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This paper aims to show factors that have a direct impact on solar air conditioners that use the ejector as an alternative to the compressor to reduce electricity consumption in the refrigeration field. The weather data of the Blida region were selected as the main data for conducting this study. A parabolic trough solar collector has been made as a solar device to provide the thermal energy needed for the generator. All the mathematical equations that dominate the system have been analyzed and then numerically simplified using Engineering Equation Solver software. The optical efficiency of the studied solar collector was 65.02%, while its maximum value of thermal efficiency was only 60.46%. Regarding the thermal ratio of the studied machine, it reached 0.54. Serious exploitation of this technology will help solve the problem of high consumption of electricity in the hot seasons and also contribute to the preservation of the environment by using water (R718) as a refrigerant.

An experimental and numerical study on the solar water heater is carried out in Blida area, Algeria during winter in this work. Numerical results are confirmed by experimental results, where the numerical results are presented in two forms: Numerical solution based on estimated equations of climatic data and numerical solution based on actual values of weather data. Finite difference method was used to analyze and simplify energy balance equations. Results obtained showed a significant convergence between experimental and numerical results, where optical efficiency has passed 42.65 %, while the highest value for thermal efficiency was 29.212 % on February 22, 2015, while its average exergy efficiency for February 19, 2015 is 1.81 %. Experimentally, the maximum value of hot water temperature reached 352 K on February 19, 2015. As for the volume of water heated by the studied collector, it is 0.4 m3/day. The system performance is 19.75%, the equivalent of an electrical capacity of 545.68 kWh. Economically, the LFR reflector cost is 378.87 $, where this cost can be recovered after sixteen years of the first use, as the cost of heat generation is 0.043 $/kWh. Environmentally, the CO2 mitigation is 247.14 kg. Additionally, this reflector will provide the equivalent of 127.47 m3 of Liquefied natural gas.

This paper aims to examine the optical behavior of a small experimental setup for linear Fresnel reflector. The setup was built and tested as a water heater at University of Blida located in Algeria. All the optical factors of the studied solar system have been taken into account, such as the intercept factor, the longitudinal coefficient of incidence angle modifier, the transverse coefficient of incidence angle modifier, the concentration ratio and the optical efficiency. For this reason, a numerical model is proposed to determine optical parameters. In addition, SolTrace modeling was used to confirm the numerical results obtained. The results obtained showed that the number of the reflective mirrors has a direct impact on the optical efficiency of the device, where the average values of the optical efficiency exceeded 42.65%, 35.82% and 26.98% for 11, 09 and 07 mirrors. In addition, the concentration ratio is increased proportionally with the number of the reflective mirror, where the average values of this factor exceeded 9.77, 8.64 and 6.74 for 11, 09 and 07 mirrors, respectively. Keywords: Solar energy, Linear fresnel solar reflector, Optical behavior, SolTrace modeling, Numerical simulation