Sweeka Meshram, Ganga Agnihotri, Sushma Gupta

Journal of Renewable and Sustainable Energy • 2014

<jats:p>This paper presents modeling and simulation of the advanced photovoltaic (PV)/hydro based Hybrid Renewable Energy System (HRES) to electrify such isolated/remote areas, where grid accessibility is not possible. For 7.5 kW hydro generation system, a Self Excited Induction Generator (SEIG) with improved technique is used to optimize the utilization of hydro power. To achieve this aim, an uncontrolled bridge rectifier coupled with Hydro side Voltage Source Inverter is implemented for the SEIG based advanced hydro system. The PV system is configured by PV array, battery, DC/DC converter, maximum power point tracking controller, and PV side Voltage Source Inverter. A Constant Current Control scheme is developed in this paper to control active and reactive power flow and to synchronize hydro and PV systems. The proposed system uses fewer controlled switches, hence complexity of control has been reduced and system has higher efficiency and lower switching losses. The performance analysis of the HRES has been done to authenticate the existence of the system using the MATLAB software and results demonstrate that power quality of the proposed system is better and HRES is able to put into services.</jats:p>

Tomoki Taniguchi, Shigesuke Ishida, Yoshimasa Minami

Volume 8: Ocean Renewable Energy • 2013

<jats:p>This paper addressed assessing feasibility of hybrid use of ocean renewable energy, such as wave and wind energy around Japanese coast. At first, wave and wind energy theoretical potentials were calculated and, in the second step, correlation coefficient between wave and wind energy was computed around Japanese coast. Sea area suitable for hybrid use of ocean renewable energy resources is supposed to have high potential for some types of energy resources. Furthermore, correlation of power generation between wave and wind energy resources should be low because one energy resource needs to complement another one for stabilizing power generation.</jats:p> <jats:p>Based on the assumptions, feasibility of wind and wave energy was evaluated on some sea areas where R&amp;D project are ongoing.</jats:p>

Ambati SANDEEP, K. ARCHANA, Sivakumar ELLAPPAN et al.

Journal of Thermal Engineering • 0

<jats:p xml:lang="en">Metal nitride multilayer films display a unique combination of exceptional properties with respect to optical absorption, thermal emission, corrosion resistance, adhesion between coating and surface and high temperature withstand. Most considerable aspects of nitride coatings were economical, environmentally friendly and easy to develop. Similar to nitride thin films, to achieve a considerable absorption (α) -0.92 and low emission (Є) -0.08 along with chemical and radiation stable solar selective coatings, Diamond Like Carbon (DLC) thin films exhibit the desirable properties for Concentrated Solar thermal Power(CSP)applications. The main advantages of DLC films were high hardness, chemical and radiation stability and good control over the optical properties. To achieve above-mentioned properties, optimization of each layer of the DLC coating has needed. The main aim of this research is optimization of Cr-base layer using Cr-Target current 175A to get 125 nm thicknesses, optimise the AlSiN absorber layer by controlling the AlSi- target current 175A to maintain 35nm thickness. The sequence of the DLC coating layers was selected based on their relative thickness, which was optimize to get good solar selectivity (α/Є). Individual layers of the DLC solar coatings have unique properties to get overall required high absorbance and low emission along with chemical and radiation stability. These solar selective multi-layers (Cr/DLC/AlSiN) have deposited by using available Cathodic targets (Cr , AlSi &amp; Ti) in Cathodic Arc Physical Vapor Deposition (CAPVD) and optimized parameters were mainly depend on the target currents to control over the thickness of the each layer, base pressure 1*10-5 mbar and deposition temperature 400°C. The DLC multilayer solar selective coatings were characterized using Ultraviolet Visible Near infrared (UV- Vis- NIR) spectrophotometer, Scanning Electronic Microscopy (SEM), Transmission Electron Microscopy (TEM) and Raman spectroscopy etc. Scratch test and corrosion tests have conducted for these absorber coatings testing.</jats:p>

Nitin Dattatray Nikam

Solar Thermal Technologies and Nano-Enhanced Phase Change Materials for High-Efficiency Electric and Solar Mobility • 2025

<jats:p>The rapid evolution of solar energy technologies necessitates equally advanced solutions for efficient thermal energy storage (TES). Nano-enhanced phase change materials (NePCMs) have emerged as a promising class of materials capable of significantly improving thermal conductivity, energy density, and phase stability in TES systems. The realizing their full potential demands intelligent control, adaptability, and real-time responsiveness to environmental and operational dynamics. This chapter presents a comprehensive framework that integrates algorithmic intelligence with NePCM-based TES to achieve highly efficient, self-regulating thermal storage solutions for solar energy applications. The incorporation of artificial intelligence (AI), including machine learning algorithms, predictive analytics, and real-time data processing, enables dynamic monitoring, adaptive control, and performance optimization of TES units. The synergistic deployment of sensor networks, Internet of Things (IoT) architectures, and digital twin platforms ensures seamless data acquisition and system modeling, facilitating informed decision-making and autonomous management. This chapter underscores the critical importance of embedding social pedagogy and ethical considerations into the development and deployment of smart TES systems. By doing so, it addresses the need for public engagement, regulatory coherence, and equitable access in the context of advanced energy technologies. Future trajectories discussed include the development of multifunctional and stimuli-responsive NePCMs, AI-powered thermal self-healing mechanisms, and scalable deployment strategies within smart cities and decentralized energy grids. The proposed interdisciplinary framework bridges the gap between material innovation, intelligent systems engineering, and human-centric policy design—laying the foundation for the next generation of sustainable energy infrastructure.</jats:p>

, Dr. Rico Fernandez

International Journal of Research in Engineering • 0

<jats:p>This article reviews the recent advancements in solar thermal cooling technologies, highlighting the significance of renewable energy for cooling applications, especially in regions with high cooling demand and abundant sunlight. Solar thermal cooling utilizes the heat from the sun to drive cooling processes, and this review explores the primary methods, including absorption chillers, adsorption chillers, and solar-assisted vapor compression systems. We also discuss the latest innovations, challenges, and the future outlook of solar thermal cooling in commercial and residential applications. The study further emphasizes the environmental and economic benefits of these technologies, particularly in reducing carbon footprints and operational costs.</jats:p>

Rajkumar Malviya, Veeresh Vishwakarma, Prashant V. Baredar et al.

