• Energy Research

Abstract Potou is an isolated site, located in the northern coast of Senegal. The populations living in this area have no easy access to electricity supply. The use of renewable energies can contribute to the improvement of the living conditions of these populations. The methodology used in this paper consists in Sizing a hybrid solar–wind-battery system optimized through multi-objective genetic algorithm for this site and the influence of the load profiles on the optimal configuration. The two principal aims are: the minimization of the annualized cost system and the minimization of the loss of power supply probability (LPSP). To study the load profile influence, three load profiles with the same energy (94 kW h/day) have been used. The achieved results show that the cost of the optimal configuration strongly depends on the load profile. For example, the cost of the optimal configuration decreases by 7% and 5% going from profile 1 to 2 and for those ones going from 1 to 3.

Abstract Despite the remarkable potential for biogas production from livestock and organic wastes, the number of constructed biogas digesters for the continent is in the order of thousands and in case of Mauritania is lower than the number of the provinces. While majority of the existing digesters left far behind the expected efficiency, lack of a comprehensive economic assessment along with an efficient design questions their practical application. The present study introduced the first assessment to evaluate the biogas potential from livestock manures and waste from slaughterhouses in Northwest Africa (a case of Mauritania). Using ArcGIS® software, a database was conducted to build maps that show the amount of waste products, the potential of biogas, and equivalent amounts of energy. These were used to assess the potential of biogas and the corresponding potential energy for each geographical department in Mauritania. The results indicated that the southern provinces had the highest biogas potential with the maximum and the average values of 520 and 258.7 (±125.8) × 106 m3/year. On the other hand, the lowest biogas production potential (27.7 × 106 m3/year) was recorded for northern provinces with the maximum and the average values of 135 and 76.4 (±39.7) × 106 m3/year. The results showed that 63,579 × 106 kg of waste associated with livestock (cattle) and slaughterhouse applications were annually produced in the country. It was determined that this quantity could generate 2451 × 106 m3 of biogas per year, corresponding to an energy potential of 52,704 × 106 MJ/year. Considering the rapid depletion of conventional energy sources and the significance of biogas as a renewable fuel, a detailed feasibility analysis (for the biogas production in each province of Mauritania by means of community type fixed-dome digesters) was also performed in the scope of this study. The results of the comprehensive cost breakdown analysis revealed that the revenues obtained from sale of biogas-generated electricity and digested slurry (as fertilizer) could able to pay the initial investment within approximately 6.5 years without subsidy. The findings of this study, as the first of its own, could be used to comprehend how utilization of information such as slaughterhouse and livestock population, nutrition habitats, land-usage maps and geographic information system (GIS) can be employed to germinate a model for more comprehensive assessment of biogas production potential from livestock manure and slaughterhouse wastes, specifically in case of northern African countries. Moreover, in case of biogas plant, this model could be employed as a decision-making tool to identify the highly qualified location for construction of the biogas plant.

AbstractThis paper presents a methodology to size and to optimize a stand-alone hybrid PV/Wind/Diesel/Battery bank minimizing the Levelized Cost of Energy (LCE) and the CO2 emission using a Multi-Objectives Genetic Algorithm approach. The main objective of this work is to study the influence of the load profile variation on the optimal configuration. The methodology developed was applied using solar radiation, temperature and wind speed collected on the site of Gandon located in the northwestern coast of Senegal. Results show that, for the all load profiles, as the LCE increases the CO2 emission decreases. For the all solutions, the LCE was lower for the load profile 3 than for the load profiles 1 and 2.

AbstractThe objective of this paper is to propose a methodology for designing a stand-alone hybrid PV/wind/diesel/battery minimizing the Levelized Cost of Energy (LCE) and the CO2 emission using genetic algorithm. The methodology developed was applied using solar radiation, temperature and wind speed data, collected on the site of Gandon, located in the northwestern of Senegal. Obtained results were presented as optimal Pareto front. The optimal number of devices, the Levelized Cost of Energy (LCE) and the CO2 emission were determined for each solution. An influence study of the size of diesel generator on the optimal configuration was carried.

