Electric Power Generation Technologies Research Articles

Renewable Energy Integration in Bangladesh: Opportunities and Challenges for Thermoelectric and Thermoionic Systems

This paper presents a comprehensive analysis of the potential of thermo electric and thermo ionic power generation technologies in Bangladesh, with a focus on utilizing the heat generated from industry, thermal power stations, and solar irradiance. The study assesses the current energy landscape in the country and highlights the need for alternative and sustainable sources of energy to meet the increasing demand. The paper reviews the relevant literature and discusses the principles and working mechanisms of thermo electric and thermo ionic power generation technologies. It also examines the feasibility of these technologies in the context of Bangladesh and provides recommendations for their implementation. The paper concludes that thermo electric and thermo ionic power generation have the potential to significantly contribute to the country's energy mix, reduce its dependence on non-renewable sources, and promote sustainable development. The recommendations offered in this study are expected to help policymakers, industry stakeholders, and researchers in making informed decisions towards a sustainable and resilient energy future in Bangladesh.

Electric power generation technology of natural gas pressure reduction: Insights from black box-gray box hierarchical exergy analysis and evaluation method

Based on the “three box” exergy analysis model, a black box-gray box hierarchical exergy analysis and evaluation method is put forward in this paper, which is applied to evaluate the power generation technology of differential pressure produced by natural gas expansion. By using the exergy analysis theory, the black box - gray box hierarchical exergy analysis models of three differential pressure power generation technologies are established respectively. Firstly, the “black box” analysis models of main energy consuming equipment are established, and then the “gray box” analysis model of the total system is established. Based on the calculation results of exergy analysis indexes, the weak energy consumption equipment in the whole power generation process is accurately located. Taking a gas field in southwest China as an example, the comprehensive energy consumption evaluation of the three power generation technologies is carried out, and the technology with the best energy consumption condition among the three technologies is determined. Finally, the rationalization improvement measures are put forward from improving the air tightness, replacing the deflector and reducing the flow loss.

Power Generation from Moisture Fluctuations Using Polyvinyl Alcohol-Wrapped Dopamine/Polyvinylidene Difluoride Nanofibers.

Despite the boom in the water-triggered electric power generation technologies, few attempts have been made with a broader horizonyielding the electricity from sweat, which is of great value for low-power-consumption wearable electronics. Here, an electromechanical coupling and humidity-actuated two-in-one humidity actuator-driven piezoelectric generator (HAPG) are reported, that can yield continuous electric power from fluctuations in the ambient humidity. It is composed of polyvinyl alcohol (PVA)-wrapped highly aligned dopamine (DA)/polyvinylidene fluoride (PVDF) shell/core nanofibers (PVA@DA/PVDF NFs). As-received PVA@DA/PVDF NFs can exchange water with the ambient humidity to perform expansion and contraction and convert them into electric power. An all-fiber-based portable HAPG is fabricated and tested on human palm skin. The devices show high sensitivity and accuracy for converting the mental sweating-derived continuous moisture fluctuations into electric power. This electric power can be stored in capacitors, which is expected to power micro- and nano-electronic devices or be used in electrotherapy such as electrical stimulation to promote wound healing. Beyond this, the obtained voltage profiles exhibit unique features that can reflect the typical sweat damping oscillation curve features.

Comparison of Different Synthesis Methods to Obtain GDC as Nanoparticulated Electrolytic Material for SOFCs Operating at Intermediate Temperature (~500°C)