Solar Thermal Systems: Thermal Analysis and its Application • 2022

<jats:p>With the rising population and continuous depletion of our natural resources, it has become very tough for everyone to meet their basic needs of food and water. Also, at the rate with which the water-stressed area continues to rise, we soon will be facing a huge water crisis. This chapter specifically talks about India and its potential to make a switch from conventional methods of water usage and switch to a renewable energy-based water desalination unit. This chapter presents an elaborate analysis of the Indian peninsular region and talks about the major cities’ comparative performance in the basic design of the solar humidificationdehumidification desalination unit. It can be concluded that the southern-most area has a very large potential for setting up an economically feasible desalination unit. Various parameters are discussed, like humidity ratio, outgoing airstream temperature, and mass rate of evaporated water. As Chennai has the best performance for the particular unit for most of the year, with productivity reaching 44 kg/day, the least favorable site seems to be Puri in Odisha, where productivity remains less and constant at a maximum of 34 kg/day during summers.</jats:p>

A.K. Dhamneya, M.K. Gaur, Vikas Kumar Thakur et al.

Solar Thermal Systems: Thermal Analysis and its Application • 2022

<jats:p>The consumption of conventional energy has increased exponentially due to the ever-increasing population of the world. Studies revealed that cooking activities contribute majorly to the overall energy consumption throughout the globe, further accounting for an increasing global warming potential. Being an enormous, virtually unlimited, and expandable source, solar energy turns out to be a favorable solution to the situation. Solar energy's widespread availability and processing technologies make the thermal energy conversion process easily accessible. Hence, solar energy has emerged as a ‘natural solution’ to the energy crisis and the adverse environmental impact, such as the greenhouse effect. This chapter outlines the various solar cooker fundamentals and development in different types of solar cookers, namely box type, panel, funnel type, parabolic type, and indirect type, along with the application of different solar cookers.</jats:p>

Rishika Shah, R.K. Pandit, M.K. Gaur

Solar Thermal Systems: Thermal Analysis and its Application • 2022

<jats:p>Many harmful effects on the environment can be observed over the past decades due to the extensive usage of non-renewable energy. Most discussed and harmful are the ever-changing global climate change scenarios and their aftermath. As a point of fact, a major part of the world’s energy consumption is dependent on non-renewable energy sources, such as petroleum, oil, coal, and gas. Unquestionably, these fossil fuels contribute a great deal to greenhouse gas emissions, carbon dioxide, methane, etc., which further leads to global health issues, global warming, and climate change. With the emergence of sustainable development as a holistic concept since the late 1980s, the issue of global warming has been given prominent attention. It is evident that failure to curb global warming has led to slower progress in achieving sustainable development. About 30% of energy demand is from the built environment sector, which is also responsible for contributing 28% of carbon emissions and continues to add an estimated 1% every year, according to reports by UN Environment [1]. Therefore, the fossil fuel-based energy systems are antagonistic with the goals of sustainable development agendas. Hence, using renewable sources in harnessing clean energy for the built environment has not remained a choice but a fundamental need. Solar energy is one of the cleanest renewable energy sources that provide solutions to climate change and global warming. Often termed as the alternative energy source against oil and coal-based energy sources, solar energy has the potential for abundant availability and is an economical way with a lower ecological and environmental footprint, leading to a better quality of life. Thus, there is a massive amount of global interest in harnessing solar energy for its application and development in building systems.</jats:p>

Desh Bandhu Singh, G.N. Tiwari

Solar Thermal Systems: Thermal Analysis and its Application • 2022

<jats:p>The design, analysis and modeling of solar energy-based water purifiers, commonly known as a solar still, which is based on the greenhouse effect, is the requirement of time as there is a scarcity of freshwater throughout the globe. The technology of purifying dirty water using solar energy is a promising solution for simplifying contemporary water scarcity as this technology does not create any bad effect on the surroundings, unlike conventional water purification technology, which creates a lot of polluting elements and ultimately has become problematic for the environment. Most solar energy-based water purifiers are self-sustainable, and they can be installed in remote locations where sunlight and source of impure water are available in abundance. This solar energy-based technology of water purification should perform better in hilly locations as the intensity of light is higher than the intensity of light in fields. The current chapter deals with the thermal modeling of different types of passive and active solar stills, including solar stills loaded with water-based nanofluids, followed by their energy and exergy analyses.</jats:p>

Zülâl Muganlı, Ismail Butun, Ghazaleh Gharib et al.

Energy Advances • 2024

New-generation sustainable energy systems serve as major tools to mitigate the greenhouse gas emissions and effects of climate change. Biophotovoltaics (BPVs) presents an eco-friendly approach by employing solar energy to...

Farshid Salimijazi, Jaehwan Kim, Alexa M. Schmitz et al.

• 2020

Electromicrobial production technologies (EMP) aim to combine renewable electricity and microbial metabolism. We have constructed molecular to reactor scale models of EMP systems using H2-oxidation and extracellular electron transfer (EET). We predict the electrical-to-biofuel conversion efficiency could rise to ≥ 52% with in vivo CO2-fixation. H2 and EET-mediated EMP both need reactors with high surface areas. H2-diffusion at ambient pressure requires areas 20 to 2,000 times that of the solar photovoltaic (PV) supplying the system. Agitation can reduce this to less than the PV area, and the power needed becomes negligible when storing ≥ 1.1 megawatts. EET-mediated systems can be built that are ≤ 10 times the PV area and have minimal resistive energy losses if a conductive extracellular matrix (ECM) with a resistivity and height seen in natural conductive biofilms is used. The system area can be reduced to less than the PV area if the ECM conductivity and height are increased to those of conductive artificial polymers. Schemes that use electrochemical CO2-fixation could achieve electrical-to-fuel efficiencies of almost 50% with no complications of O2-sensitivity.

A. Yadav, R. Nair

2021 International Conference on Computational Intelligence and Knowledge Economy (ICCIKE) • 2021

Renewable energy sources and technological advancements are playing a significant role in the current scenario. Biophotovoltaics depicts a relatively novel output in the field of research using the microbial system. The process of harvesting light energy and converting them to electrical energy by photosynthetic organisms is the basic mechanism of this technology. The crucial role is the extraction of electrons from the photosynthetic microbe followed by transfer to the anode. In this review, we are summarizing the significant properties of the biological photovoltaic system and the role of cyanobacteria as a key microbial model for the energy system. The types of BPV along with its light-harvesting sources and electron transfer mechanisms are extensively discussed. The variant species of cyanobacteria have been analyzed with different conditions of the anode, power system, and their consecutive efficiencies. The role of the redox mediator in enhancing the output by creating the redox homeostasis in autotrophs is another critical part of our study.

