Clean Energy Systems Research Articles

Denitration Simulation of SNCR System Nozzles at Different Layout Positions in Coal Powder Boilers

Building a clean, low-carbon, safe and efficient energy system is an overall requirement for the modernization of the energy system, The nitrogen oxides produced by the combustion of fossil fuels need to be effectively treated. The selective non-catalytic reduction denitrification (SNCR) technology in the thermal power industry. It is widely used due to its low cost and mature technology. By using CFD software to simulate and study the coupling of flue gas temperature field and NO concentration field, the SNCR nozzle was set up to study the impact on denitrification efficiency. Simulate multiple layout methods, including sequential arrangement, staggered arrangement, concentrated in the middle and concentrated on both sides. The denitrification efficiency is highest among them, which is concentrated on both sides and further optimized through the NO concentration field in the furnace. After optimization, the denitrification efficiency reached 59.2%, which was 2.4% higher than the traditional uniform layout method. It has important practical guidance significance for energy conservation, emission reduction, and operational optimization.

A high-performance electrocatalyst via graphitic carbon nitride nanosheet-decorated bimetallic phosphide for alkaline water electrolysis.

Developing renewable and clean energy systems for overall water electrolysis requires low-cost, highly efficient, and stable catalysts. With this motivation, nickel cobalt phosphorus (NiCoP) was electrodeposited onto nickel foam (NF) and then modified with graphitic carbon nitride (g-C3N4). The designed g-C3N4/NiCoP/NF electrode was used for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline water electrolysis. It exhibited a small overpotential of 80 mV@10 mA cm-2 with a Tafel slope of 89 mV dec-1 for the HER. It also exhibited an overpotential of 370 mV@10 mA cm-2 with a Tafel slope of 64 mV dec-1 for the OER. The g-C3N4/NiCoP catalyst exhibited satisfactory stability in an alkaline electrolyzer system, in which g-C3N4/NiCoP/NF was used as the anode and cathode. Meanwhile, the electrocatalyst requires only a cell voltage of 1.70 V to achieve 10 mA cm-2 current density for overall water electrolysis.

Photovoltaics Efficiency on Automatic Fish Feeding Distributors Device Using Internet of Things

Renewable energy is crucial for facilitating the shift towards a more sustainable society. It plays a significant role in establishing a clean energy system, mitigating greenhouse gas emissions, and enhancing the well-being of both current and future generations. The study included field observation and data analysis approaches. The study utilized IoT-based automatic fish feed spreaders, photovoltaic units, batteries, SCC (solar charge controller), Android phones, thermometers, multimeter tester, LCDs, ultrasonic sensors, and a microcontroller circuit. This study aims to acquire power, electrical energy, and efficiency measurements from solar systems employed in an Internet of Things (IoT) enabled automatic fish feeder apparatus. The results show that the power consumption needed to operate the IoT-based automatic fish feeder gadget is 48.75 watts. The peak of solar irradiance was recorded at 12.00 WIT, averaging 900.27 W/m2. The lowest intensity was at 09.00 WIT, averaging 422.78 W/m2. Photovoltaics can produce electrical power at 22.75 watts per hour, leading to a daily electrical energy output of 159.25 Wh. The highest photovoltaics efficiency was 16.37% with 465.3 W/m2 of solar irradiance, 30.7°C of temperature and 2.144 m/s of wind speed. The temperature and wind speed has significantly affected on photovoltaics efficiency.

Facile hydrothermal synthesis of NiMoO4·xH2O nanorods-like structures as bifunctional oxygen electrocatalysts for rechargeable zinc-air batteries

Developing highly active and low-cost bifunctional catalyst materials to replace precious metal species is of utmost importance for the commercialization of clean and sustainable energy systems. In this report, homogenous NiMoO4·xH2O nanorods (NRs)-like structured materials were synthesized by an annealing-free hydrothermal method. The synthesized electrode electrochemical properties were determined by linear sweep voltammetry using a rotating ring disk electrode to determine the characteristics of oxygen reduction reaction in an O2-saturated electrolyte solution. For the oxygen evolution reaction, the NiMoO4·xH2O NRs electrocatalyst showed lower overpotential of 185 mV to obtain 10 mA cm−2. Furthermore, the NiMoO4·xH2O NRs electrocatalyst-based zinc (Zn)-air battery exhibited lower voltage gaps and smaller electrochemical impedance spectroscopy values than the Pt/C catalyst. Importantly, the NiMoO4·xH2O NRs-based battery (60 cycles (∼1100 min)) revealed excellent cycling stability results when compared with the Pt/C-based battery (30 cycles (∼550 min)). The NR structured electrode provided good steady potential after being subjected to a fixed current density of 10 mA cm−2 for 100 h. Therefore, these results demonstrate that the synthesized NiMoO4·xH2O NRs material is promising as a bifunctional electrocatalyst for rechargeable Zn-air batteries.

