Equipment Capacity Research Articles

Research and application of energy supply and demand allocation method for rural differentiation

China is a vast country with complex and diverse energy, economy, society, culture and natural geography. Due to the great differences in geographical location, degree of development and resource endowment, the rural energy consumption scene is complex and changeable, and the energy structure configuration has problems such as single scene, poor flexibility and applicability. Therefore, this paper first puts forward the development scenario of rural energy differentiation; Then, based on the classification of rural energy development differentiation scenarios, a multi-objective planning weight allocation model is established for the three goals of economy, environmental protection and energy conservation when the system is running; Finally, in order to verify the superiority of this model, three typical rural areas are selected for verification, and the flexible and adaptive rural comprehensive energy optimal allocation results of the travel alienation scenario are obtained respectively. The simulation results show that the optimal allocation method can achieve the purpose of adapting different target weights through scene differences to configure the equipment capacity of rural integrated energy system, so as to meet the purpose of rural energy supply and demand allocation in differentiated scenes, and better achieve economy, environmental protection and energy conservation.

Evaluation Study on a Novel Structure CCHP System with a New Comprehensive Index Using Improved ALO Algorithm

The CCHP system is a reasonable and effective method to improve the current situation of energy use. Capacity allocation is of great significance in improving the performance of the CCHP system. Due to the particularity of chemical enterprises’ production process, the demand for cooling, heating, and power load is also relatively particular, which makes the dynamic loads challenging to be satisfied. Because of the above problems, the structure of the typical CCHP system is improved, embodied in the collocation of multi-stage lithium bromide chiller, and the use of various energy storage devices. Based on the improved ant lion intelligent optimization (ALO) algorithm, the comprehensive evaluation index coupled with energy benefit, economic benefit, and environmental benefit, is taken as the objective function, and the equipment capacity configuration of the CCHP system for chemical enterprises is studied. Considering winter, summer, and transition seasons, the results show that the system is better than the typical CCHP system. The annual cost savings of the new structural system are up to 13%, and the carbon dioxide emissions of the new structural system are reduced by up to 36.39%. The primary energy utilization rate of the new structure system is increased by 18%, and the comprehensive evaluation index also performs better. The optimal index can reach 0.814.

Integrated energy system region model with renewable energy and optimal control method

In the context of global energy transition, integrated regional energy systems containing renewable energy sources play an important role. While improving the economic and carbon efficiency of energy utilization, renewable energy sources also bring research challenges to the safe and reliable operation of energy systems. Based on the region concept, a region model and optimal control method for integrated energy systems containing renewable energy are proposed. Firstly, the key pipeline is taken as the observation object, and the feasible region model of the integrated energy system is determined according to the capacity of key equipment and its pipeline capacity with the multi-energy balance equation as the feasible constraint. Then, considering the mutual backup relationship of different equipment and pipelines, the regional integrated energy system security region model is constructed based on the N-1 security criterion, and the optimal control method based on the region concept is proposed. Finally, the validity of the model is analyzed with arithmetic examples, and the influence of the access capacity and access location of renewable energy on the feasible and safe regions of the regional integrated energy system is discussed. And according to the actual situation of the working state point, the optimal adjustment strategy based on the efficiency function and security constraint is given.

Energy Storage Capacity Optimization of Non-Grid-Connected Wind-Hydrogen Systems: From the Perspective of Hydrogen Production Features

This paper intends to improve the hydrogen production efficiency of the electrolysis cells, fully utilize wind energy, and ensure the reliability of power supply. For this purpose, the authors put forward a capacity optimization configuration for non-grid-connected wind-hydrogen hybrid energy storage system, in view of the features of hydrogen production efficiency. The working interval of the electrolytic cell was optimized by analyzing the said features. Considering the features of battery charge/discharge, equipment capacity and power, the authors formulated the energy management strategy applicable to six working conditions, established the quantitative multi-objective function of system cost and reliability, and solved the optimization model by the fast non-dominant sorting genetic algorithm (NSGA)-II. In this way, the optimal combination of energy storage capacity was determined. Next, the wind velocity data of a pastoral area in Inner Mongolia was measured, and analyzed in details. The analysis results show that the electrolytic cell always operates in the optimal working area, and the optimized wind-hydrogen system is economic and reliable in power supply. The research provides a reference for practical engineering applications.