Abdul Waris, F. Ghaith

ASME 2022 Power Conference • 2022

Many countries around the world depend primarily on seawater desalination process which is an energy-intensive process and incorporates high electricity consumption. In United Arab Emirates (UAE), desalinated seawater accounts for almost 89.9% of the country’s water needs. The average residential water consumption is 550 liters per capita per day which is almost 82% higher than the world average. This paper aims to design a greywater treatment plant which is fully powered by solar photovoltaic (PV) panels. The proposed water treatment plant consists of a three-step filtration process to treat greywater. Initially, the collected greywater from households is pumped to a multimedia filter to reduce the level of turbidity followed by pumping the water at high pressure through Reverse Osmosis unit and finally passing the water in the chlorination chamber to remove odor and prevent microbial growth. The proposed system was implemented to the case study of a villa community located in Dubai which comprises 38 villas and accommodates a total of about 152 residents. The proposed water treatment plant has a capacity of producing about 83 m3 of clean water per day at a high recovery rate of 67%. The solar system proved to be efficient by providing energy of 57397 kWh which was enough to power entirely the greywater treatment plant. Cost analysis was carried out to assess the economic feasibility of the proposed plant. The system resulted in a tangible reduction in carbon dioxide emissions of 204 ton/year.

Raymond Daniel Rodriguez Martinez

Clean Energy • 2024

Developing a sustainable energy model is imperative considering the current trend towards decarbonizing sectors worldwide. For this purpose, Venezuela was used as a reference to propose an energy model focused on taking advantage of plant photosynthesis through microbial–vegetable fuel cells together with an agro-photovoltaic system to enhance energy and agricultural production. Energy production from the cells was estimated using an average power density of 264 mW/m2 over 4% of the areas destined for crops in the entire Venezuelan region, obtaining an annual production of 19.889 GWh/year. In contrast, the energy production of the agro-photovoltaic system was modelled using PVsyst software on 50% of the area used for the cells distributed throughout the states of Anzoátegui, Guárico, Monagas and Portuguesa according to their meteorological conditions, solar irradiation and agricultural activity, resulting in 3 703 417 GWh/year. The resulting whole system proved to be able to cover >10 times the installed electricity generation capacity at a national level and, together with the tremendous scalability of the microbial fuel cells, it shows that Venezuela has a high potential for the production and distribution of clean energy.

Yonas Lamore, A. Beyene, Samuel Fekadu et al.

Applied Water Science • 2018

Unaffordable construction cost of conventional water treatment plant and distribution system in most developing countries makes difficult to provide safe and adequate water for all households, especially for the rural setup. Water treatment at the source can be the best alternative. Solar disinfection is one alternative among point of use treatments. In this study, aqua lens, photovoltaic box and glass bottle were used subsequent to plant coagulants to evaluate microbial reduction potentials. Laboratory- and field-based experiments were conducted from May to August 2016. The Escherichia coli, total coliforms and heterotrophic plate counts were used as indicator organisms. The result indicated that aqua lens (AL), photovoltaic box (PV) and glass bottle (GB) have high inactivation rate subsequently almost for all indicator organisms in short solar exposure time. Total coliforms were inactivated in AL (SD = 15.8 °C, R2 = 0.92) followed by PV inactivation temperature association (SD = 11.6 C, R2 = 0.90), and the GB concentrator was inactivated (SD = 10.9 °C, R2 = 0.70) at turbidity level of 3.41 NTU. As the study indicated, aqua lens coupled with Moringa oleifera coagulant can be an effective with minimum cost for household water treatment system. The study also concludes heterotrophic bacteria were more resistant than other types of bacteria in SODIS with similar exposure time.

N. Pichel, M. Vivar, M. Fuentes

2018 IEEE 7th World Conference on Photovoltaic Energy Conversion (WCPEC) (A Joint Conference of 45th IEEE PVSC, 28th PVSEC &amp; 34th EU PVSEC) • 2018

A hybrid solar water disinfection and energy generation system was subjected to a microbial kinetic study to apply system optimizations. E. coli response and photovoltaic performance was studied using natural water sources and natural sunlight. Results showed that under strong climatic conditions the time required for the solar disinfection could be reduced by half, increasing the quantity of treated water and improving the SOLWAT energy output due to the cooling effect of the water being purified on the top of the PV module. The module could even be benefited from lower temperatures when using reduced treatments times.

Viviane Faria Morais Jotta, G. García, P. Fonseca et al.

Journal of Applied Microbiology • 2024

AIMS Biofilms are complex microbial cell aggregates that attach to different surfaces in nature, industrial environments, or hospital settings. In photovoltaic panels (PVs), biofilms are related to significant energy conversion losses. In this study, our aim was to characterize the communities of microorganisms and the genes involved in biofilm formation. METHODS AND RESULTS In this study, biofilm samples collected from a PV system installed in southeastern Brazil were analyzed through shotgun metagenomics, and the microbial communities and genes involved in biofilm formation were investigated. A total of 2 030 different genera were identified in the samples, many of which were classified as extremophiles or producers of exopolysaccharides. Bacteria prevailed in the samples (89%), mainly the genera Mucilaginibacter, Microbacterium, Pedobacter, Massilia, and Hymenobacter. The functional annotation revealed more than 12 000 genes related to biofilm formation and stress response. Genes involved in the iron transport and synthesis of c-di-GMP and c-AMP second messengers were abundant in the samples. The pathways related to these components play a crucial role in biofilm formation and could be promising targets for preventing biofilm formation in the PV. In addition, Raman spectroscopy analysis indicated the presence of hematite, goethite, and ferrite, consistent with the mineralogical composition of the regional soil and metal-resistant bacteria. CONCLUSIONS Taken together, our findings reveal that PV biofilms are a promising source of microorganisms of industrial interest and genes of central importance in regulating biofilm formation and persistence.

H. Dvořáčková, Jan Dvořáček, V. Vlček

Cogent Food &amp; Agriculture • 2024

Abstract New photovoltaic panels are installed on agricultural land every day and yet their effect on the quality of the soil has not yet been fully verified. Unfortunately, there are not many scientific works that focus on the effect of photovoltaic panels on real soil in real conditions. The presented work intended to establish the basic principles through which the placement of photovoltaic panels changes the quality of the surrounding soil. Since the soil is a very complex system, six basic soil properties were worked on, which were labeled as soil ‘master properties’ in the work by Kuzyakov and Zamanian. It was found that the photovol power plants can have a positive effect on the soil under certain conditions. According to our conclusions, it can be assumed that the placement of PV panels will have a positive effect on a number of soil properties, we can mainly expect an increase in the stability of soil aggregates, an increase in the content of organic matter and an increased development of the microbial community. Graphical Abstract

J. A. Siggers, Matt Sturchio, Lillian Gordon et al.

Global Change Biology • 2025

ABSTRACT The rapid expansion of photovoltaic (PV) energy production has generated concern over its potential ecosystem impacts. PV arrays induce unique microenvironmental conditions by altering resource availability and substantially impacting aboveground processes. However, the belowground consequences of PV development are understudied, limiting our understanding of overall ecosystem impacts. Here, we paired soil physiochemical, molecular, and functional analyses with aboveground measures to assess plant–soil–microbial responses to distinct microsites beneath a single‐axis tracking PV system in a semi‐arid C3 grassland. We hypothesized that each PV microsite would harbor a unique suite of soil physiochemical properties and microbiomes. We found only subtle differences in soil organic matter and pH, corresponding with aboveground productivity patterns, but other physiochemical properties remained unchanged. However, soil microbial community structure and function differed markedly across PV microsites and from a reference grassland plot. Within the array, microbial decomposition rates were highest where plant productivity and organic matter were greatest, but surprisingly lowest where soil moisture remained elevated throughout the growing season. Overall, these findings suggest that PV arrays create disparate patterns of soil microbial community structure and function, which may feedback to influence overall ecosystem functionality. Coarse measures of soil physiochemical properties, such as total carbon, may overlook key impacts of PV development.

