Energy Resources Research Articles

Assessing Photo-Voltaic Potential in Urban Environments: A Comparative Study between Aerial Photogrammetry and LiDAR Technologies

Abstract. Urban development and population growth have significantly increased energy demands, predominantly met by non-renewable resources, negatively impacting nature and climate. Consequently, there has been a global shift towards renewable energy sources, with solar energy being widely adopted. Photovoltaic (PV) potential measures the usable electricity from solar energy using PV technology. With conventional methods, estimating PV potential involves converting 3D point cloud data to 2.5D elevation models, which can affect the accuracy of the estimation. A research gap exists in using adequate 3D point cloud datasets for PV potential estimation considering roof surface area and the surface normal vectors. This study compares aerial photogrammetry and aerial LiDAR point clouds for PV potential estimation against the DSM-based approach. Accurate PV potential estimation must consider solar incidence, roof area, azimuth, tilt angles, and PV efficiency. Traditional 2.5D methods often overlook crucial azimuth and tilt data, limiting the accuracy of the PV estimation. Converting 3D data to 2.5D may result in information loss, while 3D analyses offer higher accuracy. To investigate the mentioned gaps, this research aims to evaluate the capabilities of photogrammetry and LiDAR for urban PV potential estimation, highlighting their feasibility and accuracy over 2.5D methods.

Distillery-Waste-Derived C-SiO2 Catalyst Support Reinforces Phenol Adsorption and Selective Hydrogenation.

Selective hydrogenation of lignin-derived phenolic compounds is an essential process for developing the sustainable chemical industry and reducing dependence on nonrenewable resources. Herein, a composite C-SiO2 material (DGC) was prepared via the stepwise pyrolysis and steam activation of the distiller's grains, a fermentation solid waste from the Baijiu industry. After Ru loading, Ru/DGC was used for the catalytic hydrogenation of phenol to cyclohexanol. Steam activation remarkably increased the hydrophilicity and specific surface area of DGC and introduced oxygen-containing functional groups on the surface of DGC, promoting the adsorption of Ru3+. Furthermore, the steam activation of DGC promoted the graphitization of the carbon matrix and formed Si-H/Si-OH bonds on the SiO2 surface. The benzene ring of phenol interacted with the carbon matrix via π-π stacking, and the hydroxyl group of phenol interacted with SiO2 via hydrogen bonding. The synergistic interactions of phenol at the C-SiO2 interface enhanced phenol adsorption to promote the hydrogenation. Consequently, 100% of phenol was hydrogenated to cyclohexanol at 60 °C within 30 min. Furthermore, the optimized catalyst exhibited high activity for phenol hydrogenation even after four reuse cycles. The outstanding stability of the catalyst and its requirement for mild reaction conditions favor its large-scale industrial applications.

Synergetic Combination of Bio‐Electrolytes and Bio‐Fluidic Channels as a Novel Resource of Sustainable Energy

AbstractExploration for sustainable energy resources is essential to minimize the dependence on fossil fuels and to improve environmental parameters. Here, the possibility of utilizing bio‐waste‐derived electrolytes as an electrical energy resource by placing them across semipermeable membranes prepared through parallel stacking of coir fibers is examined. The nanofluidic membrane (d‐CF‐V) prepared by modifying the inner walls of the bio‐fluidic channels with atomically thin layers of vanadium pentoxide (VO) shows excellent perm‐selectivity (t+ = 0.87, with 1000‐fold concentration difference) and electricity conversion efficiency (≈ 28.2%). With simulated sea and river water, the d‐CF‐V yields output energy up to 2.4 W m−2, similarly with mineral acid bases (0.5 m HCl and 0.01 m NaOH), the d‐CF‐V shows an energy output of 11.8 W m−2. The sun‐dried Garcinia morella (Kuji thekera), and charred peels of Musa balbisiana (banana) are used as sustainable sources of bio‐electrolytes, which in combination with permselective d‐CF‐V yielded a power density of ≈1.4 W m−2. By replacing standard Ag/AgCl electrodes with nanomaterials exhibiting contrasting charge transfer activities, oxidized carbon nanotube membrane (o‐CNT) and polyaniline (PANI) membrane the output voltage is enhanced from –127 to –568 mV and current output is increased from 10.2 to 51.5 µA.

