Reliable Energy Source Research Articles

Economic feasibility study for wave energy conversion device deployment in Faroese waters

As the world continues to battle with increasing energy demand along with the serious effects of climate change, there is a need for more reliable renewable energy sources. The objective of the present work is to study the economic feasibility for deployment of wave energy conversion devices in the Faroese coastal region. We analyze eight different wave energy conversion concepts under development at nine different nearshore locations in the Faroese coastal region. The nine different locations are classified into three coastal locations — three on the west coast, three on the east coast and three on the north coast. The eight wave energy conversion devices mostly rely on different working principles, though some of these are similar. Results show that there is quite a significant difference in the performance of the devices from coast to coast. There is also a difference between the different conversion devices as they rely on different principles and the suitability of each device varies from location to location. We also show that the Faroe Islands are a suitable location for wave energy converter deployment compared to other places. Furthermore, results show that the performance of wave energy converters in the Faroe Islands can prove to be a direct competitor to offshore floating wind energy.

CFD analysis of novel two-pass, sinusoidal corrugated, trapezoidal channel for solar air heater

Solar is regarded as a clean and reliable source of energy. Solar air heaters (SAHs) are one of the most prevalent applications of solar energy. SAHs have normally low thermal efficiency. In order to increase thermal efficiency, a sinusoidal wave corrugation is employed on the base wall of the twin-pass channel of an absorbent plate with a sharp bend. A parametric study was conducted to study the effect of flow and geometric parameters i.e. wave height, pitch, and propagation angle of the wave with respect to flow inlet on performance parameters. Computational Fluid Dynamics (CFD) tool was implemented to examine the performance parameters i.e. heat transfer enhancement, pressure drop, and thermal performance factor. In comparison to the orthogonal ones, inclined corrugation is more efficient in terms of heat transfer. With the increase in roughness height, pitch, and corrugation angle, an increasing trend was observed in Thermal Performance Factor, followed by a diminishing trend. The corrugated channel having a roughness height ratio of 19, two waves in a single block with a 45° wave propagation angle seemed to be an optimal configuration with 35% enhancement in thermal performance factor as compared to the smooth channel, hence representing promising augmentation.

Wind power anomaly data detection based on unsupervised methods

During the actual operation of the wind turbine, a large number of abnormal data will be generated due to environmental or human factors, which will have a great impact on the condition assessment and output prediction. In order to make wind energy a reliable source of energy, it is very important to establish an efficient and accurate wind power detection model. Therefore, it becomes essential to identify abnormal data for a more precise evaluation of wind turbine performance. Based on the data mining clustering technology K-means algorithm, this paper introduces an unsupervised abnormal wind power detection algorithm combining the variational autoencoders (VAE) model. The focus of this abnormal wind power detection method is primarily on assessing the reconstruction error, which, in turn, generates an abnormality score for wind power data. This score is then used to determine the presence of abnormal wind power data. Finally, the wind power data in 2021 is tested.

Superaerophobic/Superhydrophilic Multidimensional Electrode System for High-Current-Density Water Electrolysis.

Water electrolysis is emerging as a promising renewable-energy technology for the green production of hydrogen, which is a representative and reliable clean energy source. From economical and industrial perspectives, the development of earth-abundant non-noble metal-based and bifunctional catalysts, which can simultaneously exhibit high catalytic activities and stabilities for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER), is critical; however, to date, these types of catalysts have not been constructed, particularly, for high-current-density water electrolysis at the industrial level. This study developed a heterostructured zero-dimensional (0D)-one-dimensional (1D) PrBa0.5Sr0.5Co1.5Fe0.5O5+δ (PBSCF)-Ni3S2 as a self-supported catalytic electrode via interface and morphology engineering. This unique heterodimensional nanostructure of the PBSCF-Ni3S2 system demonstrates superaerophobic/superhydrophilic features and maximizes the exposure of the highly active heterointerface, endowing the PBSCF-Ni3S2 electrode with outstanding electrocatalytic performances in both HER and OER and exceptional operational stability during the overall water electrolysis at high current densities (500 h at 500 mA cm-2). This study provides important insights into the development of catalytic electrodes for efficient and stable large-scale hydrogen production systems.

