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In this work, a new model for producing hydrogen from a low enthalpy geothermal source was presented. Thermal energy from geothermal sources can be converted into electric power by using thermoelectric modules instead of Organic Rankine Cycle (ORC) machines, especially for low geothermal temperatures. This electrical energy uses the water electrolysis process to produce hydrogen. Simulation and experiments for the thermoelectric module in this system were undertaken to assess the efficiency of these models. TRNSYS software is used to simulate the system in Hammam Righa spa, the temperature of this spring is 70 °C. Obtained results reveal that in hammam righa spa in Algeria, 0.5652 Kg hydrogen per square meter of thermoelectric generator (TEG) can be produced in one year.

Algeria has adopted various measures of mitigation and adaptation to adverse climate change impacts. Algerian strategy focus on reducing GHG emissions, CO 2 sequestration, expanding forest areas and improving water resources by sea water desalination. This study presents the GHG mitigation potential of Algeria to 2030, the fossil energy saved through promoting renewable energy and energy efficiency and analyses the main barriers that could hamper the success of this strategy of mitigation and adaptation.

This work focuses on experimental and numerical study of a prototype building to study its thermal behavior and to compare its energy performance with those of a classical home in Algeria. Yearly cooling and heating transmission loads are calculated according to the increase of the thickness of the expanded polystyrene insulation for three different structure materials. The effect of the type of the glazing and the percentage of glazing in the wall has been studied to determine the optimum thickness of the insulation. The results of the thermal simulation showed that the inertia associated with good thermal insulation has an important role in improving thermal comfort and can reach up to 70% energy savings on heating and air conditioning. The results for cooling show that the optimum insulation thickness of expanded polystyrene vary between 1 cm and 2.5 cm, the energy savings vary between 0.5 and 1.5 $/m2 depending on the type and the percentage of the window in the wall.

In this work, a thermoelectric refrigerator is experimented at economic mode working on reduced voltage. The aim of this study is show the performance of a refrigerator alimented with tension lower than 12 V. In this study, we realized a thermoelectric refrigerator in the center of renewable energy CDER at Algiers. Multiple test was done regarding the optimization of energy consumption and achievement of lower temperature possible. The thermoelectric module TEC1-12706 is used for cooling. This TE module can achieve the maximum of efficiency when it function with a tension of 15 V. In our experimental study, we aliment the TE module with a tension of 9 V, the result show that the temperature of 0.5 L in the refrigerator was reduced from 26 to 18 in two hours and the coefficient of performance COP is equal to 0.45. In this work, a thermoelectric refrigerator was manufactured and tested in the laboratory. The experimental study shows that its efficiency is relatively acceptable and that the prototype can operate even at low voltage. At a voltage of 9 V, the COP remains above 0.4 and the temperature in the cooler box is slightly below 14 °C.

In this study, the effect of both high thermal insulation and high thermal mass are investigated numerically using TRNSYS simulation software under steady periodic conditions. This investigation is carried out for a high-energy efficiency home under the Saharan climate conditions of Bechar City. In order to perform this analysis and to achieve the best performance, several external wall configurations are proposed. These configurations are based on changing two aspects; walls construction materials using stabilized earth blocks and clay bricks, and the other one is insulating materials using polystyrene and a new biocomposite insulating material referenced as hemihydrate gypsum/date palm fibers available in Bechar City. The calibration of the model is performed through a comparative study of numerical temperature results with experimental data. Thermal characteristics such as indoor temperature, yearly heating and cooling loads, time lag, and decrement factor are determined for each configuration. The res...

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.

Energy consumption in the building sector reached 43% of national consumption, mainly due to the improvement in the standard of living of citizens, which led to increased use of heating, ventilation and ventilation equipment. air conditioner. Energy efficiency is an appropriate answer to this problem. Actions are needed to influence energy consumption. This article presents the results of a study of a newly built office building at the Center for the Development of Renewable Energy (CDER) in Algiers. This building obeys the norms of the Algerian thermal regulation. The annual energy requirements for heating and cooling are 2754 kWh and 3575 kWh respectively. the heating of the building is provided by a solar thermal system, with a field of solar collectors with a surface of 10 m². the indoor office temperature reaches a certain comfort and varies between 10.8 ° C and 23.4 ° C TRNSYS software is used for dynamic simulation of building performance.

The efficiency of the parabolic trough solar plant depends to various parameters such as the storage design system, the used solar fluid and collector design. This paper presents an investigation study of the effect of the variation the aperture and focal width on the produced energy. In this context, a design of parabolic trough solar plant has been proposed. This solar plant is intended to install in Touggourt region, which is located in South-Eastern of Algeria. The results show that the proposed solar plant has six months of high energy production. The energy production increases with the increases the aperture width respected a low focal with value. The best-proposed design has large of aperture width and the smallest focal distance.