The necessary global electrical energy demand employs a high amount of fossil fuels and produces emissions of polluting gases due to its combustion, which needs the improving of the electric power generation technologies friendlier with the environment. This technology must guarantee to be sustainable, economic and available for all people. The SOFCs represent a promising alternative in the production of electrical energy directly from chemical energy through a series of electrochemical reactions with the use of fuels as hydrogen, carbon monoxide, methane and several synthesis gases rich in hydrogen or methane.The development of SOFCs has several challenges, related with thermic and electrochemical properties of the materials that constitutes anode, cathode and electrolyte. Several materials has been tested, for instance perovskites, aiming for facilitate the ionic conductivity inside these cells and reduce the operating temperatures, also looking for the increase of performance. To get similar thermal expansion coefficients (TEC) in anode, electrolyte and cathode, researchers have tested different chemical compositions to modify the perovskite structure of materials utilized in these components for SOFCs. Specifically for the electrolyte, these modifications could enhance the creation of oxygen vacancies, contributing to decrease TEC and also reduce the cathodic polarization, which are IT-SOFC operating challenges.Aiming for solve these issues, in this work, the synthesis of a cobaltite of lanthanum type perovskite LSCF, as cathode material, is developed by the co-precipitation method, using nitrate precursors. Also GDC is synthetized by three synthesis methods, which is the main purpose of this work: co-precipitation, sol-gel combustion (SGC) and hydrothermal. The obtained compounds are characterized physical and chemically by FTIR, TGA, TEM, SEM-EDS, and XRD.GDC synthesis was carried out by three different synthesis routes (SGC, Hydrothermal and Co-precipitation). The analysis of the mapping with EDS showed the uniform presence of each of the components Ce, Gd and O in the entire sample, in all the studied cases. In addition, the chemical composition in weight percent (% wt) by zones was evaluated to delimit the compositional homogeneity of the sample, but two different compositions were found that were replicated in all the extent of the powder, (1) Ce0,8Gd0,2O1,9 and (2) Ce0,7Gd0,3O1,85, as possible, which was corroborated with XRD analysis, in addition, the sample is crystalline and organized, the crystallinity decreases as follows SGC> Co-precipitation> Hydrothermal; this is defined as well, since the peaks are more defined and narrow in that order, whereas powders obtained by SGC are considered more crystalline than those obtained by the other two routes. Furthermore, similar stoichiometries of these compounds can be used in this type of fuel cell, since both have been used before.In all the cases studied, FTIR analysis show the characteristic adsorption band of GDC, which is normally at 565 cm-1, and is assigned to vibrations by elongation between metal and oxygen, which in this case would be the Ce bonds, -O and / or Gd-O. On the other hand, with TEM analysis corroborate that all the powders obtained with GDC synthesis have a nanometric size. The particle size obtained in decreasing order was SGC> Co-precipitation> Hydrothermal.The obtained results in this work show that GDC electrolytes are dependent of the synthesis route, but in general have adequate physical and chemical properties to be applied with good performance in IT-SOFCs. Considering this, currently we are building a single IT-SOFC with these materials to test at 500°C.

Challenges and opportunities of deploying nuclear technology for electric power generation in Kenya

Challenges and opportunities of deploying nuclear technology for electric power generation in Kenya

Advanced petroleum coke oxy‐combustion power generation with carbon capture and sequestration: Part II—Environmental assessment and cost of CO2 avoided

AbstractThe life‐cycle environmental impact assessment and cost of the CO2 avoided (CCA) of a petroleum coke oxy‐combustion electric power generation technology operated with and without carbon capture and sequestration (CCS) are discussed. In an extension of our work on the design and economics presented in Part I, the environmental assessment was carried out for three candidate petroleum coke oxy‐combustion designs: petcoke oxy‐combustion operated without carbon capture and sequestration (CCS); petcoke oxy‐combustion operated with CCS; and petcoke oxy‐combustion with CO2 purification by distillation and CCS. The environmental life‐cycle assessment of the designs was computed using both TRACI 2.1 midpoint and ReCiPe 2016 midpoint and endpoint methods. Using a levelized cost of electricity, the CCA was also employed as a performance metric for each of the designs. The results showed a life‐cycle GWP of 1089 kgCO2eq/MWh, 17.32 kgCO2eq/MWh, and 75.65 kgCO2eq/MWh for the petcoke oxy‐combustion design operated without CCS, petcoke oxy‐combustion design operated with CCS, and petcoke oxy‐combustion with CO2 purification by distillation and CCS, respectively. It was also found that acidification potential and particulate matter emissions were higher for the petcoke oxy‐combustion design operated without CCS due to the venting of SO2 to the atmosphere. With a levelized cost of electricity between $90.94/MWh and $102.8/MWh, the CCA of the CCS‐enabled designs were between $10.43/tCO2eq and $24.35/tCO2eq, which is competitive with most other carbon capture options for large‐scale fossil‐based power plants. When the cost parameters were varied at the worst‐case scenario, the highest CCA observed was $115.9/tCO2eq.