Condition Monitoring of Wind Turbine Drivetrain Bearings

Abstract As an extremely valuable and reliable energy source, the renewable energy is developing around the world at an unprecedented pace. By the end of 2022, the global installed capacity of offshore wind turbines is expected to reach 46.4 GW, among which 33.9 GW in Europe. Efficiencies in Operations and Maintenance (O&M) offer potential to achieve significant cost savings as it accounts for around 20%–30% of overall offshore wind farm costs. A recent study of approximately 350 offshore wind turbines indicates that gearboxes might have to be replaced as early as 6.5 years. Therefore sensing and condition monitoring (CM) systems are needed in order to obtain reliable information on the state and condition of different critical parts. The development and use of such technologies will allow companies to schedule actions at the right time. The reduced costs of O&M enable the wind energy at a competitive price thus strengthening productivity of the wind energy sector. At the academic level, a plethora of methodologies have been proposed during the last decades focusing toward early and accurate fault detection. Among others, Envelope Analysis is one of the most important methodologies, where the envelope of the vibration signal is estimated, usually after filtering around a selected frequency band excited by impacts due to the faults. Different tools, such as Kurtogram, have been proposed in order to accurately select the optimum filter parameters (center frequency and bandwidth). Cyclostationary analysis and corresponding methodologies, i.e., the cyclic spectral correlation and the cyclic spectral coherence, have been proved as powerful tools for CM. On the other hand the application, test, and evaluation of such tools in general industrial cases is still rather limited. Therefore the main aim of this paper is the application and evaluation of advanced diagnostic techniques and diagnostic indicators, including the Enhanced Envelope Spectrum and the Spectral Flatness on real-world vibration data collected from vibration sensors on gearboxes in multiple wind turbines over an extended period of time of nearly four years. The diagnostic indicators are compared with classical statistic time and frequency indicators, i.e., Kurtosis, Crest Factor, etc. and their effectiveness is evaluated based on the successful detection of two failure events.

How does the space of production wells influence the heat extraction efficiency?–defined by a 3D modeling work in enhanced geothermal system (EGS)

The space of production well plays a crucial role in the heat extraction performance of the Enhanced Geothermal System (EGS), which have the potential to meet the growing global energy demand as a reliable energy source. Nonetheless, there has been insufficient research and attention focused on comprehending the impact of the space of production well on the efficiency and effectiveness of EGS. In this work, a series of numerical simulations were conducted to assess the impact of the space of production well on heat extraction efficiency in EGS. Three different cases were considered: Case 50 with 50 m production well spacing, Case 100 with 100 m production well spacing, and Case 150 with 150 m production well spacing. At the X-Y plane and Y-Z plane, the simulation results indicated that there were slight differences in temperature variation among the Case 50, Case 100 and Case 150. And the cooling area decreasing as the spacing of production wells decreased. Moreover, the delivery of cooling water via the injection well and its subsequent distribution to various reference points lead to a decline in temperature at each point, albeit with varying degrees of variation. Besides, the established efficiency (ef) for Case 50 is smaller than the Case 100 and Case 150 during the last 15 years. These findings contribute valuable insights to the exploration and exploitation of EGS systems and can serve as a guide for further research in this field.

Modeling of Optimal Power Generation in Small Hydropower Plants

Abstract Small hydropower plants (SHPs) have gained international attention as a reliable and versatile renewable energy source. Unfortunately, this energy source is not used efficiently. This is because these systems utilize headwaters with lower water capacity called forebays instead of large water reservoirs like dams. Since this hinders the control of electricity generation, the headwater is either wasted before it can be converted into electricity or it is exhausted very quickly and electricity generation stops after a short time. The aim of this study is to prevent the loss of electricity generation through the efficient use of SHP headwater. For this purpose, a mathematical model was created based on two SHPs operating in tandem. The mathematical model obtained was analyzed, and forebay water level simulation graphs for electricity generation at water flowrates of 2000, 4000, 6000, and 8000 kg/h were obtained. With the help of the obtained graphs, critical wicket gate openings for maximum electricity generation at flowrates of 2000, 4000, 6000, and 8000 kg/h were calculated. The results of this study are applicable to all SHPs. These results are also promising in terms of optimizing the use of a renewable energy source.

