Rural Grid Research Articles

Comprehensive evaluation of rural regional integrated clean energy systems considering multi-subject interest coordination with pythagorean fuzzy information

In the development of a comprehensive clean energy system in rural areas, how to evaluate it scientifically and effectively is an urgent problem to be solved. Artificial intelligence has already been widely applied in the field of energy technology, but its application in the comprehensive benefit evaluation is still insufficient. The purpose of this study is to conduct a comprehensive evaluation of the rural, regional integrated clean energy system with coordinated multi-subject interests. Firstly, the interest relationship between the subjects of the participating rural regional comprehensive clean energy system is analyzed. And, the comprehensive benefit evaluation index system is established based on farmers, rural grid, new energy investment operators, government and interest subject reciprocity partners. Secondly, Sugeno-Weber aggregation operators are more flexible and used to acquire smooth aggregated outcomes from a group of information in a single set. Moreover, an algorithm of the multi-attribute decision-making process also reveals the supremacy and reliability of the research work. A case study is established to evaluate the rural integrated clean energy system with coordinated multi-subject interests. The results are as follows. The index system reflects the characteristics of the comprehensive clean energy system in rural areas, such as environmental characteristics, economic characteristics, safety characteristics and clean energy characteristics. The advantages and validity of developed research work are proved by comparing the findings of pioneered approaches with existing mathematical operators. The ranking of suitable energy sources is Solar power > Biomass energy > Geothermal energy > Wind and hydropower based integrated clean energy system.

Studying the Intelligent Power Distribution and Consumption of the Power Grid and its Cost Structure Using Big Data Analysis

Based on the analysis of big data, this paper studies the impact of user behavior response on the cost structure of the microgrid system in the power grid system. The article first conducts in-depth research on distributed power generation and energy storage systems, focusing on the principles and output characteristics of smart power distribution and utilization in power grids, researches smart power distribution and utilization systems in power grids, and makes a more comprehensive discussion of the current situation. Secondly, a big data analysis platform was built, and distributed storage and computing were studied. The platform was used to perform distributed storage and regulation of electricity consumption data, and the electricity consumption information data was divided into the important load, controllable load and transferable load, constructed a microgrid system model based on electricity consumption behavior response, and analyzed a calculation example. After that, a micro-grid system was simulated based on HOMER software, and the optimal capacity configuration of the system was performed. Under this configuration, the micro-grid system has the highest economic efficiency. At the same time, a demand-side load control system was built. Introduced distributed power as a controllable load, integrated new energy access and load control technology, coordinated the contradiction between the power grid and distributed power, and completed a cost-benefit analysis. Finally, for demand-side management electricity price response, peak-valley time-of-use price, the most important implementation method, according to the cost structure theory, the peak-valley period is divided according to the membership function in fuzzy mathematics, and the user's response model to peak-valley time-of-use price is established. The experiment uses the original data to simulate, find the user response model parameters based on the load transfer rate, and complete the comparative analysis of the effect under the peak-valley time-of-use electricity price, which is of great significance to the implementation and improvement of the peak-valley time-of-use electricity price project. The analysis results of the calculation examples show that the method constructed in this paper can effectively realize the power quality analysis of the distribution network in the big data environment. The research results provide technical support for the management of the rural grid voltage deviation of the power company, and lay the foundation for improving the safe operation and management of the power grid.

Modeling load distribution for rural photovoltaic grid areas using image recognition

Expanding photovoltaic (PV) resources in rural-grid areas is an essential means to augment the share of solar energy in the energy landscape, aligning with the “carbon peaking and carbon neutrality” objectives. However, rural power grids often lack digitalization; thus, the load distribution within these areas is not fully known. This hinders the calculation of the available PV capacity and deduction of node voltages. This study proposes a load-distribution modeling approach based on remote-sensing image recognition in pursuit of a scientific framework for developing distributed PV resources in rural grid areas. First, houses in remote-sensing images are accurately recognized using deep-learning techniques based on the YOLOv5 model. The distribution of the houses is then used to estimate the load distribution in the grid area. Next, equally spaced and clustered distribution models are used to adaptively determine the location of the nodes and load power in the distribution lines. Finally, by calculating the connectivity matrix of the nodes, a minimum spanning tree is extracted, the topology of the network is constructed, and the node parameters of the load-distribution model are calculated. The proposed scheme is implemented in a software package and its efficacy is demonstrated by analyzing typical remote-sensing images of rural grid areas. The results underscore the ability of the proposed approach to effectively discern the distribution-line structure and compute the node parameters, thereby offering vital support for determining PV access capability.

