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The dwindling reserves of fossil fuels have spurred the expansion of photovoltaic power systems, widely regarded as an alluring solution. Yet, a formidable challenge arises when it comes to optimizing the output of PV systems exposed to irregular irradiance stemming from external environmental factors. Consequently, this research endeavors to advocate the use of the Moth Flame Optimization (MFO) algorithm to search for the highest power output of a solar energy harvesting system. The distinctive behavior of moths proves instrumental in thorough searching of the feasible space, mitigating the risk of entrapment in local optima. To evaluate its efficacy, this algorithm’s performance is validated by comparing its outcomes with those of the Butterfly Optimization Algorithm (BOA). Both algorithms are subjected to experimentation to search for the Global Maximum Power Points (GMPPs) of the PV system under two distinct Partial Shading Condition (PSC) scenarios: Case 1 and Case 2. The results indicate that BOA tends to produce outcomes with a broader data dispersion range relative to the mean, unlike MFO. Specifically, for Case 1, the standard deviation values for MFO and BOA are 2.327040E−02 and 5.777913E−02, respectively, while for Case 2, they are 5.0567340E−02 and 8.519362E−02, respectively. Hence, the proposed approach demonstrates faster and more precise convergence.

The reduction of operation and maintenance costs as well as the improvement of reliability of wind energy conversion systems are of top priorities in the renewable energy industry as the demand for wind energy continuously grow tremendously. With that, the condition monitoring system (CMS) plays a crucial role in maximizing the potential of wind energy in generating electricity. Therefore, this review paper vividly captures the fact that the recent advancements in embedded control in CMS in wind energy conversion systems are able deliver tangible benefits to the renewable energy technology (RET) industry as a whole. It is proven that CMS based maintenance is deemed to be more suitable in multiple aspects with fewer drawbacks, as compared to scheduled and corrective maintenance. In this review paper, an attempt to evaluate the viability of CMS is being made. The main purpose is to shed some light on the significant contributions provided by CMS in shortening the downtime and increasing the production rate of the wind energy conversion system. Forthcoming promising applications with good potential to surpass the recent dilemmas were also explored and analyzed at the end of this paper.

The wind energy sector has grown significantly over the past several decades as enabling technologies advance. One of the major reasons of such rapid growth is due to the renewability of this eco-friendly energy source that reduces carbon footprints worldwide. The overall costs of large scale wind energy conversion systems can be extremely high, which is deemed to be one of the main dilemmas stakeholders have to face with during the design phase. Generators for large scale wind turbines are generally heavy and huge in sizes, which translate into a hike in upfront and maintenance costs. Design optimizations are crucial in wind turbine generator. Multi-objective optimization is a general approach to the design of the generator because there are always tradeoffs in considerations. In many studies, optimizations are applied on mathematical models and the results are verified by means such as Finite Element Method (FEM). This review paper captures the fact that recent advancements in design optimization of Permanent Magnet Synchronous Generator (PMSG) for wind turbine systems are able to deliver tangible benefits to the renewable energy technology (RET) industry as a whole. Different design approaches, objectives applied in optimization, key variables, and optimization algorithms across different research are also presented in this paper.

Tackling water scarcity is a pressing challenge, propelling recent advancements in solar steam generation (SSG). Recently, 3D photoabsorbers have outperformed their 2D counterparts in recovering light and minimizing heat losses, enabling a surge in exploring 3D materials and designs. Herein, 3D structures are fabricated using polydopamine (PDA) functionalized carbonized palm fibers (PDA c‐fiber) to shed light on the degree of improvement in SSG efficiency compared to their 2D counterpart. Specifically, two 3D models, a cone, and a cylindrical cup, are chosen for their inherent features, including a hollow cavity, circular base, and curved surface. These architectural elements play a crucial role in trapping light, facilitating reflections, and efficiently converting solar energy to heat through the photothermal effect. Scaling palm fibers from 2D to 3D significantly boosts SSG efficiency, from 67.9% to 103.7%, with water evaporation rate enhanced from 1.171 kg m−2 h−1 to 1.869 kg m−2 h−1. Substantially, the 3D cup demonstrates superior photothermal performance primarily attributed to its heat recovery feature of the cup wall structure and circular basal area, enabling prolonged light‐to‐heat conversion. These findings provide valuable insights and foundation for developing efficient solar‐driven 3D upcycled photoabsorbers in the future. [ABSTRACT FROM AUTHOR]

