Economic Operation Model Research Articles

Collaborative Optimization Scheduling of Source-Network-Load-Storage System Based on Ladder-Type Green Certificate–Carbon Joint Trading Mechanism and Integrated Demand Response

To fully leverage the potential flexibility resources of a source-network-load-storage (SNLS) system and achieve the green transformation of multi-source systems, this paper proposes an economic and low-carbon operation strategy for an SNLS system, considering the joint operation of ladder-type green certificate trading (GCT)–carbon emission trading (CET), and integrated demand response (IDR). Firstly, focusing on the load side of electricity–heat–cooling–gas multi-source coupling, this paper comprehensively considers three types of flexible loads: transferable, replaceable, and reducible. An IDR model is established to tap into the load-side scheduling potential. Secondly, improvements are made to the market mechanisms: as a result of the division into tiered intervals and introduction of reward–penalty coefficients, the traditional GCT mechanism was improved to a more constraining and flexible ladder-type GCT mechanism. Moreover, the carbon offset mechanism behind green certificates serves as a bridge, leading to a GCT-CET joint operation mechanism. Finally, an economic low-carbon operation model is formulated with the objective of minimizing the comprehensive cost consisting of GCT cost, CET cost, energy procurement cost, IDR cost, and system operation cost. Simulation results indicate that by effectively integrating market mechanisms and IDR, the system can enhance its capacity for renewable energy penetration, reduce carbon emissions, and achieve green and sustainable development.

Low-carbon economic operation of energy hub integrated with linearization model and nodal energy-carbon price

Energy hub has positive significance in absorbing renewable energy, improving energy utilization efficiency and reducing carbon emissions. Considering both linearization energy hub model and nodal integrated energy-carbon price, a low-carbon economic operation model of energy hub is constructed by taking advantage of the bi-level optimization structure. First, in order to simplify the modeling procedures and improve the solving efficiency, reversibility judgment criteria and linearization processes in energy hub modeling are improved. Then, a nodal integrated energy-carbon pricing strategy is proposed and calculated according to flow tracing method and carbon emission flow method. Additionally, the bi-level optimization model and solution procedure are presented to obtain the optimal operating states of energy hubs. At last, for the simulation results, the characteristics and the influence of nodal price on energy consumption behaviors of energy hubs are analyzed, the proposed model is effective to reduce the carbon emissions and operating costs.

Smallholders in Capitalist Agriculture: Persistence and Challenges

Abstract This paper posits that the majority of “smallholders” in contemporary China are commodity producers who must engage in various commodity exchanges to carry out agricultural production and accomplish their social reproduction. Consequently, “smallholder” refers to a family-based economic operation model, rather than a social identity or psychological identification. Within this framework, the study focuses on the intricate relationships between smallholders, various commodity markets, and other market participants. Specifically, it examines two aspects: the relationship between smallholders and capitalized large-scale producers and other agriculture-related capital entities, and the relationship between smallholders and the commodified labor force. The paper argues that the interaction between smallholders and capitalized large-scale producers is not a zero-sum game of mutual replacement; except in certain areas, smallholders are not driven out of agricultural production by large-scale capitalized producers, but coexist and interact with them in various ways. On the other hand, smallholders heavily rely on short-term hired labor for their agricultural production, and many also become wage earners themselves, participating in the agricultural production of other producers and earning wage income. Compared to the expansion of capitalized large-scale production, the most significant challenge facing China’s smallholder economy, as this paper contends, is the intergenerational reproduction crisis brought about by the aging of the labor force and the urbanization of the younger generation.

BAS-PSO Algorithm for Integrated Energy System Optimization of Multiple Energy Supply Facilities