Economic sustainability and social inclusion in rural electrical grid design

Electricity access and affordability are critical for sustainable development. A significant global population without access to electricity is in the rural communities of developing countries. Rural grid investments are unattractive to investors due to low electricity demand and poverty of rural consumers. This paper assessed the financial capacity of rural dwellers to pay for electricity installation. The results reveal that rural consumers can barely pay for electricity. We propose a paradigm shift and alternative grid design models that recognize the various economic and social status of rural consumers. One suggested model proposes using agricultural production to drive social inclusion and economic sustainability of microgrid investments.

A Seamless Control of Grid-Connected PV System for Alleviating PV Penetration in Rural Grid Using Supercapacitor Accompanying With DSTATCOM and Improved CTF Control

A Seamless Control of Grid-Connected PV System for Alleviating PV Penetration in Rural Grid Using Supercapacitor Accompanying With DSTATCOM and Improved CTF Control

Low voltage grid resilience: Evaluating electric vehicle charging strategies in the context of the grid development plan Germany

The ongoing transition to decentralized renewable energy sources and sector-coupled consumers is reshaping the energy system. Changes at lower grid levels can stress lines and transformers. Crucial for a successful local energy transition are grid relief measures. Battery electric vehicles contribute to higher loads on grid equipment but also offer flexibility. This paper assesses the influence of four different charging strategies for battery electric vehicles across five representative low-voltage grids based on the grid development plan in Germany for the years 2021, 2037, and 2045. Results indicate that grid stress, specifically capacity stress, will emerge by 2037 and 2045. Decentralized photovoltaic systems are the primary contributors to this stress due to high simultaneous generation. Up to nearly 20% of photovoltaic power may need to be curtailed in 2045, especially in rural grids during the summer, to prevent overloads.Charging strategies linked to wholesale power market prices can inadvertently lead to higher consumption-induced grid overloads, necessitating the consideration of local grid restrictions. Implementing grid-friendly charging strategies, such as reduced charging power or alignment with local photovoltaic production, can mitigate those grid overloads from almost 8% down to 0.11%. However, these charging strategies have limited impact on photovoltaic-induced overloads due to the low number of connected battery electric vehicles during the day.In summary, appropriate charging strategies can ease low-voltage grid stress and are suitable measures to manage the challenges of decentralized energy transition and battery-electric vehicle adoption.

Impact of the integration of photovoltaic installations in rural grids: case study

This work studies the impact of the photovoltaic installation in a rural village of the Pyrenean region of Spain. Based on real data of electricity consumption a PV generation system has been designed and its effect in the distribution power losses and the voltage profile are analysed. As a second step, a storage system has been added to the PV system and the optimal dimension of the hybrid system has been calculated in order to reduce the peak value of the demanded power.

Voltage Regulation through Wide Area Voltage Control of HV/MV Transformers and Inverters’ Reactive Power Support

This paper presents a technical evaluation of two different methods to avoid the excessive voltage deviations caused by dispersed generation in distribution grids. Two voltage regulation methods, wide area voltage control of HV/MV transformer and inverters’ reactive power support, are simulated in several real rural grids with different topologies located in Northern Germany. In all these analysed grids the high penetration of dispersed generation produces big power flow reversals during low load periods. The objective of implementing both voltage regulation methods is to reduce voltage deviations in such an extent that voltage band violations no longer act as the principal obstacle to host more dispersed generation in the distribution grid. We evaluate the effectiveness of these two methods through a power system analysis program and analyse the reciprocal effects caused by simultaneous use of both methods. Moreover, the concept of “voltage inhomogeneity” is introduced.

