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In the contemporary global discourse on environmental and developmental issues, the dual challenges of sustainable green energy and water supply stand paramount. These elements are vitally intertwined with the socio-economic vitality of the world. Notably, regions plagued by freshwater scarcity are increasingly turning to desalination which consists of a reliable and unconventional water source. The intersection of renewable energy with desalination and water purification processes presents a compelling synergy. This approach is particularly pertinent in areas where freshwater shortages coexist with abundant solar energy availability. Additionally, these technologies boast the advantage of low operational and maintenance costs. This paper delves into the design, optimization and financial analysis of a novel, standalone hybrid energy system, integrating photovoltaic and fuel cell technologies, for an agriculture farm situated in Kairouan, Tunisia. Unlike conventional systems, this model foregoes battery storage in favour of hydrogen storage, generated through water electrolysis powered by solar energy. This system harnesses solar energy for direct electrical power generation and hydrogen gas production. A segment of the generated electricity is allocated to electrolysis for green hydrogen production. In times of solar unavailability, the stored hydrogen is reconverted to electricity via a fuel cell. An intriguing aspect of this system is the utilization of saline well water, which, due to its high salt content, necessitates purification through desalination to prevent damage to the electrolysis unit and to render it suitable for agricultural irrigation. [Display omitted] • The production of green hydrogen, water and electricity for agriculture farm in Tunisia is analyzed. • The Levelized cost of green hydrogen produced in the PV farm is 2.25 €/kg. • A PV hydrogen Farm station with a capacity of 140 kW produces 1991 kg of green hydrogen and 235 MW h of electricity yearly. [ABSTRACT FROM AUTHOR]

This work deals with an efficient control of the photovoltaic water pumping system. The suggested method is designed by an indirect field-oriented control based on sliding mode control. The sliding mode control is chosen thanks to its various advantages like robustness versus perturbations and uncertainties as well as high accuracy tracking. The contribution is to attest its good performance with the application of a 1-day irradiation profile to achieve a pumping rate with the same variation to prove the control robustness to variation system parameter such as resistor and inductor rotor variation. The least-squares method algorithm is used for the maximum power point tracking (MPPT) adopted to calculate the speed reference of the induction motor drive of the pumping system from the value of illumination. Finally, to improve sliding mode control efficiency with simulation in MATLAB/SIMULINK environment and experimental results, obtained by real-time implementation in a dSPACE 1104 board. [ABSTRACT FROM AUTHOR]

This work presents an experimental validation of MD unit coupled with a sweeping gas membrane (SGMD) using solar energy experimental validation of a sweeping gas membrane distillation (SGMD) unit coupled with solar energy. This station is installed at the University of Kairouan in Tunisia. SGMD is the least used membrane distillation (MD) configuration, and it is very expensive to build. SGMD is used to completely remove solutions containing non-volatile compounds such as salts and recover only high-purity water. A theoretical and experimental study was carried out with the parameters that intervene in the system. The theory of the system is described by a mathematical model based on the heat and mass transfer of the MD unit. Experimental studies were carried out for two types of processes: with preheating and without preheating of the charge (brine). With a low gas flow, the evaporation capacity varies between 0.15 and 0.25 l/m2 h. The operating parameter (liquid velocity) is affected by the layer on both sides of the membrane. Utilizing the water heating by the solar collector increases the evaporation efficiency in the SGMD, and increasing the flow rate the permeate flow in the SGMD. SGMD unit experimental data were submitted to evaluate the reliability obtained from the MD unit, aspects of heat transfer, mass transfer, in solation patterns and all temperatures considering the efficiency of the MD unit. [ABSTRACT FROM AUTHOR]

This paper sheds the light on the future of green hydrogen in Tunisia. So, a detailed economic assessment and evaluation of the Levelized Hydrogen Cost (LHC) and the Net Profit (NP) of a Photovoltaic (PV) Hydrogen Refueling Station (HRS) are presented and discussed. Tunisia is characterized by its high PV potential which makes the production of electricity from solar energy an effective alternative source. However, due to the regulations and issues related to the connection of medium PV scale to the power grid, the energy produced from renewable sources (RS) is still less than 3% of the total produced electricity. On the other hand, the price of hydrocarbon fuels is still increasing. The gap between production and total demand in hydrocarbons has created a deficit in the primary energy balance. Therefore, the production of hydrogen from solar energy for refueling Fuel Cell Vehicles (FCV)s consists of a promising solution to boost the development of the country, reduce hydrocarbon fuels consumption, and protect the environment. The sizing of a small PV-HRS to produce 150 kg of hydrogen per day shows the necessity to install PV systems with a total Direct Current (DC) capacity of 1.89 MWp. The Initial Cost (IC) analysis shows that while the PV system cost represents 48.5% of the total IC, the IC of electrolysers represents 41%. The storage system cost is approximately equal to 3.2% of the total IC. The LHC is equal to 3.32€/kg with a total IC of 2.34 million €. • An economic assessment and evaluation of PV-HRS producing 150 kg of hydrogen in Tunis are presented. • The LHC for the hydrogen produced at PV-HRS is estimated at 3.32€/kg. • The 150 kg PV-HRS has a breakdown of 8 years for a selling price of 8€ per kg of Hydrogen. • The IC and the LHC depend mainly on the prices of the PV panels, electrolyzers, and storage tanks. • Green hydrogen is a promising solution for future transport systems in Tunisia. [ABSTRACT FROM AUTHOR]

Clean energy resources will be used more for sustainability improvement and durable development. Efficient technologies of energy production, storage, and usage results in reduction of gas emissions and improvement of the world economy. Despite 30% of electricity being produced from wind energy, the connection of wind farms to medium and large-scale grid power systems is still leading to instability and intermittency problems. Therefore, the conversion of electrical energy generated from wind parks into green hydrogen consists of an exciting solution for advancing the development of green hydrogen production, and the clean transportation sector. This paper presents a techno-economic optimization of hydrogen production for refueling fuel cell vehicles, using wind energy resources. The paper analyses three configurations, standalone Wind-Park Hydrogen Refueling Station (WP-HRS) with backup batteries, WP-HRS with backup fuel cells, and grid-connected WP-HRS. The analysis of different configurations is based on the wind potential at the site, costs of different equipment, and hydrogen load. Therefore, the study aims to find the optimized capacity of wind turbines, electrolyzers, power converters, and storage tanks. The optimization results show that the WP-HRS connected to the grid has the lowest Present Worth Cost (PWC) of 6,500,000 €. Moreover, the Levelized Hydrogen Cost (LHC) of this solution was found to be 6.24 €/kg. This renewable energy system produces 80,000 kg of green hydrogen yearly. • Wind to green hydrogen represents an interesting solution for greenhouse gas reduction. • Three configurations of wind-park stations designed for green hydrogen production are analyzed. • Grid-connected wind park consists of an optimal solution for the wind park hydrogen station. • The Levelized cost of hydrogen production using a 5 MW grid-connected wind park is 6.24 €/kg. [ABSTRACT FROM AUTHOR]