AbstractThe aim of this paper is to determine the wind energy potential for electricity generation in the northwestern coast of Senegal. The wind characteristics and wind energy potential in eight sites (Kayar, Potou, Gandon, Sakhor, Sine Moussa Abdou, Botla, Dara Andal and Nguebeul) are analyzed using the wind speed data collected during a period of one year for each site. The annual mean wind speed and the power density were computed. Results obtained show that the annual mean wind speed varies between 5.28 m/s in Potou (at 30 m) and 3.10 m/s in Dara Andal (at 7 m). The corresponding power density varies between 120.01W/m2 and 30.05W/m2 respectively.A technical assessment of electricity generation from three big wind turbines and from three small wind turbines was carried out. Results show that the highest capacity factor was 39% observed in Sokhar for the wind turbine Yellow- Sand, whereas the lowest capacity factor was 5% in Gandon for the wind turbine Ecotecnia 80. The highest output energy was 4,517,900k Wh/year in Sokhar for the wind turbine Repower, while the lowest output energy was 312 kWh/year observed in Gandon for the wind turbine Inclin 600.

The main target of this paper is to determine the seasonal features of the wind speed in the northwestern of Senegal and to assess the cost of annual energy output using wind turbines provided from several manufactures. The wind data used for this study were collected in four sites located in the northwestern coast of Senegal and cover the period of one year. The seasonal mean wind speed and the annual distribution curves were obtained by using the Weibull distribution function. A technical assessment of electricity generation from five big wind turbines which power is between 640 kW and 2000 kW and from six small wind turbines which power is between 250 W and 10 kW were carried out. The results obtained show that the lower cost (0.0265 €/kWh in Sokhar) was observed for the wind turbine Ecotècnia 62. The highest cost was 0.5103 €/kWh (in Gandon) observed for the technology of Alize. All wind turbines was better suited to the site of Sokhar with the highest capacity factor and the lowest cost of output energy.

A new approach for sizing a hybrid solar-PV-battery and biogas generator for power generation was suggested in this study, based on the variation of energy resources and the load profile. Biogas has enormous potential and numerous economic and social advantages. In this respect, the monthly solar radiation, temperature, and biogas produced from biomass resources were used as model inputs. This study considers the total annualized of the components for the feasibility analysis. HOMER Pro® software-based outcomes in the proposed methodology revealed that the proposed solar biogas hybrid system was sufficient to meet the load requirements of the village (Ain Farba village in the Hodh El Gharbi area located in the northeast of the Mauritania country) with a net present cost over the 25-year lifespan of 61,144 $ and the energy cost was determined to be 0.0473 $/kWh.

This paper is aimed at determining the diurnal characteristics of the wind potential inSenegal. The data used in this study are collected from eight sites (Kayar, Potou, Gandon, Sine Moussa Abdou, Botla, Dara Andal, Nguebeul and Sakhor) located alongside the North-western coast of Senegal. These data cover the period of one year for each site. The annual wind speed distribution curves in all sites were obtained by using the Weibull distribution function. The results obtained show that the power density available is greaterduring the dry season than in the rainy season. In all sites, it appeared more important for the day-time than the night-time. For instance, the power density was 145.30 and 58.34 W/m² at the height of 20 m in the day and night, respectively in the site of Potou; it reveals 99.64 and 52.35 W/m² in the site of Kayar and 103.14 and 45.87 W/m² in Gandon during the same period and the same height. The corresponding average wind speeds are of 5.69 and 4.15 m/s in Potou, 5.04 and 3.80 m/s in Kayar and 5.13 and 3.77 m/s in Gandon. Key words: Weibull distribution, wind potential, diurnal characteristics, seasonal characteristics.