Techno-economic feasibility of stand-alone hybrid energy system with battery storage in educational buildings: A case study of Uttara University

Stand-alone hybrid energy systems (HES) have the potential to significantly reduce pollutant emissions and alleviate strain on the national grid. The selection and sizing of stand-alone HES for buildings can serve as a methodological approach toward establishing a resilient and clean electrical energy system in urban areas of developing countries. To explore this further, a case study was conducted using Hybrid Optimization of Multiple Energy Resources (HOMER) to assess the feasibility of implementing a HES at Uttara University in Dhaka, Bangladesh. This study examined the technical, economic, environmental, social, and reliability aspects of a stand-alone HES. The findings of this study suggested that the PV-WT-DG-BT is the most cost-effective solution for the University when compared to other hybrid configurations. Additionally, this HES benefits the surrounding communities by creating employment opportunities and contributing to human development. The sensitivity analysis showed that the COE and NPC of the optimal HES are sensitive to fuel price changes. A PV slope angle of 23.88° was cost-effective, and a 20-meter wind turbine hub height was optimal. It was observed that increased solar radiation decreases COE. Further, sensitivity analysis showed that fuel costs, CO2 emissions, and NPC will decrease if average daily load demand declines. It was also found that 1 kWh of Li-Ion-based HES performed the best compared to other batteries. Finally, the results of the genetic algorithm (GA), and grey wolf optimizer (GWO) showed that they provide the same optimum configuration as HOMER but with the lowest NPC. The findings of this study can serve as a foundational model for designing HESs in other large educational buildings located in low and middle-income countries with environmental conditions and socio-economic characteristics similar to Bangladesh.

Electrochemical Preparation and Characterization of Gold Coatings on Stainless Steel Bipolar Plates for Corrosion Protection in PEM Electrolyzers

With the increasing demand for CO2 reduction in all industrial sectors, the utilization of renewable energy and a sustainable storage structure plays an essential role to reach a clean energy system. Hydrogen is one of the important elements which can be used as an energy carrier due to its high specific energy density (ca. 40 kWh/kg) and also as a reducing agent in steel production to greatly lower CO2 emissions. Currently, hydrogen is mainly produced via steam reforming of natural gas which produces large amounts of CO2 gas. This can be replaced by a much cleaner process of water electrolysis using a PEM (Proton Exchange Membrane) electrolyzer. The projected high demand for PEM electrolyzer stacks urges an industrial scaled-up manufacturing process of the electrolyzer’s components such as the bipolar plates (BPP) and porous transport layers (PTL). To reduce the production costs, an inexpensive base material like stainless steel can be utilized but needs a stable, conductive, and protective thin coating to withstand the highly acidic conditions during electrolysis at the anode.This contribution will discuss recent results on applying a noble metal coating (e. g. Au) to increase surface conductivity and to protect the stainless steel BPP from corrosion. Several electrochemical deposition methods including the pretreatments were investigated to ensure a stable and homogenous coating. Different layer combinations with Ni as an adhesive layer were also tested and compared for their corrosion stability. So far, a single-layer Au coating showed good performance as a protective coating.