АНАЛИЗ КОНФИГУРАЦИИ СЕЛЬСКИХ ЭЛЕКТРИЧЕСКИХ СЕТЕЙ 10 КВ

Currently, the works of domestic and foreign scientists explore options for improving medium-voltage electrical grids by introducing distributed automation tools. However, statistical data on the configuration of existing rural power grids of 10 kilovolts are not sufficiently presented in the literature. (Research Purpose) The research purpose is analyzing the configuration of rural electrical grids of 10 kilovolts, taking into account the transformer substations connected to them and the types of wires used. (Materials and methods) The analysis of 165 supporting schemes of 10 kilovolt overhead power transmission lines of one of the electric grid companies was carried out. (Results and discussion) It is found out that the arithmetic mean of the length of the overhead line of 10 kilovolts to the most remote point of the grid is 9.2 kilometers, and the total length is 13.2 kilometers. It is found that that the specific power per kilometer of the rural grid of 10 kilovolts is 82 kilovolt amperes per kilometer. At the same time, an average of 5 taps are from one 10-kilovolt line, and the average length of the them is 0.68 kilometers. It was also revealed that 72 percent of the total length of the analyzed power transmission lines of 10 kilovolts does not meet the requirements for mechanical strength under icy and wind loads. (Conclusions) The analysis reflects the current configuration of rural 10 kV power grids in the Orel region, while 10 kV overhead lines in other regions may have their own characteristics.

Optimization-based framework for low-voltage grid reinforcement assessment under various levels of flexibility and coordination

The rapid electrification of residential heating and mobility sectors is expected to drive the existing distribution grid assets beyond their planned operating conditions This change will also reveal new potentials through sector coupling, flexibilities, and the local exchange of decentralized generation. This paper thus presents an optimization framework for multi-modal energy systems at the low voltage (LV) distribution grid level. In this, we focus on the reinforcement requirements of the grid and the techno-economic assessment of flexibility components and coordination between agents. By employing a multi-level approach, computational complexity is reduced, and various levels of coordination and flexibilities are implemented. We conclude the work with a case study for a representative rural grid in Germany, in which we observe high economic potential in the flexible operation of buildings, majorly thanks to better integration of photovoltaics. Across all paradigms barring a best-case benchmark, grid reinforcement based on a mix of passive and active measures was necessary. A synergy effect is observed between flexibilities and coordination, as their combination reduces the peaks to the extent of completely avoiding grid reinforcement. The presented framework can be applied with a wide range of grid and component types to outline the broad landscape of future LV distribution grids.

Power Quality Improvement in Rural Grid Using Adaptive Control Algorithm to Enhance Wind Energy Penetration Levels

The intermittency associated with Wind Energy causes Power Quality (PQ) disturbances, which in turn can limit the penetration levels. These penetration levels are further restricted due to the non-linear (NL) loads and the weakness of the grid (especially in the rural grid). This paper proposes a methodology to enhance wind power penetration levels into the rural grid by mitigating PQ disturbances using a DSTATCOM controlled by Adaptive Least Mean Fourth (ALMF) control. The proposed algorithm computes the active and reactive load current components with the help of updated weights by continuously adapting the changes in grid voltages, wind speed and DC-link voltage to generate reference currents, which are used to generate switching signals for the DSTATCOM. Various case studies establish the effectiveness of the proposed algorithm in MATLAB simulation and experimentally to enhance the wind energy penetration level up to 25% into the rural grid with a short circuit ratio as low as 2.74 in the presence of NL loads.

Assessment method of large-scale distributed power consumption capacity for rural grids

As the scale of photovoltaic (PV) access continues to expand, both transmission and distribution grids are experiencing systemic consumption problems, with rural distribution grids being particularly prominent. An accurate assessment of distributed power consumption capacity is crucial to the improvement of distributed power consumption capacity. Firstly, taking into account the uncertainty of the output of the distributed power supply and comprehensive consideration of power quality, reliability of the electricity supply and operational influences, A comprehensive index evaluation system has been established to assess the ability of distributed power sources to consume; secondly, hierarchical analysis and improved gray correlation analysis are used to assign weights to the indexes; finally, a Monte Carlo model is used to identify the consumption capacity of rural power grids. This method can provide a comprehensive and accurate assessment of the consumption capacity of large-scale distributed power sources in new rural power grids, and also provide data support for solving the problem of new energy consumption in power grids.

A brief discussion on the problems and suggestions of post-supply management in China

With the rapid development of China's social economy, the problem of post-supply management of public goods has become increasingly prominent. This paper takes the rural power supply system as an example to make an in-depth study of post-supply management. In recent years, the rapid development of rural areas has put forward higher requirements for the supply and management of rural power grid. Therefore, we must pay more attention to rural power grid transformation, and timely respond to farmers' demand for rural power grid to meet the needs of rural development in the new era. This paper firstly clarifies the concept of post-supply management, then analyzes the formation background and performance of this problem in practice, and finally analyzes the problems existing in the process of rural grid transformation in detail, and puts forward the framework of the feasibility scheme.

