Solar Architecture Research Articles

Efficient indoor p-i-n hybrid perovskite solar cells using low temperature solution processed NiO as hole extraction layers

Hybrid perovskites have received tremendous attention due to their exceptional photovoltaic and optoelectronic properties. Among the two widely used perovskite solar cell device architectures of n-i-p and p-i-n, the latter is interesting in terms of its simplicity of fabrication and lower energy input. However this structure mostly uses PEDOT:PSS as a hole transporting layer which can accelerate the perovskite solar cell degradation. Hence the development of stable, inorganic hole extraction layers (HEL), without compromising the simplicity of device fabrication is crucial in this fast-growing photovoltaic field. Here we demonstrate a low temperature (~100 °C) solution - processed and ultrathin (~6 nm) NiO nanoparticle thin films as an efficient HEL for CH3NH3PbI3 based perovskite solar cells. We measure a power conversion efficiency (PCE) of 13.3% on rigid glass substrates and 8.5% on flexible substrates. A comparison with PEDOT:PSS based MAPbI3 solar cells (PCE ~ 7.9%) shows that NiO based solar cells have higher short circuit current density and improved open circuit voltage (1.03 V). Apart from the photovoltaic performance under 1 Sun, the efficient hole extraction property of NiO is demonstrated for indoor lighting as well with a PCE of 23.0% for NiO based CH3NH3PbI2.9Cl0.1p-i-n solar cells under compact fluorescent lighting. Compared to the perovskite solar cells fabricated on PEDOT:PSS HEL, better shelf-life stability is observed for perovskite solar cells fabricated on NiO HEL. Detailed microstructural and photophysical investigations imply uniform morphology, lower recombination losses, and improved charge transfer properties for CH3NH3PbI3 grown on NiO HEL.

A Reconfigurable Solar Photovoltaic Grid-Tied Inverter Architecture for Enhanced Energy Access in Backup Power Applications

In this paper, a photovoltaic (PV) reconfigurable grid-tied inverter (RGTI) scheme is proposed. Unlike a conventional GTI that ceases operation during a power outage, the RGTI is designed to act as a regular GTI in the on-grid mode but it is reconfigured to function as a DC-DC charge-controller that continues operation during a grid outage. During this period, the RGTI is tied to the battery-bank of an external UPS based backup power system to augment it with solar power. Such an operation in off-grid mode without employing communication with the UPS is challenging, as the control of RGTI must not conflict with the battery management system of the UPS. The hardware and control design aspects of this requirement are discussed in this paper. A battery emulation control scheme is proposed for the RGTI that facilitates seamless functioning of the RGTI in parallel with the physical UPS battery to reduce its discharge current. A system-level control scheme for overall operation and power management is presented to handle the dynamic variations in solar irradiation and UPS loads during the day, such that the battery discharge burden is minimized. The design and operation of the proposed RGTI system are independent of the external UPS and can be integrated with an UPS supplied by any manufacturer. Experimental results on a 4~kVA hardware setup validate the proposed RGTI concept, its operation and control.

Optimization of a BIPV system to mitigate greenhouse gas and indoor environment

The solar architecture is defined as a kind of building integrated photovoltaic (BIPV) which the Photovoltaic (PV) modules are deployed to passive solar concepts, to minimize the heating & cooling load, to upgrade the indoor environmental quality and to be adjustable for regional weather and to continuously succeed architectural culture and history. The most ideal form of a BIPV is a multi-functional and ecological convergence through a passive concept application of a photovoltaic module for a building. The solar architecture needs to consider the architectural culture and history of the region through an ecological convergence which is applicable to a passive concept if the environment, energy and comfort problems will be effectively mitigated. The evaluation standard is needed to fulfill these requirements of solar architecture. The renewable energy sources are getting very hot issues, due to the environmental pollution, global warming, and energy shortage, etc. It is reasonable to disseminate the representative energy systems which could be ecologically convergent with the regional architecture. Most renewable energy systems including PV could not be activate or not be environmentally friendly if the systems are planned simply without multi-functional and ecological convergence. This paper describes the ecological criteria to optimize solar architecture through an ecological convergence of a passive solar architecture and photovoltaic system.

Chemisorption of Atomically Precise 42-Carbon Graphene Quantum Dots on Metal Oxide Films Greatly Accelerates Interfacial Electron Transfer.