Regional low carbon will play an important role in the path of achieving the “double carbon” goal, and there are still many key technologies to be broken in its planning research. In this paper, an optimal scheduling model of integrated energy system with multiple energy supply devices is established by using Beetle Antennae Search-Particle Swarm Optimization (BAS-PSO) algorithm. First, in the scheduling model, a carbon trading mechanism is introduced and a stepped carbon trading cost model is constructed to constrain the carbon emissions of the plant. Then, using drosophila algorithm, the premise of whether wind power generation and photovoltaic power generation need to be built is determined by judging the economics of wind power generation and photovoltaic power generation in the construction area, and then the target power consumption curve and new energy power supply output curve are fitted. Then use the life cycle analysis method to analyze the carbon emissions generated by electric energy storage equipment, consider the carbon trading mechanism in the system economic operation model, and solve the model by BAS-PSO algorithm to overcome the problems of local optimum and slow convergence speed. Finally, a typical park integrated energy system is simulated to analyze the economic operation conditions and energy efficiency level of the system before and after participation in demand response. The innovation of this paper lies in considering the carbon trading mechanism and solving with the optimized BAS-PSO algorithm. Considering carbon trading can effectively improve the system wind power consumption capacity, and the optimized BAS-PSO algorithm improves the defects of traditional PSO. The simulation analysis results show that the established optimal scheduling model with multiple energy supply devices can realize the optimal operation of the integrated energy system of the park in the demand response environment; the improved BAS-PSO finds the lowest energy consumption within 100 iterations in 21 out of 50 iterations; the improved BAS-PSO algorithm reduces the energy consumption by 27.1 kW on average.

Part-load operation risk assessment of hydropower units in hydro–wind–solar​ hybrid system considering hydraulic characteristics

Establishing hydro–wind–solar hybrid system (HWSHS) is essential to combat the fluctuant and uncertain variable renewable energy (VRE). In HWSHS, the main function of hydropower is gradually changing from electricity generation to equal emphasis on electricity generation and regulation. This means that hydro units are sometimes forced to operate in part-load regions to regulate and avoid power shortage. However, hydropower units operating in the part-load regions exist potential safety risks owing to the hydraulic characteristics (e.g., vibration and pressure fluctuation et al.). Here, an economic operation model of HWSHS considering precise head loss and shared pipeline is proposed. Then, a risk assessment framework of hydro units in HWSHS operating in the part-load regions is presented. Meanwhile, the uncertainty of VRE is also considered. Finally, the model and framework are applied to a case in the Jinsha River basin of China. The results show that (1) the risk framework could be assessed the safety risk of hydropower units for different scenarios during a period and even be applied to future risk forecasts. For example, the risk of hydropower units on May 3, 2019 is lower than the other two days; (2) the risk of hydropower units from May 1, 2019 to May 3, 2019 averagely increases to 3.693 h (duration), 15.389% (probability) and 63.721 MW (mileage) compared with the scenario without VRE; and (3) the main factors of hydropower units being forced to operate in part-load regions are the high proportion and the uncertainty of VRE. Thus, the study supplies support for assessing the risk of hydropower units in HWSHS to regulate VRE.

Optimal operation strategies of pumped storage hydropower plant considering the integrated AC grids and new energy utilization

The large-scale development and utilization of new energy resource extremely promotes the construction and application of the flexible DC power grid especially in China. This paper focuses on the operation stability and new energy transmission of an actual regional power grid in North China, including new energy plants, the flexible DC power grid, a pumped storage hydropower plant (PSHP) with variable speed pumped storage unit (VSPSU) and regional AC power grids. According to the operation rules and goals, the economic operation model of the flexible DC-PSHP system is established by the mixed-integer second-order cone programming. Considering the transmission and consumption of the new energy generation, two operation strategies and three simulation scenarios are proposed. The day-ahead optimal operation schemes of PSHP in different scenarios are given by the case simulation. The results show that the proposed strategies can satisfy the operation demands of the regional power grid both in new energy generation transmission and operation economic benefits.

Multi-microgrid low-carbon economy operation strategy considering both source and load uncertainty: A Nash bargaining approach

In order to realize the effective use of energy and promote the full consumption of renewable energy, the microgrid integrated by distributed resources has the potential of resource sharing as independent stakeholders. While, the traditional multi-microgrid interconnection ignores the information privacy of each microgrid, moreover, the cooperation strategy often cannot achieve a fair and reasonable distribution of benefits. Based on this, this paper firstly establishes a microgrid model for the coordination of three energy forms of electricity, heat, and gas. Secondly, considering the actual situation involving uncertainties on both sides of the source and load, robust interval optimization is used to achieve better robustness. Then, combined with the increasingly important low-carbon operation goal, a combined heat and power (CHP) model integrating power to gas (P2G) and carbon capture systems (CCS) is constructed, and the goal of emission reduction is achieved through the carbon trading operation mechanism. Finally, based on the Nash bargaining theory, a multi-microgrid Peer-to-Peer(P2P) low-carbon economic operation model is established, and the alternating direction method of multipliers (ADMM) with good convergence and privacy is used to decomposed the original problem into two sub-problems to solve.