IMAGE PROCESSING AND CNN BASED MANUFACTURING DEFECT DETECTION AND CLASSIFICATION OF FAULTS IN PHOTOVOLTAIC CELLS

Renewable energy resources such as solar energy, biomass, tidal, geothermal, and hydroelectric energy are becoming increasingly important due to their potential to mitigate the negative impacts of climate change and reduce our dependence on finite and polluting fossil fuels. Solar power can provide a clean, sustainable, and reliable source of renewable energy. Important component of solar power generation is the silicon panel and its surface quality is highly related to its robustness and power generation efficiency. Cell breakages resulting from micro-cracks, degradation and shunted areas on cells are proven to cause major issues and these affect the photovoltaic module efficiency and performance. Solar cell defect identification is important because defects in solar cells significantly reduce their efficiency, which in turn affects their power output and lifespan. By identifying and classifying defects during the production of these cells, engineers and researchers can improve the quality control of solar cells, leading to more reliable and efficient solar energy systems. The proposed method in this research paper, utilizes image processing operations such as adaptive Gaussian thresholding, horizontal and vertical line extraction morphological operations, Canny edge detection, K- Means clustering and VGG16 convolutional neural network to identify the defects in solar cells and classify them as defective or non-defective during the manufacturing process itself. Once the defects are classified, the classification data is exported to Excel file and the results are visually represented as labelled images. OpenCV and Keras modules in Python are used to perform the image processing operations which contributes to cost-effective, reduced computation and high-precision solution.

Two‐Dimensional Metallophthalocyanine Nanomaterials for Electrocatalytic Energy Conversion

Growing energy demand drives the rapid development of clean and reliable energy sources. In the past years, the exploration of novel materials with considerable efficiency and durability has drawn attention in the area of electrochemical energy conversion. Transition metal macrocyclic metallophthalocyanines (MPcs)‐based catalysts with a peculiar 2D constitution have emerged with a promising future account of their highly structural tailorability and molecular functionality which greatly extend their functionalities as electrocatalytic materials for energy conversion. This review summarizes the systematic engineering of synthesis of MPcs and their analogs in detail, and mostly pays attention to the frontier research of MPc‐based high‐performance catalysts toward different electrocatalytic processes concerning hydrogen, oxygen, water, carbon dioxide, and nitrogen, with a particular focus on discussing the interrelationship between the electrocatalytic activity and component/structure, as well as functional applications of MPcs. Finally, we give the gaps that need to be addressed after much thought.

Recent Developments in Materials for Physical Hydrogen Storage: A Review.

The depletion of reliable energy sources and the environmental and climatic repercussions of polluting energy sources have become global challenges. Hence, many countries have adopted various renewable energy sources including hydrogen. Hydrogen is a future energy carrier in the global energy system and has the potential to produce zero carbon emissions. For the non-fossil energy sources, hydrogen and electricity are considered the dominant energy carriers for providing end-user services, because they can satisfy most of the consumer requirements. Hence, the development of both hydrogen production and storage is necessary to meet the standards of a "hydrogen economy". The physical and chemical absorption of hydrogen in solid storage materials is a promising hydrogen storage method because of the high storage and transportation performance. In this paper, physical hydrogen storage materials such as hollow spheres, carbon-based materials, zeolites, and metal-organic frameworks are reviewed. We summarize and discuss the properties, hydrogen storage densities at different temperatures and pressures, and the fabrication and modification methods of these materials. The challenges associated with these physical hydrogen storage materials are also discussed.