Do Energy Efficiency and Technology Boost Sustainable Environment: Evidence from GCC Countries

Sustainable Environment practices significantly reduce carbon emissions by ensuring the continuous use of materials and energy resources, thus making them intrinsically aligned with the underlying objectives of the decarbonization agenda. Technological advancement has the potential to contribute significantly to this shift by streamlining resource flows, enhancing waste management procedures, and allowing more efficient energy consumption. Although Gulf Cooperation Council countries have experienced robust economic growth over the decades, rising pollution emissions and low renewable energy consumption have raised concerns among policymakers about the long-term stability of this growth. In recent years, Gulf countries have paid significant concern to environmental matters and achieved carbon-free development. This study seeks to investigate the relationship between energy efficiency, technology, and sustainability, particularly emphasizing the green economy perspective. Carbon dioxide emission taken as the dependent variable. Frontier Technology Readiness Index reflects the utilization of technology within economies. Energy efficiency is also considered, symbolizing the transition from fossil fuels to green energy due to technological progression in the energy sector. The findings suggest that factors such as the Frontier Technology Readiness Index, the energy intensity level of primary energy, and medium and high-tech manufacturing significantly harm the environment, while scientific and technical journal articles and agriculture significantly improve the environment over time. To improve Gulf Cooperation Council countries' environmental quality, policymakers must understand the factors causing climate change. This study gives policymakers useful information about how to make the Gulf Cooperation Council community more sustainable by looking at energy efficiency, technology, and digital adaptation.

Water-Energy-Food Communities in South Africa: Exploring Multi-Actor Governance Instruments Contributing to Social Justice

Abstract South Africa faces significant challenges concerning the scarcity and unequal distribution of water, energy and food resources. The Constitution of the Republic of South Africa, 1996 underscores the importance of social justice and mandates collaboration among all levels of government and state entities. To effectively address the interconnected nature of these resources, a collaborative governance approach is necessary. This article introduces the concept of ‘Water-Energy-Food (wef) communities’, a concept not currently recognised in South African law, drawing inspiration from the European Union’s Renewable Energy Directive (res-Directive) of 2018 and the Electricity Market Directive (E-Directive) of 2019 that introduced the concept of ‘energy communities’. wef communities, operating at the local level, could integrate improved governance and decision-making in the water, energy, and food sectors, thereby advancing social justice in local communities. The article compares existing multi-actor governance instruments in South African law and uses the EU law as learning points for the establishment of wef communities as opposed to energy communities that focus on one determinant only. Although the current South African multi-actor governance instruments do not explicitly address an integrated wef governance approach, they may serve as a basis for proposing framework rules to establish wef communities, highlighting their potential to achieve social justice goals in relation to their access to water, energy and food. The article proposes rules for the potential establishment of wef communities, taking learning points from the EU directives as well as existing South African instruments.

Natural fiber reinforced cementitious composites; materials, compatibility issues and future perspectives

ABSTRACT Research on the sustainable production of building materials has been increasing from time to time. The construction industry is one of the sectors that leads to the depletion of significant amounts of nonrenewable resources, such as minerals. The ecosystem is deteriorated, and carbon dioxide (CO2) emissions are enormous in the environment due to the use of fossil fuel-based materials. The purpose of this paper is to review the use of plant fibers (hereafter NF) for reinforcement in cementitious concrete. Concrete, plant fibers, their chemical nature, and characteristics are highlighted in an overview. The most important issues in NF-concrete compatibility were discussed, which could provide research opportunities. Modification of NFs and the cement matrix are examined as methods for improving compatibility and degradation. Moreover, the properties and longevity of cementitious materials that are reinforced with natural fibers are also examined. Finally, the review emphasizes the significant research gaps and future research prospects identified in the reviewed papers.

Role of Morphology on Zinc Oxide Nanostructures for Efficient Photoelectrochemical Activity and Hydrogen Production.