Analysis of Optimal Operation of Charging Stations Based on Dynamic Target Tracking of Electric Vehicles

In view of the large impact of traditional charging stations on the power grid and the investment in the construction of charging stations for electric vehicle infrastructure services, this paper considers the configuration of optical storage equipment in charging stations from a practical point of view and proposes an economic operation strategy for charging stations to meet the economically optimal requirements of different scenarios. First, we analyze the behavioral characteristics of multiple types of electric vehicles, consider the influence of charging queues, and establish a daily load model of charging stations by taking into account the daily monitoring load and nighttime lighting load of charging stations. Then, considering the electric vehicle (EV) charging demand, photovoltaic (PV) output and energy storage charging and discharging power, the daily economic optimal operation problem based on the dynamic target tracking of charging stations is established; the objective is to maximize the daily operating revenue of charging stations under the condition of satisfying the EV charging demand and PV consumption. Secondly, the objective function is linearized, and the economic operation model is transformed into a mixed integer linear programming model for solving, and the simulation is verified under different scenarios. The results show that the economic optimal operation strategy can adapt to the economic operation requirements of charging stations in different scenarios and maximize the charging station revenue.

Bi-level optimal low-carbon economic operation of regional integrated energy system in electricity and natural gas markets

In response to increasing environmental deterioration, the vigorous development of the integrated energy system is an important measure to achieve the goal of carbon neutrality. In order to ensure that the system takes into account the economic operation under the premise of low carbon and environmental protection, this paper proposes a bi-level optimal low-carbon economic operation model for the regional integrated energy system (RIES). At the upper level, the objective of the RIES is economic optimization, which contains the carbon emission cost so that the system would change its preference for high-carbon energy to limit the carbon emission of the system. At the lower level, an electricity and natural gas pricing model is established, and a carbon emission flow (CEF) model is used to calculate the price of carbon emissions. This proposed bi-level optimization model is converted to a single-level mathematical problem with KKT (Karush–Kuhn–Tucker) conditions for efficient calculation. The proposed optimal model is tested on the five-bus power system and seven-node natural gas system, and numerical results indicate the optimal operating model with this proposed carbon pricing method can effectively reduce carbon emissions and minimize the total operating cost of RIES.

Multi-objective optimal capacity allocation of integrated energy system with co-evolution mechanism

Abstract With the deepening of multi-energy flow coupling and the diversification of energy utilization demand, integrated energy system (IES) puts forward higher requirements for the economy and reliability of capacity allocation scheme. However, there is a complex relationship between economy and reliability, which makes it difficult for them to achieve coordinated optimization. Therefore, an economic and reliability optimal capacity allocation method of IES based on improved co-evolution algorithm is proposed. Firstly, the timing scenario reduction method of “wind power-electrical load” based on ordered clustering algorithm and K-means clustering algorithm is proposed. Aiming at minimizing the expected annual cost of construction investment, operation and maintenance, carbon emission and energy purchase cost, and constrained by equipment operation and energy flow balance, a multi-scenario economic operation model is constructed. Considering the dissatisfaction degree of comprehensive energy consumption, the energy supply reliability evaluation model based on Markov chain Monte Carlo (MCMC) method is established. On this basis, the IES multi-objective optimal capacity allocation model is established. Further, based on the orthogonal test method, the influence factors of decision variables on IES economy and reliability are calculated, and the evolution subpopulation of economy and reliability is established, and then the optimization model’s solution method based on improved co-evolution algorithm is proposed. Finally, an example simulation analysis is carried out combined with the actual data of a certain region. The simulation results show that the proposed model can cooperatively improve the economy and reliability of IES capacity allocation scheme, and provide a reference for the optimal capacity allocation of equipment in IES.

Optimized Operation of Integrated Energy Microgrid with Energy Storage Based on Short-Term Load Forecasting

This research proposes an optimization technique for an integrated energy system that includes an accurate prediction model and various energy storage forms to increase load forecast accuracy and coordinated control of various energies in the current integrated energy system. An artificial neural network is utilized to create an accurate short-term load forecasting model to effectively predict user demand. The 0–1 mixed integer linear programming approach is used to analyze the optimal control strategy for multiple energy systems with storage, cold energy, heat energy, and electricity to solve the problem of optimal coordination. Simultaneously, a precise load forecasting method and an optimal scheduling strategy for multienergy systems are proposed. The equipment scheduling plan of the integrated energy system of gas, heat, cold, and electricity is proposed after researching the operation characteristics and energy use process of the equipment in the combined power supply system. A system economic operation model is created with profit maximization in mind, while also taking into account energy coordination between energy and the power grid. The rationality of the algorithm and model is verified by analyzing the real data of a distributed energy station in Wuhan for two years.