Time-dependent structural tuning of in-situ-grown MnCo2O4 nanostructures on Ni-foam for efficient overall water splitting

The development of highly efficient, stable, and cost-effective electrocatalysts for overall water splitting (OWS) is necessary for future renewable and clean energy systems. In this study, MnCo nanostructures were directly grown on Ni foam by a one-step hydrothermal synthesis method for various reaction times, such as 3, 6, 12, and 24 h, and the synthesized samples are denoted as MnCo-3,11MnCo-3 – The MnCo2O4 samples calcined at 400 °C for 3h. MnCo-6,22MnCo-6 – The MnCo2O4 samples calcined at 400 °C for 6h. MnCo-12,33MnCo-12 – The MnCo2O4 samples calcined at 400 °C for 12h. and MnCo-24,44MnCo-24 – The MnCo2O4 samples calcined at 400 °C for 24h. respectively. The scanning electron microscopy (SEM) images confirm the influence of the reaction time on the morphology of the MnCo nanostructures. The synthesized electrocatalysts reveal good catalytic activity for hydrogen evolution reaction (HER) as well as oxygen evolution reaction (OER) in 1.0 M KOH. The MnCo-24 electrocatalyst outperformed the other prepared electrocatalysts, with Tafel slopes of 140 and 148 mV dec−1 and low overpotentials of 200 and 178 mV for the OER and HER, respectively, at a current density of 10 mA cm−2. The MnCo-24 electrocatalyst exhibited excellent stability for up to 24 h for OWS. This work provides a facile strategy for preparing low-priced electrocatalysts with high catalytic activity.

Exploring properties of organometallic double perovskite (CH3NH3)2AgInCl6: A novel material for energy conversion devices

Distinct types of materials are being explored for usage in thermoelectric (TE) and photovoltaic (PV) systems in order to alleviate the energy problem. In order to create nontoxic, more stable, and best-performance energy convergence devices, the state-of-the-art hybrid halide double perovskites (HHDPs) compound has been identified as a potential TE material and potential replacement for hazardous lead. We have proposed a new HHDP material (CH3NH[Formula: see text]AgInCl6 and performed its theoretical investigation via the full potential linear augmented plane wave (FP-LAPW) method. The computational results show that the studied compound exhibits a direct bandgap of 3.708[Formula: see text]eV and has exceptional PV characteristics in the ultraviolet (UV) region. The obtained thermodynamic (TD) characteristics confirm that the titled compound is thermally stable at various temperatures and pressures. At 300 K, the examined HHDP material has the highest ZT (=2.23) in the p-region. Materials with higher ZTe values are substantially more important for generating electrical energy through waste heat. The ZTe result validates the use of these materials in TE devices at ambient temperature. The parameters of this compound have been computed for the first time. This study identifies (CH3NH[Formula: see text]AgInCl6 as a novel HHDP compound. Through an in-depth exploration of its properties, this study offers valuable insight for further research with potential applications in clean energy systems.

Research on Hydrogen Production System Technology Based on Photovoltaic-Photothermal Coupling Electrolyzer

Solar hydrogen production technology is a key technology for building a clean, low-carbon, safe, and efficient energy system. At present, the intermittency and volatility of renewable energy have caused a lot of “wind and light”. By combining renewable energy with electrolytic water technology to produce high-purity hydrogen and oxygen, which can be converted into electricity, the utilization rate of renewable energy can be effectively improved, while helping to improve the solar hydrogen production system. This paper summarizes and analyzes the research status and development direction of solar hydrogen production technology from three aspects. Energy supply mode: the role of solar PV systems and PT systems in this technology is analyzed. System control: the key technology and system structure of different types of electrolytic cells are introduced in detail. System economy: the economy and improvement measures of electrolytic cells are analyzed from the perspectives of cost, consumption, efficiency, and durability. Finally, the development prospects of solar hydrogen production systems in China are summarized and anticipated. This article reviews the current research status of photovoltaic-photothermal coupled electrolysis cell systems, fills the current research gap, and provides theoretical reference for the further development of solar hydrogen production systems.

Review of Hot Topics in the Sustainable Development of Energy, Water, and Environment Systems Conference in 2022

