Thermal performance of a nanofluid assisted spectral beam-splitting Photovoltaic/Thermal (SBS-PV/T) system is contingent upon the thermo-optical characteristics of beam splitting fluids. However, real-time prediction of thermal and electric performance of such SBS-PV/T systems under outdoor testing with flow conditions is still underexplored. The present study focuses on real-time thermal performance of a CuO nanofluids based SBS-PV/T system for its energetic, economic and environmental perspective during autumn season in India. CuO nano-particles of sizes similar to 25-55 nm were used to prepare nanofluids and further optical and morphological characterised using UV-VIS-NIR spectrophotometer and Field Emission-Scanning Electron Microscopy (FE-SEM) methods, respectively. The outdoor experiments were conducted to analyse the effect of CuO-NPs loading and mass flow rates on electrical and thermal performance parameters of SBS-PV/T system. A maximum temperature gain with CuO nanofluids was observed approximate to 10.5 degrees C at 0.020 kg. s(-1), which is approximate to 4.8 % higher than DI water. Further, CuO nanofluids reduced the average surface temperature of PV cell by 5.67 degrees C over standalone PV system. In tested SBS-PV/T system, an average electrical efficiency dropped from 9.97 % to 9.52 % with CuO nanofluids against 11 % of stand-alone PV system. The tested SBS-PV/T system achieved the highest overall thermal efficiency approximate to 38.40 % with CuO nanofluids at an optimum mass flow rate of 0.035 kg. s(-1). Further, the economic analysis predicted a unit energy cost of about 3.39 INR/kWh for full-scale SBS-PV/T system, whereas, a stand-alone PV system cost about 4.26 INR/kWh.

This paper presents a performance comparison of monocrystalline silicon photovoltaic (PV) modules in monofacial and bifacial configurations, investigated under the tropical climatic conditions of IIT Bhilai, Chhattisgarh (21.2471 degrees N, 81.3189 degrees E). The study was conducted during the summer-monsoon period from May 2025 to August 2025. Utilizing real-time Global Horizontal Irradiance (GHI) and Plane-of-Array (POA) irradiance data captured by pyranometers mounted on a rooftop at the site, this work analyzes the observed effect of reflected irradiance on the Performance Ratio (PR) of the bifacial module. The PR was considered the key figure of merit, with attention given to the influence of solar irradiance, ambient temperature, and module temperature on PV performance. The results demonstrate a quantifiable enhancement in the PR for the bifacial module, directly attributable to the additional energy yield from its rear side. By providing empirical evidence from direct field measurements, this study highlights the tangible benefits of bifacial technology for Central India and offers valuable insights for optimizing PV system design in regions with pronounced seasonal variations.

The easiest way to analyze the performance of a PV module/array is by examining its current-voltage (I-V) curve. It is a laborious operation to record the I-V data of a single PV module all day. Furthermore, measuring several PV modules one after the other throughout the day becomes difficult and timeconsuming when done by hand. To overcome this difficulty, we have designed an Automatic Channel Selector (ACS) system that automatically records the I-V curves of multiple PV modules in sequence, with a two-minute time interval between readings. The prototype is designed to record the I-V curves of ten PV modules, but this design is not limited to. The ACS system prototype hardware consists of power relays, an Arduino UNO board, voltage regulators, and LED indicators. The recording of the data starts after three seconds of switching ON the power supply of the device and activating relay-1 for 178 seconds. After a two-second gap, relay 2 starts working for the same duration, and the process continues automatically until the last relay is activated. This ACS system is a low-cost, scalable, and efficient solution for recording I-V curves of PV modules in outdoor/research laboratories. It also greatly eliminates human intervention and measurement time.

Perovskite optoelectronic devices require characterization under chopped light illumination to accurately evaluate their performance metrics, including external quantum efficiency (EQE), responsivity (R), and detectivity (D*). We demonstrate that these parameters exhibit strong dependence on the chopping frequency, necessitating frequency optimization for reliable device performance assessment and operation. Through systematic characterization across a broad frequency range, we observe a capacitive-like response in the perovskite layer, which governs the frequency-dependent behavior of EQE and R. We propose a mathematical model to fit this response, enabling predictive performance analysis and explain the underlying physics by examining the impedance data. This work provides critical insights into frequency-resolved characterization protocols for perovskite optoelectronic devices, offering a framework to standardize performance evaluation and guide its optimization in presence of device limitations.