Hierarchical optimal energy management strategy of hybrid energy storage considering uncertainty for a 100% clean energy town

In a 100% clean energy town, to meet the energy balance and reduce the impact of power fluctuations on the main grid, in this paper, a hierarchical optimal energy management strategy (EMS) for a hybrid energy storage system (HESS) is proposed. The EMS consists of three layers. To meet the requirement of 100% clean energy, in the upper layer, a HESS economic operation model based on the mixed integer non-linear programming (MINLP) is presented. Then, considering the uncertainty of renewable energy and load, a power prediction model is presented in the middle layer. In addition, to reduce the power disturbance on the main grid caused by the stochastic power, a stochastic model predictive control (SMPC) strategy is implemented to optimize the power allocation of a HESS. In the lower layer, to reduce the power fluctuations of the lithium-ion battery (LiB) when mitigating minute-scale power fluctuations, a HESS optimal power allocation strategy based on Pontryagin's minimum principle (PMP) is proposed. In every control period, each layer is optimized based on the results of the previous layer. Finally, a simulation study is provided to validate the effectiveness of the proposed EMS. The results show that the proposed strategy has good performance in typical scenarios.

Research on Cluster Economy Operation Model Considering Customer Satisfaction

A Real-time electricity market transaction is an important method that is used to realize the interactive balance of source-network-load in a new generation power system. Based on the multi-camp economic choice and the needs of national conditions, the emergence of cluster operators is inevitable. Due to stability and development of photovoltaic users, it is important to evaluate the importance of users in a photovoltaic user group. In the existing model, users are too sensitive to the electricity price, which will lead to too high electricity adjustment rate. In order to make up for the lack of importance ranking research and the high adjustment rate of electricity consumption, this paper will introduce the electric power consumption satisfaction function and propose an optimal pricing model that is based on the master-slave game. The study analyzes the nature of operators’ revenue, and presents a method to calculate the contribution value using the cooperative game theory. The TOPSIS method is proposed to evaluate the ranking of the producers and sellers in the group. The developed illustration verifies the superiority of the cluster economic operation model.

Introduction and Efficiency Evaluation of Multi-storage Regional Integrated Energy System Considering Optimal Operation Integrated Demand Side Response

With the depletion of traditional energy sources, the Regional Integrated Energy System (RIES) came into being to solve the energy crisis and the problem of consumption. The battery, the thermal storage electric boiler and the P2G equipment are added into energy system. The impact of system operation was analyzed after adding different equipment. Then, the demand side response of the electric heating and gas are considered, and the economic operation model of the regional integrated energy system is established with the minimum operating cost of the system as the objective function. Seven scenarios were set up for comparative analysis. The results show that the demand side response of electric, heating, and gas are considered in the regional comprehensive energy system with multiple energy storage devices, which not only makes the load achieve the purpose of peak load cutting and valley filling, but also reduces the phenomenon of abandoned wind and sunlight and the system operation cost.

Research on Key Technologies of Connecting Various Distributed Power Sources to Smart Grid

In order to solve the impact of distributed power supply (DG) access on the fault location and voltage quality of distribution network, the paper combines the characteristics of random fluctuating DG grid connection, and studies a way to use SVG dynamic reactive power compensation to maintain randomness The control strategy of the voltage stability of the fluctuating distributed power supply node, based on the detailed analysis of the determination method of the SVG capacity, a new optimization strategy for the distribution system containing different types of DG is proposed, that is, using the static reactive power generator VG and output-adjustable DG’s own reactive power capacity for fine-tuning control, the use of traditional static compensation device comprehensive adjustment optimization strategy. At the same time, the economic optimization operation model of the distributed energy system is analysed to verify the feasibility of the optimization strategy.

