Lulu Fu, Yuting Wang, Jiaqiao Jiang et al.

ACS Applied Materials & Interfaces • 2021

Nanoconfinement ion transport, similar to that of biological ion channels, has attracted widespread research interest and offers prospects for broad applications in energy conversion and nanofluidic diodes. At present, various methods were adopted to improve the rectification performance of nanofluidic diodes including geometrical, chemical, and electrostatic asymmetries. However, contributions of the confinement effects within the channels were neglected, which can be a crucial factor for ion rectification behavior. In this research, we report an "ion pool"-structured nanofluidic diode to improve the confinement effect of the system, which was constructed based on an anodic aluminum oxide (AAO) nanoporous membrane sandwiched between zeolitic imidazolate framework 8 (ZIF-8) and tungsten oxide (WO3) thin membranes. A high rectification ratio of 192 is obtained through this nanofluidic system due to ions could be enriched or depleted sufficiently within the ion pool. Furthermore, this high-rectification-ratio ion pool-structured nanofluidic diode possessed pH-responsive and excellent ion selectivity. We developed it as a pH-responsive power gating for a salinity gradient harvesting device by controlling the surface charge density of the ion pool nanochannel narrow ends with different pH values, and hence, the ionic gate is switched between On and Off states, with a gating ratio of up to 27, which exhibited 8 times increase than ZIF-8-AAO and AAO-WO3 composite membranes. Significantly, the peculiar ion pool structure can generate high rectification ratios due to the confinement effect, which then achieves high gating ratios. Such ion pool-structured nanochannels created new avenues to design and optimize nanofluidic diodes and boosted their applications in energy conversion areas.

R. F. Morais, C. Morais, M. L. F. de et al.

African Journal of Biotechnology • 2018

In Brazil, elephant grass has been used for thermal energy production, due to the high productivity, energy efficiency, biological nitrogen fixation (BNF) and biomass quality for energy generation by direct burning. The use of biomass depends mainly on the energy balance and biomass characteristics for energy production. The aim of this study was to evaluate the biomass of dry matter yield, qualitative biomass variables and energy balance of two elephant grass genotypes. The experimental design was completely randomized blocks with two elephant grass cultivars (Gramafante and Roxo) and four replications per treatment. Five cultivation cycles were studied. Biomass yield and the contents of acid detergent fiber, lignin, cellulose, ash and calorific value were evaluated. The biomass yields of elephant grass cultivars varied between 12 and 24 Mg ha-1, where the lowest yields were presented by the cultivar Roxo, and the higher yields by Gramafante. The contents of fiber, lignin, cellulose and calorific value did not vary among the genotypes studied. An energy balance was calculated for the complete biomass production lifecycle of elephant grass and the overall energy output/input ratio was 15.1:1. The results show that the elephant grass has highly suitable materials for the production of energy by direct burning. Key words: Pennisetum purpureum, agroenergy, dry matter.

D. Ohayon, S. Inal

Advanced Materials • 2020

Conjugated polymers (CPs) possess a unique set of features setting them apart from other materials. These properties make them ideal when interfacing the biological world electronically. Their mixed electronic and ionic conductivity can be used to detect weak biological signals, deliver charged bioactive molecules, and mechanically or electrically stimulate tissues. CPs can be functionalized with various (bio)chemical moieties and blend with other functional materials, with the aim of modulating biological responses or endow specificity toward analytes of interest. They can absorb photons and generate electronic charges that are then used to stimulate cells or produce fuels. These polymers also have catalytic properties allowing them to harvest ambient energy and, along with their high capacitances, are promising materials for next‐generation power sources integrated with bioelectronic devices. In this perspective, an overview of the key properties of CPs and examination of operational mechanism of electronic devices that leverage these properties for specific applications in bioelectronics is provided. In addition to discussing the chemical structure–functionality relationships of CPs applied at the biological interface, the development of new chemistries and form factors that would bring forth next‐generation sensors, actuators, and their power sources, and, hence, advances in the field of organic bioelectronics is described.

Lu Xi-jia, P. Miles, F. Brock et al.

Abu Dhabi International Petroleum Exhibition & Conference • 2018

A significant portion of natural gas reserves around the world contain large quantities of sulfur species and carbon dioxide, which are often referred to as sour gas reservoirs. The IEA reports that more than 40% of the world's gas reserves are sour, with the number increasing to 60% for Middle Eastern gas reserves. Sulfur species, such as hydrogen sulfide (H2S), are highly corrosive when mixed with water and toxic to biological organisms. Compounds such as SO2 and SO3, which are derived from direct sour gas combustion, are also highly corrosive when mixed with water at the condensation temperature of sulfuric acid. Therefore, removal of H2S to trace levels from natural gas is typically considered as the first step of the utilization of sour gas for power generation. This paper presents a novel method which enables sour natural gas to be directly burned for power generation without pretreatment. Oxidized sulfur compounds are captured by limestone in the combustion process to eliminate downstream sulfur corrosion. The desulfurized flue gas then goes through a solids removal process before entering a gas turbine or a turbine expander for power generation. A steam cycle is used for waste heat recuperation from both the turbine exhaust stream and the solids stream to improve the cycle performance. Both air-combustion and oxy-combustion configurations were investigated and modeled using Aspen Plus. The design conditions of each cycle are within the operating envelope of commercially available equipment, including compressors, turbines and heat exchangers, enabling near-term deployment of the presented system. Aspen modeling results show the range of efficiency percentages for different cycles is from the low 40's to the low 50's on a Lower Heating Value (LHV) basis. Without pretreatment, the heating value of sulfur in the sour gas and the heat released from the limestone scrubbing process can be fully utilized for power generation, thus improving the cycle performance. Economic analyses estimate that the baseline air-combustion sour gas system with a conservative estimated Capex ($2142/kW) is 41% cheaper than NGCC in 2011, and is about 28% cheaper than advanced NGCC in 2022 on a simplified Levelized Cost of Electricity (LCOE) basis. The LCOE of the oxy-combustion sour gas system is estimated to be 53% lower than advanced NGCC in 2022 when the revenue from CO2 and Argon sales is taken into account. Therefore, the novel untreated sour gas combustion system presented in this paper enables the petroleum and power industries to use sour gas for power generation more efficiently and cost effectively, even with full carbon capture.

