Energy Utilization Mode Research Articles

Comprehensive Evaluation of Adaptability Zoning for Shallow Geothermal Energy Development and Utilization: Case of Nantong City, East Coast of China

The development of green energy sources, such as shallow geothermal energy, is one of the most important measures to reduce the environmental pollution caused by the use of traditional energy sources. At present, coastal cities in the east of the Yangtze River Delta, China, have favorable conditions for the development of shallow geothermal energy because of their abundant geothermal resources. However, the development and utilization of shallow geothermal energy are still in their infancy, and adaptability zoning is yet to be fully carried out. The study area is Nantong City, which is in the eastern coast of the Yangtze River Delta. A comprehensive analysis of the conditions of shallow geothermal energy is carried out based on the analysis of the regional geological, hydrogeological, and environmental geological conditions. The adaptability zoning index system of the groundwater source heat pump and buried pipe ground source heat pump system is then constructed, and the weight of evaluation factors is determined according to analytic hierarchy process. Finally, the adaptability zoning of shallow geothermal energy development and utilization mode is obtained by using the spatial analysis function of geographic information. The results showed that the areas with good suitability and better suitability account for 98.24% of the study area and those with good economy and better economy account for 99.67% of the study area. This method can provide reference suggestions for the orderly development and sustainable utilization of shallow geothermal energy in coastal cities in plain areas.

Review of multiple load forecasting method for integrated energy system

In order to further improve the efficiency of energy utilization, Integrated Energy Systems (IES) connect various energy systems closer, which has become an important energy utilization mode in the process of energy transition. Because the complex and variable multiple load is an important part of the new power system, the load forecasting is of great significance for the planning, operation, control, and dispatching of the new power system. In order to timely track the latest research progress of the load forecasting method and grasp the current research hotspot and the direction of load forecasting, this paper reviews the relevant research content of the forecasting methods. Firstly, a brief overview of Integrated Energy Systems and load forecasting is provided. Secondly, traditional forecasting methods based on statistical analysis and intelligent forecasting methods based on machine learning are discussed in two directions to analyze the advantages, disadvantages, and applicability of different methods. Then, the results of Integrated Energy Systemss multiple load forecasting for the past 5 years are compiled and analyzed. Finally, the Integrated Energy Systems load forecasting is summarized and looked forward.

Energy management in microgrid and multi‐microgrid

AbstractConsidered as basic structures of next‐generation energy system, environment‐friendly and flexible microgrid (MG) systems are potential solutions to address integration issues of stochastic renewable energy sources. Adaptable energy management approaches provide the possibility to construct effective and various energy interaction. The purpose of this paper is to present a problem‐oriented review of energy management in MG systems. This paper first comprehensively reviews recent research studies on MG, particularly in multi‐microgrid (MMG). Then, this paper proposes a concept of energy utilization model for energy management, which includes a discussion of modern concepts including MG, MMG along with picogrid, nanogrid and virtual power plant. And a synthetic energy management framework including stability, touch, efficiency, evenness, and resilience dimensions is proposed and formulated based on energy utilization mode. Then energy management system is illustrated from the perspectives of system function, management architecture, operation logic and data analysis, and further, a systematic four‐layer hierarchical architecture of management systems for whole MG and MMG systems is proposed. Moreover, key technologies in energy management are summarized and reviewed from the aspects of control, communication, prediction, optimization, and evaluation. Last, eight main prospects on the future trend of energy management in MG and MMG are also presented.

Parameter Optimization for Multistage Reluctance Coil Launcher With Residual Energy Recovery and Utilization Mode

Parameter Optimization for Multistage Reluctance Coil Launcher With Residual Energy Recovery and Utilization Mode

Optimization and assessment method for total energy system retrofit in the petrochemical industry considering clean energy substitution for fossil fuel

