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Abstract: This Hybrid Energy System (HES) is mainly based on proton exchange membrane fuel cell (PEMFC) technology, which is supplied by a fuel reforming process for hydrogen production, starting from natural gas. The aim of this paper is to analyse the feasibility study of a process by combining a low-temperature geothermal source with a PEMFC subsystem (PEMFCS). This analysis allows the development of an onsite independent Hybrid Energy System used for air-conditioning, and especially the use of hot water for space cooling. PEMFC technology with an LiBr/H2O absorption system has been introduced to provide fresh air by a cooling process in a school canteen for 240 students, located in the western region of Algeria. The feasibility study shows that combining geothermal sources and PEMFC technology for air-conditioning production constitutes a promising solution. [Copyright &y& Elsevier]

Abstract: The diffuse part of solar radiation is one of the elements necessary for the design and evaluation of energy production of a solar system. However, in most cases, when radiometric measurements are made, only global radiation is available. To remedy this situation, we present in this paper, an analysis of the scattered radiation measured on a horizontal surface for three sites in Algeria namely: Algiers, Tamanrasset and BŽchar. We propose in this article models to determine the hourly ratio diffuse radiation/Global radiation received by a horizontal surface. The correlations established for the chosen sites were compared to the work of Liu and Jordan (1960), Orgill and Hollands (1977), Erbs et Al (1982), DT Reindl (1990) and Chendo (1994). The performances of our models were evaluated by conducting two statistical tests on the estimated diffuse fraction of solar radiation. The first test concerns the simplified comparison of the composite Residual Sum Squares (CRSS). In the second test, we calculate the mean absolute error (MAB). The new correlations presented in this study provide a significant improvement by reducing the standard error compared to existing models in the literature at a rate exceeding 40%. [Copyright &y& Elsevier]

Abstract: PV systems connected to the electricity distribution network, also called grid-connected PV power stations (CPVCR), is one of the applications of photovoltaic solar energy the most developed in recent years in the world .The purpose of this paper is the study of such a plant. It is the development of a method of characterization, analysis and modeling of each part of the plant allowing for easy practice of engineering such systems and assess the impact of the widespread this type of application on the electricity grid. This work will also develop a method to forecast the behavior of energy and economic CPVCR in Algeria. [Copyright &y& Elsevier]

Abstract: The Municipal Solid Waste Management (MSWM) is one concern of cities in the world, notably in Algeria and specifically in the city of Chlef. Local authority faced these difficulties have more and more problems to bring local solutions to support an ever growing stream of waste. This support needs to organize the collection and sorting of waste generated by households, and the relevant elimination procedures other than dumping in landfill. The recycling of biodegradable materials by composting may be a possible way. Prior to justify this choice and to quantify the expected benefits for the environmental and agronomic areas, it is essential to proceed with the characterization of the MSW. Based on the zoning of the current collection of household waste as well as the sectorization of the different collection zones, sampling was performed on the dump trucks arriving on the controlled landfill of Meknassa, situated 9km from the center of the city. The method of characterization used is adapted from MODECOM (Method of Characterization of the household waste, the protocol recommended by ADEME in France), which distinguishes three size distribution fractions, big:> 100mm, medium: 100-20mm, fine: <20mm, and 13 categories (organics, paper, cardboard, plastics .). This operation is repeated for five zone of the municipality of Chlef, out of 5 campaigns spread over two years (2010-2011) according to the seasons. After this complete and detailed characterization of MSW collected in Chlef, and taking into account the biodegradable organic matter and humidity contents, the composting could be a solution for the region of Chlef which agricultural activities will be a natural outlet to compost product. [Copyright &y& Elsevier]

Abstract: Talking about the concept of “environment” means treating a multidisciplinary and interdisciplinary theme which revives a simultaneous consideration of multiple data social, economic, natural. To date, the protection of the environment as a whole becomes a challenge for many countries, policies for the preservation, education and scientific research strategies are aimed at the environment and sustainable development. It remains an idea of its young problem, still current. It is development that meets present needs without compromising the ability of future generations to meet their own needs. In the field of architecture and urban planning, environmental protection is an important place. With the growth experienced by this area, several environmental procedures have been invented to improve the quality of construction and use of buildings, a view mainly environmental but without neglecting the economic and social aspects. The environmental protection has long existed, it is found in the experiences of ancient cities such as Ksours. This legacy is an inspiration and an asset for the sustainable development of our cities today. According to Hassan Fathy only in the tradition, we respect and we continue the work of previous generation that new generation can really move and solve the problem. The materials used the distribution of space, protection of natural resources such as water and palm trees, recycling, are the strategies of the company of Ksours to live in a healthy and comfortable space. The objectives of this paper are: To highlight the history of environmental policy in architecture and urbanism in the world, in this case Ksours. Renewable energy and strategies of the preservation of the environment in the Ksours Sustainable development in Ksours: a notion that has long existed. Establish strategies to protect the environment. [Copyright &y& Elsevier]