Selection of a reliable energy source suppling domestic hot water (DHW) system in the kindergarten – a case study

Renewable energy sources (RESs) are used more and more frequently as energy sources for heating and domestic hot water (DHW). However, there are many factors influencing the energy efficiency, thus also ecological benefits. Before making a decision what kind of RES is useful and reliable, a comprehensive analysis should be conducted taking into account technical, financial and ecological factors. This paper discusses different variants of energy sources that could be applied in a kindergarten building for preparing hot water, in place of existing solution (district heating system, DHS). An air heat pump (AHP) with photovoltaic panels (PV) were considered the most reliable energy sources in the analysed building, in terms of economic and environmental considerations. The simple payback time (SPBT) for this investment was estimated as 14.55 years. This solution causes the lowest CO2 emissions. Another system with solar collectors supplying hot water preparation in the heat center can be also recommended. The simple payback time in this case was slightly higher (14.94 years) and what is more, a decrease in CO2 emissions was observed compared to the actual conditions.

A state-of-the-art review of energy-efficient and renewable energy systems in higher education facilities

Amid escalating energy demands and growing environmental concerns, educational institutions are transforming into crucibles for enduring innovation. This comprehensive review summarizes the complex relationship between Energy Efficiency and Renewable Energy Systems (EERES) within the sphere of educational institutions. By instituting Energy Efficiency initiatives, organizations can curtail energy consumption, resulting in substantial cost savings and a diminished carbon footprint. Moreover, the integration of renewable energy technologies empowers the localized generation of electricity, ensuring a reliable and sustainable energy source. Noteworthy in this study is the novel linkage of energy usage indicators to the comfort levels experienced in university settings during both summer and winter. An exhaustive examination of consumption indicators, rooted in the diverse activities on college campuses, further enriches the investigation. Beyond technical intricacies, this study scrutinizes the economic viability, environmental advantages, and educational significance of these integrated systems. Embracing EERES not only aligns with the commitment of educational institutions to environmental stewardship but also establishes a paradigm for broader communities. These institutions aspire to exemplify sustainable practices, influencing larger societal behavior positively. Various factors, including the institution’s type, energy source, facility nature, building construction, internal activities, weather conditions, and user behavior, wield substantial influence over energy utilization. This study offers a nuanced exploration, shedding light not only on the technical dimensions but also on the broader economic, environmental, and educational implications of adopting EERES.

The impact of using an IoT-based automatic solar panel cleaner on building energy performance

Abstract Solar energy is a great provider of renewable environmentally friendly energy. Thanks to solar technologies, it converts sunlight into electrical energy using multiple devices such as photovoltaic cells. The generated electrical energy can be used for multiple purposes such as commercial, industrial, and domestic uses. Generating electrical energy without releasing toxic gases is considered one of the biggest advantages of using solar energy. While solar panels are a reliable source of clean electrical energy, their power output can be decreased due to the lack of maintenance and especially cleaning. The efficiency of solar panels decreases by more than 40% due to the lack of cleaning. That is why routine cleaning is crucial to ensure the optimum performance of them. Providing an automatic solar panel cleaning system will ensure that routine maintenance is done and the electricity output is optimum. Integrating the use of photovoltaic cells in buildings helps improve the energy performance and energy efficiency of buildings. This research paper aims to determine the impact of integrating an internet of things (IoT)-based automatic solar panel cleaner and measure the energy efficiency of using it. The IoT-based automatic solar panel cleaner contributed to raising the solar panel power wattage by 89.33% in a hot desert climatic region.

Economic Viability of Bamboo Dust Based Gasification Plant for a Paper Mill

Global concern over pollution and several related issues caused by increase in Green House Gas emission and consequently changes in climate have resulted in a paradigm shift in the approach towards development of the energy sector in many countries. Being relatively less expensive than other renewable sources like solar and wind energy and being geographically dispersed, biomass is a potential alternative for fossil fuels like coal to sustainably meet the increasing energy needs of the world. In addition to this, biomass is carbon dioxide neutral and is a reliable source of energy. In this paper a pilot project is conceptualized on the use of bamboo dust waste for Cachar Paper Mill located in the state of Assam, India. This paper mill is a source of biomass in itself as it generates about 35-40 tons of bamboo dust every day. This project is conceived to economically generate electricity by utilizing producer gas derived from a gasifier by means of a gas engine coupled with an alternator, thus contributing its share towards renewable energy in the country. An economic viability study has been carried out by calculating the cost of generation of electricity for the plant to produce this green energy as against that of convention coal fired stream generation. This paper further highlights how burning of reasonable quantity of coal can be avoided by replacing some quantum of electricity generation through renewable energy sources resulting in appreciable amount of cost savings.