A two-stage optimal scheduling model of integrated energy system based on CVaR theory implementing integrated demand response

A day-ahead and real-time two-stage risk economic optimal model of integrated energy system (IES) is established. First, considering the electricity and heating coupling characteristics of combined heat and power, the feasible region is described by mathematical model, and the integrated demand response model is expanded from the traditional demand response model. Second, the objective functions and constraints of two stages are established respectively. The first stage optimal objective is to minimize the pre-scheduled operation cost of day-ahead, which arranges the output power of renewable energy and the startup-shutdown plan, output power and reserve capacity of adjustable equipment. The second stage optimal objective is to minimize the re-scheduled expected cost of real-time, which will call reserve capacity, curtail renewable energy output, implement integrated demand response, and use energy storage to cope with power deviations. In order to quantify the risk cost of multiple uncertainties of power, load, and price, the real-time stage objective function is further improved to a form of conditional value at risk. Finally, simulations implemented on a green park show that: the proposed model can achieve the optimization of energy supply at different time scales and improve scheduling enforceability after considering economics and risk. Shapely Value can fairly and reasonably determines the benefit distribution scheme of different subjects in IES.

Multi-objective optimization of integrated energy system considering installation configuration

The type, installed capacity and combination of energy equipment significantly affect the investment cost and operation benefits of the integrated energy system (IES). However, the traditional optimization method for IES focuses on the installed capacity of energy equipment, and ignores the impact of type and combination configuration, giving rise to some problems such as low efficiency and energy waste. Against this problem, a multi-objective optimization method based on energy hub (EH) is proposed in this paper, which is focused on the installation configuration of gas turbines. A multi-objective optimization model for determining the installation configuration and operation strategy of equipment is established considering the economy, energy consumption and environmental benefits simultaneously. Then, with a technique for order preference by similarity to an ideal solution (TOPSIS) and entropy weight method to decision making, the ε-constraint-fruit fly optimization algorithm (FOA) are employed to solve the multi-objective optimization model. The results from two modes are compared to illustrate that the mode considering the installation configuration reduces the annual total cost, primary energy consumption and CO2 emissions by 2.03%, 5.43% and 6.76%, respectively, which further proves the effectiveness of the proposed method and the research significance of the installation configuration optimization.

COVID-19: What have we learned?

Since the beginning of the COVID-19 pandemic, the NO-FEAR project focused on using the vast network of the project, for real time exchange of knowledge, in a new and rapidly evolving situation. Lessons observed from a series of twenty webinars around different COVID-19 related topics, that took place during the first two years of the pandemic were processed, analyzed and discussed as part of the NO-FEAR project activity. The findings of the process emphasized the importance of the psychosocial and the human factor in the healthcare systems during the pandemic, and the significant role personal protective equipment stockpile management had on the activity of the healthcare organizations and personnel. The equipment and supply availability and capacity were also an issue considered of high importance. Better incorporating healthcare into crisis management structures was another topic. Finally, strong and good knowledge sharing and links between the healthcare organizations are found to be a useful way for learning from others’ experience and exchanging ideas and practices.

Assessment of Knowledge, Skills, and Preparedness of General-Duty Police on Prehospital Care of Road Traffic Accident Victims in Abuja, Nigeria.