Abstract: Thermal comfort plays a major factor in building infrastructure sector. It has a big impact on building interior temperature as well as on energy balance and environment. In the current paper the influence of thermal isolation, building orientation and thermal inertia of building envelop on interior ambient temperatures have been studied. To meet our objective, a methodological procedure has been followed. It consists of elaboration of computing program written in MATLAB code to simulate the proposed mathematical model. The main objective of the proposed mathematical proposed model is to compute different delivered temperatures under real climatic and environment conditions. Confrontation of the results found through simulation with those found experimentally shows a clear consistence. Thus the theoretical model is experimentally validated. It can be concluded that: The most effective measure to achieve a better results is thermal insulation. The orientation of thermally isolated building doesn’t have a considerable impact on interior temperature. Thermal inertia of buildings may thus generate thermal comfort. It was revealed that an adequate use of stone thermal inertia is essential to achieve a better building thermal comfort. [Copyright &y& Elsevier]

Abstract: Today, innumerable damages caused by the city and the action of a man on built and natural environments, are recorded in majority of developed countries and also under development ones, which had created in the last few years, complex problems difficult to solve like: pollutions, destructions of natural and rural landscapes, uncontrolled rejections of waste, problems of water and frequent variations of the climate. Algerian cities haven’t escaped to this truth and this situation is related with the history of the development process adopted in Algeria, during the years of post independence. The development of these cities was done without looking for or respecting environmental requirements. Theoretically, Algeria has a complete building formed by different plans and schemes covering environment, land use planning and urbanism fields to raise this challenge and avoid errors of the past, particularly before nineties and after, by adopting a holistic approach and giving a broadest sense of environment protection. But until now, just a few great actions recently carried out by the ministry of land use planning, environment and tourism are registered, and the rest confirms that these tools don’t have any effect suspected on ground, for various causes. The most important causes can be resumed in the lack of dialogue and coordination efforts between concerning actors and theirs institutions, and the absence of an explanation relating to the whole approach able to make these tools even they were appeared in different laws, working as a united body. That''s why these instruments were ineffective and the situation became difficult and critical. The present paper will focus on this reality. [Copyright &y& Elsevier]

Abstract: Wind turbines installed in Saharan climate operate often under severe weather conditions. Particularly, the electric/electronic equipments located within the nacelle may be subjected to extremely high temperature. To maintain acceptable temperature levels inside the nacelle and control efficiently the thermal effect, cooling systems should be used properly. This paper presents a numerical method to investigate the nacelle thermal behaviour of wind turbines operating under extremely hot weather conditions. The air flow in and around nacelle is described through the Reynolds averaged Navier-Stokes equations. The energy equation has been used to account for heat transfer effects. A Control-Volume Finite Element Method has been used to solve the resulting governing equations. The simulations have been performed through a typical commercial wind turbine. Results including temperature fields in and around the nacelle have been obtained and showed quite reasonable behaviour. Mainly, the impact of an appropriate cooling system that can be designed and applied in nacelle thermal control is presented and discussed. [Copyright &y& Elsevier]

Abstract: Renewable energy in food industry and particularly in drying process is growing and mainly in developing countries. Solar energy is often used by direct products exposure through a glass or to heat drying air through a solar collector. However, the random and intermittent nature of solar radiation leads to use conventional energy sources as supplement. Hence, optimization and design tend to reduce the drying time of products for minimum possible energy use. These cases are often preceded by rigorous energy and exergy drying process analysis. That is the aim of our work in this paper. The used dryer is an indirect type, passive, without extra energy and discontinuously operating. It is composed of a solar air heater and a drying room. The experiment took place at Bouzareah on the heights of Algiers in the summer season. The choice of mint is because its abundance and its wide use in Algeria. Using the first and second principles of thermodynamics, we could estimate useful energy received by the heater and that really used during drying. Energy analysis has allowed us to quantify the solar energy received by solar heater and available for drying. Exergy analysis has allowed us to estimate the energy losses during the drying process. [Copyright &y& Elsevier]

