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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]

This work aims to enhance the heat transfer of a small prototype linear Fresnel reflector by using rGO-Co 3 O 4 /water hybrid nanofluids at a location in Blida region, in Algeria. Hybrid nanofluids, with varying concentrations (0.05, 0.10, and 0.20 wt%) and temperatures (20–60 °C), are prepared. For 0.2 wt % of rGO-Co 3 O 4 nanofluids, the viscosity and density increased by 70.83%, and 0.47%, respectively, while the specific heat decreased by 0.17% at a temperature of 60 °C over the base fluid data. The receiver pipe energy balance equations are solved using MATLAB software. With the use of 0.2 wt% of hybrid nanofluid, the mean thermal efficiency enhanced by 2.75%–31.95%, the mean exergy efficiency improved by 23.67%–2.27%, and the mean temperature increased by 9.42 °C, while, the receiver pipe temperature decreased by 2.69 °C. In addition, the mean heat transfer coefficient, mean thermal conductivity, Nusselt number, and the performance evaluation criteria were improved by using rGO-Co 3 O 4 /water nanofluid at 0.2 wt % by 309.67%, 19.31%, 254.75%, and 240.92%, respectively, while the mean entropy generation and electrical energy consumption decreased by 59.48% and 20.30%, respectively, as the CO 2 emission mitigation was 253.94 kg. Image 1 • Stable rGo-Co 3 O 4 /Water hybrid nanofluids with excellent thermal properties was experimentally obtained. • Thermal conductivity increased by 19.14% at 0.2 wt% for 60 °C using hybrid nanofluids. • Thermal behavior of hybrid nanofluids was investigated in a small LFR. • LFR thermal efficiency enhanced by 2.75%–31.95% using rGo-Co 3 O 4 /Water with 0.20 wt %. • Mean performance evaluation criteria using rGo-Co 3 O 4 /Water with 0.20 wt % enhanced by 240.92%. [ABSTRACT FROM AUTHOR]

In order to understand the behavior and to determine the effective operational parameters of a solar-driven ejector air conditioning system at low or medium temperature, a dynamic model depends on the principles of conservation, the momentum mass and energy is developed. For this purpose, the thermodynamic characteristics of the liquid and vapor refrigerant were identified using the Engineering Equation Solver (EES) software. Linear Fresnel solar reflector has been used as a tool to convert solar energy into thermal energy. Water (R718) was used as a refrigerant. The operational conditions for the studied solar-driven ejector air conditioning system are as follows: evaporator temperature "Te =283.15 K", condenser temperature "Tc =305.15 K", and generator temperature "Tg = 373.15 K". The performance of the ejector air conditioning system was compared as a function of the operating parameters of the subsystem. The average value of thermal efficiency of the Fresnel linear concentrator has reached 31.60 %, the drive ratio "ω" is 0.4934, the performance value of the ejector air conditioning subsystem "COPejc" is 60.664 % and the average value of the thermal performance of the machine "STR" has touched 19.17 %. The results obtained through this scientific subject are stimulating and encouraging, where this technique can be used for air conditioning in desert areas in southern Algeria, where fossil energy (petroleum, gas, etc.) is extracted and produced in various types. [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]