Abderrahmen Ben Chaabene, Khira Ouelhazi

Solar Radiation - Measurement, Modeling and Forecasting Techniques for Photovoltaic Solar Energy Applications • 0

<jats:p>The major problem of the industrial sectors is to efficiently supply their energy requirement. Renewable energy sources, in particular solar energy, are intermittently accessible widely around the world. Photovoltaics (PV) technology converts sunlight to electricity. In this work, we present a contribution dealing with a new mathematic development of tracking control technique based on Variable Structure Model Reference Adaptive Following (VSMRAF) control applied to systems coupled with solar sources. This control technique requires the system to follow a reference model (the solar radiation model) by adjusting its dynamic and ensuring the minimal value of error between the plant dynamics and that of the reference solar radiation model. This chapter provides a new theoretical analysis validated by simulation and experimental results to assure optimum operating conditions for solar photovoltaic systems.</jats:p>

Madhumita Das, Ratan Mandal

Nanomaterials and Energy • 2023

<jats:p> India is a tropical country that gets a significant amount of solar irradiation that is suitable for photovoltaic (PV) applications. The country is also endowed with wind energy in its large coastal areas. India is an agro-economic country that has a growing need for irrigation. Utilization of hybrid renewable energy for the agricultural needs of the country would be a step toward a sustainable future. For the environmental conditions of Haldia, India, a stand-alone PV–wind–lead-acid battery hybrid renewable energy system (HRES) was developed to cater to the needs of agricultural activities. An investigation was conducted on the impact of PV penetration on the system wind energy capacity, battery capacity, capacity shortage, net present cost, cost of energy (COE), PV and wind energy percentage and surplus energy produced. The optimization was based on the assumption that the HRES had no unmet load and the lowest COE. This research provided a range of wind energy capacities for the location with no unmet loads. The research discovered the ideal HRES of the site with a COE of US$0.312/kWh. This study may help farmers by boosting their reliance on power from renewable energy sources and decreasing their dependency on grid power for agricultural activities. </jats:p>

Anbarasi MP, Kanthalakshmi S

• 0

<jats:title>Abstract</jats:title> <jats:p>A control strategy for power maximization which is an important mechanism to extract maximum power under changing environmental conditions using Adaptive Particle Swarm Optimization (APSO) is proposed in this paper. An Adaptive Inertia Weighting Factor (AIWF) is utilised in the velocity update equation of traditional PSO for the improvement in speed of convergence and precision in tracking Maximum Power Point (MPP) in standalone Photovoltaic system. Adaptation of weights based on the success rate of particles towards maximum power extraction is the most promising feature of AIWF. The inertia weight is kept constant in traditional PSO for the complete duration of optimization process. The MPPT in PV system poses a dynamic optimization problem and the proposed APSO approach paves way not only to track MPP under uniform irradiation conditions, but also to track MPP under non uniform irradiation conditions. Simulations are done in MATLAB/Simulink environment to verify the effectiveness of proposed technique in comparison with the existing PSO technique. With change in irradiation and temperature, the APSO technique is found to provide better results in terms of tracking speed and efficiency. Hardware utilizing dSPACE DS1104 controller board is developed in the laboratory to verify the effectiveness of APSO method in real time.</jats:p>

Jawad Sarwar, Arshmah Hasnain, Ahmed Abbas et al.

Thermal Science • 2021

<jats:p>In this work, a novel design of a concentrated photovoltaic system with thermal management using phase change material is analyzed. The novelty lies in utilizing two mono-facial photovoltaic cells, installing one on upper side of the receiver to receive non-concentrated sunlight and installing another photovoltaic cell on bottom side to receive concentrated sunlight. An RT47 (melting range of 41-48?) phase change material enclosed in an aluminum containment regulates the temperature of the system. Parabolic trough concentrator is used to focus sunlight on the bottom photovoltaic cell with a concentration ratio of 25. A finite volume based coupled thermal, electrical and optical model is developed and the system is analyzed for environmental conditions of Doha, Qatar. Temperature regulation and electrical power output of upper photovoltaic cell and bottom concentrated photovoltaic cell of proposed design are compared to a conventional flat plate system. Analysis is made for one day of each month of a year. It is found that the proposed design maintains the temperature below 85? for all months of a year. The performance of the proposed system is comparable to the conventional flat plate system and excels it with power production in the range of ?4.7% and +21.7%.</jats:p>

Fatima Haidar, Imen Mrad, Quang Truc Dam

Engineering Perspective • 0

<jats:p>In this research, the integration of an alkaline electrolyzer system with a photovoltaic (PV) array is explored to facilitate the green production of hydrogen. By directly coupling these two technologies, solar energy is harnessed to drive the electrolysis process, consequently generating hydrogen as a sustainable energy carrier. To enable accurate simulation and analysis of the integrated system, a novel methodology is introduced for identifying and quantifying the various parameters crucial for understanding the electrical behavior of the alkaline electrolyzer system. Through this method, the interplay between the PV array's output and the electrolyzer's operation can be comprehensively captured, allowing for precise modeling of the overall system dynamics. Moreover, mathematical equations are established to provide insights into the anticipated quantities of hydrogen generated by the electrolyzer system under different operating conditions. These equations serve as predictive tools, offering valuable insights into the system's performance and efficiency, essential for optimizing its design and operation. The proposed methodology and equations are implemented and validated using the MATLAB/Simulink environment, a powerful tool for simulating complex systems. By leveraging this platform, the integrated PV-electrolyzer system can be simulated with high fidelity, capturing its dynamic behavior and performance characteristics under varying scenarios. The promotion of renewable energy-based solutions for sustainable hydrogen production is aimed to be facilitated by this research, thereby contributing to the transition towards a greener and more resilient energy future.</jats:p>

Lilik J Awalin, Syahirah Abd Halim, Syahiman et al.