Energy generation today heavily relies on the field of photocatalysis, with many conventional energy generation strategies now superseded by the conversion of solar energy into chemical or thermal energy for a variety of energy-related applications. Global warming has pointed to the urgent necessity of moving away from non-renewable energy sources, with a resulting emphasis on creating the best photocatalysts for effective solar conversion by investigating a variety of material systems and material combinations. The present study explores the influence of morphological changes on the photoelectrochemical activity of zinc oxide nanostructures by exploiting electrodeposition and capping agents to control the growth rates of different ZnO facets and obtain well-defined nanostructures and orientations. A zinc nitrate (Zn (NO3)2) bath was used to electrodeposit ZnO nanostructures on an indium tin oxide glass (ITO) substrate at 70 °C with an applied potential of -1.0 V. Ethylenediamine (EDA) or ammonium fluoride (NH4F) were added as capping agents to the zinc nitrate bath. Extensive evaluation and characterization of the photoelectrochemical (PEC) capabilities of the resulting morphology-controlled zinc oxide nanostructures confirmed that altering the ZnO morphology can have positive impacts on PEC properties.

Reducing uncertainties of climate projections on solar energy resources in Brazil.

The share of solar power in Brazil's electrical grid has rapidly increased, relieving GHG emissions and diversifying energy sources for greater energy security. Besides that, solar resource is susceptible to climate change, adding uncertainty to electrical grid resilience. This study uses satellite and reanalysis data to evaluate the performance of CMIP6 models in replicating and predicting surface solar irradiance (SSR) in Brazil. The results from the most reliable models indicate an increase in SSR by 2% to 8% in most regions, with a decrease of around 3% in the South. These findings highlight the potential for increased photovoltaic (PV) yield if backed by supportive public policies while underlining the importance of uncertainty assessment of climate models.

A comparative analysis of intelligent energy modelling approaches for a grid-tied PVT system application

Renewable energy resources are a long-term answer to the current chronic energy dilemma. Solar photovoltaic (PV) systems are the most often used form of a practical solution for power supply and energy management in buildings. A PV-thermal (PVT) system is essential to lowering the demand for grid energy by capturing electrical and thermal energy from sunlight, optimising energy usage and encouraging sustainable energy practices. The most significant difficulty faced by developing countries, such as South Africa, is a lack of power supply to meet demand while limiting grid overload. An alternative source of energy is a critical component. This research compares two intelligent energy modelling methodologies: optimal control scheme-based open loop and model predictive control (MPC) in a PVT application. The primary goal of the modelling is to limit the electricity required from the grid while stressing the system’s energy efficiency and cost-effectiveness. The open loop approach uses mathematical optimisation techniques to establish the best control strategy for the PVT system. The ideal set-points for various system parameters are found by presenting the problem as an optimisation task to reduce grid power usage. The optimal control technique delivers a global optimisation solution based on the system dynamics and constraints. The MPC technique employs a predictive control technique of the PVT system to create optimal control actions in a receding horizon manner. The MPC algorithm anticipates future system behaviour and generates control actions that minimise grid power drawn by iteratively solving an optimisation problem at each time step. This robust online control scheme enables real-time modifications and responses to system disruptions that effectively and dynamically coordinate system behaviour.

Impacts of renewable energy resources on the weather vulnerability of power systems

Impacts of renewable energy resources on the weather vulnerability of power systems

A new combined analytical–numerical probabilistic method for assessing the impact of DERs on the voltage stability of bulk power systems

The integration of distributed energy resources (DERs) and unpredictable loads has increased uncertainty in power systems. Traditional methods struggle to assess performance under these uncertainties, and existing probabilistic methods face challenges with complexity and accuracy. This paper introduces a new combined analytical–numerical probabilistic method to assess the impact of DERs on voltage stability. Using Bayesian Parameter Estimation (BPE), the method derives the analytical properties of random variables (RVs) associated with DERs and loads, obtaining posterior distributions. The Metropolis–Hastings sampling technique then estimates these posteriors numerically, enabling accurate predictions of DERs and load outputs. Voltage stability analysis was performed using the continuation power flow method and validated on the IEEE 59-bus test system in MATLAB/Simulink. The results show that integrating DERs significantly improves voltage stability. The proposed method outperforms the Monte Carlo simulation (MCS)-based method in accuracy and computational speed, increasing DERs penetration and voltage stability limits by 3%. It closely matches MCS voltage estimates but requires fewer iterations (500 per loading increment) compared to MCS’s 1000, leading to faster computation times (a few hours to one day versus up to three days for MCS). This method provides an efficient solution for managing uncertainties in power systems.