The current applications in the energy sector are based largely on fossil fuels which release greenhouse gas emissions to the atmosphere. To face the issue of global warming, the energy sector has to transfer to and develop sustainable energy solutions that do not release carbon emissions. This is one of the primary motivators for the SDEWES conference as well as for this review, and previous ones, examining the most recent works based on sustainable and green energy production in such fields. The 17th Conference on the Sustainable Development of Energy, Water, and Environment Systems (SDEWES) was held on 6–10 November 2022 in Paphos, Cyprus. The SDEWES conference aims at solving complex and ongoing concerns that approach a long-term perspective and supporting innovative solutions and continuous monitoring and evaluation. This review paper aims at collecting the main presented papers focused on the following hot topics: low-carbon technologies based on renewable and clean-energy systems, including mainly biomass, solar, and wind energy applications; energy storage systems; hydrogen-based systems; energy-saving strategies in buildings; and the adoption of smart management strategies using renewable energy systems. These topics are investigated in order to propose solutions to address the issues of climate change, water scarcity, and energy saving. From the analyzed works, we note that some key issues for sustainable development remain to be further addressed: such as novel and advanced energy storage systems, green hydrogen production, novel low-temperature district heating and cooling networks, novel solar technologies for the simultaneous production of power and high temperature heat, solar desalination for hydrogen production systems, and agrivoltaic systems for the production of power and food.

Special Issue: “The Future of Nuclear Power for Clean Energy Systems”

Currently, many countries are considering the construction of nuclear power plants as a result of rapidly changing global political and economic conditions [...]

Performance of Solar-based Electrochemical System as Post-treatment of Hospital Wastewater Contaminated with Ciprofloxacin

T his research evaluated performance of a solar-based electrochemical system as a post-treatment of hospital wastewater contaminated with Ciprofloxacin (CIP), an antibiotic drug. Two laboratory-scale electrochemical units, and consisting of 2-5 anode and 1-4 cathode plates, were employed. Two types of electrode plates, aluminum (Al) and stainless steel (Ss), were installed in the units and their treatment efficiencies were investigated. Optimum conditions of the electrochemical system were determined by using a synthetic wastewater containing 0.01-20 mg/L of CIP (batch system); these experimental results were validated by using an actual hospital wastewater and a solar-based electrochemical system (continuous system). The experimental results of the batch system showed that the maximum CIP removal of 69% could be achieved at 10 minutes of hydraulic retention time (HRT), 18 volts in a voltage of power source (VPS), 83 A/m2 of current density (CD), and 1 cm of inter-electrode distance (IED) on Al plates. Similar results in the continuous system were obtained when the electrochemical system was fed with hospital wastewater containing CIP of about 350 ng/L. Application of solar-based energy in the electrochemical system showed similar efficiency of CIP removal, suggesting the applicability of the clean energy system for post-treatment of hospital wastewater containing antibiotic drugs

A Comprehensive Evaluation Method for Planning and Design of Self-Sufficient Wind Power Energy Systems at Ports

This study proposes a scientific method to assess the rationality of planning and design of self-sufficient wind power systems (SS-WPSs) at ports. The evaluation method proposed is based on the concept of integrated development of water transportation and a clean energy system, taking into account the demand of the former and the availability of the latter. First, the factors representing the property of the system from the perspectives of economy, environment, energy efficiency, self-sufficiency, and reliability are calculated. The evaluation method is developed by using a combined Analytical Hierarchy Process and Entropy Weight Method (AHP-EWM) to calculate the subjective and objective weights of these factors. Subsequently, a combined weighting method based on game theory is employed with the aim of minimizing deviations between the subjective and objective weights and the combination weights, thereby determining the optimal combination of weights of the evaluation factors. These weights will be used to calculate evaluation results under different planning schemes. To validate the effectiveness of the method, a case study is developed based on a wind power energy demonstration project at a dock of a container port. Study results reveal that Option C, considered in this study, outperforms other options with the highest evaluation score of 0.737. Sensitivity analysis further underscores the reliability of Option C, showing a robust 96.15% probability of achieving the maximum final score within a 20% variation range. This indicates that the case study demonstrates that intuitive and realistic evaluation results can be obtained from the proposed method. These results affirm the practicality of our approach, providing invaluable insights for planners, policymakers, and stakeholders involved in sustainable energy initiatives.