Wind Engineering • 2022

<jats:p> This paper presents the performance investigation of voltage and current for dynamic model of the wind turbine. In this study, the various numbers of wind turbine speed are applied in the simulation. This treatment is intended to see how much influence the turbine speed has on the voltage and current output. IEEE 14 bus system is integrated to the wind turbine in order to observe the impact of on-grid connection to the voltage and current performance. How to model wind turbine in PSCAD simulation software also discussed in this paper. The detail of supporting components in designing a wind turbine system and their functions are also explained. Several values of turbine speed are also considered in this paper as a study material in seeing the performance of wind turbines. The relationship between wind speed and pitch angle will also be discussed to ensure that the wind turbine is not damaged. In order to prove the accuracy of the simulation model, the obtained measurement generation of active power from the wind turbine is matched with the manual calculation. Based on the various wind speed values that have been tested, this can be the basis for the application of wind turbine (renewable energy) design development for further research. </jats:p>

Mitch Clement, Timothy Magee, Edith Zagona

Wind Engineering • 2014

<jats:p> Hydropower is considered a good resource to provide the needed flexibility to balance wind variability, but its flexibility is limited by non-power constraints associated with environmental and water management objectives not fully accounted for in previous wind integration studies. We present a method for a more realistic evaluation of integrated hydropower and wind using the RiverWare river system and hydropower modeling tool. The model provides a representation of physical and economic characteristics of the hydro system with the limitations from realistic non-power constraints. A test case is analyzed for a range of hydrologic conditions, levels of policy constraints and wind penetrations from 0 to 40 percent. Results show that at low penetrations wind adds economic value but has diminishing value as installed capacity increases, primarily due to increased reserve requirements. Increased wind generation increases policy constraint violations. Non-power constraints can significantly limit the total economic value of the integrated system. </jats:p>

Ramesh Kumar Behara, Kavita Behara

Wind Turbines - Advances and Challenges in Design, Manufacture and Operation • 0

<jats:p>Recently, scientists and academics are discovering progressive improvements in the arena of wind power technology economically and reliably, allowing them to produce electricity focusing on renewable energy resources. Wind turbines (WT) using the Doubly Fed Induction Generators (DFIGs) have attracted particular attention because of their advantages such as variable speed constant frequency (VSCF) operation, independent control capabilities for maximum power point tracking (MPPT), active and reactive power controls, and voltage control strategy at the point of common coupling (PCC). When such resources have to be integrated into the existing power system, the operation becomes more challenging, particularly in terms of stability, security, and reliability. A DFIG system with its control strategies is simulated on MATLAB software. This entails the rapid control prototype testing of grid-connected, variable speed DFIG wind turbines to investigate the WT’s steady-state and dynamic behavior under normal and disturbed wind conditions. To augment the transient stability of DFIG, the simulation results for the active and reactive power of conventional controllers are compared with the adaptive tracking, self-tuned feed-forward PI controller model for optimum performance. Conclusive outcomes manifest the superior robustness of the feed-forward PI controller in terms of rising time, settling time, and overshoot value.</jats:p>

Murat LÜY, Nuri Alper METİN

International Scientific and Vocational Studies Journal • 0

<jats:p xml:lang="tr">Due to the increase in electricity consumption in the world, the tendency to increase resource diversity in the electricity generation section has increased. With the decrease in the reserves of petroleum and derivative products used in traditional energy production systems, energy production has turned to renewable energy sources. Examples of renewable energy sources are the sun, wind turbines, and fuel cells. In order to provide sustainable energy production in wind turbines, the blades and body must be protected. In this study, the blade pitch angle control of the wind turbine is realized with the PID controller and the wind turbine is protected from high speeds. The coefficient control of the PID controller is determined by the PSO (Particle Swarm Optimization) and Ziegler Nichols method. Simulation was carried out in MATLAB/Simulink environment. It has been observed that the PID coefficient parameters optimized with PSO in the pitch angle control process reach the reference power value in a shorter time compared to the PID parameter values calculated with Ziegler Nichols. In addition, it was observed that the oscillation value was less at the reference power reached and the pitch angle increased.</jats:p>

Sebastian Hippel, Clemens Jauch

Wind Energy • 2019

<jats:title>Abstract</jats:title><jats:p>In this paper, the impact on the mechanical loads of a wind turbine due to a previously proposed hydraulic‐pneumatic flywheel system is analysed. Load simulations are performed for the National Renewable Energy Laboratory (NREL) 5‐MW wind turbine using fatigue, aerodynamics, structures, and turbulence (FAST). It is discussed why FAST is applied although it cannot simulate variable rotor inertia. Several flywheel configurations, which increase the rotor inertia of the 5‐MW wind turbine by 15%, are implemented in the 61.5‐m rotor blade. Load simulations are performed twice for each configuration: Firstly, the flywheel system is discharged, and secondly, the flywheel is charged. The change in ultimate and fatigue loads on the tower, the low speed shaft, and the rotor blades is juxtaposed for all flywheel configurations. As the blades are mainly affected by the flywheel system, the increase in ultimate and fatigue loads of the blade is evaluated. Simulation results show that the initial design of the flywheel system causes the lowest impact on the mechanical loads of the rotor blades although this configuration is the heaviest.</jats:p>

Gaurav Gadhiya, Uravshi Patel, Pushpendra Singh Chauhan

Annals of Arid Zone • 0

<jats:p>The constant rise in fuel prices and the impact of emissions from fuel into the atmosphere made has it necessary to look at solar energy as a source of power. The fossil fuel-powered lawn mowers have a tendency to freeze and not operate in the chilly and harsh atmosphere besides causing air pollution and noise pollution. The objective of this research was to design and develop a lawn cutting machine powered by solar energy and is user-and environmentally friendly, less noisy and lighter in weight. The designed lawn mower comprises one brushless direct current (BLDC) motor, solar panel, battery and charge controller. The solar lawn mower has an efficiency of 81.33%. The developed model can used in playgrounds, lawns, and golf courses to achieve environmental sustainability goals, save energy, minimise noise pollution.</jats:p>

Masaya Matsuki, Shusaku Hirakawa

Water Science &amp; Technology • 2023

<jats:title>Abstract</jats:title> <jats:p/> <jats:p>Sediment microbial fuel cells (SMFCs) represent a burgeoning technology that allows the remediation of sediments, such as nutrient suppression, while concurrently generating electricity. However, there is a limitation in that the nutrient suppression effect is restricted to a narrow range near the electrode. To address this issue, we developed an SMFC-aeration system, which intermittently aerates the overlying water with the power of SMFCs, thereby enhancing the nutrient suppression effect of SMFCs. The SMFC-aeration system achieved stable charge/discharge cycles through a capacitor-based circuit and aerated the overlying water. The dissolved NH4+ and NO2- concentrations in the overlying water decreased. Suppression in the dissolved NH4+ concentration near the anodes was also noticed compared to a consortium that employed only SMFCs. These findings were brought about by the synergistic effect of the SMFC-aeration system, which enabled the remediation of sediments and overlying water. To our knowledge, this is the first report on the intermittent operation of pumps by SMFCs, the increase of DO, and nutrient suppression. The SMFC-aeration system holds great potential as an environmental remediation method in closed-water areas in the future.</jats:p>