Vu Nguyen, Ren Zhu, Kory Jenkins et al.

Nature Communications • 2016

Peptides have attracted considerable attention due to their biocompatibility, functional molecular recognition and unique biological and electronic properties. The strong piezoelectricity in diphenylalanine peptide expands its technological potential as a smart material. However, its random and unswitchable polarization has been the roadblock to fulfilling its potential and hence the demonstration of a piezoelectric device remains lacking. Here we show the control of polarization with an electric field applied during the peptide self-assembly process. Uniform polarization is obtained in two opposite directions with an effective piezoelectric constant d33 reaching 17.9 pm V−1. We demonstrate the power generation with a peptide-based power generator that produces an open-circuit voltage of 1.4 V and a power density of 3.3 nW cm−2. Devices enabled by peptides with controlled piezoelectricity provide a renewable and biocompatible energy source for biomedical applications and open up a portal to the next generation of multi-functional electronics compatible with human tissue. Piezoelectricity in diphenylalanine peptide nanotubes (PNTs) suggests an avenue towards green piezoelectric devices. Here the authors show ‘smart’ PNTs whose polarization can be controlled with an electric field, and a resultant power generator which harvests biomechanical energy with high power density.

Xiao-di Huang, Jinhui Pang, Teng Zhou et al.

ACS Applied Polymer Materials • 2021

Ion conduction in nanoscale ion channels or ion pumps to produce electrical signals is the basis of many fundamental biological processes. Inspired by biological ion channels, artificial nanochanne...

Lulu Yang, Longfei Chang, Ying Hu et al.

Advanced Functional Materials • 2020

Mimicking the intelligence of biological organisms in artificial systems to design smart actuators that act autonomously in response to constant environmental stimuli is crucial to the construction of intelligent biomimetic robots and devices, but remains a great challenge. Here, a light‐driven autonomous carbon‐nanotube‐based bimorph actuator is developed through an elaborate structural design. This curled droplet‐shaped actuator can be simply driven by constant white light irradiation, self‐propelled by a light‐mechanical negative feedback loop created by light‐driven actuation, time delay in the photothermal response along the actuator, and good elasticity from the curled structure, performing a continuously self‐oscillating motion in a wavelike fashion, which mimics the human sit‐up motion. Moreover, this autonomous self‐oscillating motion can be further tuned by controlling the intensity and direction of the incident light. The autonomous actuator with continuous wavelike oscillating motion shows immense potential in light‐driven biomimetic soft robots and optical‐energy‐harvesting devices. Furthermore, a self‐locomotive artificial snake with phototaxis is constructed, which autonomously and continuously crawls toward the light source in a wave‐propagating manner under constant light irradiation. This snake can be placed on a substrate made of triboelectric materials to realize continuous electric output when exposed to constant light illumination.

Zaifu Lin, Zhaohui Meng, Hao Miao et al.

ACS Nano • 2021

Powering implanted medical devices (IMDs) is a long-term challenge since their use in biological environments requires a long-term and stable supply of power and a biocompatible and biodegradable battery system. Here, silk fibroin-based ion-exchange membranes are developed using bionics principles for reverse electrodialysis devices (REDs). Silk fibroin nanofibril (SNF) membranes are negatively and positively modified, resulting in strong cation and anion selectivity that regulates ion diffusion to generate electric power. These oppositely charged SNF membranes are assembled with Ag/AgCl electrodes into a multicompartment RED. By filling them with 10 and 0.001 mM NaCl solutions, a maximum output power density of 0.59 mW/m2 at an external loading resistance of 66 kΩ is obtained. In addition, 10 pairs of SNF membranes produce a considerable voltage of 1.58 V. This work is a proof of concept that key components of battery systems can be fabricated with protein materials. Combined with the emergence of water-based battery technologies, the findings in this study provide insights for the construction of tissue-integrated batteries for the next generation of IMDs.

Jipeng Li, Linhan Du, Xian Kong et al.

National Science Review • 2023

ABSTRACT A biological potassium channel is >1000 times more permeable to K+ than to Na+ and exhibits a giant permeation rate of ∼108 ions/s. It is a great challenge to construct artificial potassium channels with such high selectivity and ion conduction rate. Herein, we unveil a long-overlooked structural feature that underpins the ultra-high K+/Na+ selectivity. By carrying out massive molecular dynamics simulation for ion transport through carbonyl-oxygen-modified bi-layer graphene nanopores, we find that the twisted carbonyl rings enable strict potassium selectivity with a dynamic K+/Na+ selectivity ratio of 1295 and a K+ conduction rate of 3.5 × 107 ions/s, approaching those of the biological counterparts. Intriguingly, atomic trajectories of K+ permeation events suggest a dual-ion transport mode, i.e. two like-charged potassium ions are successively captured by the nanopores in the graphene bi-layer and are interconnected by sharing one or two interlayer water molecules. The dual-ion behavior allows rapid release of the exiting potassium ion via a soft knock-on mechanism, which has previously been found only in biological ion channels. As a proof-of-concept utilization of this discovery, we propose a novel way for ionic power generation by mixing KCl and NaCl solutions through the bi-layer graphene nanopores, termed potassium-permselectivity enabled osmotic power generation (PoPee-OPG). Theoretically, the biomimetic device achieves a very high power density of >1000 W/m2 with graphene sheets of <1% porosity. This study provides a blueprint for artificial potassium channels and thus paves the way toward next-generation electric-eel-mimetic ionic power generation.