Rural EV charging: The effects of charging behaviour and electricity tariffs

As with many socio-techno transitions, rural areas often get left behind and Electric Vehicles (EVs) are no exception. This paper aims to highlight the lack of academic discourse surrounding the transition to EVs for rural areas as well as presenting the modelling and results of several potential scenarios for rural EV charging habits. Utilising 7-day travel patterns for a small rural village in the Peak District National Park, UK, this paper investigates the energy requirements and potential recharging patterns should this settlement switch all vehicles to EVs. Two key parameters have been incorporated into the EV charging model; electricity tariffs and charging behaviour based on current battery State of Charge (SoC). The model simulated a 4 week period, from which a time period, with a minimum length of one week, where energy balance could be assured for the whole system was extracted. Results show that instantaneous energy and power requirements can vary drastically depending on electricity tariffs and charging behaviours which could be a major cause for concern for rural grid infrastructure, and for the larger EV transition across the UK.

Rural electrification subsidy estimation: a spatial model development and case study

A global push to achieve universal electricity access, paired with drastic reductions in the cost of decentralized electricity technologies, has led to significant research on how best to roll out access to rural communities in sub-Saharan Africa. Various geospatial electrification models have been developed to aid the decision-making process considering decentralized grid alternatives such as mini-grids and solar home systems. Despite these tools suggesting that in many cases, decentralized systems are a more cost-effective electricity access pathway, grid extension still predominates in practice. This is due, at least in part, to institutional structures in most countries that provide significant direct and indirect subsidies to grid extension projects, commonly through publicly-owned utilities. These sources of finance are generally not available to primarily privately operated off-grid energy service providers. However, the subsidy provided for grid extension projects is not well understood. In this paper, we employ utility grid extension costs and revenue data, and geospatial grid infrastructure data to estimate the size and distribution of subsidy implicitly provided to rural grid extension projects for 129 communities in Mombasa County, Kenya. We also estimate subsidies for hypothetical off-grid electricity systems in the same communities that would deliver equivalent services to the grid. We allocate the cost of shared medium voltage (MV) distribution infrastructure using a marginal and an average cost method for grid extension and compare these with subsidies for off-grid systems. We find that the average of average subsidy per customer across communities for grid extension is US$5,118 and US$5,330 for the two MV cost allocation methods respectively, while for the off-grid systems the corresponding average of average subsidies are US$3,380, using a real discount rate of 1.3% evaluated from a nominal discount rate of 8% and inflation rate of 6.7%. Our results show that in the communities in our case study, 40% and 37% of the communities would command less subsidy while served by minigrids over the grid, and the switch would save 50% and 54% of the total cost for average and marginal cost allocation methods respectively. We also show that by using a multi-model approach to electrification and by reallocation of implicit subsidies that have been exclusive to grid extension to other technology options utilities can cast the net wider, without an increase in budgets.

A Distributed Power Consumption Metering Assessment Method for the Energy Internet

This paper proposes a distributed power supply consumption metering assessment index system and method for rural energy internet, which can be used in the dispatch and design departments of power companies. The method can solve the problems that exist in the existing distribution system, such as the lack of basis for siting and capacity determination and access of large-scale distributed power units, and the single and one-sided assessment index of distributed power consumption capacity. Firstly, analysing the characteristics of the new rural power grid, considering the impact of the uncertainty of distributed power supply output, organically combine the influencing factors of power quality, power supply reliability and operational safety and establish a multi-dimensional index evaluation system to measure the ability of distributed power sources to consume. Finally, the improved fuzzy estimation is used to determine the consumption capacity of the rural grid. The data of a rural grid operation is analysed by case study to accurately assess the consumption capacity of distributed power sources in the area.