Ch Venkateswara Rao, Somarouthu V G V A Prasad

Solar Thermal Technologies and Nano-Enhanced Phase Change Materials for High-Efficiency Electric and Solar Mobility • 2025

<jats:p>The integration of solar-powered hydrogen fuel cells with advanced phase change materials (PCMs) represents a promising frontier in the pursuit of sustainable transportation solutions. This chapter explores the critical intersection of renewable energy conversion, efficient hydrogen storage, and intelligent system management to address key challenges in clean mobility. Emphasis is placed on the role of PCMs in enhancing thermal regulation and safety during hydrogen storage, while algorithmic intelligence—including machine learning and real-time monitoring—enables optimized hydrogen production and system reliability. By the chapter underscores the significance of social pedagogy frameworks to foster public awareness, trust, and participatory engagement essential for widespread adoption. By bridging cutting-edge technological advancements with data-driven decision-making and inclusive social strategies, this work presents a comprehensive roadmap for accelerating the transition to low-carbon transport infrastructures. The insights offered aim to guide future research, policy development, and industrial applications, ensuring that hydrogen technologies fulfill their potential as scalable, safe, and socially accepted solutions within the global energy landscape.</jats:p>

Elyor Shukurov, Taiwo Bamgboye, Matin Rafipour Langeroudi

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<jats:p>Water-Energy-Food Challenges in Central Asia: A Comparative Study of Solar and Fossil Fuel-Powered Irrigation Systems Doctoral researcher Matin Rafipour Langeroudi, Doctoral researcher Taiwo Bamgboye University of OuluWater-related challenges in transboundary river basins are exacerbated by climate change, historical basin developments, and competing national interests. In Central Asia, the Amu Darya River, essential for agriculture in downstream countries like Uzbekistan, faces significant threats from upstream infrastructure projects such as the Rogun Dam in Tajikistan and the Qosh Tepa Canal in Afghanistan. These projects are expected to reduce downstream water flow by up to 30% and 15%, respectively, significantly impacting irrigation systems, increasing energy demands for pumping, and straining agricultural productivity and socio-economic stability. The aim of this research addresses the impacts of upstream developments on water availability and explores adaptive strategies for irrigation sustainability. A comparative analysis of solar-powered and fossil fuel-powered irrigation systems will be conducted to assess their efficiency, environmental impact, and economic feasibility. Environmental assessments will estimate greenhouse gas emissions, and cost-benefit analyses will evaluate energy efficiency and long-term viability. Key metrics, including energy consumption, water output, and operational costs, will be analyzed to identify trade-offs and propose sustainable solutions. The study’s findings aim to mitigate the impacts of reduced water availability by promoting renewable energy integration and adaptive irrigation practices. By addressing these challenges within the Water-Energy-Food (WEF) nexus, this research offers critical insights to guide policymakers and stakeholders in developing sustainable water resource management strategies, transitioning to cleaner energy systems, and enhancing agricultural resilience under the dual pressures of upstream developments and climate change. Keywords: Amu Darya Basin, Upstream infrastructure projects, Water resource management, Irrigation systems, Agricultural productivity, Solar energy in agriculture, Fossil fuel-based pumping system, Transboundary water challenges, Rogun Dam impact, Qosh-Tepa canal, Water-Energy-Food nexus, Renewable energy solutions.</jats:p>

Yelizaveta Rassadkina, Spencer Roth, Tamar Barkay

Aresty Rutgers Undergraduate Research Journal • 0

<jats:p>Yellowstone National Park is home to many different hot springs, lakes, geysers, pools, and basins that range in pH, chemical composition, and temperature. These different environmental variations provide a broad range of conditions that select and grow diverse communities of microorganisms. In this study, we collected samples from geochemically diverse lakes and springs to characterize the microbial communities present through 16S rRNA metagenomic analysis. This information was then used to observe how various microorganisms survive in high mercury environments. The results show the presence of microorganisms that have been studied in previous literature. The results also depict gradients of microorganisms including thermophilic bacteria and archaea that exist in these extreme environments. In addition, beta diversity analyses of the sequence data showed site clustering based primarily on temperature instead of pH or sample site, suggesting that while pH, temperature, and sample site were all shown to be significant, temperature is the strongest factor driving microorganism community development. While it is important to characterize the microorganism community present, it is also important to understand how this community functions as a result of its selection. Along with looking at community composition, genomic material was tested to see if it contained mercury methylating (hgcA) or mercury reducing (merA) genes. Out of 22 samples, three of them were observed to have merA genes, while no samples had hgcA genes. These results indicate that microorganisms in Mustard and Nymph Springs may use mercury reduction. Understanding how microorganisms survive in environments with high concentrations of toxic pollutants is crucial because it can be used as a model to better understand mechanisms of resistance and the biogeochemical cycle, as well as for bioremediation and other solutions to anthropogenic problems. </jats:p>

Yusei Masaki, Shin Ichi Hirano, Naoko Okibe

Advanced Materials Research • 0

<jats:p>Blood Pond Hell (Chinoike Jigoku) is located in the hot spring town of Beppu, in Kyushu Island of Japan, and features a unique hot, acidic, red-coloured pond. This study aimed to investigate the microbial diversity in this unique extreme environment and eventually to isolate useful acidophilic microbes. The initial PCR (using bacteria-or archaea-specific primers) on environmental samples detected the presence of bacteria, but not archaea. The following random sequencing analysis confirmed the presence of a large bacterial diversity at the site (123 clones comprising 18 bacterial and 1 archaeal genera), including those closely related to known autotrophic and heterotrophic acidophiles (<jats:italic>Acidithiobacillus</jats:italic>sp.,<jats:italic>Sulfobacillus</jats:italic>sp.,<jats:italic>Alicyclobacillus</jats:italic>sp.). Nonetheless, successive enrichment cultivation with Fe (III) under oxygen depletion lead to isolation of previously non-detected archaeal (<jats:italic>Sulfolobus</jats:italic>sp.) colonies on solid media. Two isolates showing Fe (III) reduction ability were named<jats:italic>Sulfolobus</jats:italic>sp. GA1 and GA2. The isolates were also found to reduce highly toxic Cr (VI) to less toxic/soluble Cr (III), demonstrating their potential utility in metal bioremediation.</jats:p>

Shekhar Nagar, Chandni Talwar, Mikael Motelica-Heino et al.

