Nanotechnology is emerging with the biosynthesis of silver nanoparticles which is toxic free and friendly with the environment. Out of all the biosynthesis methods, plant extracts are more predominantly used which is readily available, and it is a least cost method. The plants have secondary metabolites such as phenolic compounds named as flavonoids; tannins are turned to be the reluctant to synthesize silver nanoparticles (AgNPs) from silver nitrate. The plant chosen to synthesize silver nanoparticles is the Hibiscus rosasinensis for the reason of the presence of various biomolecules. The reduction and stabilization process are performed due to the biomolecules. Silver nanoparticles produced from the Hibiscus plant are easier than the conventional method. The formation of nanoparticle of silver is indicated by the maximum absorbance peak at a wavelength of 458 nm obtained from the leaf and the bark extracts. The antimicrobicidal effects on various microbes were examined, and it is proved that bark produced better results.

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Remote area electrification is a crucial need in sub-Saharan Africa’s drive to attain universal electrification. In Sierra Leone, with a rural population of over 5 million, the electrification rate accounts for less than 10% of the total inhabitants. This paper presents a comparative techno-economic analysis carried out to determine the most feasible of four individual options for off-grid mini-grid power generation system utilizing sources that include: Solar Photo Voltaic (SPV), Diesel Generator (DG), and Battery Storage (BS) system, to provide electricity for a rural and remote village located in the northwestern part of Sierra Leone (longitude 9.1°W and latitude 12.6°N), with an average daily solar irradiance between 4.6 and 6 kWh/m2/day. An assessment of the total electrical load estimated an expected daily consumption of 178 kWh. Simulation, optimization, and sensitivity analyses of each one of the individual power generation systems were carried out using HOMER software. Economic parameters such as Cost of Capital (CC), Net Present Cost (NPC), Levelized Cost of Electricity (LCOE)), technical parameters (energy production characteristics), and greenhouse gases emissions were compared and analyzed. Key findings from the simulation result indicate that systems consisting of DG only ($29,750) and SPV/BS ($110,131) obtained the least and highest CC, respectively. Similarly, in a respective manner, the highest and least NPC were obtained for systems with DG only ($496,336) and PV/DG/BS ($152,491) over a 25-year project lifetime. Furthermore, the least LCOE was obtained for the system comprising PV/DG/BS ($0.336/kWh). With an expected annual generation of (75,121 kWh), PV/DG/BS was obtained to be the most optimal solution. The sensitivity analysis observed that a reduction in the discount rate consequently reduces the LCOE of such a system. Furthermore, the model accounts for a 90% renewable energy fraction, with a significant reduction in the amount of annual GHG emissions, when compared with a generation system using diesel generator only.

Photovoltaic power generation is a potential alternative energy source that offers several benefits over other alternative energy sources such as wind, sun, ocean, biomass, geothermal, and so on. Multilevel inverters are essential for power conversion in solar power generation. These multilevel inverters employ three distinct topologies: diode-clamped (neutral-point clamped) inverter, capacitor-clamped (flying capacitor) inverter, and cascaded H-bridge multilevel inverter. The cascaded H-bridge multilevel inverter is more appropriate for photovoltaic applications than the other two topologies. The proposed system asymmetrical cascaded multilevel inverter (ACMLI) is energized using a photovoltaic system (PV). A three-phase cascaded H-bridge fifteen-level inverter for grid-connected solar systems is given in this study utilizing a proportional integral controller. The harmonic distortion was removed using a multicarrier pulse width modulation method. The MATLAB/Simulink is used to simulate the performance of a three-phase cascaded H-bridge fifteen-level inverter in terms of harmonic content and number of switches. To test the performance of the designed system, a hardware prototype was created. From the obtained results, the proposed method reduces the switch count, harmonic distortion, and rejects the external disturbances of input and output variables.

Electrical power systems are accessible in renewable energy systems, and hybrid battery systems or energy storage systems (ESS) are capable of delivering uninterruptible power to the demand even if faults occur. Additionally, the energy storage device increases system dynamics during power fluctuations. A photovoltaic (PV) battery hybrid system with an ESS link is considered, and an impact leveling management system is planned to transfer the ability to load as well as the battery. Electricity generation is vital, and also the method is fairly complicated. The goal of lowering production prices, maintaining instrumentation, and its fuels, all play necessary roles within the method. As a result, producers should import fuel to satisfy the electrical demand, the assembly value rises. We are considering using renewable energy sources to avert a harmful economic imbalance. We tend to introduce a replacement system to complete the load of alternative energy. To boost inertia and improve frequency responsiveness, load side inverters linking PV to grid and energy storage systems are used on a utility-scale (ESS). Furthermore, with growing PV penetration, independent development of PV and ESS linking to the load and the battery is one of the alternatives for steady operation of the standalone system. The associate integrated the idea for PV and ESS integration to AC load and ESS and it is used for automotive applications.