Advanced petroleum coke oxy‐combustion power generation with carbon capture and sequestration: Part I—Design and techno‐economic analysis

AbstractThis study presents a first‐of‐its‐kind design and economic analysis of a petroleum coke oxy‐combustion electric power generation technology operated with and without carbon capture and sequestration. In this work, we examined three petroleum coke oxy‐combustion designs: petcoke oxy‐combustion, petcoke oxy‐combustion operated with carbon capture and sequestration (CCS), and petcoke oxy‐combustion with CO2 purification by distillation and CCS. The technical and economic performance of the designs were assessed based on thermal efficiency, CO2 capture rate, pipeline CO2 purity, CO2 emissions, and levelized cost of electricity (LCOE). The results of our assessments yielded a base‐case LCOE of $84.24/MWh for the petcoke oxy‐combustion design, $90.94/MWh for the petcoke oxy‐combustion design operated with CCS, and $102.8/MWh for petcoke oxy‐combustion with CO2 purification by distillation and CCS. Although the design that employed CO2 purification had higher LCOE than the other designs, its captured CO2 stream meets pipeline standards. Therefore, this design was selected for the proposed petroleum coke oxy‐combustion technology. Further analysis carried out includes the cradle‐to‐customer gate life‐cycle environmental impact assessment of the petcoke oxy‐combustion power plant which is presented in Part II of this work. Thus, this work represents the first study to present the eco‐technoeconomic and life‐cycle analysis that considered the impacts of O2 removal from CO2 captured from oxy‐combustion exhaust via cryogenic distillation for solid fuels in general.

A Part II of the Reports on the Ongoing HMD Technology Research

The report continues reporting of results of an ongoing research verifying a hypothetic energy generation mechanism for reengineering of Gritskevich’s Hydro Magnetic Dynamo (HMD). The HMD technology is a patented technology for electric power generation. It was invented in Russia and deployed in a semi-industrial scale (1.5 MW power unit) in Armenia in 1992. After its successful exploitation during 5 years no more units were assembled. Nowadays the technology needs verification of its physical mechanisms for its successful reengineering. The aim of the report is to present current results of an ongoing theoretical and experimental research of hypothetic physical mechanisms providing energy generation in the unit. It is written without disclosure of its construction and technical details. Thus the theory of hypothetic energy generation mechanisms is described in a general way. The reported experimental results provide only partial support for the theory. They should be independently reproduced and verified.

Evaluating electric power generation technologies: A multicriteria analysis based on the FITradeoff method

Evaluating which electric power generation technologies should comprise the electricity matrix of a country has become a worldwide issue. Multiple factors should be taken into account and issues such as those to do with social, economic and environmental aspects have to be considered in the decision process. In this paper a decision model based on the FITradeoff method is proposed in order to aid multicriteria decision making in the energy planning context. The originality of the paper comes from accommodating, in the proposed model, situations in which the available information is incomplete, when evaluating electric power generation technologies. In order to illustrate the applicability of the model, eight different electrical energy technologies that form the current Brazilian electricity matrix are evaluated under four dimensions: financial, technical, environmental and socio-economic. A sensitivity analysis was performed in order to check the robustness of the results obtained. The application of the proposed model provides information that could be used in Brazil when drawing up energy policies, thus showing the potential use of the method to solve related problems.