This paper presents a high-efficiency photovoltaic (PV)-driven water pumping system that combines a sensorless maximum power point tracking (MPPT) algorithm with a three-level T-type inverter. The proposed MPPT eliminates the need for current sensors by employing a Luenberger observer for current estimation, thereby reducing hardware cost and improving system reliability. The T-type inverter enhances power quality and overall system efficiency by lowering switching losses and total harmonic distortion (THD). The complete PV-boost-inverter-motor configuration is modeled and simulated in MATLAB/Simulink. Simulation results demonstrate stable operation, effective DC-link voltage regulation, and improved output waveform quality under variable solar irradiance. The proposed system offers a simple, cost-effective, and reliable solution for sustainable solar water pumping applications in rural and off-grid areas.

Abstract Due to varying weather conditions, the analysis of accuracy and the performance prediction of photovoltaic (PV) modules using different electrical models are necessary from location to location. This paper presents and analyses the performance of monocrystalline and polycrystalline Si solar PV modules installed in outdoor operating conditions in Raipur, Chhattisgarh, India. In this research article the energy generation of Si (both mono and poly) PV module for which best fit for single diode or double diode electrical models at our locations. The monthly experimental results are compared with different methods of single diode (four and five parameters) and double diode (seven parameters) mathematical model. The monthly average performance ratio, efficiency, and output energy were calculated and compared on year data. The correlation coefficient ( C R ), mean bias error ( E MB ), and root mean square error ( E RMS ) were among the statistical measures used to analyze the results. Throughout the monsoon, cold, and hot seasons, the monthly accuracy of mathematical models was examined. The seven-parameter double diode model follows the experimental results as compared with the other models with an average relative error of 5.78% throughout the year for the monocrystalline (375 Wp) PV module. The four-parameter single-diode model is the best match with the experimental results for the polycrystalline (330 Wp) PV module throughout the year, with an average relative error of 5.35%, but in the summer season, due to higher temperature series resistance and the recombination losses increases, as a result the five parameters double diode model is the best-performing model with an average relative error of 3.67%.

Abstract Perovskite-based photodetectors have recently attracted widespread attention due to their excellent optoelectronic characteristics; however, their broader implementation remains hindered by limited long-term stability. In the present work, a solution-processed route is employed to fabricate a stable n–i–p architecture CsMAFAPb(IBr)3-based self-powered photodetector (SPPD). The optimized device achieved a responsivity of 0.2539A W–1 at 700 nm along with a specific detectivity of 3.002 × 1011 Jones at the same wavelength. In addition, the device delivered a maximum external quantum efficiency (EQE) of nearly 60%, a broad linear dynamic range of 82 dB, and an on–off ratio of 1.35 × 104 under zero-bias operation. The fabricated photodetector also demonstrated promising operational stability, exhibiting an average decrease of approximately 50% in responsivity, EQE, and detectivity after 94 days (∼2256 h) under ambient conditions, which may be attributed to improved crystallinity and grain uniformity of the active perovskite layer. The reduced recombination losses are inferred from the observed optical and structural characteristics. Moreover, the photocurrent versus time (I–t) characteristics monitored over the same duration revealed nearly 60% degradation after 94 days.

Deploying vertical bifacial PV modules can play a significant role in agrivoltaics, fencing walls, noise barriers, building integrated photovoltaics (BIPV), solar PV for electric vehicles, and many other applications. This research work presents the energy yield measurement and simulation of vertical bifacial photovoltaic (VBPV) modules facing East–West (E-W) and South-North (S–N) directions. Also, the VBPV modules are compared with vertical and tilted south-facing monofacial PV modules installed on the rooftop of IIT Bhilai academic building, Raipur (21.16° N, 81.65° E), India. From a series of experiments, 19 days of data were collected over the one-year period from May 2022 to April 2023, with specific inclusion of important days like solstices and equinoxes. The results show that the E-W facing VBPV module gives two production peaks, one in the morning and another in the evening, as compared to the single notable rise at midday observed for a monofacial module. It has been observed that energy generation by E-W facing VBPV module is 0.91 times of S–N facing VBPV, and 1.02 times more than south-facing vertical monofacial module during the studied time frame of 07:15 AM—04:45 PM. This study also presents the generation profiles of E–W and S–N VBPV modules, and compares them with monofacial PV modules for an experimental site located in the central-eastern region of India. Measured energy generation results are compared with PVsyst simulations, while also addressing the limitations of the PVsyst simulation of vertical PV modules.

