decision makers. We proceed to exemplify by means of a real-life case project in Algeria and offer suggestions on what front-ended stakeholders could do to reduce the energy consumption in masonry buildings. [ABSTRACT FROM AUTHOR]

Nowadays, it is well recognized at the international level that the building sector is one of the biggest energy consumers, which made the intervention in this sector the greatest potential for energy consumption reduction and greenhouse emissions mitigation. In Algeria, building sector is responsible of more than 40% of the final energy consumption. Solar energy systems integrated in buildings can be an important solution to this dual problem. The aim of this paper is to estimate the energy performance of a typical single-family bioclimatic house equipped with a solar heating system located in the north Algeria (Algiers) and to investigate its conversion into a zero energy house by installing a grid connected PV system. To achieve this goal, a numerical model of the bioclimatic house coupled with the solar heating system is developed and validated with experimental data. Then, the validated model is used to optimize the adequate size of the solar heating system and to determine its contribution in the production of thermal energy for both DHW preparation and space heating of the house. Finally, a PV system is sized to supply, in parallel with the utility grid, the house with electricity for lighting, appliance and auxiliary electric heater. Furthermore, an economic analysis is made to show the profitability of integration of grid connected PV and solar thermal systems in building. Results show that the conversion of a bioclimatic house into a ZEH using a grid connected PV system, in the north of Algeria weather conditions, present high level of feasibility. However, the return on investment is very high due mainly to the high cost of solar energy components and the very low costs of conventional energy in Algeria. [ABSTRACT FROM AUTHOR]