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A scheme has been proposed, modeled and simulated to show an improved system efficiency, battery life and payback period of a 340 kWp peak power grid interactive solar photovoltaic system. In this case, a conventional solar photovoltaic system capable to fulfill 66% energy demands has been modified to meet complete energy demands without an increase in system's photovoltaic capacity. It has been shown via modelling and simulation on PVSyst that using direct current appliances instead of alternating current appliances, initial power demands are reduced by 58% and conversion losses (DC-AC-DC) of 9.6% are eliminated. These modifications result in an overall increase in the system's performance ratio from 73.8 to 83.4%, with an increase in energy production from 469.6 to 557.9 MWh. As an outcome, battery life is increased by 1200 duty cycles as the depth of discharge is reduced from 35 to 26%.

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This study presents the effect of incorporating synthesized metakaolin on the compressive strength of standard mortars for a constant water/binder ratio of 0.5. Synthesized metakaolin mixtures with cement replacement of 5, 10, 15 and 20% were tested. From the results, it was observed that 15 % replacement level was the optimum level in terms of compressive strength. Beyond 15 % replacement levels, the strength was decreased but remained higher than the control mixture. Compressive strength of 52 MPa was achieved at 15 % replacement. This investigation has shown that it is possible to produce high strength mortars using local kaolin.

This paper seeks, as a part of Algerian policy, to encourage the reconstruction of the ground in order to achieve economic reconstruction and the safety of inhabitants and the environment. The study focuses on the hygrothermal behaviour of compressed and stabilised earth blocks that can be used in different climate zones, like the south of Algeria, where the temperature is up to 50°C in summer, and the coastal towns, where humidity exceeds 80%. Accordingly, an experimental study has been conducted to determine the influence of temperature on the sorption isotherms for compressed and stabilised earth blocks stabilised with 6% of cement. The sorption isotherms were measured at temperatures of 10, 23, 30, 40 and 50°C. Twelve equations have been fit to the experimental isotherms to find the one that gives the best agreement. An experimental model was then developed based on the Oswin model describing the dependence of temperature on the sorption characteristics of compressed and stabilised earth blocks. The results show a significant influence of the increase in temperature on the hygrothermal behaviour, in particular a reduction of 11% in the equivalent water content between 10°C and 50°C.

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The aim of this work is to examine the thermohydric behavior of a building made of compressed stabilized earth bricks (CSEB), by testing its effectiveness in stabilizing the quality of indoor air, compared to four conventional materials. The study is carried out using TRNSYS-COMIS software with its Buffer Storage Humidity Model for three types of climates: desert, Mediterranean, and dry and cold semi-arid climate. The results highlight the contribution of the CSEB material in regulating the indoor relative humidity of buildings, also in limiting the effects of condensation thanks to its adsorption effect.

This study tested the effectiveness of some natural ventilation basic configurations for the thermal comfort of occupants in different local climates in Algeria. Due to the diverse Algerian climate, the study was performed during the mid-season period that includes three months of May, September, and October and the summer that includes the months of June, July, and August. The ventilation potential of the selected configurations was analysed through numerical simulation by using TRNSYS software coupled with COMIS aeraulic software. The results showed the significant contribution of natural chimney ventilation caused by a stairwell to improve occupant comfort. However; its integration requires a judicious and permanent inspection to control temperature decreases or overheating risks.