L. Wey, P. Bombelli, Xiaolong Chen et al.

ChemElectroChem • 2019

Abstract Biophotovoltaic systems (BPVs) resemble microbial fuel cells, but utilise oxygenic photosynthetic microorganisms associated with an anode to generate an extracellular electrical current, which is stimulated by illumination. Study and exploitation of BPVs have come a long way over the last few decades, having benefited from several generations of electrode development and improvements in wiring schemes. Power densities of up to 0.5 W m−2 and the powering of small electrical devices such as a digital clock have been reported. Improvements in standardisation have meant that this biophotoelectrochemical phenomenon can be further exploited to address biological questions relating to the organisms. Here, we aim to provide both biologists and electrochemists with a review of the progress of BPV development with a focus on biological materials, electrode design and interfacial wiring considerations, and propose steps for driving the field forward.

Ahmad Nikoobakht, Jamshid Aghaei

IET Renewable Power Generation • 2017

<jats:p>This study investigates the application of a robust method to solve the problem of security constrained unit commitment (SCUC) with flexible resources for managing the uncertainty of significant wind power generation (WPG) to sustain the load‐generation balance. The flexible resources include up/down ramping capability of thermal units, hourly demand response, energy storage system and transmission switching action through an integrated scheme. The application of mixed‐integer linear programming to deal with the SCUC problem with flexibility resources has been discussed in this study using information‐gap decision theory (IGDT) to realise a robust strategy for power system decision maker. Besides, this study proposes an effective solution strategy based on Benders' decomposition to solve the proposed problem. Numerical simulation results on the modified six‐bus system and IEEE 118‐bus system clearly demonstrate the benefits of applying flexibility resources for managing the WPG uncertainty and validate the applicability of the proposed IGDT‐based SCUC model.</jats:p>

Anugerah Widiyanto, Seizo Kato, Naoki Maruyama

2002 International Joint Power Generation Conference • 2002

<jats:p>A deterministic quantitative model has been developed for use to compare the technical, economical and environment feature of various electric power generating plants. The model, which is based on matrix operations, is used in evaluating the various aspects of energy sources available for the electricity generation systems in a developing country. Several energy sources are chosen which could be considered for production of electricity to meet current and future electricity demands. A complete set of energy sources will include fossil fuel fired power plants, nuclear power plants, and natural-renewable energy power plants. A customized computer code is developed to evaluate the overall function for each system from the performance corresponding to the selected energy attributes includes five area of concerns; energy economy, energy security, environmental protection, socio-economic development and technological aspects for the electric power generations. The model developed in this study is applied to the Indonesian’s electric power sector development. Most of the data required for the model application are obtained from various sources related to power industry in Indonesia, such as the Electricity Generating Authority of Indonesia (Perusahaan Listrik Negara, PLN), Government of Indonesia, World Bank, Asian Development Bank, United Nations, and other sources, both in published and public domains. The optimization technique is kept flexible so that it can accommodate other attributes that will be found to be important according to the decision maker’s preference. By so doing, the model virtually can be used to attack any decision problem with various different attributes to reach an optimal decision concerning the selection of energy sources for electricity generation. The result of this study will be a rank of energy sources for Indonesia power generation systems based on the composite distance of each alternative to the designated optimal source of energy.</jats:p>

Jaron J. Peck, Amanda D. Smith

ASME 2015 Power Conference • 2015

<jats:p>Climate change can have a large effect on thermoelectric power generation. Typical thermoelectric power plants rely on water to cool steam in the condenser in order to produce electricity. Increasing global temperatures can increase average water temperatures as well as decrease the amount of water available for cooling due to evaporation. It is important to know how these parameters can affect power generation and efficiency of power systems, especially when assessing the water needs of a plant for a desired power output and whether a site can fulfill those needs. This paper explains the development of a model that shows how power and efficiency are affected due to changing water temperature and water availability for plants operating on a Rankine cycle. Both a general model of the simple Rankine cycle as well as modifications for regeneration and feedwater heating are presented. Power plants are analyzed for two different types of cooling systems: once-through cooling and closed circuit cooling with a cooling tower. Generally, rising temperatures in cooling water have been found to lower power generation and efficiency. Here, we present a method for quantifying power output and efficiency reductions due to changes in cooling water flow rates or water temperatures. Using specified plant parameters, such as boiler temperature and pressure, power and efficiency are modeled over a 5°C temperature range of inlet cooling water. It was found that over this temperature range, power decrease ranged from 2–3.5% for once through cooling systems, depending on the power system, and 0.7% for plants with closed circuit cooling. This shows that once-through systems are more vulnerable to changing temperatures than cooling tower systems. The model is also applied to Carbon Plant, a coal fired power plant in Utah that withdraws water from the Price River, to show how power and efficiency change as the temperature of the water changes using USGS data obtained for the Price River. The model can be applied to other thermoelectric power stations, whether actual or proposed, to investigate the effects of water conditions on projected power output and plant efficiency.</jats:p>

Xun Suo, Shuqiang Zhao, Yanfeng Ma et al.