Prompt prehospital care (PHC) is essential for improving outcomes of road traffic accident victims. Previous studies in Nigeria show that little or no PHC is delivered to trauma victims by first responders. This study was conducted to assess police officers' experience with FA/BLS, to identify gaps in their FA/BLS knowledge and skills, and assess police stations' FA/BLS equipment capacity for PHC of road traffic accident victims. This cross-sectional study was conducted among 428 GD police in Abuja between November and December 2018. Respondents were selected using stratified random sampling with proportional allocation method. Data were collected using self-administered electronic semi-structured questionnaires. Data analysis was done using STATA v 14.0 (StataCorp, College Station, TX). Chi-square and multivariate logistic regression were used to assess associations. We analyzed data from 419 respondents. Almost all (90.2%) of the police were aware of FA/BLS. The proportion of police with poor, fair, and good knowledge and skills on FA/BLS were 15.3%, 79.0%, and 5.7%, respectively. Tertiary (OR = 3.35, 95% CI: 1.01-11.11, P = 0.048) and postgraduate (OR = 6.89, 95% CI: 1.63-29.19, P = 0.009) levels of education had statistically significant association with good knowledge and skills. This highlights the need to implement an educational intervention to increase FA/BLS competencies within the first responder population.

Bitlis İli Merkez İlçesindeki Ekmek Fırınlarının Hijyenik Durumu ve Yönetmeliğe Uygunluğu

Bread is a valuable food product that is accepted as a basic food throughout the world and is consumed frequently and lovingly. Bread, which meets a large amount of daily nutritional and energy needs in societies where it is consumed at every meal, has a long-term and labor-intensive production process. The physical structure, the technological equipment capacity, the hygienic condition of the bakeries where the breads are produced, and the professional knowledge and experience of the masters who produce the bread are the important factors affecting the bread quality. This research aimed to evaluate 50 bakeries operating in Merkez district of Bitlis province from different aspects. In this context, the general, technological and hygienic status of the bakeries, the socio-economic status of the personnel working in the bakeries, the compliance of the bakeries with the relevant regulation and the microbial quality of the ambient air in the bakeries were determined. It has been observed that some of the bakeries have negativities and deficiencies in terms of their general, technological and hygienic conditions, and that the social and economic rights of the personnel working in some bakeries are not fully given. In the evaluations made according to the Inspection and Control Form of the Workplaces Producing Food and Food Contact Substances and Materials within the scope of the Regulation on the Inspection and Control of Food Safety and Quality, it has been determined that there are bakeries that are not in compliance with the regulation in terms of some substances. It was determined that the total number of mesophilic aerobic bacteria and yeast-mold counts in the ambient air of the bakeries were below the limits specified in different sources. For healthy and reliable bread production, it is extremely important to provide the necessary technological equipment and hygienic conditions in the bakeries, to produce bread by professionally trained masters, and to regularly implement inspections/controls.

Integrated Saving Matrix - Branch And Bound Method to Optimize Sugar Product’s Distribution Route

The problem in product delivery is always being late and the company has not utilized the capacity of distribution transportation equipment to the fullest. This study aims to determine the shortest distribution route and minimize distribution costs using the Saving Matrix -Branch and Bound methods. In this study, the Saving Matrix method use to produce the shortest route distance, while the Branch and Bound method is applied to optimize a route distance. The results found that the Saving Matrix method followed by the Branch and Bound method reduced routes from the previous seven routes to five routes. Meanwhile, The proposed distribution model shortens the route of 23.6% compared to the current, and cost savings is 23%. To conclude, the model of distribution distance affects the costs savings and optimum route

Optimal Dynamic Operation of Grid-Integrated Hydrogen Energy System: A Techno-Economic Analysis