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<jats:title>Abstract</jats:title><jats:p><jats:fig id="ufig1" position="float" orientation="portrait" fig-type="figure"><jats:caption><jats:title>Graphical Abstract</jats:title></jats:caption><jats:graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="470874v1_ufig1" position="float" orientation="portrait" /></jats:fig></jats:p><jats:p>Sulfur Related Prokaryotes (SRP) residing in hot spring present good opportunity for exploring the limitless possibilities of integral ecosystem processes. Metagenomic analysis further expand the phylogenetic breadth of these extraordinary sulfur metabolizing microorganisms, as well a their complex metabolic networks and syntrophic interactions in environmental biosystems. Through this study, we explored and expanded the microbial genetic repertoire with focus on sulfur cycling genes through metagenomic analysis of sulfur (S) contaminated hot spring, located at the Northern Himalayas. The analysis revealed rich diversity of microbial consortia with established roles in S cycling such as<jats:italic>Pseudomonas</jats:italic>,<jats:italic>Thioalkalivibrio</jats:italic>,<jats:italic>Desulfovibrio</jats:italic>and<jats:italic>Desulfobulbaceae</jats:italic>(<jats:italic>Proteobacteria</jats:italic>). The major gene families inferred to be abundant across microbial mat, sediment and water were assigned to<jats:italic>Proteobacteria</jats:italic>as reflected from the RPKs (reads per kilobase) categorized into translation and ribosomal structure and biogenesis. Analysis of sequence similarity showed conserved pattern of both<jats:italic>dsrAB</jats:italic>genes (n=178) retrieved from all metagenomes while other sulfur disproportionation proteins were diverged due to different structural and chemical substrates. The diversity of sulfur oxidizing bacteria (SOB) and sulfate reducing bacteria (SRB) with conserved (r)<jats:italic>dsrAB</jats:italic>suggests for it to be an important adaptation for microbial fitness at this site. Here, we confirm that (i) SRBs belongs to<jats:italic>δ-Proteobacteria</jats:italic>occurring independent LGT of<jats:italic>dsr</jats:italic>genes to different and few novel lineages (ii) also, the oxidative and reductive<jats:italic>dsr</jats:italic>evolutionary time scale phylogeny, proved that the earliest (not first)<jats:italic>dsrAB</jats:italic>proteins belong to anaerobic<jats:italic>Thiobacillus</jats:italic>with other (<jats:italic>rdsr</jats:italic>) oxidizers. Further, the structural prediction of unassigned DsrAB proteins confirmed their relatedness with species of<jats:italic>Desulfovibrio</jats:italic>(TM score= 0.86; 0.98; 0.96) and<jats:italic>Archaeoglobus fulgidus</jats:italic>(TM score= 0.97; 0.98). We proposed that the genetic repertoire might provide the basis of studying time scale evolution and horizontal gene transfer of these genes in biogeochemical S cycling and the complementary genes could be implemented in biotechnology and bioremediation applications.</jats:p>

Peter F. Chuckran, Bruce Hungate, Egbert Schwartz et al.

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<jats:title>ABSTRACT</jats:title><jats:p>Free-living bacteria in nutrient limited environments often exhibit small genomes which curb the cost of reproduction – a phenomenon known as genomic streamlining. Streamlining has been associated with a suite of traits such as reduced GC content, fewer 16S rRNA copies, and a lower abundance of regulatory genes, such as sigma (σ) factors. Here, we analyzed these traits from 116 publicly available metagenomes derived from marine, soil, host associated, and thermophilic communities. In marine and thermophilic communities, genome size and GC content declined in parallel, but GC content was higher in thermophilic communities. In soils, the relationship between genome size and GC content was negative, suggesting a different selection pressure on genome size and GC content in soil bacteria. The abundance of σ-factors varied with average genome size, ecosystem type, and the specific functions regulated by the sigma factor. In marine environments, housekeeping and heat-shock σ-factor genes (<jats:italic>rpoD</jats:italic>and<jats:italic>rpoH</jats:italic>respectively) increased as genome size declined, and σ-factor responsible for flagella biosynthesis (<jats:italic>fliA</jats:italic>) decreased, suggesting a trade-off between nutrient conservation and chemotaxis. In soils, a high abundance of<jats:italic>fliA</jats:italic>and the stress response σ-factor gene (<jats:italic>rpoS</jats:italic>) was associated with smaller average genome size and often located in harsh and/or carbon-limited environments such as deserts or agricultural fields – suggesting an increased capacity for stress response and mobility in nutrient-poor soils. This work showcases how ecosystem-specific environmental constraints force trade-offs which are then embedded in the genomic features of bacteria in microbial communities, specifically genome size, GC content, and regulatory genes, and further highlights the importance of considering these features in microbial community analysis.</jats:p>

Zhenxin Zhou, Xiaohang Lu, Jianwen Yang et al.

Journal of Salt Lake Research • 2024

： The Qarhan Salt Lake sediments record the environmental evolution of the Qaidam Basin since the Late Pleistocene ， but sedimentary profiles since the Holocene are relatively scarce and chronological data are lacking. Two fine-clastic intercalations were found in each of the sedimentary sections of Beletan ， Beletan West and Dabuson sections of the Qarhan Salt Lake ， and corresponding photoluminescence samples were collected to study the age of sedimentation in the Qarhan Salt Lake during the Holocene. The results show that the two clastic layers in the Dabuson （ DBX ） section of Qarhan Salt Lake were formed at 6.2 ka （ 8.90 m ） and 2.8 ka （ 1.96 m ）， respectively ， while those in the Beletan section were formed at 2.9 ka （ 3.20 m ） and 0.9 ka （ 1.40 m ）， and those in the Beletan West section were formed at 2.4 ka （ 3.10 m ） and 0.7 ka （ 1.50 m ） .The Late Quaternary Salt Lake sediments are loose and soluble causing the samples to be complex in composition and origin ， resulting in the profile OSL data being much smaller than the 14 C and U-Th dating data （ 8 ～ 9 ka ） . The sedimentation rates （ from the bottom clastic layer to the surface layer ） calculated for the three profiles indicate that the sedimentation rate in the Dabuson section of the Qarhan Salt Lake is greater than that in the Beletan section ， while the sedimentation rate in the eastern part of Bele ‐ tan is higher than that in the western part. The sedimentation rates in the Qarhan Salt Lake and the Dongtai Genel Salt Lake are generally consistent.

Francesco Panico, Alessandro Minguzzi, Alberto Vertova et al.