IET Renewable Power Generation • 2023

<jats:title>Abstract</jats:title><jats:p>Aiming at the problem of multi‐point power source layout planning for power systems, the output characteristics of a power system composed of wind power, photovoltaic power, hydropower, traditional thermal power, concentrated solar power and electrochemical energy storage are comprehensively analyzed. A power source multi‐point layout planning model for a power system based on complex adaptive system theory is proposed with a focus on the complementarity among these different energies and the combination of power optimization planning and complex adaptive system theory. With the minimum construction unit of various types of power sources as the ‘agent’, considering the interactions among agents and the accumulation of experiences, the behaviour rules of the model are constantly changed, the grid‐connected positions of various types of power sources are adjusted, and the optimal layout schemes for all kinds of power capacities for each node are obtained. In addition, an agent modelling method based on complex phenomena emergence with simple rules is proposed, which reveals the core idea of the complex adaptive system theory: adaptability creates complexity. Taking the new energy construction base in Northwest China as an example, the proposed method is verified to have a significant effect on improving energy consumption in the new system. Based on the current power capacity layout and the future grid structure in this area, the future power optimization scheme is determined, and it provides guiding significance for actual engineering construction.</jats:p>

Peng Cheng, Tao Pan, Ruiye Li et al.

IET Renewable Power Generation • 2022

<jats:title>Abstract</jats:title><jats:p>In order to realize the comprehensive utilization of multiple energy sources in renewable energy ships and improve the utilization rate of renewable energy and system economy, this paper studies the matching and optimization of renewable energy power generation system and ship power system. Firstly, the structure of renewable energy ship power system is introduced. Considering the natural conditions and the actual situation of the ship for the first time, the wind power generation, photovoltaic power generation and energy storage devices are configured in the ship power system. The objective function including system annual average cost and system reliability index is established. The constraint conditions are determined, and the system energy scheduling strategy is proposed. Then, the influence of the introduction of renewable energy generation system and energy storage device on the ship power system is analyzed. Finally, particle swarm optimization and improved algorithm are used to optimize and solve the configuration problem. The relationship between the loss of power supply probability and energy excess percentage in ship power system is analyzed for the first time, which provides a reference for the optimal allocation scheme of actual ship. The results are helpful to improve the economy and system reliability of renewable energy ships.</jats:p>

Alireza Askarzadeh

IET Renewable Power Generation • 2017

<jats:p>The main contributions of this study are to (i) incorporate tidal power into a hybrid PV/wind/battery renewable energy system and (ii) introduce a new metaheuristic technique named crow search algorithm (CSA) for optimisation of the PV/wind/tidal/battery system. For this aim, power equations of the different components are introduced and an objective function is defined based on the economic analysis of the system. The proposed CSA is then used to optimally size the PV/wind/tidal/battery system. On the case study, simulation results show that using tidal energy decreases the total cost of the system. Moreover, the proposed CSA produces better results in comparison with two well‐known metaheuristic methods, namely, particle swarm optimisation and genetic algorithm in terms of accuracy and run time.</jats:p>

Selin Arslan, Bojan Mitrovic, Michael R. Muller

2002 International Joint Power Generation Conference • 2002

<jats:p>The purpose of this paper is to study vortex tube performance characteristics and the use of vortex tubes to increase the total efficiency of power systems, especially micropower systems. A vortex tube is a device in which compressed air is made to swirl and separate into two low-pressure streams, one with higher temperature than the entry and the other lower. The lack of moving parts and electricity make the vortex tube attractive for a number of specialized applications where simplicity, robustness and reliability are desired. Vortex tubes are currently used for industrial cooling applications, separation technologies, and chemical analysis. It is well known that the temperature difference between the hot and cold sides of the vortex tube scales with the pressure drop. Also, at any pressure drop, the temperatures and flow rates are dependent on the flow fractions between the hot and cold sides. Data is available for large pressure drops, but this paper presents experimental results at low-pressure drops optimizing the operational modes for various applications. The micro-power systems under consideration include micro-turbines, which evolved out of automotive turbocharger technology. The use of vortex tubes in power systems has received some attention but the use of both the hot and cold streams has never been considered. In this work, we consider such dual use. As an example of an application, the vortex tube is considered in conjunction with a heat recovery steam generator (HRSG). The vortex tube splits the turbine exhaust flow into hotter and cooler streams. The cooler stream is still hot enough to supply all needed heat in the economizer section, leaving the hotter stream to increase the exit temperature from the superheater. In this way both the air leaving the HRSG and going to the steam turbine will have an increased enthalpy and cycle efficiencies are improved. In addition, steam turbine exit quality is increased.</jats:p>

Christopher Mullen, Soobum Lee

Volume 2: Modeling, Simulation and Control; Bio-Inspired Smart Materials and Systems; Energy Harvesting • 2016

<jats:p>Energy harvesting technology can provide a renewable, portable power source for soldiers who rely solely on battery power in the field. Electromagnetic energy harvesters scavenge energy from wasted kinematic and vibration energy in human motion. The motion of interest in this paper is vertical hip displacement during human gait that acts as a base excitation. The placement of a permanent magnet based linear generator mounted in a backpack can make use of this excitation that results in relative motion of the magnet to the coil of copper wire, which induces an electric current. This current can be used to charge a battery or capacitor bank installed on the backpack to power portable electronic devices, thereby reducing the need for extra batteries and overall battery weight. The purpose of this research is to use a multi-variable optimization algorithm to identify an optimal coil and magnet layout for power maximization. Results from this study will pave the way for a more efficient energy harvesting backpack while providing better insight into the efficiency of magnet and coil layout for various applications for electromagnetic power generation from vibration.</jats:p>

