Along with the increasing adoption of renewable energy sources, maintaining grid continuity has become a growing concern. As solar photovoltaic (PV) systems and battery storage systems (BESS) proliferate, their contribution toward increasing system resilience and offering frequency response is becoming critical. This research focuses on frequency regulation and assesses how BESS increases stability by modifying the droop coefficient in primary frequency control. We present a simulation-based analysis for different droop settings and construct a BESS sizing algorithm to mitigate a 0.5 Hz frequency dip and advocate a partial load-shedding approach with BESS aid. In addition, the integration of PV systems contributed to a significant reduction in the required size of the BESS, as the PV systems were able to directly supply a portion of the energy demand. The findings demonstrate that adaptive droop improves frequency response, optimal BESS size enhances energy efficiency, and load-shedding with BESS support reduces the burden of excessive load shedding to increase reliability and balance in the system.

Electrochromic nanoparticle on mirror (eNPoM) facilitates voltage-controlled color changes through the adjustment of optical resonances at nanoscale. This study focused on designing eNPOMs integrating plasmonic cores made of Au, AZO, GZO, and ITO with an electrochromic shell made of PANI for three different configurations: cylindrical coreshell, cylindrical core-shell structure with hollow center, and pyramidal core-shell designs. We utilized finite-difference timedomain (FDTD) solver to investigate the scattering cross section and electric field distributions in oxidized, semi-oxidized, and reduced states. Moreover, chromaticity coordinates for different redox states were quantified through the CIE 1931 diagram and color differences were numerically assessed according to the CIEDE2000 standard. Remarkably, the structures comprised of GZO and Au showed CIEDE2000 color differences exceeding 50, whereas the ITO-based configuration demonstrated >56 chromatic contrast with distinct plasmonic resonances. The electric field distribution observed in this study indicated strong field confinement in oxidized states. Electron delocalization was through reduction, aligned with our calculated spectral trends. Moreover, a comparative analysis of the calculated results with WO3based eNPoM was performed. However, PANI-based systems demonstrated relatively higher color contrast and modulation depth. Our findings will significantly enhance the development of tunable eNPOM platforms such as high-resolution nano-displays, adaptive optics, and responsive metasurfaces.

The emitter is an indispensable part of a thermophotovoltaic (TPV) energy conversion system. However, conventional metal-dielectric emitters suffer greatly from the oxidation of metal layers at high temperatures. Emitters based on all-oxide structures can be a possible solution to this problem. Here, we present a polarization and incident angle-insensitive multilayer emitter structure based on$\text{MgO} / \text{ITO}$composite layers for a conventional TPV system operating at 1450 to 1500 K temperature. The emission mechanism of the proposed structure was assessed using the finite-difference time-domain (FDTD) method, and the structural dimensions were optimized using a brute-force design approach. The optical simulation of the optimized structure provides a peak emission of around 98.8% at the wavelength of 1928 nm, which coincides perfectly with the spectral response of the$\text{In}_{0.74} \text{Ga}_{0.26}$As cell and the blackbody radiation of the 1450 to 1500 K heat sources. Moreover, our designed structure was polarization-independent and insensitive to the incident angle of radiation up to 70° for both TM and TE polarized light. This study will have an immense impact on high-temperature applications, such as thermophotovoltaic systems, photodetectors, and sensors.

Graphene-based plasmonic tweezers achieve strong localized field confinement by taking advantage of their low-loss properties and unique tunable conductivity. To improve near-field localization and optical trapping performance, we designed an optical nanotweezer structure in the shape of a bow-tie with a gap at the center. Using extensive parametric analysis, we explored structural dimensions, including gap size, length and width, impact electric field, trapping performance, and localized surface plasmon resonance. Our findings demonstrated that while width primarily affected near-field strength, increasing length caused a redshift in the resonant frequency. We obtained a peak optical force of$-1.57 \text{nN}/\mathrm{W}_{\mu \mathrm{m}^{-2}}$at 7.3 THz frequency on a nanoparticle by introducing an 8 nm gap between the two bow-tie triangles, which is twofold higher than that of the gapless bow-tie structure. A deep optical potential well ($>-8 \times 10^{3} \text{kb}_{\mathrm{B}} \mathrm{T}/\mathrm{W}_{\mu \mathrm{m}^{-2}}$) was revealed close to the surface. The field and potential variation along the vertical axis further confirmed stable trapping. These findings highlight the potential of graphene plasmonic tweezers for high-precision dielectric and biological nanoparticle manipulation in lab-on-a-chip applications by demonstrating their strong geometrical tunability.

We proposed an extremely sensitive E. Coli sensor based on a hyperbolic metamaterial structure combining ultra-thin Ag-Al2O3 layers to minimize metallic optical loss. The principle relied on detecting the change in the resonance wavelength due to the interaction of bacteria with the surrounding aqueous environment by utilizing the finite-difference time-domain numerical technique. Our proposed hyperbolic metamaterial E. Coli sensor operated in the range from visible to near-infrared wavelengths exhibiting strong bulk plasmon polaritons at the hyperbolic regime$(\lambda\geq 460\ \text{nm})$. An anisotropic hyperbolic range was obtained theoretically by solving the effective medium theory. An outstanding sensitivity of 9000 nm per bacteria was achieved for a bulk plasmon-polariton mode. The hyperbolic metamaterial was the origin of obtaining such extremely high sensitivity; no bulk plasmon polaritons were found without hyperbolic metamaterial. We analyzed the effect of different shapes in two-dimensional Ag differential grating on sensing performance. Additionally, we compared the performance parameters of our proposed E. Coli sensor with recently demonstrated sensors. Our proposed hyperbolic metamaterial structure has the potential as a highly sensitive E. Coli sensor operating in a wide range of wavelengths for label-free detection.

Study of highly effective dopants of carbon nanotube is essential to understand the mechanism and produce ultrahigh conductive materials for high-power or high-current electrical applications. Though there are several experimental reports of chemically doped high electrical conductivity carbon nanotubes, influence of doping on quantum conduction is not studied well. Here, we investigated the impact of dopant such as$I_{2}$and$AuCl_{3}$on the electronic structure and quantum conduction using ab initio theoretical calculations. For both$I_{2}$and$AuCl_{3}$, they are adsorbed in carbon nanotube molecules and act as p-type dopants. Our study reveals that −1.61 eV shift in Fermi level occurs for$AuCl_{3}$doping in CNT, which implies possibility of ultrahigh conductivity. Furthermore, transmission function calculations confirm significant increase of available quantum channels for conduction in$AuCl_{3}$doped CNT.