Review and comparative analysis of vortex generation systems for sustainable electric power production

This study presents a review and comparison on the power generation by artificial vortex approach. The basic principles of the artificial vortex theory are presented to comprehend the topic. The main characteristics of the components, working principles and features of the existing Vortex Generator Systems for the production of electricity have been discussed and compared. The literature demonstrates that there are two ways to establish the vortex updraft flow: (i) by constructing a special design of the updraft tower to yield a vertical pressure gradient along the axis of a vortex. These types of system have a high investment cost due to the tall tower, or (ii) by using an external heat source to create large temperature rise in ambient air and enhance the buoyancy forces. This integration between the vortex generation system and the wasted heat source is restricted operation in the industrial areas. Therefore, enhancement and development of the way to use a simple construction design based on the solar energy as a heat source support the technology of electricity production by artificial vortex generation. A solar based vortex power generator could be a potential technology for electric power generation, especially in the desert and rural areas.

A survey on smart power grid: frameworks, tools, security issues, and solutions

Smart power grid is referred to as the next revolutionary innovation in electric power generation, transmission, and distribution technology. Smart grids are an example of cyber physical system (CPS) and an extremely critical infrastructure. The smart grids are expected to be more secure and must have the ability of self-healing and recovery. Smart power grids are also one of the major targets for different kinds of cyber attacks, as they are now an open system network, according to the model architecture of smart power grid. This paper presents a comprehensive survey on understanding the smart power grid, its important components, different cyber security and other kinds of issues, existing methodologies and approaches for communication protocols, and architecture of smart power grids. We conclude our paper by discussing various research challenges that still exist in the literature, which provides a better understanding of the problem, the current solution space, and future research directions to defend smart power against different cyber attacks.

Novel Ceria-Lanthanum/Zirconium (LDC/ZDC/ZLDC) Based Anodes with the Incorporation of Copper Running over Biogas Fuel Cells

Biogas is a promising fuel for many clean energy applications and have propitious effect on the environment as well. Hydrocarbon fuels open up new path for the electric power generation technology in replacing conventional combustion devices with renewable sources e.g., biofuel. Active and stable anode nano catalysts are utilized to achieve sufficient advantages for solid oxide fuel cells running on biogas. In this paper, a series of ceria based anodes NixLiyCu(1-x-y)-LDC/ZDC/ZLDC (x=0, 0.2, 0.4, 0.6, 0.8, y=0.2) are synthesized via ball milling route, while nanocatalysts NixLiyCu(1-x-y) (NLC) and LDC/ZDC/ZLDC are prepared by glycerol sol-assisted synthesis and simple co-precipitation method respectively . These nanocatalysts are characterized using x-ray diffraction (XRD) to study its structural properties and thermal analyses are carried out by thermo-gravimertic analysis (TGA) and BET. To study its morphology, scanning electron microscopy is done to calculate its particle size and porosity. The performance of the solid oxide fuel cell with biogas has been studied with a 50% composition of methane. The short term sable performance has been observed without any carbon formation. Key words: ceria, lanthanum, zirconium, anode catalysts, biogas

Regional water consumption for hydro and thermal electricity generation in the United States

Water is an essential resource for most electric power generation technologies. Thermal power plants typically require a large amount of cooling water whose evaporation is regarded to be consumed. Hydropower plants result in evaporative water loss from the large surface areas of the storing reservoirs. This study estimated the regional water consumption factors (WCFs) for thermal and hydro electricity generation in the United States, because the WCFs of these power plants vary by region and water supply and demand balance are of concern in many regions. For hydropower, total WCFs were calculated using a reservoir’s surface area, state-level water evaporation, and background evapotranspiration. Then, for a multipurpose reservoir, a fraction of its WCF was allocated to hydropower generation based on the share of the economic valuation of hydroelectricity among benefits from all purposes of the reservoir. For thermal power plants, the variations in WCFs by type of cooling technology, prime mover technology, and by region were addressed. The results show that WCFs for electricity generation vary significantly by region. The generation-weighted average WCFs of thermoelectricity and hydropower are 1.25 (range of 0.18–2.0) and 16.8 (range of 0.67–1194)L/kWh, respectively, and the generation-weighted average WCF by the U.S.generation mix in 2015 is estimated at 2.18L/kWh.