Mohammed Lamine Mekhalfia

Energy Harvesting and Systems • 2021

<jats:title>Abstract</jats:title> <jats:p>Thermal Energy harvesting intends to supply portable or wireline electrical appliances connected to a generator with the necessary power on the purpose of making them energy-independent. The implemented power values in this case are small; they range from Microwatt to Watt. This self-feeding process is an attempt to cope with the widespread energy-efficient electronic technologies of nowadays. Additionally, this study aims at recovering renewable micro-energy by means of the piezoelectric material and optimizing its efficiency by using Shape Memory Alloys (SMAs). This study sheds light upon the progress made on storage devices that are necessary to compensate for the intermittencies and the inadequacies that occur in the production and consumption of the generated electrical energy.</jats:p>

Jun Wei, Lian Duan

Volume 2: Integrated System Design and Implementation; Structural Health Monitoring; Bioinspired Smart Materials and Systems; Energy Harvesting • 2015

<jats:p>A class of piezoelectric-based rotary electrical-energy generator is presented in which a polygon-shaped gear is used to effectively couple the rotating shaft with multiple piezoelectric cantilevers. The relation between the input rotational speed and the output power production for a laboratory-scale device with an octagonal gear is systematically characterized both by experiments with DC-motor controlled rotation inputs and by finite-element analyses (FEA) with prescribed gear rotational speeds. The electric signals generated by each piezoelectric bimorph are shown in phase with each other as well as the total power output scales with the number of piezoelectric bimorphs. The generator outputs higher electric power over a significantly wider range of rotational frequencies than similar devices do using the piezoelectric transduction mechanism. The generated power increases almost linearly with the input rotational speed for input frequencies up to at least 300 RPM. The broadband feature of the present generator makes it ideal for power generation systems that operate with low frequent, broadband excitations like those that harvest energy from wind and tidal flows.</jats:p>

Sayem Zafar, Mohamed Gadalla

Volume 6B: Energy • 2015

<jats:p>A renewable energy harvesting system is designed and tested for micro power generation. Such systems have applications ranging from mobile use to off-grid remote applications. This study analyzed the use of micro power generation for small unmanned aerial vehicle (UAV) flight operations. The renewable energy harvesting system consisted of a small wind turbine, flexible type PV panels and a small fuel cell. Fuel cell is considered the stable source while PV and wind turbine produced varying power output. The load of around 250 W is simulated by a small motor. The micro wind turbine with the total length of 4.5 m and the disk diameter of 1.8 m is tested. The micro wind turbine dimensions make it big enough to be used to charge batteries yet small enough to be installed on rooftops or easily transportable. The wind turbine blades are installed at an angle of 22°, with respect to the disk plane, as it gives the highest rotation. The voltage and current output for the corresponding RPM and wind speeds are recorded for the wind turbine. Two 2 m and a single 1 m long WaveSol Light PV panels are tested. The PV tests are conducted to get the current and voltage output with respect to the solar flux. The variation in solar flux represented the time of day and seasons. A 250 W PEM fuel cell is tested to run the desired load. Fuel cell’s hydrogen pressure drop is recorded against the output electrical power and the run time is recorded. System performance is evaluated under different operating and environmental conditions. Data is collected for a wide range of conditions to analyze the usability of renewable energy harvesting system. This energy harvesting method significantly improves the usability and output of the renewable energy sources. It also shows that small renewable energy systems have existing applications.</jats:p>

Babak Mikaeeli Kangarshahi, Seyed Morteza Naghib, Davood Younesian et al.

Advanced Functional Materials • 2025

<jats:title>Abstract</jats:title><jats:p>Bacterial cellulose is a biodegradable and ecologically safe material that has the potential to convert mechanical vibrations into electrical energy. This review introduces green energy harvesting, a novel concept that harnesses natural processes to provide sustainable energy. A thorough overview of bacterial cellulose, covering its distinctive features, its biological origin, and its energy conversion process, is fully presented. The different materials and methods used to design and fabricate bacterial cellulose‐based energy harvesters are explored. Moreover, the various applications and benefits of these devices in the context of renewable energy are examined. The current challenges and limitations of this emerging field are identified and the possible avenues for future research are suggested. The significance of adopting eco‐friendly approaches in achieving a balance between human needs and environmental preservation is highlighted. By providing a comprehensive and critical assessment of bacterial cellulose as a green energy harvester, this review aims to motivate researchers, engineers, and policymakers to tap into the rhythmic potential of this natural material in building a more sustainable and resilient future.</jats:p>

João Vitorino, Bruno Damas, Vítor Víegas

Energy Harvesting and Systems • 2024

<jats:title>Abstract</jats:title> <jats:p>There is an increasing dependence on electronic devices in the battlefield, including equipment for communications, positioning and navigation, and combat situation awareness. These devices are usually powered by batteries because they are reliable and have good power density (energy per kilogram). Nevertheless, batteries are heavy and bulky, which reduces agility and increases fatigue of the ground troops. An alternative is to extract energy from renewable sources (like the sun and the wind) or harvest energy from the human body itself (like temperature gradients and walking). This article studies the feasibility of a piezoelectric generator, stimulated by human gait, to power electronic devices on the battlefield. Tests were carried out to measure the energy harvested from several piezoelectric ceramics placed under the sole of a soldier’s boot. Different materials and arrangements were tried to maximize the power, leading to the development of a prototype. The prototype was able to harvest 875 <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="graphic/j_ehs-2023-0149_eq_001.png"/> <m:math xmlns:m="http://www.w3.org/1998/Math/MathML"> <m:mi mathvariant="normal">μ</m:mi> <m:mi mathvariant="normal">J</m:mi> </m:math> <jats:tex-math>{\rm{\mu }}{\rm{J}}</jats:tex-math> </jats:alternatives> </jats:inline-formula> on each step, on average. Walking 1 h, at a pace of 40 steps/min, leads to 2.1 J of energy, enough to supply a 3.3 V device consuming 10 mA for around a minute. These results are interesting for any situation that requires emergency power on the battlefield (e.g., trigger a device, call for rescue, acquire localization).</jats:p>