Biomass Energy from Agricultural Waste: Evaluating Groundnut Vines and Pumpkin Straws for Combustion Performance

Energy demand has risen significantly in developing countries due to rapid population growth and increase in economic activities such as industrialization, automation manufacturing and digitalization. Dependency on conventional sources of energy in both rural and peri-urban is high. Traditional energy resources lead to environmental degradation due to carbon oxide release leading global warming and deforestation which results to hydrological decline; therefore, need to come up with renewable resources from other sources such as agricultural wastes to meet the demand and solve environmental pollution problems. This study carried out an investigation on combustion and performance analysis of pumpkin straws and groundnut vines to establish their energy potential. ASTM standards were used to determine the proximate and ultimate properties. This analysis revealed moisture content (8.7-12.4%), volatile matter (63-69%), fixed carbon (11.5-18.5%), ash content (6.3-8.2%), Sulphur (0.09-0.13%), nitrogen (1.02-1.03%), oxygen (5.01-55.88%), carbon (41.8-43%) and hydrogen (5.96-6.3%). Calorific values for the briquettes were above 4389 kCal, which is above most biomass. The density and compressive strength were above 0.63 g/cm3 and 17N/mm2 respectively from compaction pressure of 150, 250 and 350 kg/cm2. The burning time was between 4 and 5.3 min, showing an increase with compaction pressure, burning rate ranged between 4.3 and 2.9 g/min, a decrease with compaction pressure increase. The specific fuel consumption portrayed an inverse relationship with calorific value and a direct relationship with compaction pressure, ranging between 166 to 176 grams per litre. Temperature-weight analysis revealed thermo stability of this feedstock, portraying resemblance to proximate analysis. Having exhibited close relationship to other agricultural wastes used for fuel, groundnut vines and pumpkin straws are a solution to environmental degradation by reducing deforestation and emissions. It is recommended that further research on mixing this feedstock with other agricultural wastes as well as making and testing of pellets be carried out to maximize energy output.

Development of the Recycling Industry Sector in Bulgaria in the Context of the Circular Economy Concept

The article examines the structure and results of the activities of enterprises from the raw materials and materials recycling sector in Bulgaria by subsectors from the National Classifier of Economic Activities (NCEA 2008). The article examines the structure of the recycling industry sector of the national economy with enterprises and resp. the results achieved by them in each of the directions – waste collection, waste recycling and waste disposal. The research interest and choice of this sector of the national economy is not accidental. It is provoked by its importance for building a circular economy, the fight against climate change and the concept of secondary utilization of the exhaustible resources of our planet. The purpose of the article is to make a comparison and outline the directions of development of the enterprises from the recycling industry in Bulgaria in comparison with the general economic development of the country in recent years. Statistical data for the enterprises from the recycling industry were used in relation to selected economic indicators – turnover, value of long-term tangible assets, value of short-term tangible assets, employed personnel, investments made, etc. At the national macro level, and as a basis for comparison, the main macroeconomic indicators are observed – gross domestic product, gross domestic product per capita and foreign direct investments. By using the methods of comparison, retrospective analysis, technical analysis, etc. principles and regularities in the economic development of the sector and its importance for the general economic development of the country have been identified.