Carbon emission peak and neutrality prospect has expedited the revolution of conventional energy utilization mode, particularly in highly energy-intensive industries. The petrochemical industry bears great responsibility for energy conservation and carbon emission reduction. TES (Total Energy System) retrofit schemes in the petrochemical industry classified as REST (Retrofitting through Energy-Saving Techniques) and RSFC (Retrofitting through Substituting Fossil fuel with Clean energy) have emerged in large numbers recently. It is challenging for energy managers to optimize and assess TES retrofit schemes simultaneously and globally, once clean energy supply is involved. State-of-the-art assessment and optimization method for TES retrofitting is urgently needed. This work proposes a novel optimization and assessment method based on the exergy conversion and consumption processes to figure out the most cost-effective retrofit schemes in view of exergy analysis. The method features with the simulation of TES, the clean energy substitution for fossil fuel, the optimization of the subsystems, and the exergy efficiency assessment of retrofit schemes. The double-parallel-loop application framework is then presented, which deals with the optimization and assessment of RSFC and REST simultaneously. Combined plants of continuous catalytic reforming and aromatic extraction plants along with their matched TES are investigated. A MINLP optimization model is formulated and programmed with GAMS software. The optimal results show that the total exergy consumption decreased by 3200 kW with clean energy substitution. Sensitivity analysis explores the energy conservation benefits and exergy efficiency improvement when clean energy with different qualities and quantities substituting for fossil fuel, which provides valuable information for feasibly implementing retrofit schemes. Comparison of scenarios reveals the interacting influence between the implementation of RSFC and REST, which is significant for decision-making when multiple retrofit schemes are alternatives. Real-world case investigations demonstrate the validation and efficacy of the proposed method. The main findings of this study are significant and quantitative references for petrochemical industrial practice, which would contribute to energy conservation and carbon emission reduction in the future.

Multistage Reluctance Coil Launcher With Residual Energy Recovery and Utilization Mode

Launch efficiency has always been the focus of reluctance coil launchers research. In a traditional launch mode, the residual current in the drive coil creates a reverse force on the projectile. This is undesirable since the reverse force is in the opposite direction of movement, reducing the launch efficiency of the system. To address this problem, a multistage discharge circuit with the residual energy recovery and utilization mode is proposed in this article. As the projectile approaches the center of each stage of the drive coil, the current in the drive coil decays rapidly to zero by using the last stage capacitor to absorb the residual energy. The residual energy from the previous stages is eventually recovered by the last stage capacitor. This capacitor with residual energy is used to power the last stage drive coil of the reluctance coil launcher. This mode effectively suppresses the reverse force on the projectile and realizes the reuse of residual energy. Taking a four-stage reluctance coil launcher as an example, this article introduces the working principle of this mode in detail. The feasibility of the model is verified by finite-element simulation and experiments. Both simulation and experimental results show that this mode performs well in the recovery and reuse of residual energy and can effectively improve the launch efficiency of system.

Joint Optimization of Planning and Operation for Integrated Electrothermal and Hydrogen Coupling System

In view of the rough modeling of hydrogen energy system, insufficient analysis of hydrogen energy utilization mode, and the lack of consideration of the multiple uncertain factors, this paper proposes a joint optimization method of planning and operation for integrated electrothermal and hydrogen coupling system (IEHS) based on multiverse optimizer algorithm (MVO) and interval linear programming method. Firstly, the frame structure of IEHS is constructed, and multiple utilization modes of hydrogen energy are analyzed. Secondly, considering the hydrogen physical characteristics, the operation model of high-pressure hydrogen storage device based on Van Deemter equation is established, and the linear model of compressor power consumption is built considering dynamic compression ratio. On this basis, the bilevel optimization model of planning and operation for IEHS is established considering multiuncertainty and multiple hydrogen energy utilization modes. The upper model realizes the capacity configuration of equipment with the goal of minimizing the total construction and operation cost within the service life. The lower model optimizes the output of each equipment with the goal of minimizing the operation cost. The example results show that MVO and interval linear programming method for solving the bilevel optimization model have the better convergence speed and convergence ability. Further, the multiple utilization modes of hydrogen energy can effectively reduce the construction and operation cost of IEHS, and accurately depicting the physical characteristics of the hydrogen storage system can increase the coordination and optimization ability of IEHS. Considering multiple uncertain factors, the optimal configuration scheme and operation cost of IEHS are more stable.

