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This paper presents a bi-level approach to support retailers in making investment decisions in renewable-based systems to provide clean electricity. The proposed model captures the strategic nature of the problem and combines capacity sizing decisions for installed technologies with pricing decisions regarding the electricity tariffs to offer to a reference end-user, representative of a class of residential prosumers. The interaction between retailer and end-user is modeled using the Stackelberg game framework, with the former acting as a leader and the latter as follower. The reaction of the follower to the electricity tariff affects the retailer’s profit, which is calculated as the difference between the revenue generated from selling electricity and the total investment, operation and management costs. To account for uncertainty in wholesale electricity prices, renewable resource availability and electricity request, the upper-level problem is formulated as a two-stage stochastic programming model. First-stage decisions refer to the sizing of installed technologies and electricity tariffs, whereas second-stage decisions refer to the operation and management of the designed system. The model also incorporates a safety measure to control the average profit that can be achieved in a given percentage of worst-case situations, thus providing a contingency against unforeseen changes. At the lower level, the follower reacts to the offered tariffs by defining the procurement plan in terms of energy to purchase from the retailer or potential competitors, with the final aim of minimizing the expected value of the electricity bill. A tailored approach that exploits the specific problem structure is designed to solve the proposed formulation and extensively tested on a realistic case study. The numerical results demonstrate the efficiency of the proposed approach and validate the significance of explicitly dealing with the uncertainty and the importance of incorporating a safety measure.

The dish stirling technology holds great promise as a renewable energy solution for remote and off-grid electric regions, particularly in the southern areas of North Africa. In this research, we conducted simulations of a 100 kw Dish Stirling system to evaluate its feasibility in comparison to photovoltaic technology at five distinct locations in southern Algeria: Adrar (Bordj Badji Mokhtar), Illizi (Djanet), Tamanrasset (Ain Mertoutek), Tindouf, and Bechar. Our findings underscore the substantial potential of Dish Stirling Solar Power technology, with the Sahara region standing out as particularly promising. In this region, the Dish Stirling system consistently outperforms a 100 kw photovoltaic system across all selected locations. The Dish Stirling system achieves an average annual electricity generation of 256 mwh while simultaneously mitigating CO2 emissions by 177 tons annually. Among these locations, Djanet Illizi emerges as the most favorable, with the Dish Stirling system producing an impressive 288.43 mwh annually. This capacity is sufficient to meet the annual energy needs of 230 households, all while maintaining a competitive LCOE of 0.0378 USD/kwh. Comparative analysis with previous research illuminates the remarkable cost-effectiveness of Dish Stirling technology in southern Algeria, primarily due to its abundant direct normal irradiance levels. These findings underscore the immense potential of Dish Stirling systems as a clean and highly efficient energy solution, well-suited for demanding to address the energy needs of remote environments, such as those found in the southern border regions of Algeria.

In this paper, density functional theory (DFT) calculations are performed to investigate the spin-dependent mechanical, electronic, magnetic, optical, and thermal transport properties of rare-earth-based chalcogenides MgPr2X4 (X = S, Se) spinels. The mechanical properties are obtained by employing the modified Perdew-Burke-Ernzerhof generalized gradient approximation (PBEsol GGA). Also, the modified Becke and Johnson (mBJ) potential is engaged in examining the electronic, magnetic, optical, and transport properties. Structural stability in the ferromagnetic (FM) phase is confirmed by calculating the energy difference between the FM and non-magnetic states. Besides, the formation energies are computed for thermodynamic stability. The strong hybridization near the Fermi level comes from chalcogenides 2p-states and f-states of rare-earth metals, which results in the total magnetic moments. The in-depth optical properties are evaluated in terms of dielectric constant and refraction. Lastly, electronic thermal coefficients, such as Seebeck coefficient, electrical and thermal conductivity, and power factor, are also probed and suggested studied spinels as promising sustainable energy materials.