Graphene quantum dots (GQDs) are emerging as environmentally friendly, low-cost, and highly tunable building blocks in solar energy conversion architectures, such as solar (fuel) cells. Specifically, GQDs constitute a promising alternative for organometallic dyes in sensitized oxide systems. Current sensitized solar cells employing atomically precise GQDs are based on physisorbed sensitizers, with typically limited efficiencies. Chemisorption has been pointed out as a solution to boost photoconversion efficiencies, by allowing improved control over sensitizer surface coverage and sensitizer-oxide coupling strength. Here, employing time-resolved THz spectroscopy, we demonstrate that chemisorption of atomically precise C42-GQDs (hexa-peri-hexabenzocoronene derivatives consisting of 42 sp2 carbon atoms) onto mesoporous metal oxides, enabled by their functionalization with a carboxylate group, enhances electron transfer (ET) rates by almost 2 orders of magnitude when compared with physisorbed sensitizers. Density functional theory (DFT) calculations, absorption spectroscopy and valence band X-ray photoelectron spectroscopy reveal that the enhanced ET rates can be traced to stronger donor–acceptor coupling strength enabled by chemisorption.

Capillary-Flow-Optimized Heat Localization Induced by an Air-Enclosed Three-Dimensional Hierarchical Network for Elevated Solar Evaporation.

Solar evaporation is a cost-effective way for obtaining clean water using renewable energy. However, many solar evaporation devices still show unsatisfactory performance and suffer from inefficient utilization of absorbed solar energy. Herein, numerical simulations of solar evaporation demonstrate that the heat management is a key factor governing the solar evaporation efficiency. This prediction is confirmed through using a bilayered solar steam generation architecture [hollow glass microsphere-carbon black (HS-CB)] both in laboratory- and pilot-scale studies. The HS-CB consists of a CB film as a solar-thermal conversion layer and three-dimensional hierarchical polyvinylidene fluoride skeleton cross-linking HSs as a heat localization and water-transporting layer. A balance between thermal insulation and capillary-driven water transport can be reached by tuning the porosity of the thermal-insulating layer, thus inducing optimized heat localization. The proposed structure evaporates water with an efficiency of 82.1% under 1 sun irradiance (1 kW m-2) in the laboratory and can even stably produce 4.63 L m-2 d-1 (average efficiency of 37%) of purified water from highly concentrated industrial waste water in the pilot study, demonstrating its promising potential for applications in seawater desalination and brackish water purification.

Design validation and analysis of the drive range enhancement and battery bank deration in electric vehicle integrated with split power solar source

Solar panels are prominently incorporated into electric vehicle rooftop to charge the battery bank. In this paper, the analytical design of two solar electric vehicle models powered with split power solar source architecture and conventional solar power source architecture are presented. The operational behavior of the analytically designed solar electric vehicle models is validated using Matlab. The superiority between split power solar source and conventional solar power source in terms of power contribution capability to the electric vehicle battery bank is analysed under real-time conditions using PVsyst real-time simulator. Further, the drive range enhancement and battery bank deration rate in the two solar EV models due to the incorporation of solar power source is analysed and compared for real-time conditions. Finally, the results of the superior solar electric vehicle model are validated through experimental construction and testing of the model. The comparative study concludes that solar electric vehicle model powered with split power solar source architecture is the best in terms of maintaining battery performance, power contribution capability and drive range enhancement.

New trends in solar: A comparative study assessing the attitudes towards the adoption of rooftop PV

The factors affecting the adoption of conventional solar PV have been broadly addressed in the recent literature. However, it is still to determine the public's acceptance of innovations of the traditional solar PV architecture. Building applied photovoltaic technology (BAPV) is a technological innovation that can be installed over existing building surfaces. This study compares an evaluation of the conscious and subconscious attitudinal, control and normative beliefs of American homeowners when randomly primed with two brochures depicting the purchasing, installation, and commissioning of solar PV systems, developed according to the characteristics of conventional and an adhesive “plug and play” BAPV system. The survey instrument (N = 400 survey participants) was designed in consonance to the Theory of Planned Behavior (TPB).When comparing the direct measures for each solar PV technology, no significant differences were found. This may indicate that for those unfamiliar with PV technology, placing an adhesive backing module on the roof is standard procedure and does not impact purchasing intentions. The evaluation further showed that unlike the subconscious control beliefs, social norms and attitudes have a significant impact on forming intentions to adopt solar PV. The implications of these findings for strategy, policy and future research are explored.