Causes of Drug Use and Methods of Legal Treatment

Drug addiction or use dates back to ancient times, with its roots lying in the human use of certain plants containing substances that alter mental states, perception, and sensations for thousands of years. These substances were used either to experience pleasure, alleviate the pain of a particular patient, endure suffering, or forget a painful life and its burdens. Drugs play a significant role in encouraging individuals to commit various crimes due to their impact on the nervous and sensory systems. Furthermore, drug abuse has become one of the most pressing problems and challenges facing our society, posing severe threats to families and youth and warning of potential disintegration. Regardless of the form or type of drug, it remains one of the most dangerous social issues and plagues that harm our community due to its profoundly negative effects on individuals, families, and society at large.One of the causes behind the prevalence of drug use is the high unemployment rate and lack of job opportunities within Iraqi society, leading to idle individuals who, with excess free time, may turn to drug addiction. Additionally, poverty becomes a bias, with the influential factor being the creation of a strong and urgent desire that drives drug users to obtain substances by any means and gradually increase their dosage. Other significant causes of drug use or addiction include family environment, bad company, working conditions, general social influences, or the desire to escape from one's social or economic reality. In some cases, sudden wealth among certain families may also contribute to drug abuse. As a result, drug abuse has become a focal issue throughout Iraq due to its destructive impact on Iraqi society. It is a primary factor in numerous social, security, economic, and health problems, leading Iraqi society to invest considerable energy and financial resources in preventing its spread and mitigating its effects on individuals and the community. This has been addressed through various legal and other means. The significance of this study lies in understanding how drug users can reintegrate into society as normal individuals without suffering from physical or psychological disorders resulting from drug addiction. This can only be achieved through understanding and addressing treatment methods and attempts to eliminate the causes of drug use or addiction. Officials must exercise caution and consider this issue to ensure that drug users are free from drugs and their negative consequences

Event-Triggered Fuzzy Adaptive Predefined-Time Control for Fractional-Order Nonlinear Systems with Time-Varying Deferred Constraints and Its Application

This paper focuses on the fuzzy adaptive predefined-time control for fractional-order nonlinear systems with time-varying deferred constraints. First, a modified dynamic surface control technique is introduced to address the problem of computational complexity exposed in the backstepping framework, and the interval type-2 fuzzy logic systems are applied to model the unknown nonlinearities of the systems. Next, a shifting function and the barrier Lyapunov function with variational barrier bounds are formulated to deal with the constraints issue. Particularly, the constraint conditions can be satisfied within a predetermined time, even if they are transgressed initially. Furthermore, a switching threshold event-triggered controller is devised to balance the control energy and communication resources. With the help of the predefined-time stability criterion, it is proven that the presented predefined-time event-triggered controller can ensure that all the signals involved in the closed-loop system are bounded and the tracking error fluctuates to a small neighborhood of the origin in a predefined-time interval. Finally, two simulation examples are provided to confirm the effectiveness of the put-forward control algorithm.

Mechanisms of roasting for improving rare earth element leaching from coal gangue

ABSTRACT Coal resources represent an important potential source for the future extraction of rare earth elements (REEs). This study, combining microscopic characterization techniques and experimental analysis, investigates the occurrence characteristics of REEs in coal gangue and the roasting activation mechanisms. The study reveals that phosphate minerals are the primary carriers of REEs, and sequential chemical extraction results further confirm the close association between REEs and phosphate minerals. Roasting at around 600°C facilitates the release of REEs from organic matter and clay minerals like kaolinite, significantly improving leaching efficiency. Under leaching conditions of 20 g/L, 50°C, 0.5 M HCl, and 1000 RPM, the leaching of REEs can reach approximately 80%. However, when the roasting temperature exceeds 1000°C, the formation of mullite leads to mineral surface sintering, reducing the recovery of REEs. This study emphasizes the importance of optimizing roasting conditions and understanding mineral phase changes to maximize REEs recovery, which is crucial for sustainable resource management and environmental remediation.

Prediction of Heat Transfer in a Hybrid Solar–Thermal–Photovoltaic Heat Exchanger Using Computational Fluid Dynamics

Solar energy is one of the main renewable energy resources due to its abundance. It can be used for two purposes, thermal or photovoltaic applications. However, when the resource obtained is mixed, it is called photovoltaic thermal hybrid, where the solar panels generate electricity and are provided with a heat exchanger to absorb energy through a water flow. This is one of the techniques used by the scientific community to reduce the excess temperature generated by solar radiation in the cells, improving the electrical efficiency of photovoltaic systems and obtaining fluid with higher temperature. In this work, the thermal behavior of a heat exchanger equipped with fins in its interior to increase the thermal efficiency of the system was analyzed using CFD (Computational Fluid Dynamics). The results showed that the average fluid outlet temperature was 75.31 °C, considering an incident irradiance of 1067 W/m2 and a fluid inlet temperature of 27 °C. The operating conditions were obtained from published experimental studies, achieving 97.7% similarity between the two. This was due to the boundary conditions of the heat flux (1067 W/m2) impinging directly on the coupled cells and the heat exchanger in a working area of 0.22 m2.