Study on optimization method of rural integrated energy system including renewable energy

Due to the implementation of the rural revitalization strategy, the urbanization process in rural areas has been accelerated in China, as the economy has grown more rapidly and energy consumption has increased. Rural power infrastructure, however, remains inadequate and the rural power grid is relatively weak, which further exacerbates the contradiction between rural energy supply and demand. To solve these problems and achieve sustainable development, renewable energy sources should be utilized for energy supply in rural areas to reduce the demand for power from rural grids. Using this idea, this paper proposes an optimization method for an integrated energy system for rural areas that includes renewable energy sources. Firstly, a model of the output of equipment such as wind and solar biogas, as well as the model of energy storage equipment, is constructed. A portion of flexible load is considered when estimating energy consumption on the demand side. A day-ahead optimization model for rural energy systems is designed to minimize costs, which allows different energy sources to play complementary roles under the constraints of power balance, output limits, etc. The approach proposed in this paper may provide a comprehensive solution for optimizing the operation of an integrated rural energy system by improving its energy efficiency and maximizing its use of renewable energy resources. Furthermore, the article also provides specific examples of the feasibility of the method.

Integrated design of photovoltaic power generation plant with pumped hydro storage system and irrigation facility at the Uhuelem-Amoncha African community

— Seasonal and location dependence of renewable energy resources have limited their applications in power generation. Energy storage systems are promising solutions to the intermittence of renewable energy resources. Rural electricity grids are faced with economic sustainability challenges due to low power demand and poverty. A rural grid design around economic drivers like agriculture and micro industries can mitigate poverty and improve economic sustainability of rural grids. This paper presents an integrated design for photovoltaic power generation with a pumped hydro storage system for irrigation and community utilization. The design explored the natural availability of water body in an elevated settlement area that offers a natural storage height for hydro energy storage. A photovoltaic generation plant was designed to power a pump as a turbine system for water storage and generation. HOMER® energy simulation software was deployed in the simulation. The result shows a satisfactory net present cost for the possible integration of a pumped hydro storage system in a photovoltaic generation plant as the most viable option to provide power at a power supply probability of 99.9% and water for irrigation. The benefits from the irrigation and water supply will enhance the community's socio-economic development and sustain the investment.

Optimal sizing of hybrid Systems for Power loss Reduction and Voltage improvement using PSO algorithm: Case study of Guissia Rural Grid

This work proposes a method for sizing and reducing power losses (MSRPL) of a hybrid photovoltaic and wind system (HPWS) in a radial distribution network (RDN) by developing an objective function, thanks to particles swarm optimization (PSO). The constraints defined on the objective function has permitted us to size the photovoltaic generator, wind turbine and total production cost. The proposed system configuration (PSC) improved the voltage level and minimized the power losses (PL) in the radial network. The proposed PSO algorithm was tested on Guissia (10°30’N, 15°18’E) rural electric grid (GREG) in the far north of Cameroon, which has a radial configuration. The integration of a battery bank allowed the system to have the power factor correction and production of active and reactive power. The test on IEEE 33-bus and IEEE 69 bus showed the robustness of the system and the reliability of the proposed method which also minimized the total cost of the system over 20 years.

Flower Greenhouse Energy Management to Offer Local Flexibility Markets

Electricity access is strongly linked to human growth. Despite this, a portion of the world’s population remains without access to energy. In Colombia, rural communities have energy challenges due to the National Interconnected System’s (NIS) lack of quality and stability. It is common to find that energy services in such locations are twice as costly as in cities and are only accessible for a few hours every day due to grid overload. Implementing market mechanisms that enable handling imbalances through the flexible load management of main loads within the grid is vital for improving the rural power grid’s quality. In this research, the energy from the rural grid is primarily employed to power a heating, ventilation, and air-conditioning (HVAC) system that chills flowers for future commerce. This load has significant consumption within the rural grid, so handling HVAC consumption in a suitable form can support the grid to avoid imbalances and improve the end-user access to energy. The primary responsibilities of the flower greenhouse operator are to reduce energy costs, maximize flexibility, and maintain a proper indoor temperature. Accordingly, this research proposes a flexible energy market based on the bi-level mixed-integer linear programming problem (Bi-MILP), involving the Agricultural Demand Response Aggregator (ADRA) and the flower greenhouse. ADRA is responsible for assuring the grid’s stability and quality and developing pricing plans that promote flexibility. A flower greenhouse in Colombia’s Boyacá department is used as an application for this research. This study looked at the HVAC’s flexibility under three different pricing schemes (fixed, time-of-use, and hourly) and graded the flower greenhouse’s flexibility as a reliable system.