This study presents the fabrication and characterization of self-powered (0 V bias) perovskite photodetectors with a fast response time. We fabricated a RbCsMAFAPb(IBr)$_{3}$ perovskite photodetector in an n-i-p planar architecture and systematically analyzed its performance. The device achieves an external quantum efficiency (EQE) exceeding 55% and a peak responsivity of 0.306 A/W at 730 nm. At the same wavelength, it demonstrates a detectivity of $2.36 \times 10^{11}$ Jones. With a rise time of 0.286ms, the detector exhibits a competitive response speed among perovskite photodetectors. The device exhibited good stability over the course of 10 days. Furthermore, we investigated the incorporation of Al $_{2}$ O$_{3}$ nanoparticles in the electron transport layer (ETL) and their impact on the morphology of the perovskite film.

Recent advances in perovskite optoelectronics highlight their exceptional potential for photodetection applications, leveraging their outstanding light-harvesting capabilities and solution-processability. In this work, we demonstrate a self-powered perovskite photodetector featuring an optimized p-i-n architecture, utilizing RbCsMAFAPb(IBr)3 as the photoactive layer with 4PACz and C60 as hole and electron transport layers, respectively. The devices exhibit remarkable performance metrics, including a peak external quantum efficiency (EQE) of ∼ 73 × 10 ^11 Jones across the 690–780 nm spectral range. With a high-speed response characterized by a time constant of 79.57 s and an operational bandwidth exceeding 2 kHz, the photodetector shows excellent suitability for high-speed applications. The entirely solution-processed fabrication approach combined with self-powered operation presents a promising pathway toward scalable, energy-efficient optoelectronic devices.

In hybrid photovoltaic (PV)/thermal system, to achieve high thermal performance, liquid absorbers based spectral splitting method has been reported recently. The current level of technology for such novel hybrid systems is limited to either theoretical work or laboratory scale prototype testing. Experimental studies that specifically focus on real-time monitoring of the performance characteristics of spectral splitting systems are necessary. We performed outdoor testing on a full-scale spectral splitting hybrid photovoltaic/thermal system under Indian climatic conditions. The performance of hybrid system was analysed considering different air gaps between PV panel and the thermal system, and with and without back cooling arrangement. The study utilised commonly used liquid filters such as ethylene glycol/water mixture (50-50 vol%), ethanol/water mixture (50-50 vol%), and de-ionized water considering their high transmittance in visible and strong absorption in infra-red regions of solar spectrum. The experimental results showed that the thermal system experienced a maximum temperature gain of 54.5 degrees C with back cooling arrangement. Furthermore, the PV panel in hybrid system showed a significant lower average surface temperature as compared to the bare photovoltaic panel at an air gap of 3 cm. The experimental study observed a maximum overall efficiency of 72.7 % with de-ionized water as spectral splitter with back cooling arrangement.The proposed hybrid system is able to decouple the temperature of the thermal system and PV processes so that the combined performance is enhanced.

In last two decades, a significant performance enhancement of nanofluid-based spectral beam splitting photovoltaic/thermal (SBS-PV/T) system has been reported. However, the studies reported so far, related to nanofluids (as spectral beam splitter) in SBS-PV/T systems, is limited to either laboratory scale experimental testing or simulation work. Further, a handful studies are available in literature to evaluate the thermal performance of these hybrid systems with full-scale prototype over several days of outdoor experiments. Considering that, the present study analyzed real-time performance characteristics of a full-scale nanofluid laden SBS-PV/T system under outdoor condition in tropical climate of India. The study utilised chemically synthesized gold nanoparticles (Au-NPs) of sizes similar to 20-25 nm, to prepare Au plasmonic nanofluids at different mass concentrations. Localized Surface Plasmon Resonance (LSPR) peak of Au-NPs appears at 523 nm, well within the visible region. The outdoor testing revealed a maximum temperature rise of about 66 degrees C in the nanofluid channel with Au plasmonic nanofluids at mass fraction of 0.0004 wt%, which is about 6 degrees C higher than DI water under similar operating conditions. Moreover, PV modules with Au plasmonic nanofluids experienced lower surface average temperature as compared to the standalone PV system (i.e., 54 degrees C against 62 degrees C). Further, overall thermal efficiency of SBS-PV/T system was about 7 % higher with Au plasmonic nanofluids at mass concentration of 0.0004 wt% over DI water. The study concludes that SBS-PV/T systems, particularly those employing real-time monitoring, hold significant promise for its commercialization.