Energy-Saving Metro Train Timetable Optimization Method Based on a Dynamic Passenger Flow Distribution

The operation of metro trains with a focus on energy savings can effectively reduce operating costs and carbon emissions. Reducing traction energy consumption and increasing the utilization efficiency of regenerative braking energy are two important energy-saving approaches that are closely related to the metro train interstation running strategy and timetable. Changes in train mass caused by dynamic changes in passenger flow represent one of the important factors affecting the energy consumption and energy-saving operation of metro trains. In this study, the differences in the temporal and spatial distributions of metro line passenger flow were specifically considered, and an energy-saving metro train timetable optimization method focused on the dissipative regenerative braking energy utilization mode was studied. First, a logistic function is used to fit the passenger flow pattern of the origin-destination (OD) station pairs, and the number of passengers getting on and off at each station is derived by establishing the OD dynamic demand matrix for the entire metro line. Then, the passenger load in each station segment is calculated. Next, a timetable optimization model is established to minimize the net energy consumption based on the load difference between station segments and the train motion equation. The interstation running time and dwell time of the metro train are optimized to increase the amount of regenerative braking energy used during the overlap time between the traction and braking actions of adjacent trains in the train operation timetable. A particle swarm optimization and genetic algorithm (PSO-GA) structure is designed to solve the model. The PSO-GA structure has PSO as the main body and integrates the chromosome crossover and mutation operations of the GA into the iterative process to improve the search efficiency of the algorithm. Finally, the proposed method and model are tested based on the actual data of a metro line in Qingdao, China. The goodness of fit of the passenger flow pattern is 0.997. The energy consumption during the study period is reduced by 5169.67 kW h using the optimized timetable. The energy-saving efficiency decreases by 12.18% at a constant OD ratio during the entire travel time and by 20.23% at the same constant load for all station segments. The results of the case analysis prove the effectiveness of the proposed method and model. In addition, the energy-saving timetable can be better optimized by considering the differences in temporal and spatial distributions of dynamic passenger flow.

Ultrathin organic polymer with p-π conjugated structure for simultaneous photocatalytic disulfide bond generation and CO2 reduction

Combining photocatalytic organic reactions with CO2 reduction is an efficient solar energy utilization mode, but it is still limited by the organic species that can be matched and the low conversion. Herein, ultrathin organic polymer with p-π conjugated structure (TPP) was rationally designed and prepared, and showed a high yield of CO (15.2 mmol g−1) and conversion of SS coupled products (100%), far exceeding the organic polymer with PO structure. The enhanced photoredox activity of TPP is ascribed to the orbital interaction between the p-orbital on phosphorus and the π-orbitals of aromatic, which can accelerate the photoinduced charge carrier separation and improve the CO2 adsorption capacity. TPP can also be used for the dehydrocoupling of various benzyl mercaptans to the corresponding SS bond products. This work provides a new concept for the efficient synthesis of disulfide bonds combined with CO2 reduction in a photoreaction system.

Energy, exergy, economic and environmental analysis of a novel steam-driven vapor recompression and organic Rankine cycle intensified dividing wall column

The dividing wall column (DWC) is a typical thermal coupled distillation column to separate the ternary mixture instead of the conventional two-column sequence. However, the energy utilization of DWC is the same as the conventional distillation column with large energy consumption. The current energy intensification measures for DWC is to use the vapor recompression (VRC) technology for retrofitting the stream cycle and use organic Rankine cycle (ORC) for waste heat recovery. The large top and bottom temperature difference of DWC limits the energy and economic benefit of VRC and also the production of ORC is not high. In this paper, unlike the general electric-driven VRC and waste heat recovery to save the energy consumption of the DWC (VRC-WHRS-DWC), a novel steam-driven VRC and waste heat recovery assisted DWC (SD-VRC-WHRS-DWC) is proposed to form a new energy utilization mode of DWC. As comparison, DWC and VRC-DWC are also developed. The single- and multi-objective genetic algorithms are used to optimize the different processes. All the processes are evaluated by energy, exergy, economic and environmental (4E) analysis. The result shows the cascade utilization of the steam in steam-driven system can effectively increase the economic benefit and decrease the energy consumption of DWC with the large temperature difference between top and bottom.