Performance characterization and modelling of syngas-fed SOFCs (solid oxide fuel cells) varying fuel composition

SOFCs (solid oxide fuel cells) are a promising technology for electric power generation, because of their high efficiency and fuel flexibility. Relative to more mature technologies, they appear very competitive starting from small-scale applications. The aim of this study is to map SOFC performances varying fuel composition, reproducing gases of technical interest (biomass air and oxy-gasification, water and carbon dioxide co-electrolysis, steam methane reforming) and to provide a forecasting tool to predict performance upon the fuel composition occurring in any application. Therefore, at first commercial SOFC are tested using several fuel gas mixtures produced by means of the chosen technologies (H2, CO, CH4 molar fractions ranges are respectively 8–50%, 0–42%, 1–8%). Secondly, experimental data are used to build a mathematical tool to predict SOFC characteristic curve from the fuel composition. This result is interesting from the point of view of system-level modelling, because it allows characterizing commercial SOFCs performances in many technical applications. Forecast error is less than 1%. Because of its accuracy, the model can be implemented to assess properly SOFC performance as a consequence of any particular hybridization, whereas fuel composition falls into the range already defined.

Accomplishments, Status, and Road Map for the US Department of Energy's Fossil Energy SOFC Program

Development of electric power generation technology that efficiently and economically utilizes coal and natural gas while meeting environmental requirements is of crucial importance to the United States. The U.S. Department of Energy (DOE) Office of Fossil Energy (FE), through the National Energy Technology Laboratory (NETL), is leading the research and development of advanced Solid Oxide Fuel Cells (SOFC) as a key enabling technology. This work is being done in partnership with private industry, academia, and national laboratories. Program participants are making significant progress toward commercialization. Milestones include: the development and validation of multiple generations of engineered seal concepts, cells with low degradation and high power density, development of integrated stack and system modeling tools, and validation of low-cost stainless steel interconnect solutions. With advances in cost reduction, the program is now focused on research to improve durability and reliability, especially in an integrated realistic system context. Integrated system tests at larger scales (10-100 kWe) are yielding respectable degradation rates in the 1 to 1.5%/1,000 hrs under cost-effective operating conditions. In this presentation, these highlighted accomplishments will be reviewed along with the status of the program and a road map for the future.

Reputation Dynamics in Networks: Application to Cyber Security of Wind Farms

Wind power is becoming an increasingly important technology for electric power generation in many power systems around the world. A typical wind farm consists of a relatively large number of turbines under some form of decentralized control. In this context, a cyber-attack to wind power infrastructure may not only cause immediate physical damage to the facility in question, but may also threaten the stability of the power system in which this facility operates. In this paper, we present a novel distributed algorithm aimed at detecting cyber-attacks in a wind farm. The cyber-attacks considered take the form of adversarial manipulation of different turbine-specific control logic parameters. The proposed algorithm relies on the operational dynamics specific to wind farms namely that turbines that are relatively close are subject to similar wind patterns and hence must be in similar control states most of the time. This can be seen as a wisdom of the crowd effect: the true is the of the majority of turbines in physical proximity when only a few have been compromised. In the proposed algorithm, each turbine in the farm periodically shares information regarding their own control state with neighboring turbines through a dedicated wireless channel. We test the performance of the proposed algorithm in a simulation test-bed based on Denmark's Horns Rev wind farm. The results indicate that iterative reputation or trust re-allocation enables a distributed identification of affected turbines under a wide array of cyber-attack scenarios.

Crystal Structure, Cation Occupancy and Vacancy Ordering in Thermoelectric (1-x)SrTiO3-xLa1/3NbO3: A STEM-EELS Study

Thermoelectric energy conversion is widely recognized as a promising technology both for electric power generation in terms of waste heat recovery and for cooling of various electronic devices [1]. SrTiO3 based perovskites are among a number of candidate materials for such thermoelectric applications [2]. For the first time, we demonstrate the successful synthesis of (1-x)SrTiO3-xLa1/3NbO3 ceramics that exhibit excellent thermoelectric properties and we have used STEM-EELS in order to assess the quantitative effects of composition on the structure and properties of these materials.