Abstract: This paper shows the modelling of a domestic solar water heating installation. The results of simulations performed on daily basis for a solar system (collector with surface of 2 m2 and a storage tank of 200 litres), operated in Constantine (Algeria), which provides hot water for heating. The installation consists in a solar flat collector, a water storage tank, a source of auxiliary energy and radiators. We analyse more accurately the influence of the thermosiphon-flow rate and consequently the stratification degree of the tank on the water heating system performances. The interest of this study resides in the approach used to model the tank and in the analysis of the number of the nodes used on the gained energy. [Copyright &y& Elsevier]

Abstract: Wind resources present a promising option to be integrated with the conventional energy sources to match the increased demand of electricity. This paper aims to investigate the possibility to set up a wind farm of 10 MW in Adrar, a region located in the south of the country. Using the wasp software, the wind resources of the zone of interest was performed, it indicates that wind speed reach 8.44 m/s at a height of 80 meters. Then, two sites Kaberten(75 north of Adrar) and Zaouia (80 Km south of Adrar) were selected. The wind farm study show that Aouia present the better performance, it can be expected to achieve from this site a production of 40 GW and a full load hours about 4044h. [Copyright &y& Elsevier]

Abstract: This paper presents an investigation of a direct evaporative air cooler (DEAC) under Algerian climate, at the city of BECHAR. We carried out the theory and design of the DEAC. Simulation is done for an evaporative air cooler for three successive months June, July and August under TRNSYS environment. Measured weather data of the selected site are generated by METEONORM software. Result showed that the maximum depression of the dry bulb temperature reached is about 18.86°C and the Energy Efficiency Ratio (EER) is calculated. Evaporative cooling equipments work well in the hot and arid southern regions, which constitute practically the two third of the country. They have no impact whatsoever on the environment. Energy consumption is much less than in classical air conditioning units this is why these systems can be powered by solar photovoltaic panels. [Copyright &y& Elsevier]

Abstract: The In Salah CO2 storage project in Algeria, initiated in 2004, provides a unique early-mover case study on CO2 storage. After 5 years of operation, the project has developed a substantial storage-unit characterisation and monitoring dataset. The question we address in this paper is: which reservoir features have proven most critical in controlling the injection performance so far? This is also an important question for future CO2 storage sites, as part of the planned global ramp-up in CCS as a greenhouse gas mitigation option. Our main findings are that structural geological and rock mechanical aspects are most critical in the early injection phase, while characterisation of the pore space, combined with the dynamically created fracture permeability, becomes more important when considering the medium to long-term effects (10–1000 years) including geochemical, fluid dynamical and geomechanical aspects. When considering the quantity and type of data that are needed to sufficiently characterise this CO2 storage site, high quality 3D seismic proves to be highly valuable (despite its relatively high cost). For the pore space characterisation, core samples from both the reservoir and the caprock are vital in order to calibrate and properly interpret static and dynamic well data. Finally, monitoring datasets, including well-head gas and tracer data, time-lapse seismic data, and satellite (InSAR) monitoring data need to be interpreted and only bring true value when utilised with detailed geological descriptions and models of the subsurface. [Copyright &y& Elsevier]

Abstract: This paper presents a structured qualitative approach to analysing the varied kinds of information from a CO2 storage site, so as to produce scenarios that are amenable to numerical analysis. The approach is illustrated by application to an industrial scale CCS project at Krechba, In Salah, in Algeria. A structured approach is needed to support assessments of the likely performance of CCS systems over operational, monitoring and longer term time-frames. Very varied information concerning such systems’ engineered and environmental components must be obtained and evaluated to attain sufficient confidence that performance will be acceptable. Computer simulations and risk assessment models are needed to help understand the behaviour of CO2 and place plausible bounds on the temporal evolution of all aspects of the system. The outcomes will be uncertain, even if underpinning data sets are of good quality The approach included identification of the important the Features, Events and Processes (FEPs) that together describe the Krechba system and its likely evolution. An ‘expected evolution’ scenario was then identified by systematically evaluating existing knowledge. Scenarios describing potential situations that could involve alternative evolution mechanisms were also identified; these included consideration of mechanisms that could in principal lead to containment failure. These scenarios need to be analysed to show that they are either unlikely to occur and/or will be of limited impact and so do not represent threats to adequate performance. After audit against Quintessa’s freely available generic online CO2 FEP database to ensure and demonstrate comprehensiveness, the site-specific scenarios identified and the associated list of remaining uncertainties, were used to prioritise future (e.g. systems modelling) work. The outcomes of this and other data analysis and modelling programmes will be used to update the FEP and scenario descriptions. [Copyright &y& Elsevier]