Mihail O. Cernaianu, Aurel Gontean

Advances in Environmental Engineering and Green Technologies • 2015

<jats:p>The authors propose in this chapter an original, self-sustainable, power supply system for wireless monitoring applications that is powered from an energy harvesting device based on thermoelectric generators (TEGs). The energy harvesting system's purpose is to gather the waste heat from low temperature sources (&lt;90°C), convert it to electrical energy and store it into rechargeable batteries. The energy harvesting system must be able to power a so-called condition monitoring system (CMS) that is used for the monitoring of heat dissipation equipment. The setup used for measurements (including mechanical details) and the experiments are described along with all the essential results of the research. The electronic system design is emphasized and various options are discussed.</jats:p>

Mingyi Liu, Wei-Che Tai, Lei Zuo

Volume 2: Mechanics and Behavior of Active Materials; Structural Health Monitoring; Bioinspired Smart Materials and Systems; Energy Harvesting; Emerging Technologies • 2018

<jats:p>Portable, wearable, and mobile devices are becoming more and more popular in the past two decades. Those devices rely on batteries heavily as power source. However, the limited life span of batteries constitutes a limitation. Human body energy harvesting has the potential to power those devices, thus replacing batteries or extending battery life. Harvesting positive muscle work from human body can be a burden, and exhausts the wearer. In this paper, we developed a biomechanical energy-harvesting device that generates electricity by harvesting negative work during human walking. The energy harvester mounts on the ankle and selectively engages to generate power between the middle stance phase and terminal stance phase, during which the calf muscles do negative work. The device harvests negative energy by assisting muscles in performing negative work. Test subjects walking with the device produced an average of 0.94 watts of electric power. From treadmill test, the device was shown to harvest energy only during the negative work phase, as a result it has the potential to not to increase the metabolic cost. Producing substantial electricity without burden on the wearer makes this harvester well suited for powering wearable, portable, and mobile devices.</jats:p>

Sohang Kundu, Reshmi Dani, Nancy Makri

Science Advances • 2022

<jats:p> The efficient, directional transfer of absorbed solar energy between photosynthetic light-harvesting complexes continues to pose intriguing questions. In this work, we identify the pathways of energy flow between the B800 and B850 rings in the LH2 complex of <jats:italic>Rhodopseudomonas molischianum</jats:italic> using fully quantum mechanical path integral methods to simulate the excited-state dynamics of the 24 bacteriochlorophyll molecules and their coupling to 50 normal mode vibrations in each chromophore. While all pigments are identical, the tighter packing of the inner B850 ring is responsible for the thermodynamic stabilization of the inner ring. Molecular vibrations enable the 1-ps flow of energy to the B850 states, which would otherwise be kinetically inaccessible. A classical treatment of the vibrations leads to uniform equilibrium distribution of the excitation, with only 67% transferred to the inner ring. However, spontaneous fluctuations associated with the quantum motion of the nuclei increase the transfer efficiency to 90%. </jats:p>

D. Buczynska, Ł. Bujak, M. A. Loi et al.

Applied Physics Letters • 2012

<jats:p>Energy transfer from a conjugated polymer blend (poly(9,9-dioctylfluorenyl-2,7-diyl):poly (2-methoxy-5-(2-ethylhexyloxy)-1, 4-phenylenevinylene) to a light-harvesting complex 2 from purple bacteria has been demonstrated using time-resolved fluorescence spectroscopy. For our hybrid nanostructure, we observe a 30% reduction of the fluorescence lifetime of the polymer emission as compared to the pure polymer layer. This result is an important step towards integrating naturally evolved biomolecules with synthetic materials into biohybrid organic electronic systems.</jats:p>

Renata Toczyłowska-Mamińska, M. Mamiński

Energies • 2022

An underappreciated source of renewable energy is wastewater, both municipal and industrial, with global production exceeding 900 km3 a year. Wastewater is currently perceived as a waste that needs to be treated via energy-consuming processes. However, in the current environmental nexus, traditional wastewater treatment uses 1700–5100 TWh of energy on a global scale. The application of modern and innovative treatment techniques, such as microbial fuel cells (MFC), would allow the conversion of wastewater’s chemical energy into electricity without external energy input. It has been demonstrated that the chemically bound energy in globally produced wastewater exceeds 2.5 × 104 TWh, which is sufficient to meet Europe’s annual energy demand. The aim of this paper is to answer the following questions. How much energy is bound in municipal and industrial wastewaters? How much of that energy can be extracted? What benefits will result from alternative techniques of waste treatment? The main finding of this report is that currently achieved energy recovery efficiencies with the use of microbial fuel cells technology can save about 20% of the chemical energy bound in wastewater, which is 5000 TWh on a global scale. The recovery of energy from wastewater via MFC technology can reach as much as 15% of global energy demands.

Chunjun Zhan, Xiaowei Li, Yankun Yang et al.

Biotechnology and Bioengineering • 2021

As alternatives to traditional fermentation substrates, methanol (CH3OH), carbon dioxide (CO2) and methane (CH4) represent promising one‐carbon (C1) sources that are readily available at low‐cost and share similar metabolic pathway. Of these C1 compounds, methanol is used as a carbon and energy source by native methylotrophs, and can be obtained from CO2 and CH4 by chemical catalysis. Therefore, constructing and rewiring methanol utilization pathways may enable the use of one‐carbon sources for microbial fermentations. Recent bioengineering efforts have shown that both native and nonnative methylotrophic organisms can be engineered to convert methanol, together with other carbon sources, into biofuels and other commodity chemicals. However, many challenges remain and must be overcome before industrial‐scale bioprocessing can be established using these engineered cell refineries. Here, we provide a comprehensive summary and comparison of methanol metabolic pathways from different methylotrophs, followed by a review of recent progress in engineering methanol metabolic pathways in vitro and in vivo to produce chemicals. We discuss the major challenges associated with establishing efficient methanol metabolic pathways in microbial cells, and propose improved designs for future engineering.