Using cognition and risk to explain the intention-behavior gap on bioenergy production: Based on machine learning logistic regression method

Bioenergy production is a certain economy energy utilization mode, which is of great economic and ecological benefits. Only when pig farmers have consistent intentions and behaviors to participate in bioenergy production, can the intentions play their role in effectively predicting behaviors. Based on the machine learning logistic regression method, taking biogas produced by swine manure as an example, we explore the role of cognition and risk in bridging the intention-behavior gap in bioenergy production. Unlike previous studies, we find that for bioenergy production, a pro-environmental behavior with positive externalities, an individual's perception of environmental policy plays a better role in driving the intention-to-behavior transition than the individual's perception of bioenergy production. From the risk perspective, our results also suggest that the key factor hindering an intention to change behavior is the individual's risk preferences rather than the degree of risk associated with bioenergy production. Policy makers could consider this observed heterogeneity when it comes to aspects such as greater highlight on environmental policy advocacy, and collaboration with insurance companies to develop products for bioenergy production.

Technical Requirement Analysis of Regulation Characteristics of CSP Station with Heat Storage System

Using solar energy to generate thermal power is often called concentrating solar power (CSP), is a grid friendly clean energy utilization mode with unique development advantages. Large capacity heat storage system with relatively mature technology and low cost can be configured to ensure stable and controllable power generation. The method can be. Solar thermal power generation has become a strategic emerging industry supported by many countries around the world. Spain, the United States, India, South Africa and other countries have carried out commercial operation of power technology with solar thermal, and installed capacity is growing steadily. China has also given key support to CSP generation technology, which has been vigorously developed. As the most promising new energy technology, CSP generation from molten salt heat storage tower is one of the main technical approaches of CSP generation. The key is to store the absorbed solar heat through thermal storage materials and release it stably for a long time, so as to achieve continuous and stable power generation independent of solar radiation changes. Through analysis, this paper puts forward the key technology research and scheme of molten salt regenerative CSP generation system, promotes the research on the bidirectional relationship between CSP station and power grid, and realizes the innovation of renewable energy technology. Relevant research results and technical schemes can be popularized and applied in demonstration power stations, and can also be used for operation control of newly-built molten salt heat exchange and storage tower power stations in the future.

Management and Utilization of Urban Rail Transit Regenerative Braking Energy Based on the Bypass DC Loop

Urban rail transit (URT) has become a major energy consumer in the city and increasing the utilization rate of trains' regenerative braking energy has become an important measure to reduce traction energy consumption. In view of the drawbacks of the traditional braking energy management and utilization mode, this article proposes a new method of URT regenerative braking energy management and utilization based on bypass dc loop (BDL). An analysis is made of its functional mode and working mechanism, and then a traction network BDL topology and its control strategy based on power electronic converter are proposed. The feasibility and effectiveness are verified by the scenario analysis method. The simulation results show that the BDL can effectively improve the utilization rate of regenerative braking energy and raise local traction network voltage by scheduling the braking energy of trains over a long distance. It serves the function of an “energy saver and voltage stabilizer.” When combined with the stationary energy storage system (ESS), it not only further improves the efficiency but also reduces the charging and discharging frequency and the depth of the ESS. As a result, the service life of the ESS is extended. The research findings can provide reference for the management and utilization of URT regenerative braking energy.

Developing an equipotential line method for the optimal design of an energy station location in a district heating system

The district heating system with distributed variable-frequency speed pumps (DVFSP) can provide substantial energy savings. Moreover, the energy station location has a great impact on the capital expenditure of heating system. Therefore, to determine the optimal energy station location in DVFSP system, this paper initially built a theoretical model of a DVFSP district heating system based on a cost-oriented index. Subsequently, an equipotential line method was illustrated and applied to a case study. This novel method can intuitively present the district distribution of the relative cost (RCnetwork) of DVFSP district heating system, which can conveniently determine the optimal location of an energy station. In the case study, six oval equipotential RCnetwork lines were described. The maximum RCnetwork reached 137.04% in the E4 location, and the minimum RCnetwork was 89.22% in the E11 location. The results showed that the optimal energy station location was near the district load center and biased to the side with higher building loads. Finally, a new energy utilization mode that coupled a combined cooling, heating and power (CCHP) system and a DVFSP district heating system was proposed. Economic analyses were carried out for the coupled system based on the following electric load (FEL) strategy and the following thermal load (FTL) strategy. The results confirmed that, in terms of the payback period and partial load rate (PLR) of the prime mover, the FEL strategy was more suitable for the coupled system. These results can provide guidance for district heating system design and management.