• 0

<jats:p>More than a century has passed since the hypothesis was first proposed that primordial biological molecules could have formed from non-biological material with the input of some form of energy. Great efforts have been made to test possible energy sources in various environments and to determine whether the abiogenesis of biological molecules is possible. Among all the theories, the one involving hydrothermal vents has recently captured particular attention because it is based on the idea that the reduction of CO2 and the initiation of a proto-metabolism could have occurred by exploiting a life-like thermodynamic disequilibrium on mineral structure that shows structural and compositional similarities with some catalytic centre of enzimes.1&amp;#8211;3Hydrothermal Vent are geological formation generated from the upwelling of geothermal fluids into the ocean, there are two main types of HTV: black smokers (acidic ones) and white smokers (alkaline ones). In the Archean era Alkaline Hydrothermal Vent were generated by the reaction between alkaline (pH 10-11), warm and hydrogen rich fluids with the ocean rich in CO2 (acidic 10-11) and metal ions such as Fe, Ni, Zn, Co, Mn; here at the mixing point a mineral barrier precipitate, composed mainly of iron oxide and hydroxide, green rust and iron sulphide. Across this mineral membrane an electrochemical potential difference is generated, because of the disparity in pH and redox species between the inner and outer sides of the vent, this thermodynamic disequilibrium can be dissipated by coupling two opposite reactions: CO2 reduction and H2 oxidation, the two semireaction take place on the opposite sides of the same mineral structure but in two different environments: the first acidic, the second alkaline. 4Electrochemistry applied to the study of the behaviour of mineral materials from hydrothermal vents is a valuable tool because it allows for a precise investigation of the reactivity of material surfaces and correlates it with their electronic structure. 5A hydrothermal vent system can be modelled as a short-circuited fuel cell, with a continuous flow of reactants to the electrodes. These electrodes are made of the material that forms the barrier and are located in two different environments: the first electrode functions as a cathode for the reduction of CO2 in an acidic environment, while the second functions as an anode for the oxidation of hydrogen (or other molecules) in an alkaline environment. An electric current is recorded between the two short-circuited electrodes. This coupling of reactions can be represented in an Evans diagram, analogous to a corrosion process.Figure 1. Evans diagram in various conditionFigure 2. Short circuited fuel cell model of AHTVIn our laboratory, we developed a technique for synthesizing Mackinawite (FeSm) and Violarite (FeNi2S4). The samples have been characterized using spectroscopic, microscopic, and electrochemical methods. Using these materials, we have prepared electrodes for testing. A series of electrolysis experiments have demonstrated that these materials can electrochemically reduce CO2 at negative potentials as -1.2 V, producing formic acid, methanol, and carbon monoxide. The efficiency of this reaction decreases significantly when less extreme potentials are applied.&amp;#160;Figure 3. Production of formic acid and methanol during a potentiostatic electrolysis on Mackinawite or Violarite.The behaviour of the electrodes was studied by recording Tafel plots (log(I) vs E) and creating an Evans diagram. This diagram illustrates the operational conditions of pH, catalytic material, and reaction environment under which it is possible to couple the CO2 reduction and hydrogen oxidation reactions effectively. Subsequently, the short-circuited fuel cell was constructed, allowing for the measurement of the current flow (which is proportional to the reaction rate and indicates the cell's polarity) and the electric potential at which the coupled reactions occur.The results indicate that once the short-circuited fuel cell is assembled, in the absence of reactants and without a pH difference between the two compartments, no current is registered, suggesting that no reaction is occurring. However, upon introducing the CO2 and H2 reactants into their respective compartments, a pH gradient (6.5 vs 8.8) is established. Under these conditions, a reaction current is observed, with its direction indicating reduction at the pole containing CO2 and oxidation at the pole with H2. The potential at which this coupling occurs, on the synthesized metal sulphides materials, is -0.03 V vs SHE (@ pH 6.5), a value too positive to promote the CO2 reduction reaction. The limiting factor in this setup is the anodic reaction, so other conditions have been tested for improving the catalytic activity of the anode, changing electrolyte composition and pH, flux of reactant and even the composition of the electrode itself. For example, using platinum as the anode (a material known for its catalytic properties in reactions involving hydrogen), a coupling potential of -0.44 V is observed, a value within the range where the reduction reaction of CO2 at the cathode can occur.This approach to measurement and interpretation of Alkaline Hydrothermal Vent functioning represents, in our opinion, a groundbreaking development in the field of studies on this topic. The future challenge lies in identifying the optimal operational conditions that accurately simulate the real environment of an alkaline hydrothermal vent on the Archean ocean floor, capable of facilitating a spontaneous reduction reaction of CO2.References1.Russell, M. J. Green rust: The simple organizing &amp;#8216;seed&amp;#8217; of all life? Life vol. 8 Preprint at https://doi.org/10.3390/life8030035 (2018).2. Branscomb, E. &amp;amp; Russell, M. J. Frankenstein or a Submarine Alkaline Vent: Who is Responsible for Abiogenesis?: Part 2: As life is now, so it must have been in the beginning. BioEssays vol. 40 Preprint at https://doi.org/10.1002/bies.201700182 (2018).3. Russell, M. J., Nitschke, W. &amp;amp; Branscomb, E. The inevitable journey to being. Philosophical Transactions of the Royal Society B: Biological Sciences 368, (2013).4. Hudson, R. et al. CO2 reduction driven by a pH gradient. Proc Natl Acad Sci U S A 117, 22873&amp;#8211;22879 (2020).5. Nitschke, W. et al. Aqueous electrochemistry: The toolbox for life&amp;#8217;s emergence from redox disequilibria. Electrochemical Science Advances vol. 3 Preprint at https://doi.org/10.1002/elsa.202100192 (2023).&amp;#160;</jats:p>

Lindsey Smith, Heather Fullerton, Craig L. Moyer

PeerJ • 0

<jats:p>The microbiota of hydrothermal vents has been widely implicated in the dynamics of oceanic biogeochemical cycling. Lithotrophic organisms utilize reduced chemicals in the vent effluent for energy, which fuels carbon fixation, and their metabolic byproducts can then support higher trophic levels and high-biomass ecosystems. However, despite the important role these microorganisms play in our oceans, they are difficult to study. Most are resistant to culturing in a lab setting, so culture-independent methods are necessary to examine community composition. Targeted amplicon surveying has become the standard practice for assessing the structure and diversity of hydrothermal vent microbial communities. Here, the performance of primer pairs targeting the V3V4 and V4V5 variable regions of the SSU rRNA gene was assessed for use on environmental samples from microbial mats surrounding Kama‘ehuakanaloa Seamount, an iron-dominated hydrothermal vent system. Using the amplicon sequence variant (ASV) approach to taxonomic identification, the structure and diversity of microbial communities were elucidated, and both primer pairs generated robust data and comparable alpha diversity profiles. However, several distinct differences in community composition were identified between primer sets, including differential relative abundances of both bacterial and archaeal phyla. The primer choice was determined to be a significant driver of variation among the taxonomic profiles generated. Based on the higher quality of the raw sequences generated and on the breadth of abundant taxa found using the V4V5 primer set, it is determined as the most efficacious primer pair for whole-community surveys of microbial mats at Kama‘ehuakanaloa Seamount.</jats:p>