Quantum-cutting Yb3+-doped perovskite nanocrystals for monolithic bilayer luminescent solar concentrators

Quantum-cutting Yb3+:CsPb(Cl1−xBrx)3 nanocrystals mitigate thermalization and reabsorption losses in a new monolithic bilayer luminescent solar concentrator device architecture.

Energy yield of all thin‐film perovskite/CIGS tandem solar modules

AbstractPerovskite/CuIn1 − xGaxSe2 (CIGS) tandem photovoltaics (PV) promises high power conversion efficiencies in combination with the advantages of a light weight and an all thin‐film PV technology. However, the complexity of perovskite/CIGS tandem solar module architectures requires careful optimization of the layer stack under realistic solar irradiation conditions. Here, we provide a systematic numerical study on the energy yield (EY) of perovskite/CIGS tandem solar modules, optimizing the device architecture with regard to irradiance in various climate zones. In particular, variations of the spectral irradiation and the average photon energy are of decisive importance for the location‐specific optimization of the device architecture. Compared with the reference single‐junction CIGS thin‐film PV technology, we demonstrate a strong improvement in EY (>30%) in perovskite/CIGS thin‐film PV for perovskites of a wide range of bandgaps (1.55 ‐ 2.0 eV), reaching up to 52% improvement in EY for the optimal bandgap (around 1.8 eV). Of the two most favored architectures, the two‐terminal and four‐terminal devices, perovskite/CIGS tandem solar modules with low bandgap (∼1.55 eV) perovskite absorbers in the four‐terminal architecture outperform those in the two‐terminal architecture in average by 3.5% relative. However, for wide perovskite bandgaps ranging from 1.75 eV to 1.85 eV, both architectures perform comparably. The improvements in EY for perovskite/CIGS tandem solar modules highlight the potential of this technology but also the vital need for light management in tandem photovoltaics.

It’s Complicated: A Big Data Approach to Exploring Planetesimal Evolution in the Presence of Jovian Planets

Abstract Previous studies have suggested that the scattered disk is populated by planetesimals that once orbited in the reservoirs between the Jovian planets. Other studies have concluded that the source region for the Centaurs and Jupiter family comets (JFCs) is the scattered disk. Still other studies have suggested dynamical links between Centaurs and JFCs. The overarching goal of this study is to build upon our previous work and, using data mining techniques derived from big data applications, explore a database of close planet/planetesimal approaches in order to both examine these claims and demonstrate how complicated the trajectories of planetesimals wending between the Jovian planets can be—as they are subjected to impulsive alterations by close planetary encounters and resonant effects. Our results show that Centaurs, JFCs, and scattered disk objects are not dynamically distinct populations, and the paths planetesimals take over their lifetimes can be extremely complex. An understanding of this complexity offers solutions to other outstanding questions about the current solar system architecture.

Proof-of-concept analysis of a supplemental solar power system for aircraft

PurposeThis paper aims to analyze the viability of a solar power system as a supplemental power source for commercial and business aircraft.Design/methodology/approachFirst, a model is established to estimate the potential available power from suitable aircraft surfaces for various meteorological conditions, ground and flight mission characteristics. A proposed aircraft system architecture and an associated parametric conceptual sizing model are presented. This supplemental solar power system sizing model is integrated into an aircraft multidisciplinary design optimization environment to evaluate the aircraft-level impact on mission fuel burn. A parametric study for a business jet aircraft is performed to analyze various solar cell types and power densities for converters. Trade-off studies are performed between efficiency and weight.FindingsConsidering today’s efficiency and power-to-weight ratio of the system components, overall fuel burn reduction can be achieved. Therefore, the technology development work can start now to target short to mid-term applications. In addition, promising system integration scenarios are identified, such as the use of solar power for autonomous operation of the air conditioning system on ground, which yield potential further benefit. In conclusion, a supplemental solar power system seems a promising candidate for more efficient aircraft operation.Originality/valueThe presented novel supplemental solar power system architecture concept and its foreseen aircraft integration show potential benefits for near term applications. The results show that the break even for this technology is already reached and therefore build the foundation to further investigate the technology integration challenges. Clear directions for future research and development are outlined enabling the advancement of the technology readiness level.

Solution-Processed "Silver-Bismuth-Iodine" Ternary Thin Films for Lead-Free Photovoltaic Absorbers.

