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The present work proposes an innovative system for decarbonizing the energy mix and accelerating the worldwide green transition process. The system is driven by a biomass digester integrated with the supercritical carbon dioxide cycle for power generation and a multi-effect desalination unit for drinkable water production. At the heart of this concept is additional hydrogen injection through a proton exchange membrane electrolyzer based on photovoltaic panels. The suggested innovative model's techno-environmental, sustainability, and economic aspects are assessed and compared with a similar system without hydrogen injection. Then, a comparative multi-criteria optimization is applied to find the most optimal conditions from various facets based on the genetic algorithm with machine learning techniques. Afterward, the system’s performance at different optimal conditions is analyzed and compared by evaluating the most significant techno-economic, environmental, and sustainability indicators. The parametric assessment comparing different models indicates that the proposed novel model, including increased hydrogen injection, surpasses the basic system in terms of performance efficiencies, emissions, and energy costs. In the first optimization scenario, the proposed method demonstrates robustness by achieving higher water production of 1456 kg/s, a lower total cost of 118 $/h, and a higher net power of 1.1 MW than the design condition. When considering the sustainability index, energy cost, and emission metric as the optimization objective, their values are altered from 0.81 to 0.85, 92.5 $/MWh to 89.7 $/MWh, and 64.2 kg/MWh to 53.6 kg/MWh. The results further show that when prioritizing the sustainability index, energy cost, and emission as objectives, all components perform better from the energy conversion quality aspect compared to the scenario where water production, total cost, and net power are the optimization objectives. Finally, it is observed that the combustion chamber and solar panels are the worst components from the irreversibility aspect because of the highest exergy destruction rate.

A novel configuration of hybrid wind/biomass energy driven power generation plant is developed and investigated, in which hydrogen is injected into reheat stage of a biomass-fed gas turbine for power generation enhancement and CO2emission reduction. To provide green hydrogen for this purpose, the wind energy is supposed to be employed for electricity production to run a water electrolyzer. Such a hybrid integration of biomass and wind energies will mitigate the biomass shortage and noncontinuous availability of wind energy. Thermodynamic models are implemented to assess feasibility of proposed hybrid plant based on first and second laws. In addition to thermodynamic investigation, economic and environmental evaluations are also carried out. After a parametric appraisal to determine the impact of design variables, single- and two-objective optimizations were conducted to minimize CO2emission index and LCOE. The optimization results revealed that, any change in design conditions for reducing the CO2emissionwill cause in increment of LCOE. It is found that, under final optimum point, developed hybrid power plant attains 0.601kg/kWhand 64.25$/MWh, CO2emission and LCOE, respectively, while the exergy efficiency is calculated to be 39.53%. Also, if the plant is optimized based on single objectives, the lowest values of 63.53$/kWhand 0.590kg/kWhwould be achieved for LCOEand CO2emission, respectively. In addition, the economic analysis in component level indicated that the wind turbine and electrolyzer units have the largest cost rates, respectively as 24.2% and 21.7% of the overall system cost rate.

•Avicennia marinaand Rhizophora mucronatalocations showed significant differences in SBD.•Avicennia marinaand Rhizophora mucronatalocations showed significant differences in SOC concentration.•SOC concentration and SBD had a significant and inverse relationship.•SOC stock of Avicennia marinawas greater than that of Rhizophora mucronataby 114.3%.•Greater mean CSR was noted for Avicennia marinathan for Rhizophora mucronatalocations.

The use of solar energy is vital for the future of meeting the energy demand in the world. Different high- or medium-temperature solar-based power plants have been introduced and examined; however, the low exergetic performance of the solar power-to-electricity process is the principal defect. Although using thermal energy storage in such plants leads to continuous production throughout the day, it also increases the rate of exergy destruction. To improve this deficiency, the present study suggests and studies the simultaneous use of thermal energy storage and compressed air energy storage technologies in a high-temperature soar-based coproduction system by considering a multi heat recovery technique. In this regard, the operation of the system is divided into three periods of the day, namely, storing (low-radiation mode), charging (high-radiation mode), and discharging (night times). Hence, a Brayton cycle equipped with a high-temperature solar field using heliostat mirrors is established. In addition, an organic Rankine cycle is employed for heat recovery. In addition, a low-temperature electrolyzer is utilized for hydrogen generation. The ability of the suggested framework is investigated from the exergetic, sustainability, and financial aspects and is optimized by an advanced evolutionary algorithm. The optimum state indicates that the objective functions, i.e., exergetic round trip efficiency and unit cost of the system, are 26.17% and 0.159 $/kWh, respectively. Furthermore, the electricity capacity and hydrogen production rate are obtained at 7023 kW and 627.1 kg/h, respectively. Moreover, its sustainability index and exergoenvironmental impact index are found at 1.66 and 2.30, respectively.

A hybrid structure of the type Bragg mirror-(Fibonacci)Sis proposed to enhance the zero transmission band through the one dimensional photonic crystal in microwave domain and in the infrared. The efficiency of the configuration is proved in microwave domain for angles below 57°. In the infrared, the use of the configuration exhibits a large photonic band gap at any angle of incidence and for both polarizations. The proposed structure is a quarter wavelength omnidirectional mirror of 37 layers with a bandwidth larger than that of the periodic structure with an increasing ratio 3.7 and it covers all the optical telecommunication wavelengths 0.85, 1.3 and 1.55 m. Unlike the previous devices, the structure is simple to fabricate and it shows interesting optical properties. The configuration Bragg mirror-(Fibonacci)S-Bragg mirror is also investigated to more extend the photonic band gap. Since different physical phenomena have their own appropriate physical scales, we exploited the physical properties of the proposed hybrid structure in different wavelength domains.