This study presents the thermal analysis of a building prototype, which was designed and built in accordance with energy efficiency measures to improve indoor thermal comfort, particularly in summer. The building prototype is located in Souidania (20 km southwest of Algiers, latitude 36°7N, Longitude 03°2E). The location is characterized by a temperate Mediterranean climate. In order to perform this analysis, various activities are carried out: a series of monitoring campaigns; dynamic simulations with TRNSYS software, calibration of the model with experimental data and comparative study with buildings that use different wall constructions. Based on a validated building thermal model, dynamic analysis is carried out in order to evaluate the impact of thermal mass and of eaves and night ventilation. The results demonstrate that cooling energy demand is more affected by thermal transmittance values than by the envelope thermal mass. A recommended guideline for the optimum overhang length for south-facing windows is proposed. Ultimately, it is found that the combination of both natural ventilation and horizontal shading devices improves thermal comfort for occupants and significantly reduces cooling energy demand.

The study provides a detailed analysis of the energy production and consumption in Algeria and the associated CO2 emissions. Algeria is an important energy producer (oil and natural gas). The production is currently around 155 MToe. The total primary energy consumption amounted to about 58 MToe equivalent to 1.46 Toe/capita. The energy demand is still increasing, an average annual growth rate of more than 6% per year during the last decade. The growth rate for electricity production was almost twice that of the total energy consumption. In 2015, the installed capacity of the electricity generation plants reached 17.6 GW. Electricity consumption was 64.6 TWh and is expected to reach at least 75 TWh in 2020 and 130 TWh in 2030. The already high electricity demand will double by 2030. In the structure of final energy consumption, the transport sector ranks first (36%), natural gas consumption ranks second (28.5%), followed by electricity production (27.7%). By activity, the energy sector is the main source o...

Algeria is one of the sunniest countries in the world and therefore solar energy is the most promising alternative energy source that can contribute strongly in the reduction of its energy consumption especially in residential sector. This paper investigates the energy performance of a solar water heating system under Algiers climate conditions. Two different models of storage tank are studied; fully mixed tank and stratified tank. A parametric study was performed in order to determine the optimum size of the thermal collector, storage tanks and mass flow rate. The optimized systems was used to simulate the annual energy performance of the solar water heating system under Algiers climate conditions. The simulation results show that the solar fraction of the solar system with a stratified storage tank is very important (96%) than the solar fraction in the case of a fully mixed tank (88%).

The study area is one of the important geothermal provinces in south Algeria. It is characterized by a hot arid climate with intense dryness and very high evaporation rates. The Albian geothermal system is exploited by the wells mainly for domestic and agricultural purposes. The sandstone Continental Intercalary (CI) formation constitutes the reservoir for the Albian aquifer, covering an area of 600,000 km2. This reservoir is covered by calcareous formations which yield the chemical characteristics of highly mineralized Na-Cl type representing the deep thermal waters and Ca-SO4 type determined the presence of evaporate lithology . For a better understanding of geothermal reservoir characteristic, a multidisciplinary approach was adopted, including hydrogeochemistry and geothermometry. More than fifty samples collected from wells recently in 2017 with a temperature average between 38 and 60° C and conductivities range from 2010 to 3460 μS/cm. Geochemical analysis of those thermal waters exhibits a certain degree of salinity with sodium-chloride type waters domination. The maximal geothermal reservoir temperature estimated using geothermometry is about 120°C.

In northern Algeria, use of ventilation by ceiling fans is widespread in mosques and other public buildings during the hot season, but is seldom used in private houses. In the first part of this study, the impact of this mode of cooling on indoor thermal comfort is investigated. A thermal comfort model for transient conditions is developed in order to calculate an instantaneous thermal comfort index. In order to simulate the thermal behaviour of a human body as accurately as possible, the latter is divided into 17 segments and a heat balance equation is written for each segment. The results indicate that even during hot days, an appreciable thermal comfort can be achieved if ventilation at constant air speed is used. Moreover, it is shown that it is not necessary to increase ventilation speed beyond a given level, as thermal comfort gains become negligible. In the second part of the study, the impact of solar radiation on thermal comfort is evaluated. Thermal sensation of a human being partially exposed to direct solar radiation is calculated. The results show that a discomfort sensation is quickly felt when a person is exposed to sun fluxes, which confirms the importance of shading devices.

The present work studies the Barra–Costantini passive solar heating system, with particular emphasis on the aspect of economics. The system which is studied is developed by Barra and Constantini. This system seems to be well adapted to the climatic and economic conditions in Algeria. In the first part of this work, an ideal model representing the thermal behavior of a room provided with the heating device is elaborated. The results of this model are compared with the results of an experimental study carried out on an Italian site. Initially, the model was used to determine the temperature variation for the different elements of a room with the Barra–Costantini (B-C) system. The model is then used for conditions corresponding to several Algerian sites. This study makes it possible to quantify the energy savings obtained by the addition of the B-C system to a traditional gas heating system. The introduction of a ratio between the cost of energy and the cost of equipment makes it possible to conclude that only the intervention of the authorities can make the passive solar system economically viable.

In this study, the heating and cooling energy consumptions for houses located in Algiers are determined using the degree day method during one year.Analytical results are validated by simulation with TRNSYS software. The hourly curves for energy consumption and outside temperature are presented during one month, one week and one day periods. Moreover, monthly results during a year are presented and analytical values are compared to simulated values. The degree day method proved to be applicable to the monthly and annual energy analysis for buildings. It was found that, Algerian climate with its long warm season compared to the cold season, consumes cooling energy twice as much as the heating energy. Energy consumption for heating reaches 670 kWh, as for cooling it is 1700 kWh.