Bismuth-based hybrid perovskites are regarded as promising photo-active semiconductors for environment-friendly and air-stable solar cell applications. However, poor surface morphologies and relatively high bandgap energies have limited their potential. Silver-bismuth-iodine (Ag-Bi-I) is a promising semiconductor for optoelectronic devices. Therefore, we demonstrate the fabrication of Ag-Bi-I ternary thin films using material solution processing. The resulting thin films exhibit controlled surface morphologies and optical bandgaps according to their thermal annealing temperatures. In addition, it has been reported that Ag-Bi-I ternary systems crystallize to AgBi2I7, Ag2BiI5, etc. according to the ratio of the precursor chemicals. The solution-processed AgBi2I7 thin films exhibit a cubic-phase crystal structure, dense, pinhole-free surface morphologies with grains ranging in size from 200 to 800 nm, and an indirect bandgap of 1.87 eV. The resultant AgBi2I7 thin films show good air stability and energy band diagrams, as well as surface morphologies and optical bandgaps suitable for lead-free and air-stable single-junction solar cells. Very recently, a solar cell with 4.3% power conversion efficiency was obtained by optimizing the Ag-Bi-I crystal compositions and solar cell device architectures.

Stability at Scale: Challenges of Module Interconnects for Perovskite Photovoltaics

Uniting efficiency, scalability, and stability is the next frontier for perovskite solar cells. Stability tests conducted on efficient perovskite solar cell mini-module architectures reveal promising stability yet also the stability challenges of scale up.

Fabrication and Demonstration of Planar Micro-Reactors for Solar Steam Methane Reforming

This paper presents a novel solar micro-reactor architecture for cheap hydrogen production by methane reforming. Using microfabrication techniques to create three-dimensional channel networks in diffusion-bonded plates, all the sub-processes required for methane reforming are integrated in a small unit, which is well suited for implementation on cheap and well-established solar parabolic troughs. Monolithic integration of the sub-processes allows heat recovery from the high temperature reaction to the lower temperature endothermic processes such as water vaporization and reagent preheating. To demonstrate the manufacturing feasibility as well as the sufficient catalytic activity, a 4.5W stainless steel demonstrator is built and tested in the laboratory. Results show a complete methane conversion for temperatures over 850°C at a space velocity of 35 000 ml/h*mlcat.

Characterization of chipping and tool wear during drilling of float glass using rotary ultrasonic machining

Float glass’s utility is emerging continuously; major application of float glass is in solar panel and architecture glass. However, the researchers are still bearing drilling problems i.e. chipping near hole’s exit corner and tool wear. Therefore, this study has carried out a designed experimental investigation while drilling float glass by Rotary ultrasonic machining (RUM) process. The authors have made an attempt to estimate the relationship between selected machining parameters i.e. feed rate, vibration amplitude and tool diameter with the chipping amount at hole exit. The core objective is to reduce the chipping by optimizing the opted machining factors. The novelty of this work is a measurement of chipping using coordinate measuring machine (CMM). It is revealed that the least volume of chipping is estimated as 3.81 mm3. The best parametric combination to obtain the least amount of chipping volume is considered as the first level of feed rate (F1), the third level of vibration amplitude (A1) and the first level of tool diameter (TD1). This study investigates the tool wear occurs at three different drilling stages. Tool (6 mm diameter) has carried out least amount of weight loss i.e. 4.78%. The tool which contains the least surface area (integrated lateral and end face) in contact with the workpiece sample has created minimum weight loss.

Solar irradiance forecasting and energy optimization for achieving nearly net zero energy building

Solar energy and the concept of passive solar architecture are being increased in several areas to attain the net-zero energy concept. This paved the way for an increase in the need of solar irradiance forecasting for both solar PV applications and Passive Solar Architectural buildings. First, solar irradiance forecasting was done with 131 400 data sets (1-h data for 15 years) which was split into monthly mean for every year. This model was evaluated by forecasting the post-consecutive years one by one with the pre-consecutive years which includes the pre-forecasted years. This model was shown to have RMSE values of 11% to 24% for various seasonal forecasting using the Random Forest Algorithm in WEKA, which gave the annual irradiance results nearer to the PV Sol energy forecasting results. The R-value was in the range of 0.8 to 0.9 for various seasons which is good. Building Energy Optimization was carried out using BEopt 2.8 software designed by NREL. The chosen building was set to the standard parameters in India, and then, the optimization was done with various customized parameters and systems available in India to reduce the energy consumption from 192.2 MMBtu/yr to 109.1 MMBtu/yr with a 7 kW Solar PV System to attain the net-zero energy concept.