Rapidly decreasing costs of solar energy and policies that encourage decarbonization are driving solar photovoltaic (PV) farms to be paired with large scale and longer duration energy storage. Hydrogen generation from renewable energy can provide long-term, clean energy storage and can be used in the power industry through fuel cells or combustion turbines, used as chemical feedstock for industry, or as a fuel for transportation. Production costs of hydrogen via electrolytic methods mainly depends on the electricity price, capital costs, and equipment capacity factors. To be cost effective with other types of energy storage, a desired hydrogen price of $1/kg by 2030 will be needed. This study focuses on a techno-economic analysis of a grid-integrated microgrid that includes hydrogen systems (i.e. electrolyzer, compressor, storage tank, and stationary fuel cell), high penetration of solar PV, and battery energy storage systems. The microgrid is operated in a way to minimize the total operation and investment costs and maximize the revenue of the microgrid owner by exchanging power with the grid. While previous work [1] (one hour steady-state time steps) considered a fixed conversion efficiency for the electrolyzer, this study focuses on dynamic operation of the electrolyzer using polarization curves and non-linear conversion efficiency (modeled based on actual cell voltage, cell current, and Faraday efficiency) for more realistic results.Simulation results show that the hourly conversion efficiency of the electrolyzer highly depends on stack operating conditions (cell voltage and current density, the size of the electrolyzer, the temperature, hydrogen demand, etc.). This results in different microgrid optimization and scheduling of energy assets, and consequently the hydrogen production cost. Sensitivity analysis on the PV penetration, current density of the electrolyzer, and changes in asset capital costs will be presented.[1] Hamed Haggi, Paul Brooker, Wei Sun, James M. Fenton, “Hydrogen and Battery Storage Technologies for Low-Cost Energy Decarbonization in Distributed Networks”, arXiv, 11 (2022). https://doi.org/10.48550/arXiv.2202.02711

Ensuring vaccine potency and availability: how evidence shaped Gavi's Immunization Supply Chain Strategy

BackgroundIn 2014, Gavi and partners developed a global Immunization Supply Chain (iSC) Strategy, 2015–2020, which prioritized functioning cold chain equipment (CCE) and additional storage capacity. In 2016, Gavi launched the Cold Chain Equipment Optimization Platform (CCEOP) as a funding mechanism to improve CCE availability. In 2018, Gavi commissioned an evaluation of CCEOP in Guinea, Kenya and Pakistan. The global iSC Strategy has recently been revised, drawing on findings from effective vaccine management assessments and practical experiences. This case study presents the CCEOP evaluation and how its findings reinforced the revision of the iSC strategy.MethodsThe CCEOP evaluation used a prospective mixed-methods research design in all three countries involving key informant interviews at multiple levels of the health system, document reviews, direct observation (as and when possible), and a health facility assessment.ResultsResults show that CCEOP was effective at increasing the number of available and reliable CCE, and establishing improved management processes using the project management team (PMT) approach for country management systems and the service bundle provider approach for installation and maintenance. CCEOP also extended the iSC and immunization services in countries. The evaluation results also show gaps in the overall supply chain system, including CCE maintenance.DiscussionGavi has recently revised its iSC strategy, which has addressed gaps identified through assessments and practical experiences from stakeholders. Results of the CCEOP evaluation reinforce many of these findings. The strategy now provides more emphasis on supporting the fundamental infrastructure and establishing strong processes for maintenance. It also emphasizes strategic planning and forward thinking for iSC decisions, building on the processes established for the PMT through CCEOP. The original iSC strategy was an impetus for the establishment of CCEOP. The new strategy reflects shifting trends and priorities to fill gaps identified through practical experience, advocated for by stakeholders and thought leaders engaged in the iSC, and validated by the evaluation. It demonstrates the importance of aligning stakeholders with clear objectives and a sound strategy.

PET/CT calibration for post-treatment standard body scan acquisition with yttrium-90 resin micro-SPHERES

IntroductionAmong the objectives in treatments with yttrium-90 spheres, is to demonstrate that the tumoricidal dose is achieved and that hepatotoxic doses are avoided, as well as that there is no extrahepatic deposition. Material and methodsWe use different amounts of yttrium-90 resin micro-spheres and a NEMA NU2-2007 phantom to check if the scanner maintains a response that allows real dosimetric calculations. ResultsThe Gemini tomograph responds linearly in a wide range of activities with R2 = 0.9983. ConclusionThe detection capacity of the PET equipment allows us to carry out standard body studies with dosimetric purposes with times of five minutes per bed. It also make possible to verify the absence of extrahepatic deposition of significant amounts of yttrium 90 spheres.