How Two‐Dimensional Heterocovariance Spectroscopy and Data Fusion Level out the Inadequacies of Compact Spectrometers

ABSTRACTOver the past decade, sensors and compact spectrometers have emerged as a powerful means for real‐time monitoring of chemical and biochemical processes in the field of process analytical technologies (PATs). This is largely attributed to cost‐efficiency and their robustness in near‐line applications. In comparison to more sophisticated laboratory instruments, these devices exhibit limited sensitivity and resolution. In this study, a combination of near‐infrared, low‐field 1H nuclear magnetic resonance and compact Raman spectrometers were employed for the process monitoring of the acid‐catalyzed esterification of isoamyl alcohol and acetic acid to isoamyl acetate. The resulting real‐time data were transformed and visualized for interpretation using two‐dimensional heterocovariance spectroscopy. The data were also subjected to pretreatment, concatenation, and multivariate analysis in accordance with low‐ and mid‐level data fusion. The spectral interpretation derived from heterocovariance spectroscopy provided support for the data pretreatment during data fusion. By applying these computational techniques, the inherent limitations of sensitivity and resolution associated with compact spectroscopic instruments could be overcome, thereby facilitating the interpretation of data and yielding further insights into the process under study. A comparison of the process parameters resulting from the applied methods indicated that consistent data could be obtained. This study demonstrates that heterocovariance spectroscopy and data fusion allow to enhance compact, less expensive analytical instruments for process monitoring and to acquire process knowledge. This, in turn, enables material, financial, and energy resources to be conserved.

On-Grid Hybrid Wind–Solar Power Plants in Ukraine’s Residential Sector: Economic Justification of Installation Under Different Support Schemes

On-grid hybrid wind–solar systems are one of the best sustainable solutions for developing distributed generation, as they can provide a stable and reliable electricity supply, effectively using the potential of the two most common renewable energy resources. In Ukraine, promoting the development of on-grid hybrid wind–solar power plants takes on particular importance under conditions of electricity shortages caused by the large-scale destruction of the energy infrastructure due to the ongoing hostilities. This article examines the economic efficiency of installing such power plants in the residential sector of Ukraine under different state support schemes. This study was conducted for on-grid hybrid wind–solar systems of various configurations and installed capacities with different equity and debt capital proportions involved in implementing investment projects. This study’s results highlight the economic efficiency of the feed-in tariff compared to the net billing for households investing in such facilities and emphasize the need to improve policy measures to increase their investment attractiveness.

Re-interpreting renewable and non-renewable water resources in the over-pressured Pannonian Basin

With climate change, population growth and the resulting escalating water shortage, humanity is increasingly turning to non-renewable and even fossil groundwater resources, which poses a major challenge to sustainable water management. In this study, 2D basin-scale numerical simulations were carried out on the COMSOL Multiphysics® finite element numerical platform to identify non-renewable water resources in the Central Pannonian Basin (Central Europe, Hungary) based on the lack of hydraulic connection to recharge areas. The concept and boundary conditions (fixed water table configuration at the top, pressure-elevation profiles on the lateral sides, and constant pressure on the bottom) were derived from a previous basin-scale hydraulic data evaluation study, while the hydrostratigraphic subdivision was based on seismic and well log interpretations. As a result, topography-driven groundwater flow systems fed by meteoric water infiltration were separated from a transition zone, which contains non-renewable groundwater resources and covers 85% area of the simulated 110 km long and roughly 1600 m deep cross-section what was previously thought to be fully renewable. Such complex flow pattern and re-interpretation of the renewable and non-renewable groundwater resources can be expected in any terrestrial sedimentary basin with over-pressured flow domains.