Scheduling Strategy of PV-Storage-Integrated EV Charging Stations considering Photovoltaic Output and User Demand Uncertainty

The PV-Storage-Integrated EV charging station is a typical integration method to enhance the on-site consumption of new energy. This paper studies the optimization of the operation of PV-Storage-Integrated charging stations. Firstly, considering the uncertainty of photovoltaic output and user’s charging demand, a photovoltaic output model and a user charging behavior model were constructed. Secondly, the optimal economic operation model of the PV-Storage-Integrated EV charging stations is proposed based on the cost of purchasing power from the distribution network and the life loss cost model of the battery cycle. The constraints such as the charging and discharging power of the battery and the SOC range of the energy storage battery are considered. Finally, optimal scheduling schemes in different typical scenarios are analyzed, and the results show the effectiveness of the proposed optimal scheduling scheme.

Optimized operation of micro grid electric heating integrated system based on PMV

The characteristics of wind power, such as peak inversion, lead to serious wind abandonment in heating season. With the implementation and use of the heat storage electric boiler (HSEB), the utilization rate of wind power can be effectively improved by establishing the electric heat combined operation system with the HSEB. When the thermal comfort of human body is considered, the heat load will be changed into elastic range, and the regulation range of heating unit will be increased. Based on the analysis of the heat transfer state of the house on the user’s side, the relationship model between the outdoor temperature and the indoor heat supply is established in this paper. On this basis, the micro grid electric heating comprehensive system with the HSEB is constructed. Taking the minimum operation cost of the system as the objective function, the economic optimal operation model of the micro grid electric heating system based on PMV is established. The feasibility of the four schemes is verified by an example. The results show that the micro grid electric heating system based on the PMV contained HSEB can accommodate the abandoned wind power, reduce the fuel cost and reduce the environmental pollution on the premise of ensuring the indoor comfort, which has a good application prospect.

Economic dispatching strategy of distributed energy storage for deferring substation expansion in the distribution network with distributed generation and electric vehicle

Aiming at the problem that the traditional substation expansion method leads to low availability of transformers and distributed generations (DG), and considering the improvement of energy storage operation revenue to reduce the energy storage investment cost, an energy storage economic dispatch strategy for deferring substation expansion is proposed. The strategy takes the charge-discharge balance as the criterion, considers the system security constraints and energy storage operation constraints, and aims at maximizing the comprehensive income of system loss and arbitrage from energy storage operation, and establishes the economic operation model of energy storage, the energy storage power is calculated according to different peak-cutting values, and the operating income of corresponding energy storage power is calculated by substituting it into the economic operation model. Finally, the energy storage power corresponding to the optimal income is determined. Through the simulation and analysis of the IEEE33 bus distribution system, based on the proposed evaluation index, the results show that the economic dispatching strategy proposed in this paper can greatly increase the operating income of energy storage, reduce the equivalent annual investment cost of energy storage equipment by $54,930 compared with the substation expansion scheme, and increase the annual availability rate of transformers to 32.8%, the annual availability hours of distributed generations increased by 267 h.

Exploring Economic Criteria for Energy Storage System Sizing

This paper presents two economic criteria for guiding the energy storage system (ESS) sizing in grid-connected microgrids. The internal power output model and the economic operation model of ESS are firstly established. Then, the combination of heuristic adjustment strategy and hybrid particle swarm optimization algorithm are introduced to solve the optimal operation model of ESS. Then according to the ESS life model and cost-benefit analysis, a static investment economic criterion which is easy and simple to be calculated is proposed to demonstrate the economic feasibility of ESS investment programs in the short term. Considering the time value of currency, a dynamic investment economic criterion is proposed later for long-term investment projects. Furthermore, the ESS sizing boundary of achieving profits could be also obtained according to the criteria which can indicate the economic attractiveness or resistance to ESS investors in the microgrid. A case study has verified its effectiveness. At the same time, sensitivity analysis is given to show the impact on key parameters, such as investment unit price and electricity purchase price on ESS investment.

Economic Operation Modeling and Optimization of an Island Micro Grid Considering Load Control

This paper proposes an optimization control of micro-grid system economy operation model. It coordinates the new energy and storage operation with diesel generator output, so as to achieve the economic operation purpose of micro-grid. In this paper, the micro-grid network economic operation model is transformed into mixed integer programming problem, which is solved by the mature commercial software, and the new model is proved to be economical, and the load control strategy can reduce the charge and discharge times of energy storage devices, and extend the service life of the energy storage device to a certain extent.