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The objective of this paper is the investigation of the annual performance of a solar power plant with linear Fresnel reflectors in the El-Oued region at Algeria. The solar collectors produce water steam that feeds a turbine to produce electricity. The System Advisor Model (SAM) tool is used for simulation. The mean net daily electricity production rate from 8:30 am to 5:30 pm is 48 MWe, and the respective annual production is 210,336 MWh/year. The mean daily optical efficiency of the solar field was close to 52%, while the mean thermal efficiency was about 39%. The net daily cycle efficiency is found to be 24%. The net capital cost of the examined system is $393 million, and the developer net present value is $47 million; the investor net present value is $15 million, the entire period of capital recovery is 11 years, and the levelized cost of electricity is 0.0382 $/kWh. The solar power plant leads to the yearly avoidance of 420,672 tons carbon dioxide emissions (operational cost savings of $6.1 million). Based on the obtained results, linear Fresnel reflectors can be used to achieve satisfying, energetic, financial, and environmental performance that can lead to sustainability. [ABSTRACT FROM AUTHOR]

Going forward towards developing and improving renewable energies in Algeria is one of the main objectives of this study, especially, solar energy that is an exceptional and continuous source of energy. Algerian Sahara has a large area suitable for agriculture, but not connected to the electricity network. Therefore, the construction of solar power plants based on the solar energy concentration has been proposed for the electricity production, which is exploited in the rest of the economic sector of the Algerian state. Through the study conducted under real weather data for the day March 16th, 2018, an optical characterization of a solar power plant of parabolic trough concentrator has been convoyed in El-Oued region, Algeria. The geometrical and the optical characteristics of studied solar collector have been determined, such as the optical efficiency, the local concentration ratio, the cosine effect of the incidence angle, the optical losses at the ends of the receiver tube, the shading effect, the blocking effect, and the coefficient of incidence angle modifier and intercept factor. MATLAB code has been used as a program for numerical programming. Of the most important results obtained, it was found that the optical efficiency has exceeded 77.22 %. As for the local concentration ratio, its maximum value is equal to 116.30 in the lower part of the receiver tube at the peripheral receiver angles "ß=91° and 269°", while the minimum values of this important coefficient were recorded at the top of the receiver tube. [ABSTRACT FROM AUTHOR]

In this study industrial grade Multi-walled carbon nanotubes (MWCNTs) nanoparticles dispersed in distilled water (DW) are investigated to evaluate its impact on the thermal behavior of linear Fresnel solar reflector technology. The stability and thermophysical properties of the MWCNTs/DW nanofluids are obtained experimentally. Stable nanofluids that showed higher thermal conductivity compared to DW were obtained. Thermal conductivity (TC) of the nanofluids increased by 3%, 6% and 7% for the volume fractions of 0.05%, 0.1% and 0.3% at 25 °C, respectively. TC also increased with the increase in temperature (i.e. 11% for 0.3% volume fraction at 70 °C). A one-dimensional model is developed to evaluate the transient behavior of the nanofluid within the linear solar reflector. Matlab code based on the finite difference method is developed to solve the energy balance equations at the different components of the studied solar collector. The numerical model is then validated with experimental results, where a maximum experimental thermal efficiency of 29.205% at 14:00 is achieved. MWCNTs/DW nanofluid with 0.3% volume fraction has the highest thermal efficiency of 33.81% and the highest PEC value as well as the lowest entropy generation. • Small linear Fresnel reflector has been manufactured and experimentally tested. • The maximum experimental thermal efficiency of DW is equal to 29.205%. • Stability and thermophysical properties of the MWCNTs/DW nanofluids are obtained. • Thermal conductivity of the nanofluids increased with the increasing volume fractions. • Highest thermal efficiency of 33.81% was obtained for MWCNTs/DW nanofluid. [ABSTRACT FROM AUTHOR]

The concentrating solar systems of linear Fresnel reflectors offer the ability to generate electricity from solar energy. The main objective of this paper is to perform a transient numerical simulation on a linear Fresnel solar reflector directed to produce superheated water steam for the power plants, in order to determine its efficiencies (optical and thermal), where the heat transfer fluid mass flow inside the copper absorber tube is 0.045 kg/s. The dimensions of the studied linear Fresnel solar collector are the same dimension as the modular system Nova-1 of NOVATEC SOLAR Company. The dimension of the studied model is 1D. For this purpose, El-Oued region has been designated as a study field. The twelve recommended average days for months have been selected for the study. This paper was based on a numerical solution using the finite differences method. MATLAB has been used as a software language. The optical efficiency of the LFR solar receiver has reached 53.7% where the thermal efficiency has reached 37.5%, while the pressure drop within the absorber pipe has reached 02 bars. As for superheated steam temperatures variations, it ranged between 233.35 °C and 263.75 °C, knowing that the water steam inlet temperature when entering the absorber tube is equal to 140 °C. As for the overall coefficient of heat loss, its mean value is 5.84 W/m2.°C. The results obtained are very encouraging to invest in this steam power plant, especially in the desert areas, which are rich in solar energy. Image 1 • Optical efficiency of the solar reflector obtained was 53.7% • Thermal efficiency of the solar reflector achieved was 37.5% • An annual electricity capacity of more than 2000 MW can be produced • This technique is 100% clean and has no negative environmental impact [ABSTRACT FROM AUTHOR]