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The study explores the impact of surface orientation and tilt on incident solar irradiation. It was conducted in M'Sila, an Algerian province, from February to June. A number of experiments were carried out using an experimental setup consisting of a heliometer and a slant changer, which allowed for the variation of the tilt angle. Nineteen tilt angles ranging from 0° to 90° were investigated for the four main directions: North, South, East, and West. The obtained outcomes were statistically analyzed. At east and south orientations, incident solar irradiance rose as a function of tilt angle, reaching a maximum at the optimal angle, and then gradually decreased. Generally, the incident solar irradiance decreased as the tilt angle increased in the case of west and north orientations. The tilt angle of the exposed surface as well as the sun's elevation in the sky affected the amount of intercepted energy significantly at each orientation (p<0.05). When the sun was low in the sky, the south orientation was most preferred for an inclination greater than or equal to 25°. The north-facing surfaces with steep slopes (β ≥ 55°) received the least amount of solar radiation. These results hold great importance, particularly in the building sector, as they can be utilized to achieve energy saving. [ABSTRACT FROM AUTHOR]

Dust accumulation on PV surface panels is a crucial factor affecting their performance. It is more frequently noted in the desert zones. The effect of dust on the electrical behavior of damaged PV panels was investigated in this study. Three panels are used: the degraded panels (with and without dust) and the reference panels; they are located in an industrial zone with a continental climate (Bordj Bou Arréridj, Algeria). The I-V and P-V characterization and degradation mechanism visualization are used. Also, a numerical simulation was conducted to calculate the five parameters of the three modeled PV panels (diode ideality factor (a), series resistance (Rs), Shunt resistance (Rp), photocurrent (Ipv), and diode saturation current (I0)). These parameters were utilized for the first time to study the impact of dust on their degradation rate and the PV panel behavior. The degradation rate and the annual degradation rate of each parameter are affected by dust differently. The power degradation rate is increased by 5.45%. The Isc and Imax degradation rates are climbed by 6.97% and 6.0%, respectively. Vmax and Voc degradation rates decrease by 1.20% and 0.35%, respectively. Dust increased the rate of degradation for a, Iph, and I0 by 4.12%, 6.99%, and 68.17%, respectively. For Rs and Rp, the degradation rate was reduced by 4.51% and 20.01%, respectively. An appropriate netoiling approach must be considered because dust, even in non-desert areas and industrial zones, has a significant impact on the electrical characteristics degradation of a PV panel. [ABSTRACT FROM AUTHOR]

In this study, the design, analysis and optimization of the performance of a concentrated solar power plant that is based on the parabolic trough technology with a capacity of 100 MW equipped with a thermal energy storage system were conducted, in two representative sites in Algeria (Tamanrasset and M'Sila). The System Advisor Model software is used to evaluate the technical and economic performances of the two proposed power plants, in addition to carrying out the process of optimizing the initial design of the two power plants by finding the optimal values of the solar multiple and full load hours of the thermal energy storage system, with the aim of increasing the annual energy production and reducing the levelized cost of electricity. The results of the performance analysis conducted on the optimized design showed that the optimum values of the solar multiple and full load hours of the thermal energy storage system for the proposed power plant at the Tamanrasset site were found to be 2.4 and 7 h, respectively, with an annual electricity production of 514.6 GWh, and a minimum value of the levelized cost of electricity of 6.3¢/kWh. While the optimum performance of the proposed plant at the M'Sila site can be achieved by selecting a solar multiple of 3 and 7 h for thermal energy storage system, with a high annual energy production of 451.84 GWh and a low value of the levelized cost of electricity of 7.8¢/kWh. The results demonstrate that CSP plants using parabolic trough technology can increase energy security in the country, while reducing environmental concerns associated with the use of fossil materials. [ABSTRACT FROM AUTHOR]

Global solar radiation is needed for the analysis and scaling of solar conversion systems; however, global measurements of solar radiation are not available in all Algerian cities. The use of empirical models using an accessible parameter is a solution to this problem. In this study, seven empirical Models namely Hargreaves and Samani, Chen, M.F. Li, H.Li, Bristow and Campbell, Okonkwo and Abraha Savage have been employed to estimate daily average global solar radiation on the horizontal surface. These models use extreme temperatures (minimum and maximum). They were applied to three south Algerian sites (Biskra, Ghardaia, and Tamanrasset). The analyzed data were provided by the NASA site and cover four years (2001-2004). The validation of the models for predicting daily global solar radiation was done using four statistical parameters (R2, MBE, RMSE, and RPE). The results show that Bristow and Compbell Model shows better performance than the other models in all sites. A new model is proposed for each site. The results show that this later is the best one compared with the seven models analyzed. Therefore, the developed model can be suggested to estimate daily global solar radiation using only extreme air temperatures in south Algeria.

In this study a steady flow-field and heat transfer through a copper-water nanofluid around a circular cylinder, under the influence of both the standard thermal boundary conditions, i.e., uniform heat flux and constant wall temperature) was investigated numerically by using a finitevolume method for Reynolds numbers from the range 10-40. Furthermore, the range of nanoparticle volume fractions considered is 0-5%. The variation of the local and the average Nusselt numbers with Reynolds number, and volume fractions are presented for the range of conditions. The average Nusselt number is found to increase with increasing the nanoparticle volume fractions. [ABSTRACT FROM AUTHOR]