Depth estimation for geothermal reconnaissance deduced from aeromagnetic data over the Mambilla plateau and environs, Taraba State, Northeastern Nigeria

The geothermal gradient, heat flow and Curie point depth (CPD) were calculated using aeromagnetic data to assess their viability in terms of energy generation around Mambilla plateau and environ, Northeast, Nigeria. Each block of spectral plot was used to determine the depths to the top boundary (Zt), to bottom (Zb) and centroid (Zo). Empirical formula was used to calculate the geothermal gradient, Curie Point Depth (CPD) and heat flow in the area. The resulting depth measurements were then consider as the area's geothermal gradient, heat flow, and curie point depths (CPD). Two CPD locations with geothermal potential are described in the results: areas with shallow curie point depths (0.11-1.72 km) and areas with deeper curie point depths (0.34-4.46 km). The geothermal gradients measured range from 46.22 to 121.620oCkm-1, while the measured heat-flow values range from 139.16 to 304.05 mWm-2 . This study also reveals how complex magmatic and tectonic linkages of large intrusions and fault systems, particularly the Chain faults that may have extended into the study area, are related to geothermal systems. A common CPD of 3oC100m-1 or 30oCKm-1 and average thermal conductivity values ranging from 105.68 to 227.63mWm-2 are considered to have a good potential for geothermal energy. This result have strong and positive correlation with what is obtained in some countries were geothermal energy is been utilized for power generation. The potential for geothermal energy resources in the area is therefore very high. The study's most important and practical finding is that the area has good potentials for geothermal energy resources, which could be used to compliment the Government-owned Mambilla Hydro-Electric Power Plant, as a reliable renewable energy source.

Negligible radiological impact of Indian nuclear power plants on the environment and the public: Findings from a 20-year study

Nuclear power plants, recognized for their extended operational life, minimal greenhouse gas emissions, and high-power density, are deemed as reliable energy sources. Nonetheless, concerns persist regarding the radioactive discharges from these plants and their potential impact on health and the environment. To comprehend the radiological implications of such releases, this study presents, for the first time, an analysis of radiological data from 7 Indian nuclear power plants (NPPs), collected by Indian environmental survey laboratories (ESL) over the past two decades (2000-2020). This dataset encompasses radioactivity concentrations in the atmospheric, aquatic, and terrestrial environments within a 30 km radius of each NPP, as well as the annual cumulative external gamma doses recorded by environmental thermoluminescence dosimeters (TLDs). The analysis yielded several key findings: (i) Radioactivity concentrations around the NPPs were low and comparable to values measured at other nuclear power plant sites worldwide; (ii) Tritium concentrations in receiving water bodies were <1 % of the internationally recommended limit of 10,000 Bq/l; (iii) The estimated total radiation doses to the public were at most 10 % of the stipulated regulatory dose limit of 1000 μSv and consistently decreased over the study period and (iv) Variations in doses among the NPP sites were primarily attributed to legacy technology used in specific reactors. These results indicate efficient and secure reactor operations and the minimal contribution of Indian nuclear power plants to anthropogenic doses in the country. The findings hold potential significance for reinforcing India's commitment to advancing its nuclear power program.

Design guidelines for HAWT / VAWT decision-making in the context of underserved communities

Underserved communities in rural areas often lack access to appropriate technologies that provide sustainable and reliable energy sources vital to their well-being and economic activities. In this context, the potential of small-scale wind turbine generators (WTGs) as a renewable energy source is investigated, as they can provide enough energy while being relatively easy to operate and maintain. Nevertheless, limited research is carried out about the comparative advantages of vertical axis wind turbines (VAWTs) and horizontal axis wind turbines (HAWTs) for these resource-limited conditions. The research approach includes a literature review, a field study in Kenya, and a multi-criteria decision analysis (MCDA) tailored to local wind conditions and humanitarian engineering design principles. Structural, operational, and performance differences between HAWTs and VAWTs are explored as well as the local needs of underserved communities. The MCDA results highlight design principles for the deployment of small wind turbines in rural areas and provide useful design guidelines for WTG development in underserved regions.