Peter Q Fischer, I. Sánchez-Andrea, A. Stams et al.

Environmental Microbiology • 2021

Summary Methanol is an ubiquitous compound that plays a role in microbial processes as a carbon and energy source, intermediate in metabolic processes or as end product in fermentation. In anoxic environments, methanol can act as the sole carbon and energy source for several guilds of microorganisms: sulfate‐reducing microorganisms, nitrate‐reducing microorganisms, acetogens and methanogens. In marine sediments, these guilds compete for methanol as their common substrate, employing different biochemical pathways. In this review, we will give an overview of current knowledge of the various ways in which methanol reaches marine sediments, the ecology of microorganisms capable of utilizing methanol and their metabolism. Furthermore, through a metagenomic analysis, we shed light on the unknown diversity of methanol utilizers in marine sediments which is yet to be explored.

Nur Shahirah Mohd. Aripen Zuraidah Rasep, Amelia Md. Som Aida Safina Arida, Norilhamiah Yahya Mohd. Syazwan Mohd. Ghazali

Journal of Environmental Science and Technology • 2016

Microbial Fuel Cell (MFC) is a bio-electrochemical system that drives a current by using bacteria and mimicking bacterial interactions found in nature. This study was conducted to investigate the efficiency of MFC for electricity generation and removal of Chemical Oxygen Demand (COD). This research also study the effect of several parameters such as electrode sizes and type of microbial fuel cell on the performance of MFC. This study was carried out by using single and double chamber MFC. In effect, on electrode size, the 8×8 cm gives the highest maximum current generation which is 0.72 mA and highest COD removal efficiency of 62.96%. For effect of types MFC, single chamber microbial fuel cell gives the highest maximum current generation which is 0.78 mA and highest COD removal efficiency of 64.20%. This result shows that, MFC from food wastewater can convert chemical energy to electrical energy. DOI: 10.3923/jest.2016.481.485

Han Sun, Weiyang Zhao, Xuemei Mao et al.

Biotechnology for Biofuels • 2018

Microalgae are capable of producing sustainable bioproducts and biofuels by using carbon dioxide or other carbon substances in various cultivation modes. It is of great significance to exploit microalgae for the economical viability of biofuels and the revenues from high-value bioproducts. However, the industrial performance of microalgae is still challenged with potential conflict between cost of microalgae cultivation and revenues from them, which is mainly ascribed to the lack of comprehensive understanding of carbon metabolism and energy conversion. In this review, we provide an overview of the recent advances in carbon and energy fluxes of light-dependent reaction, Calvin–Benson–Bassham cycle, tricarboxylic acid cycle, glycolysis pathway and processes of product biosynthesis in microalgae, with focus on the increased photosynthetic and carbon efficiencies. Recent strategies for the enhanced production of bioproducts and biofuels from microalgae are discussed in detail. Approaches to alter microbial physiology by controlling light, nutrient and other environmental conditions have the advantages of increasing biomass concentration and product yield through the efficient carbon conversion. Engineering strategies by regulating carbon partitioning and energy route are capable of improving the efficiencies of photosynthesis and carbon conversion, which consequently realize high-value biomass. The coordination of carbon and energy fluxes is emerging as the potential strategy to increase efficiency of carbon fixation and product biosynthesis. To achieve more desirable high-value products, coordination of multi-stage cultivation with engineering and stress-based strategies occupies significant positions in a long term.

M. Esfandyari, D. Jafari, Hamed Azami

Biofuels • 2023

Abstract Microbial fuel cells (MFCs) have emerged as a promising technology for the sustainable wastewater treatment and simultaneous recovery of energy. MFCs enable the direct conversion of organic matter in wastewater into electricity using the metabolic activity of exoelectrogenic bacteria through a bio-electrochemical process. Several feasibility studies have demonstrated the ability of MFCs to produce electricity efficiently while treating wastewater and validated their potential application. However, further optimization is still required to address the technological and economic challenges associated with scaling up of MFC systems, such as membrane performance and capital costs. This review examines the fundamental principles and applications of MFCs for power generation and sludge remediation. Key factors which influence the MFCs’ efficiency, including electrode design and microbial communities, are also discussed. While MFCs have served as a cost-effective solution for integrated wastewater management and renewable energy recovery, additional research is needed to enhance their system designs and facilitate their commercial adoption.

Matheus Sanitá Lima, Rosymar Coutinho de Lucas

Frontiers in Microbiology • 2022

Sixty years have passed since Rachel Carson published her seminal book “Silent Spring” (Carson, 1962). Her work catapulted the ecological movement and shapedmodern environmentalism (Kroll, 2001). However, fast-forward to present day and we seem not to have paid enough attention to the environment. Guidelines for a sustainable future have been repeatedly proposed and the planetary boundaries for our safe existence have been established (Rockström et al., 2009). Yet, more than 80% of the current global energy consumption still relies on unsustainable fossil fuels1 (Ritchie and Roser, 2020) and the COP26 negotiations have not delivered (Sheather, 2021). To make things worse, the demand for oil and gas is expected to peak in the next two decades.2 The prevailing linear economy based on the take-make-dispose system is unsustainable (Sariatli, 2017) and climate change already affects biological systems around the globe (Freitas et al., 2021). There will not be a “one-stop shop” type of solution, but we need to transition to a circular economy and biorefineries are a great place to start (Ubando et al., 2020). Among several models, the lignocellulosic biorefinery concept is prominent (Silva et al., 2018) and this is where fungi occupy a special place.