Secure Hydrogen Production Analysis and Prediction Based on Blockchain Service Framework for Intelligent Power Management System

The rapid adoption of hydrogen as an eco-friendly energy source has necessitated the development of intelligent power management systems capable of efficiently utilizing hydrogen resources. However, guaranteeing the security and integrity of hydrogen-related data has become a significant challenge. This paper proposes a pioneering approach to ensure secure hydrogen data analysis by integrating blockchain technology, enhancing trust, transparency, and privacy in handling hydrogen-related information. Combining blockchain with intelligent power management systems makes the efficient utilization of hydrogen resources feasible. Using smart contracts and distributed ledger technology facilitates secure data analysis (SDA), real-time monitoring, prediction, and optimization of hydrogen-based power systems. The effectiveness and performance of the proposed approach are demonstrated through comprehensive case studies and simulations. Notably, our prediction models, including ABiLSTM, ALSTM, and ARNN, consistently delivered high accuracy with MAE values of approximately 0.154, 0.151, and 0.151, respectively, enhancing the security and efficiency of hydrogen consumption forecasts. The blockchain-based solution offers enhanced security, integrity, and privacy for hydrogen data analysis, thus advancing clean and sustainable energy systems. Additionally, the research identifies existing challenges and outlines future directions for further enhancing the proposed system. This study adds to the growing body of research on blockchain applications in the energy sector, specifically on secure hydrogen data analysis and intelligent power management systems.

Mo-doped one-dimensional needle-like Ni3S2 as bifunctional electrocatalyst for efficient alkaline hydrogen evolution and overall-water-splitting

Hydrogen energy plays an important role in clean energy system and is considered the core energy source for future technological development owing to its lightweight nature, high calorific value, and clean combustion products. The electrocatalytic conversion of water into hydrogen is considered a highly promising method. An electrocatalyst is indispensable in the electrocatalytic process, and finding an efficient electrocatalyst is essential. However, the current commercial electrocatalysts (such as Pt/C and Ru) are expensive; therefore, there is a need to find an inexpensive and efficient electrocatalyst with high stability, corrosion resistance, and high electrocatalytic efficiency. In this study, we developed a cost-effective bifunctional electrocatalyst by incorporating molybdenum into nickel sulfide (Ni3S2) and subsequently tailoring its structure to achieve a one-dimensional (1D) needle-like configuration. The hydrogen production efficiency of nickel sulfide was improved by changing the ratio of Mo doping. By analyzing the electrochemical performance of different Mo-doped catalysts, we found that the Ni3S2-Mo-0.1 electrocatalyst exhibited the best electrocatalytic effect in 1 M KOH; at a current density of 10 mA cm−2, it exhibited overpotentials of 120 and 279 mV for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), respectively; at a higher current density of 100 mA cm−2, the HER and OER overpotentials were 396 and 495 mV, respectively. Furthermore, this electrocatalyst can be used in a two-electrode water-splitting system. Finally, we thoroughly investigated the mechanism of the overall water splitting of this electrocatalyst, providing valuable insights for future hydrogen production via overall-water-splitting.

Recent Progress in the Use of Perovskites for Electrochemical, Photoelectrochemical, and Photovoltaic–Electrochemical CO2 Reduction

Developing novel functional materials to advance the technological level of clean and renewable energy systems is the focus of much research. Due to their outstanding operational and compositional properties, perovskite-based structures have already been studied as an important class of solid-state components for electrochemical (EC), photoelectrochemical (PEC), and photovoltaic–electrochemical (PV-EC) CO2 reduction, showing great potential in their catalytic activity and device stability and with a promising window for further technological developments. In this review, the different kinds of perovskites in the context of their structural features, which lead to their different applications, are first investigated. Then, we summarize the recent progress in the use of perovskites in EC, PEC, and PV-EC CO2-reduction devices. The research demonstrates that the mechanism and kinetics of intermediate formation have a significant effect on the creation of the final product. Investigations show that appropriate surface modifications, such as through the use of doping agents, alloy construction, and composites, can considerably improve the electrocatalytic activity and stability of perovskites. Finally, the perspectives on, and limitations of, the commercial and large-scale production of perovskites for CO2 reduction are stated.

Assessing the Potential of Artificial Intelligence in Advancing Clean Energy Technologies in Europe: A Systematic Review

This systematic review investigates the role of artificial intelligence (AI) in advancing clean energy technologies within Europe, based on a literature survey from 2006 to 2023. The assessment reveals that AI, particularly through deep learning and neural networks, enhances the efficiency, optimization, and management of clean energy systems. Noteworthy is AI’s capacity to improve short-term energy forecasts, essential for smart cities and IoT applications. Our findings indicate that AI drives innovation in renewable energy, contributing to the development of smart grids and enabling collaborative energy-sharing models. While the research underscores AI’s substantial influence in Europe’s energy sector, it also identifies gaps, such as varied AI algorithm applications in different renewable energy sectors. The study emphasizes the need for integrating AI with emerging clean energy innovations, advocating for interdisciplinary research to navigate the socio-economic, environmental, and policy dimensions. This approach is crucial for guiding a sustainable and balanced advancement in the clean energy landscape, signifying AI’s pivotal role in Europe’s energy transition.