India accounts for around $18 \%$ of global CO2 emissions from transportation. Transportation with conventional energy sources such as coal, oil, and natural gas is costly and poses environmental challenges. The Government of India promotes and subsidizes electric vehicles for fast adoption. The e-Rickshaw is an ideal option for short-distance travel in urban areas due to its low cost. However, one major challenge of e-Rickshaws is battery charging for long-distance travel. In this research article, a survey of e-Rickshaws is conducted in the capital of Chhattisgarh, with an e-Rickshaw powered by a flexible solar photovoltaic (PV) module ($\mathbf{4 2 5} \mathbf{~ W p}$) with a maximum power point tracking (MPPT) charge controller, properly designed, installed, and commissioned on the roof of the vehicle. A comparative analysis of a conventional e-Rickshaw and an e-Rickshaw integrated with a solar PV module is presented. The conventional e-Rickshaw consumes around 7-9 units of electricity per day to fully charge the batteries, resulting in an annual utility bill of approximately Rs. $15,330-19,710$ at a rate of Rs. 6.0 per unit. After integrating the PV module, the e-Rickshaw operator can save up to Rs. 5,475 per year. Additionally, the operator’s travel range and income increase by up to Rs. 7,200 per month. Solar PV integration on the e-Rickshaw mitigates about 0.56 tonnes of CO2 emissions per year per e-Rickshaw.

Organic-inorganic halide perovskites have shown significant compatibility with c-Si solar cells due to their high absorption coefficient and bandgap tunability. In this study, we have developed mixed-halide mixed-cation perovskite RbCsMAFAPb(IBr)3-based inverted solar cell (Glass/ITO/PTAA/Al2O3-NPs/RbCsMAFAPb(IBr)3/C60/ BCP) and utilized the experimental data to numerically model a monolithic perovskite/c-Si tandem solar cell architecture using SCAPS-1D framework. The top (Eg = 1.61 eV) and bottom (Eg = 1.12 eV) sub cells of the tandem structure are calibrated with their experimental counterparts to validate the simulation results. The bestfabricated perovskite solar cell (PSC) exhibits a JSC of 22.09 mA/cm2, VOC of 0.98 V, fill factor (FF) of 64.69% and power conversion efficiency (PCE) of 14.06%. Under 1-sun illumination, the optimized modelled standalone top cell exhibits a JSC of 21.23 mA/cm2, VOC of 1.01 V, FF of 69.37% and PCE of 14.94% at a RbCsMAFAPb(IBr)3layer thickness of 500 nm. The modelled bottom silicon heterojunction (SHJ) cell showed a JSC of 36.84 mA/cm2, VOC of 0.70 V, FF of 73.14% and, PCE of 19.11% at Si-layer thickness of 250 mu m. The optoelectronic properties of the fabricated top PSC have been investigated in this work. The loss mechanism related to interface and bulk defects, and series and shunt resistances of the top sub cell have also been studied. To simulate the tandem architecture, the ideal current matching approach has been considered here, where the top and bottom sub cells are connected by an ideal interconnected layer, with negligible optoelectronic losses. Under the current matching condition, the modelled RbCsMAFAPb(IBr)3-on-Si tandem cell exhibits a JSC of 17.91 mA/cm2, VOC of 1.73 V, FF of 77.77% and PCE of 23.85%. The in-depth analysis highlights a strong correlation between experimental study and theoretical predictions providing valuable insights for further advancements of monolithic tandem solar cells.

The Internet of Things (IoT)-enabled communication can potentially enhance rural development by providing accessible solutions for remote areas. Leveraging long-range, low-power, wide-area networks (LoRaWAN), IoT-based systems can streamline government schemes to benefit rural populations. Rural initiatives like the Mahatma Gandhi National Rural Employment Guarantee Act (MGNREGA) face challenges like delayed payments due to infrastructure limitations, including unreliable electricity and internet connectivity. This paper presents a solar-powered IoT prototype, "Shramik Bhugtaan Seva Kendra (SBSK)," designed to provide timely payments and attendance verification for MGNREGA beneficiaries. By incorporating LoRaWAN and QR-based authentication, the system ensures financial transparency and reduces fraud, thus supporting rural development.