Re-Approaching EU’s Energy Policy: The Vital Role of Nuclear Power

The energy cut-down that followed the Russo-Ukrainian war is the main cause of the recent skyrocketing gas prices, which are jeopardizing the stability of the EU’s internal energy market. Hence, the diversification of energy sources has become a major priority. In this context, nuclear power must be reconsidered as a reliable alternative energy source which can lead to the partial independence of the EU. The upper goal of energy security can only be achieved if the EU relies on an energy source, such as nuclear, that ensures availability, reliability, affordability, and sustainability – all, at once. This policy brief outlines the importance of nuclear energy as a key factor for the EU’s energy future and proposes measures that can be implemented to achieve a nuclear and green transition.

Future electricity production at Mutriku Wave Energy Plant estimated from CMIP6 wave climate projections (2015–2100)

Renewable marine energy sources are rapidly developing worldwide. With numerous operational marine power plants in existence, it is becoming increasingly important to explore their potential. Hence, this study aims to examine the impact of climate change on the future potential of wave energy. The case study was centred on the Mutriku Wave Energy Plant, situated in the Bay of Biscay in the northern region of the Iberian Peninsula.To accomplish this, this study investigated changes in wave energy from 2015 to 2100 by employing ERA5 data and an ensemble of CSIRO wave projections driven by six distinct models derived from CMIP6 model runs. Two were associated with the SSP1-2.6 pathway while the other four corresponded to the SSP5-8.5 pathway. The unidimensional wave variables were bias-corrected using the Quantile Matching (QM) technique, whereas the bidimensional variables were corrected using the Multivariate Bias Correction N-pdf (MBC N-pdf) technique. Subsequently, a self-organising map (SOM) technique was employed to classify daily sea type frequencies and power. Additionally, the Smirnov test was employed to determine whether the probability density functions derived from different datasets exhibited significant differences at a significance level of 0.05.The conclusions obtained indicate that energy production in the Bay of Biscay will remain stable in the late 21st Century. The daily frequencies of the sea type and power did not change significantly. This stability ensures consistent power generation, enabling the location to provide a reliable and consistent source of energy both currently and in the future.

Effect of the X-grid static mixer flow inserts on the performance of parabolic trough collector

Solar energy is a very convenient and reliable renewable energy source to fulfill our society's wide variety of energy requirements. Solar concentrator-based energy technologies are the best way to utilize solar energy nowadays. Among those technologies, PTC (Parabolic Trough Collector) is a well-mature and reliable concentrating solar power technology having various real-world applications with solar standalone as well as in hybrid modes. For improving the performance of PTC, flow inserts are a very promising technique. This work aims to investigate the X-grid static mixer flow inserts on the performance of the PTC module. Here, X-grid static mixer flow inserts are modeled and compared with the simple cylindrical tube without any inserts inside by using a validated model in Ansys Fluent 18.1. Evaluation criteria include flow analysis, overall efficiency, exergy efficiency and thermal efficiency. The overall efficiency and exergy efficiency are the most prominent factors for the evaluation of PTC performance. The PTC is analyzed with various inlet fluid temperatures ranging from 303 K to 653 K with a variation in the volumetric flow rate ranging from 50 LPM (Litre Per Minute) to 250 LPM. The enhancement in the thermal performance of PTC using an X-grid static mixer is more as the inlet fluid temperature increases. The pressure drop increases multiple times with the use of X-grid flow inserts, but the overall rise of pump work is low. Overall thermal efficiency is higher for the X-grid static mixer than the plain tube which is mainly used in the PTC. The presented investigation results can be helpful for the design of X-grid static mixer.