Study on the optimal allocation of comprehensive energy in the park

According to the demand response mode of the user side, this paper divides the flexible load into translational, reducible and transferable loads, briefly analyzes and introduces the operation characteristics of the three loads, and constructs the park comprehensive energy source system including wind power generation, photovoltaic, gas turbine and gas boiler. Considering the system investment cost, operation cost, fuel cost and compensation cost, this paper constructs the optimal allocation model of electric heating system in the park with the optimal total cost, and optimizes it through YALMIP in MATLAB. The final results show that the participation of flexible load and electric heating energy storage can not only effectively reduce the initial investment cost and total system cost in the early stage of the park, but also reasonably adjust the load curve, the optimal output point of energy storage equipment is obtained to determine the capacity of energy storage equipment.

Разработка эффективного водогрейного котла-утилизатора

Introduction. Problems of waste gas heat recovery are relevant in the course production activities. Secondary thermal ener­gy resources are the most widely spread type of energy waste. Efficient recovery of waste heat will reduce energy costs. The building of a cafeteria, that has a water-heating waste heat boiler (WHB) represents a widely spread type of industrial buildings in eastern countries, where hot water and heating can be provided by using heat waste recovered from groups of tandoor furnaces. The purpose of the research is to study unsteady convective flows of heat passing through the pipe of a tandoor heat exchanger and to develop a simple design of a small-sized, easy to manufacture, economical and safe model of a water heating device for the needs of the national economy. Materials and methods. The research is based on a comprehensive methodology employed to study, analyze and gene­ralize thermophysical processes based on the study of convective unsteady heat flows in heat exchanger pipes of tandoor furnaces. Results. The research result represents higher thermal efficiency of the WHB installed in the building of a cafeteria due to the heating, accumulation and heat transfer by vertical finned steel heat-exchanger pipes in the cylindrical boiler in the course of convective heating by the outlet gas used as the heat carrier without returning heat to the water heating boiler. Conclusions. The cafeteria building has scientifically and practically grounded design of a WHB tandoor group, which is a vertical cylindrical tank filled with water, in which vertical outlet heat exchange pipes are placed. Heat, emitted during the operation of tandoors, is used to bake flatbreads and bread by burning wood, coal, natural gas or electric heaters. This heat heats boiler sections to supply hot water to consumers and heat the building premises. The method of finned pipes extends the field of application of the device, increasing the coefficient of heat capacity and heat exchange, as well as the capacity of equipment.

Optimization and Performance Analysis of a Distributed Energy System Considering the Coordination of the Operational Strategy and the Fluctuation of Annual Hourly Load

The operation strategies of a distributed energy system (DES) are usually proposed according to the electrical load (FEL) and the thermal load (FTL), which take the cooling/heating load or electric load as unique constraint conditions that result in a too high or too low equipment load rate. This paper proposes a new hybrid operation strategy (HOS) that takes the full utilization of natural gas and the minimization of power consumption from the power grid as constraints and coordinates the cooling/electricity ratio and heating/electricity ratio of buildings and equipment. In the optimization phase of a DES, an optimization method based on the discretization of the load is proposed to investigate the influence of the uncertainty of the load on the DES, which helps to avoid repeated load simulations and provides stronger adjustability by quoting the normal distribution function to obtain multiple sets of load data with different fluctuations. Further, a multi-objective optimization model combining the genetic algorithm (GA) and mixed integer linear programming algorithm (MILP) was established to find the optimal configuration of equipment capacities by comprehensively considering the annual total cost, carbon emissions, and energy efficiency of the DES. Finally, an office building example was used to validate the feasibility of the above theories and methods. Compared with the FEL and FTL, the HOS reduced the energy waste of the DES by 19.7% and 15.5%, respectively. Compared with using a typical daily load, using an annual hourly load to optimize the DES-HOS produced a better comprehensive performance and lower adverse impacts derived from load fluctuations.