Xin Zhou, Fengting Lv, Yiming Huang et al.

Chemistry – A European Journal • 2020

Bioelectrochemical systems (BESs) provide favorable opportunities for the sustainable conversion of energy from biological metabolism. Biological photovoltaics (BPVs) and microbial fuel cells (MFCs) respectively realize the conversion of renewable solar energy and bioenergy into electrical energy by utilizing electroactive biological extracellular electron transfer, however, along with this energy conversion progress, relatively poor durability and low output performance are challenges as well as opportunities. Advances in improving bio-electrode interface compatibility will help to solve the problem of insufficient performance and further have a far-reaching impact on the development of bioelectronics. Conjugated polymers (CPs) with specific optical and electrical properties (absorption and emission spectra, energy band structure and electrical conductivity) afforded by π-conjugated backbones are conducive to enhancing the electron generation and output capacity of electroactive organisms. Furthermore, the water solubility, functionality, biocompatibility and mechanical properties optimized through appropriate modification of side chain provide a more adaptive contact interface between biomaterials and electrodes. In this minireview, we summarize the prominent contributions of CPs in the aspect of augmenting the photovoltaic response of BPVs and power supply of MFCs, and specifically discussed the role of CPs with expectation to provide inspirations for the design of bioelectronic devices in the future.

M. A. Costa de Oliveira, Pedro Pablo Machado Pico, Williane da Silva Freitas et al.

Applied Sciences • 2020

In this work, we synthesized new materials based on Fe(II) phthalocyanine (FePc), urea and carbon black pearls (BP), called Fe-N-C, as electrocatalysts for the oxygen reduction reaction (ORR) in neutral solution. The electrocatalysts were prepared by combining ball-milling and pyrolysis treatments, which affected the electrochemical surface area (ECSA) and electrocatalytic activity toward ORR, and stability was evaluated by cyclic voltammetry and chronoamperometry. Ball-milling allowed us to increase the ECSA, and the ORR activity as compared to the Fe-N-C sample obtained without any ball-milling. The effect of a subsequent pyrolysis treatment after ball-milling further improved the electrocatalytic stability of the materials. The set of results indicated that combining ball-milling time and pyrolysis treatments allowed us to obtain Fe-N-C catalysts with high catalytic activity toward ORR and stability which makes them suitable for microbial fuel cell applications.

Nooruddeen Jabbar, S. Alardhi, Thaer M. Al-Jadir et al.

Journal of Ecological Engineering • 2023

Microbial fuel cells (MFCs) pertain to a kind of modern technology for the direct conversion of chemical energy in organic matter from wastewaters into electricity during the oxidation of organic substrates. A system of continuous MFC was constructed for the treatment of real petroleum refinery wastewater (PRW). The treatment of real PRW, operational performance of the MFC system, biodegradation of furfural, and energy output were investigated in this study. The MFC was inoculated by mixed anaerobic bacteria, with Bacillus sp. as the dominant type, and continuously operated for 30 days. The biodegradation of furfural and phenol, which are the most prevalent toxicants in refinery wastewater, was investigated. The MFC system reached maximum energy outputs of 552.25 mW/m 3 and 235 mV. In the anodic chamber, the maximum removal of furfural and phenol was higher than 99%, with biodegradation of organic content reaching up to 95%. This study demonstrated the viability of a continuous-flow MFC system as a green technology for the treatment of furfural-rich real refinery effluents while generating electricity.

Yu Niu, Zhiqian Wang, Yingying Xiong et al.

Molecules • 2024

By allowing coal to be converted by microorganisms into products like methane, hydrogen, methanol, ethanol, and other products, current coal deposits can be used effectively, cleanly, and sustainably. The intricacies of in situ microbial coal degradation must be understood in order to develop innovative energy production strategies and economically viable industrial microbial mining. This review covers various forms of conversion (such as the use of MECoM, which converts coal into hydrogen), stresses, and in situ use. There is ongoing discussion regarding the effectiveness of field-scale pilot testing when translated to commercial production. Assessing the applicability and long-term viability of MECoM technology will require addressing these knowledge gaps. Developing suitable nutrition plans and utilizing lab-generated data in the field are examples of this. Also, we recommend directions for future study to maximize methane production from coal. Microbial coal conversion technology needs to be successful in order to be resolved and to be a viable, sustainable energy source.

Surbhi Jain, James K. Heffernan, Jitendra A. Joshi et al.

Microbiology Australia • 2023

Climate change and food security are two of our most significant global challenges of our time. Conventional approaches for food production not only produce greenhouse gases but also require extensive land and water resources. An alternative is to use gas fermentation to convert greenhouse gases as feedstocks into microbial protein-rich biomass (single-cell protein). Aerobic methanotrophic (methane-oxidising) and hydrogenotrophic (hydrogen-oxidising) bacteria, which produce biomass using gases as their energy and carbon sources, are ideal candidates for single-cell protein production. However, multiple innovations are required for single-cell protein production to be economical and sustainable. Although current technologies rely on conversion of purified single gaseous substrates, the potential to directly use mixed gas streams from point sources remains reasonably unexplored. In addition, there is much potential to increase nutritional and commercial value of single-cell protein through synthetic biology. In this perspective, we discuss the principles, approaches, and outlook for gas fermentation technologies aiming to significantly reduce greenhouse gas emissions and enhance food security.

Swati Das, R. Raj, M. Ghangrekar

Green Chemistry • 2023

Third-generation biodiesel produced using carbon-neutral algal feedstock is a promising alternative to meet global energy demands. However, the economic viability of algae-derived biodiesel is severely impacted by poor lipid recovery...