Employing surfactant-assisted hydrothermal synthesis to control CuGaO2 nanoparticle formation and improved carrier selectivity of perovskite solar cells

Delafossites like CuGaO2 have appeared as promising p-type semiconductor materials for opto-electronic applications mainly due to their high optical transparency and electrical conductivity. However, existing synthetic efforts usually result in particles with large diameter limiting their performance relevant to functional electronic applications. In this article, we report a novel surfactant-assisted hydrothermal synthesis method, which allows the development of ultrafine (∼5 nm) monodispersed p-type CuGaO2 nanoparticles (NPs). We show that DMSO can be used as a ligand and dispersing solvent for stabilizing the CuGaO2 NPs. The resulting dispersion is used for the fabrication of dense, compact functional CuGaO2 electronic layer with properties relevant to advanced optoelectronic applications. As a proof of concept, the surfactant-assisted hydrothermal synthesized CuGaO2 is incorporated as a hole transporting layer (HTL) in the inverted p-i-n perovskite solar cell device architecture providing improved hole carrier selectivity and power conversion efficiency compared to conventional PEDOT:PSS HTL based perovskite solar cells.

Mn3O4/PbS thin films: preparation and effect of annealing temperature on some selected properties

Chemical bath deposition was applicable in the deposition of Mn3O4/PbS thin film. The structural, morphological and optical properties of the deposited films showed significant improvement with increase in annealing temperature. X-ray diffraction (XRD) studies showed increase in grain size with increase in annealing temperature. XRD analysis also show the existence of sharp and multiple peaks indicating the polycrystalline nature of the film. The existence of Pb2MnO4 phase was also observed in the XRD patterns. Scanning electron microscope (SEM) results showed increase in grain size and uniformity of grain surface as temperature increases. Optical studies reveal modification in the optical and solid state parameters with increase in annealing temperature. The absorbance increased with annealing temperature exhibiting a maximum in the UV region. Transmittance decreased with annealing temperature exhibiting a minimum in the UV region. The absorption coefficient varied from (0.5–1.5) × 10−4 cm−1 for the as-deposited to (0.5–3.5) × 10−4 cm−1 for the annealed at 473 K and (1.5–5.5) × 10−4 cm−1 for the annealed at 673 K. The band gap decreased from 3.95 eV for the as-deposited to 3.80 eV for annealed at 473 K to 3.70 eV for annealed at 673 K. The high energy gap implies that the thin film can be used for wide variety of applications in solar architecture.

Model Energi Pembangkit Listrik Tenaga Surya di Pulau Giliyang Madura

Giliiyang Island is a famous island that has the highest oxygen content in the world, and very beautiful sea, but the location is far from PLN / elctictric grid system. It is necessary to develop environmentally friendly alternative energy. One of alternative energy offered is solar energy. Solar energy is energy that’s form of light and heat from the sun. This energy can be utilized using a range of technologies such as solar heating, solar photovoltaic, solar thermal power, solar architecture, and artificial photosynthesis. Based on the calculation is known that the electrical energy demand for Giliiyang Island is around 1984 kWh. The design of two off-grid solar power systems which each capacity about 1 MWp will require 3000 m2 of land with 780 solar panels that have an intensity of 800 W / m2. Deep cycle battery with 24 V DC 200 AH as storage media required about 504 pieces.

Solar PV-Based Scalable DC Microgrid for Rural Electrification in Developing Regions

In this paper, we detail the design, analysis, and implementation of a highly distributed off-grid solar photovoltaic dc microgrid architecture suitable for rural electrification in developing countries. The proposed architecture is superior in comparison with existing architectures for rural electrification because of its 1) generation and storage scalability, 2) higher distribution efficiency (because of distributed generation and distributed storage for lower line losses), 3) ability to provide power for larger communal loads without the requirement for large, dedicated generation by extracting the benefit of usage diversity, and 4) localized control by using the hysteresis-based voltage droop method, thus eliminating the need for a central controller. The proposed microgrid architecture consists of several nanogrids capable of the self-sustained generation, storage, and bidirectional flow of power within the microgrid. Bidirectional power flow and distributed voltage droop control are implemented through the duty cycle control of a modified flyback converter. A detailed analysis in terms of power flow, loss, and system efficiency was conducted by using the Newton–Raphson method modified for dc power flow at varying distribution voltages, conductor sizes, and schemes of interconnection among the contributing nanogrids. A scaled-down version of the proposed architecture with various power sharing scenarios was also implemented on hardware, and yielded satisfactory results.