Abstract: In the paper we share our operational experience gained from three sites: Sleipner (14 years of injection), In Salah (6 years) and Snøhvit (2 years). Together, these three sites have disposed 16 Mt of CO2 by 2010. In highly variable reservoirs, with permeability ranging from a few milliDarcy to more than one Darcy, single wells have injected several hundred Kt of CO2 per year. In the reservoirs, the actual CO2 plume development has been strongly controlled by geological factors that we learned about during injection. Geophysical monitoring methods (especially seismic, gravity, and satellite data) have, at each site, revealed some of these unpredicted geological factors. Thus monitoring methods are as valuable for reservoir characterisation as they are for monitoring fluid saturation and pressure changes. Current scientific debates that address CO2 storage capacity mainly focus on the utilization of the pore space (efficiency) and the rate of pressure dissipation in response to injection (pressure limits). We add to this that detailed CO2 site characterisation and monitoring is needed to prove significant practical CO2 storage capacity–on a case by case basis. As this specific site experience and knowledge develops more general conclusions on storage capacity, injectivity and efficiency may be possible. [Copyright &y& Elsevier]

Abstract: The Krechba field is one of several gas fields located in the Algerian Sahara desert, and was set in operation in August 2004 as part of a joint venture with BP, Sonatrach and StatoilHydro. The natural gas in the fields contains up to 10% CO2, which has to be reduced to 0.3% before the gas is sold, resulting in the production of around 1 million tonnes/year CO2. Rather than vent the CO2 to the atmosphere (business as usual), it is re-injected into the water leg of the Krechba Carboniferous Sandstone gas producing reservoir (20 m thick) via three horizontal wells at a depth of around 1,900 metres. CO2 injection started in August 2004 and to date nearly 2.5 million tonnes of CO2 have been injected, amounting to approximately 25% of the gas extracted from the Krechba field over the same period. A number of key technologies to monitor the injection, and the subsurface movement and storage of CO2 have been, and will continue to be, deployed to provide long term assurance of sequestration. Time lapse satellite images (using PSInSARTM Technology) which measure ground deformation to assess the movement of CO2 in the subsurface have proven to be much more successful than initially thought, despite the depth of injection and the low voidage replacement rate (25%). Satellite images collected since start of injection show clear increases in ground elevation of up to 30mm around the three injectors while subsidence is also apparent in the area of maximum gas production. The images have also confirmed the CO2 is moving in the direction of preferred fracture orientation at reservoir level. Recent downhole pressure measurements in one of the injectors also indicates that the CO2 is being contained within the injection horizon. Work is ongoing to integrate the satellite images with geomechanical and seismic data to better understand how these images can be used for monitoring of CO2 movement in the subsurface. A key part of the forward monitoring programme will be the acquistion of time-lapse 3D seismic, deployment of tiltmeters and GPS to confirm and calibrate the satellite imagery data, microseismic detectors in shallow boreholes to assess the degree of rock strain and use of shallow wells to monitor the water chemistry in the vadose zone. These will supplement the ongoing tracer, wellhead sampling and satellite imagery data acquistion. This paper shares the latest results of the ongoing CO2 monitoring project. [Copyright &y& Elsevier]

Abstract: In Salah Gas Project in Algeria has been injecting nearly one million tonnes CO2 per year over the past four years into a water-filled strata at a depth of about 1,800 to 1,900 m. Unlike most CO2 storage sites, the permeability of the storage formation is relatively low and comparatively thin with a thickness of about 20 m. To ensure adequate CO2 flow-rates across the low-permeability sand-face, the In Salah Gas Project decided to use long-reach (about 1 to 1.5 km) horizontal injection wells. In this study we are using field data and coupled reservoir-geomechanical numerical modeling of CO2 injection to analyze geomechanical responses and to assess the effectiveness of this approach for CO2 storage in relatively low permeability formations. Among the field data used are surface deformations evaluated from recently acquired satellite-based inferrometry (In SAR). The In SAR data shows a surface uplift on the order of 5 mm per year above active CO2 injection wells and the uplift pattern extends several km from the injection wells. We use the observed surface uplift to constrain our coupled reservoir-geomechanical model. We conduct sensitivity studies to investigate potential causes and mechanisms of the observed uplift. Preliminary results of our analysis presented in this paper indicates that most of the observed uplift magnitude can be explained by poro-elastic expansion of the 20 m thick injection zone, but there could also be a significant contribution from pressure changes within the adjacent caprock. Moreover, we show that surface deformations from In SAR can be useful for tracking the fluid pressure and for detection of a permeable leakage path (e.g. in a permeable fault) through the overlying caprock layers. [Copyright &y& Elsevier]