Research Progress of Energy Utilization of Agricultural Waste in China: Bibliometric Analysis by Citespace

Energy utilization of agricultural waste, due to the depletion of petroleum resources and the continuous deterioration of the ecological environment, has become an increasingly important development area at present, with broad prospects. The Citespace software was used to systematically summarize the research hotspots, development, and frontiers of researches on the energy utilization of agricultural waste in China from 1999 to 2018. The results show that (1) the number of publications in this field has increased, which includes a steady development stage, a rapid development stage, and a fluctuation and decline stage. (2) Research hotspots focused on technology for energy utilization of agricultural waste, benefits analysis of energy utilization of agricultural waste, energy conversion and upgrading path of agricultural waste, and energy potential of agricultural waste. (3) Development of research hotspots go through five stages: “technology for energy utilization of straw and the disposal of livestock and poultry waste”, “exploration of energy utilization mode of agricultural waste and the disposal of by-product from energy utilization of agricultural waste”, “technology upgrading from agricultural waste to fuel ethanol and recycling of livestock and poultry waste”, “resource recycling of by-product from biogas ” and “energy utilization of livestock and slaughterhouse waste”. It has revealed the focus in this field was changing from planting waste to breeding waste, and from unprocessed waste to by-product from energy utilization. (4) Energy utilization of slaughterhouse waste and cow manure has started to be considered as the frontiers of researches.

Respiratory Metabolism and Antioxidant Response in Chinese Mitten Crab Eriocheir sinensis During Air Exposure and Subsequent Reimmersion.

Chinese mitten crab, Eriocheir sinensis, often suffers from severe air exposure stress during transportation and culture; high mortality occurs due to desiccation. In this study, the effects of air exposure stress (0, 2, 4, 8, and 16 h) and reimmersion (2, 6, 12 h) on respiratory metabolism and antioxidant responses in Chinese mitten crabs were studied under laboratory conditions. The results showed that air exposure and reimmersion had a significant impact on the oxygen consumption rate (OCR), ammonia excretion rate (AER), oxygen to nitrogen ratio (O:N), superoxide dismutase (SOD), catalase (CAT), succinate dehydrogenase (SDH), and lactate dehydrogenase (LDH). Significant interaction between air exposure and reimmersion was observed for OCR, AER, O:N, SOD, CAT, SDH, and LDH in Chinese mitten crab. During the air exposure stage, SOD, CAT, and LDH activities in the gills and hepatopancreas first increased and then decreased as air exposure time increased. All of these parameters were significantly higher in the 4-h air exposure group than those in the control group. All the parameters were significantly lower in the 16-h air exposure group than those in the control group, except LDH in the hepatopancreas. However, SDH activity gradually decreased with increased air exposure time, and all the air exposure groups were markedly lower than those in the control group in the gills. During the reimmersion stage, OCR, AER, and O:N restored to normal levels after 12-h reimmersion, except in the 16-h air exposure group, where OCR and O:N were significantly higher than those in the control group and AER was significantly lower than that in the control group. The LDH activity in all groups restored to normal levels after 12-h reimmersion. The SDH, SOD, and CAT activities of the 2- and 4-h air-exposed groups returned to normal levels after 12-h reimmersion; however, these three parameters were still significantly higher in the 16-h air-exposed group than in the control group in the gills and hepatopancreas. Overall, Chinese mitten crabs reduce aerobic respiration and increase anaerobic respiration capacity during desiccation. Under air exposure stress, Chinese mitten crabs change their energy utilization mode to meet their energy demands and adjust their respiratory metabolism and antioxidant enzymes activities to adapt to adverse environments.