Solar energy is a renewable energy source that is capable of meeting a large portion of the thermal and electrical energy required throughout the entire globe. In the past few years, there has been the subject of extensive research exploring a variety of spectral fluids that were used as beam splitters in photovoltaic/thermal systems referred to as de-coupled photovoltaic/thermal systems. The work reported here performed real-time experimentation and utilized Al2O3/Water nanofluid and de-ionized water as spectral fluids due to their tunable properties, making it an ambitious choice for beam-splitting applications. Furthermore, this work also considered the effect of the nanoparticle concentrations, i.e., 0.0004 wt.% and 0.0001 wt.% at a constant mass flow rate of 0.025 kg/s in the thermal receiver (spectral channel) of the novel photovoltaic/thermal system. Results of the present work showed that Al2O3/water nanofluid with 0.0004 wt.% gained a maximum temperature of 44 oC. However, the lower PV surface temperature in a hybrid PV/T system was found to be 56.5 oC against 60 oC (standalone PV system) utilizing 0.0004 wt.% of Al2O3 nanofluid as spectral fluid. The overall efficiency of work presented herein was found to be 40%, 37.5%, and 32%, utilizing 0.0004 wt.%, 0.0001 wt.%, and de-ionized water, respectively, at a constant mass flow rate of 0.025 kg/s.

Nanofluid-based spectral beam splitting photovoltaic/thermal systems (NSBS-PV/T) showed better thermal regulation of photovoltaic and thermal system in decoupled way. Recently, phase change materials are (PCM) used as spectral beam filters and proved to be a better alternative for overall thermal management of such NSBSPV/T systems. However, there is still a key research gap where NSBS-PV/T system considered the combined effect of nanofluids (as spectral beam filters) and PCM (as storage medium) for enhanced thermal performance of hybrid PV/T system experimentally. Therefore, we utilised Ag-Al2O3 nanoparticles-based hybrid nanofluid in NSBS-PV/T system and tested hybrid system with PCM (NSBS-PV/T+ PCM) under real-outdoor conditions for very first time. The tested systems were analysed considering different system configurations i.e., with and without PCM and varying the mass flow rates of spectral fluids in hybrid PV/T system. The experimental study results showed that average surface temperature of PV cell was reduced significantly with Ag-Al2O3 hybrid nanofluid at mass fraction of 4 mg/L. Further, PCM was effective to lower the surface temperature of PV cell (from back side) but the exposure time was a dominant factor for heat storage within the PCM. The overall thermal efficiency of NSBS-PV/T+ PCM was observed about 28.4% at an optimum mass flow rate of 0.035 kg/s. The study suggests that future studies should explore PCMs with better thermo-physical properties, optimisation of its geometric parameters (thermal storage unit) and sun exposure time to develop more efficient NSBS-PV/T systems for its future technological development.

This paper presents a sensorless intelligent maximum power point tracking (MPPT) strategy that combines neural network prediction with observer-based current estimation for photovoltaic (PV) systems using a DC-DC boost converter. Conventional MPPT methods often depend on current sensors, increasing system cost, noise, and complexity, while also showing poor dynamic performance under rapid irradiance changes. The proposed system eliminates current sensors by employing a Luenberger Observer to estimate the inductor current, which is then used by a trained feedforward neural network (NN) to determine the optimal duty cycle in real time. The neural network is trained using three months of experimental data from a bifacial PV installation to ensure accurate modeling across varying environmental conditions. Simulation results in MATLAB/Simulink demonstrate faster convergence, minimal steady-state oscillation, and 99.02 % tracking efficiency, outperforming conventional Perturb and Observe (P&O) and Particle Swarm Optimization (PSO) techniques. The proposed sensorless NN-observer MPPT approach offers a reliable and cost-effective solution for real-time PV energy harvesting and is suitable for embedded implementation on FPGA or Raspberry Pi platforms.

Dust accumulation on photovoltaic (PV) modules significantly impacts their efficiency and energy output, particularly in regions with high particulate deposition. This study investigates the performance degradation of monocrystalline Monofacial and bifacial PV panels due to natural dust accumulation over time. Experimental analysis was conducted at the Indian Institute of Technology Bhilai, where key electrical parameters such as power output and efficiency were monitored under clean and dusty conditions. Study indicates the losses observed in panels. This study helped determine and understand dusting patterns, with consistent decrease in power throughout experimental period. Additionally, adverse weather conditions caused significant performance fluctuations. The study highlights the necessity of optimized cleaning schedules, with monocrystalline panels requiring more frequent maintenance than bifacial panels. These findings provide valuable insights into dust mitigation strategies and system optimization for PV installations in dust-prone environments.