Transition to a new kind of energy: carbon emission capture using nanotechnology

At a time when the consequences of carbon emissions are becoming increasingly apparent, the world is looking for alternative energy sources to reduce its dependence on fossil fuels and combat climate change. One of the most promising frontiers in the search for sustainable energy is hydrogen. Often regarded as the “fuel of the future”, hydrogen is an important solution to both our energy needs and curbing carbon emissions. As we stand at the crossroads of environmental sustainability, this article begins a journey into the world of hydrogen energy. This article examines the transition to new generation energy sources and the potential of this transition to reduce carbon emissions. We explore the wonders of hydrogen as a clean and versatile energy carrier, and methods of carbon capture. In addition, this article will highlight efforts to control carbon emissions and discuss how innovative approaches such as carbon capture and storage (CCS) technologies can be used. This can play an important role in achieving carbon emission reduction targets. In conclusion, this article will help you understand why this significant change in the energy sector is needed, how it is happening, and why it is so important for controlling carbon emissions. It serves as an introduction to our journey to reduce carbon emissions and open the door to a cleaner, more sustainable and greener energy system in the future.

Evaluation of a novel coupling process for the simultaneous production of syngas and ultra-pure hydrogen from natural gas with in situ utilization of carbon dioxide

Recently, with the aim of developing clean and efficient energy systems, various designs based on chemical looping combustion and reforming have been suggested. This study proposed and investigated the production of ultra-pure hydrogen in dual-purpose integrated zero-emission reforming (UPH2-DPIZER) process based on the sorption-enhanced chemical looping steam methane reforming (SECLSMR). This process is proposed on the basis of reduction in the emissions of carbon dioxide as well as the simultaneous generation of pure hydrogen and syngas for use in a wide range of applications. One of the most novel aspects of this research is that the proposed UPH2-DPIZER process can reduce or eliminate carbon dioxide emissions because all the produced and chemisorbed CO2 can be applied directly in the reforming process without any additional purification. Furthermore, the synthesized 30 wt%NiO-5wt.%CeO2/Al2O3 oxygen carrier was examined using the X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS) and scanning electron microscopy (SEM) techniques along with evaluation in SECLSMR process. The attained results of experimental tests are applied to adapt and validate the simulations of novel proposed process. The other objectives of this study are the reduction in required energy for the whole process along with reduction in the direct consumption of fossil fuels. The experiments showed high H2/CO molar ratio of 36 at 550 °C with appropriate methane conversion of about 74 %, while at 750 °C, nearly a complete conversion of CH4 occurs. The obtained results from the simulation of proposed UPH2-DPIZER showed the production of ultra-pure hydrogen along with syngas with H2/CO molar ratio of about 1 with negligible CO2 release.

Hydrogen storage on the lithium and sodium-decorated inorganic graphenylene

Efficient H2 storage is one of the keys to the energy transition toward global sustainability. Hydrogen energy sources on functionalized 2D materials by metals have been shown as promising alternatives for clean energy systems. In a particular way, we have demonstrated here that the inorganic graphenylene-like silicon carbide (IGP-SiC) weakly adsorbs H2. At the same time, the Li/Na decoration significantly enhances the H2 interaction, accommodating up to 48H2 molecules by a stronger physisorption. Also, scanning bond critical points (BCPs) confirms a great interaction between the Li(Na)@IGP-SiC systems and the hydrogen, a distinct scenario for the pristine IGP-SiC. Gravimetrically, hydrogen densities reach 8.27 wt% (Li) and 6.78 wt% (Na), exceeding the U.S. Department of Energy (5.6 wt%) benchmark. Regarding thermodynamic stability, the desorption temperatures at ambient conditions are suitable for hydrogen storage devices. Therefore, Li(Na)@IGP-SiC systems emerge as high-capacity hydrogen storage materials.