The coupling of photoredox reactions utilizing both photogenerated electrons and holes has garnered significant attention for producing high-energy-density fuels and value-added products at the same time. In this work, all-in-one porous ultrathin ZnIn2S4 nanosheets were developed via a facile one-pot solvothermal method by carefully tuning the concentration of trisodium citrate in the synthesis medium. With the appropriate amount of trisodium citrate, the morphology structure of ZnIn2S4 can be modulated into 4–6 nm ultrathin layered sheets with noticeable nanopores of 10–70 nm, which exposes more active sites for the redox activity. The resultant cocatalyst-free ZnIn2S4 system was successfully employed in the photocatalytic H2 evolution coupled with benzyl alcohol oxidation to produce H2 fuel and benzaldehyde in the absence of sacrificial agents. The porous ZnIn2S4 nanosheets with ameliorated light absorption and enhanced redox capability achieved an optimal hydrogen yield of 22.2 mmol g−1 under 4 h simulated sunlight irradiation (AM 1.5), double that of its pristine form, resulting in an apparent quantum efficiency (AQE) value of 5.41% at 380 nm and a solar-to-hydrogen (STH) value of 0.204%. Interestingly, a highly selective (96%) benzaldehyde production of 0.33 mmol h−1 was observed concurrently with simultaneous benzyl alcohol conversion. In situ electron paramagnetic resonance (EPR) reveals that the high-selectivity benzaldehyde formation is attributed to the carbon-centered (Cα) radical-induced pathway with the direct involvement of the photogenerated holes in the C–H bond activation. Overall, this study highlights the importance of the morphology–activity relationship, providing valuable insights for the development of superior all-in-one ultrathin photocatalysts toward ameliorated dual-redox photocatalytic reactions. [ABSTRACT FROM AUTHOR]

Two-dimensional carbon nanowall (2D-CNW) structures were prepared by hot wire assisted plasma enhanced chemical vapor deposition (hw-PECVD) system on silicon substrates. Controlled variations in the film structure were observed with increase in applied rf power during deposition which has been established to increase the rate of dissociation of precursor gases. The structural changes resulted in the formation of wavy-like features on the 2D-CNW, thus further enhancing the surface area of the nanostructures. The FESEM results confirmed the morphology transformation and conclusively showed the evolution of the 2D-CNW novel structures while Raman results revealed increase in ID/IG ratio indicating increase in the presence of disordered domains due to the presence of open edges on the 2D-CNW structures. Subsequently, the best 2D-CNW based on the morphology and structural properties was functionalized with tin oxide (SnO2) nanoparticles and used as a working electrode in a photoelectrochemical (PEC) measurement system. Intriguingly, the SnO2 functionalized 2D-CNW showed enhancement in both Mott-Schottky profiles and LSV properties which suggested that these hierarchical networks showed promising potential application as effective charge-trapping medium in PEC systems. [ABSTRACT FROM AUTHOR]

Plasmonic effects in wide-bandgap photocatalysts loaded with noble metal nanoparticles (NPs) have been shown to enhance visible light absorption as well as charge transfer. TiO 2 owing to its superior photostability, abundance and non-toxcitiy, especially in form of nanotube arrays (NTAs) to maximize surface interactions, has been often used as a photoactive template. However systematic studies of photoelectrochemical properties in plasmonic TiO 2 NTAs are rare and usually involve Au NPs only. Here, we examine the effect of Ag NP loading of TiO 2 NTAs via photoreduction of different concenrations of AgNO 3 (20 mM–1100 mM) in order to establish the optimum value at which photoactivity is maximal. Remarkably, the system prepared from 200 mM aqueous solution were found to exhibit an unprecedented 680-fold increase in photocurrent density as compared to the bare anatase NTAs (0.041 mA·cm − 2 versus 0.06 μA·cm − 2 ). Furthermore, hydrogen evolution under AM 1.5G illumination was improved by 350% from 40 μL·cm − 2 in pristine anatase NTAs to 180 μL·cm − 2 in optimally decorated NTAs. [ABSTRACT FROM AUTHOR]