Characterization of Renewable Energy Utilization Mode for Air-Environmental Quality Improvement through an Inexact Factorial Optimization Approach

Energy-related environmental problems have been hot spot issues in regional energy system sustainable development. Thus, comprehensive planning of energy systems management is important for social and economic development, as well as environmental sustainability. In addition, uncertainties and complexities, as well as their potential interactions pose a great challenge for effective management in energy and environmental system. This study proposes a stochastic factorial energy systems management model to conduct uncertainties and risks in the energy systems, as well as handle their interaction effects among different environmental policies. The developed method can not only tackle uncertainties expressed as probability distributions and even interval values, but also be applied to determine decision alternatives associated with multiple economic penalties if the formulated environmental policy targets are violated. Meanwhile, by introducing the factorial technology, it can analyze a parameter’s impact on the system and their coordination effect. To verify the feasibility and effectiveness of the proposed method, the developed model was applied to a hypothetical case study for energy structure optimization under considering energy supply, SO2 emissions reduction, and environmental quality requirements. Multiple facilities, related environmental pollutants, and energy demand levels were taken into account. Moreover, the key factors of the system and their interaction effect were discovered. The results indicated that the developed method can resolve meritorious uncertainties in decision-making and analysis, generate effective management programming under multi-levels of the proposed energy and environmental systems. The method can be used for supporting the adjustment for allocating fossil fuels and renewable energy resources, analyzing the tradeoff between conflicting economic and environmental objectives and formulating the local policies.

Investigation on Equivalent Trans-utilization Mode and Benefit of Wind Energy

For economic benefit of wind power generation, the equivalent conversion relationships and models between the different “quality” energy are studied deeply in the conversion processes of wind energy. Considering the effect of load demand characteristics and energy supply price on the wind energy utilization mode comprehensively, the multi-objective trans-utilization optimization model of wind energy is established, which the objections are both the maximum wind energy utilization ratio and comprehensive operational benefit of the energy consumption systems. Then, the quantum-behaved particle swarm optimization method is used to solve the model. By contrast to the traditional unitary energy supply mode, the results showed that the proposed models can improve the wind energy comprehensive utilization rate, and increase energy selling benefit of the energy supply system. The rationality and superiority of models are verified, and that provides a new idea for the large-scale develop and utilize wind energy.

Research on renewable energy power generation complementarity and storage distribution model

This paper mainly studied the equivalent conversion relationships and model of different “quality “energies in process of multi-energy conversion. In energy interconnection system containing wind turbine, photovoltaic cell and energy storage systems, it gives renewable energy and storage distribution development model, considering comprehensive effect of load demand characteristics on energy utilization mode, multi-objective optimization model is established with objectives of both maximized energy utilization ratio and minimized system operation costs. Then, take Chinese one certain area as scenario, and give out “renewable energy utilization“, “energy transfer” and “total operating cost” three different analyses, according to the connection model. The result is compared with that for traditional energy utilization model. Feasibility of the proposed model is verified with simulation results.

A Model for Regional Energy Utilization by Offline Heat Transport System and Distributed Energy Systems—Case Study in a Smart Community, Japan

Under the Kyoto Protocol,Japanwas supposed to reduce six percent of the green house gas (GHG) emission in 2012. However, until the year 2010, the statistics suggested that the GHG emission increased 4.2%. What is more challenge is, afterFukushimacrisis, without the nuclear energy,Japanmay produce about 15 percent more GHG emissions than1990 inthis fiscal year. It still has to struggle to meet the target set by Kyoto Protocol. The demonstration area of “smart community” suggests Japanese exploration for new low carbon strategies. The study proposed a demand side response energy system, a dynamic tree-like hierarchical model for smart community. The model not only conveyed the concept of smart grid, but also built up a smart heat energy supply chain by offline heat transport system. Further, this model promoted a collaborative energy utilization mode between the industrial sector and the civil sector. In addition, the research chose the smart community inKitakyushuas case study and executed the model. The simulation and the analysis of the model not only evaluate the environmental effect of different technologies but also suggest that the smart community inJapanhas the potential but not easy to achieve the target, cut down 50% of the CO2 emission.