CFD modelling of profiled-membrane channels for reverse electrodialysis

Reverse electrodialysis (RE) is a promising technology for electric power generation from controlled mixing of two differently concentrated salt solutions, where ion-exchange membranes are adopted for the generation of ionic currents within the system. Channel geometry strongly influences fluid flow and thus crucial phenomena such as pressure drop and concentration polarization. Profiled membranes are an alternative to the more commonly adopted net spacers and offer a number of advantages: avoiding the use of non-conductive and relatively expensive materials, reducing hydraulic losses and increasing the active membrane area. In this work, Computational Fluid Dynamic simulations were performed to predict the fluid flow and mass transfer behaviour in channels with profiled membranes for RE applications. In particular, channels equipped with pillars were simulated. The influence of channel geometry on fluid flow and concentration polarization was assessed by means of a parametric analysis for different profile geometries. The unit cell approach along with periodic boundary conditions was adopted to simulate fully developed boundary conditions. Transport equations, valid also for concentrated solutions, were obtained from the rigorous Stefan–Maxwell equation along with the assumptions of binary electrolyte and local electroneutrality. Simulation results show that, in the geometries investigated here, the pumping power consumption is much lower than in a conventional net spacer and very close to that of the empty channel, while calm zones are generated by the profiles, which may accentuate polarization phenomena.

An Expanded Cost of Electricity Model for Highly Flexible Power Plants

Cost of electricity (COE) is the most widely used metric to quantify the cost-performance trade-off involved in comparative analysis of competing electric power generation technologies. Unfortunately, the currently accepted formulation of COE is only applicable to comparisons of power plant options with the same annual electric generation (kilowatt-hours) and the same technology as defined by reliability, availability, and operability. Such a formulation does not introduce a big error into the COE analysis when the objective is simply to compare two or more base-loaded power plants of the same technology (e.g., natural gas fired gas turbine simple or combined cycle, coal fired conventional boiler steam turbine, etc.) and the same (or nearly the same) capacity. However, comparing even the same technology class power plants, especially highly flexible advanced gas turbine combined cycle units with cyclic duties, comprising a high number of daily starts and stops in addition to emissions-compliant low-load operation to accommodate the intermittent and uncertain load regimes of renewable power generation (mainly wind and solar) requires a significant overhaul of the basic COE formula. This paper develops an expanded COE formulation by incorporating crucial power plant operability and maintainability characteristics such as reliability, unrecoverable degradation, and maintenance factors as well as emissions into the mix. The core impact of duty cycle on the plant performance is handled via effective output and efficiency utilizing basic performance correction curves. The impact of plant start and load ramps on the effective performance parameters is included. Differences in reliability and total annual energy generation are handled via energy and capacity replacement terms. The resulting expanded formula, while rigorous in development and content, is still simple enough for most feasibility study type of applications. Sample calculations clearly reveal that inclusion (or omission) of one or more of these factors in the COE evaluation, however, can dramatically swing the answer from one extreme to the other in some cases.

A techno-economic analysis of tidal energy technology

The choice of which type of electrical power generation technology to adopt is driven by a number of factors including: cost of generated electricity; responsiveness of generating plant to demand; security of supply/resource availability; environmental impact; and execution risk. Within these, tidal energy is unique as a renewable technology since it has the capability of providing predictable, firm power contributing to security of supply. This predictability gives tidal energy additional value in a future electricity market. Especially one where stochastic renewable technologies contribute to a sizable component of the power supplied; and where reserve capacity is required to maintain supply during periods of non-availability. In the shorter term, in order for tidal energy to gain commercial acceptance, tidal technologies under development need to produce electricity at a competitive price. This paper examines the drivers influencing electricity pricing; current tidal energy developments, aimed at reducing capital costs; and bench-mark these against offshore wind.