Reliability Evaluation of Standalone Microgrid Based on Sequential Monte Carlo Simulation Method

In order to analyze the influence of uncertainty and an operation strategy on the reliability of a standalone microgrid, a reliability evaluation method based on a sequential Monte Carlo (SMC) simulation was developed. Here, the duty cycles of a microturbine (MT), the stochastic performance of photovoltaics (PV), and wind turbine generators (WTG) were considered. Moreover, the time-varying load with random fluctuation was modeled. In this method, the available capacity of an energy storage system (ESS) was also comprehensively considered by the SMC simulation. Then, the reliability evaluation framework was established from the perspectives of probability, frequency, and duration, and reliability evaluation algorithms under different operation strategies were formulated. Lastly, the influence of WTG and PV penetration and equipment capacity on the reliability was evaluated in the test system. The results showed that the complementary characteristics of wind and solar and the enhancement of the equipment capacity can both improve the reliability; but, with the increase in the penetration rate of WTG and PV, more ESS capacity is needed to cope with the randomness of WTG and PV. In addition, load shedding minimization strategies can minimize the probability and the number of reductions and achieve optimal reliability, which can provide a reference for the formulation of microgrid operation strategies.

Encoding Test Pattern of System-on-Chip (SOC) Using Annular Scan Chain

With the improvement of System-on-Chip integration, the chip requires an increasingly large amount of test data. To solve the contradiction between the storage capacity and bandwidth of automatic test equipment (ATE), a new method of test data compression/decompression is proposed based on an annular scan chain. Corresponding fault bits of different test patterns are incompatible, moving test patterns in an annular scan chain, makes all of the new corresponding bits of different test patterns be compatible or backward-compatible, so different adjacent test patterns form a new relation that are indirectly compatible or indirectly backward-compatible, achieves the purpose of test data compression by encoding these indirectly compatible test patterns or indirectly backward-compatible test patterns. According to experimental results, the average compression ratio increases by %6.94 to % 15.1 compared with the other schemes, relative decompression architecture is simple. In the annular scan chain, the test pattern moves clockwise with the minimal bits, generating subsequent test patterns quickly, it is advantageous to reduce the test application time of a single IP core.

Multi-objective optimization of equipment capacity and heating network design for a centralized solar district heating system

Multi-objective optimization of equipment capacity and heating network design for a centralized solar district heating system

A BCS-GDE multi-objective optimization algorithm for combined cooling, heating and power model with decision strategies

District energy systems can not only reduce energy consumption but also set energy supply dispatching schemes according to demand. In addition to economic cost, energy consumption and pollutant are more worthy of attention when evaluating combined cooling, heating and power (CCHP) models. In this paper, the CCHP model is established with the objective of economic cost, primary energy consumption, and pollutant emissions. The mathematical expression of the CCHP system is proposed, and a multi-objective optimization model with constraints is established. According to different usage requirements, two decision-making strategies are designed, which can adapt to different scenarios. Besides, a generalized differential evolution with the best compromise solution processing mechanism (BCS-GDE) algorithm is proposed to optimize the CCHP model for the first time. The algorithm provides the optimal energy scheduling scheme by optimizing the production capacity of different capacity equipment. The simulation is conducted in three application scenarios: hotels, offices, and residential buildings. The simulation results show that the model established in this paper can reduce economic cost by 72%, primary energy consumption by 73%, and pollutant emission by 88%. Concurrently, the Wilcoxon signed-rank test shows that BCSGDE is significantly better than OMOPSO, NSGA-II, and SPEA2 with greater than 95% confidence.