Energy Efficiency Evaluation Method Research Articles

Research on Energy Efficiency and Carbon Emission Evaluation Methods of cogeneration Technology under the Background of Carbon Neutrality

This article delves into the energy efficiency evaluation methods and carbon emission evaluation methods of cogeneration technology. In terms of energy efficiency evaluation, the concept of energy efficiency and commonly used energy efficiency indicators of cogeneration systems were introduced, such as total energy efficiency, power efficiency, thermal energy efficiency, and fuel utilization efficiency. In terms of carbon emission evaluation, the concept of carbon emissions and commonly used carbon emission indicators for cogeneration systems were analyzed, such as carbon emissions per unit of power generation, carbon emissions per unit of thermal energy, and total carbon emissions. For these evaluation methods, different implementation steps and calculation formulas were introduced in detail, and their application scenarios and advantages and disadvantages were illustrated with examples. These evaluation methods help to evaluate the performance and environmental impact of cogeneration systems, providing scientific basis for relevant decision-making.

Carbon efficiency evaluation method for urban energy system with multiple energy complementary

Urban energy systems (UESs) play a pivotal role in the consumption of clean energy and the promotion of energy cascade utilization. In the context of the construction and operation strategy of UESs with multiple complementary energy resources, a comprehensive assessment of the energy efficiency is of paramount importance. First, a multi-dimensional evaluation system with four primary indexes of energy utilization, environmental protection, system operation, and economic efficiency and 21 secondary indexes is constructed to comprehensively portray the UES. Considering that the evaluation system may contain a large number of indexes and that there is overlapping information among them, an energy efficiency evaluation method based on data processing, dimensionality reduction, integration of combined weights, and gray correlation analysis is proposed. This method can effectively reduce the number of calculations and improve the accuracy of energy efficiency assessments. Third, a demonstration project for a UES in China is presented. The energy efficiency of each scenario is assessed using six operational scenarios. The results show that Scenario 5, in which parks operate independently and investors build shared energy-storage equipment, has the best results and is best suited for green and low-carbon development. The results of the comparative assessment methods show that the proposed method provides a good energy efficiency assessment. This study provides a reference for the optimal planning, construction, and operation of UESs with multiple energy sources.

Energy efficiency and energy-saving evaluation methods for public building energy systems under the dual carbon background

The energy consumption characteristics and energy system structure of each type of building are different, so the evaluation methods and indicators need to be customized for different types of buildings, which increases the complexity of the evaluation. Therefore, a method for evaluating the energy efficiency and energy conservation of public building energy systems under the dual carbon background is proposed. Analyze the coupling coefficient data of energy quality, energy and flow, obtain the base of energy efficiency optimization coefficients, and use twin technology to establish a comprehensive energy efficiency model. Introduce matter element analysis and use matter element extension models to evaluate the energy efficiency and energy-saving effects of public building energy systems. The experimental test results show that the research method can accurately evaluate the energy consumption of public buildings and has an effective evaluation effect on different types of buildings.

Energy Efficiency Evaluation Method for Township Power Users Based on OLAP Technology

With the development of the smart grid and energy Internet, the traditional demand side response is further expanded to the integrated energy management of users, which puts forward higher requirements for the energy management level of users. The energy consumption structure of users has changed greatly. How to measure the rationality of energy consumption, reduce the cost of energy consumption, save energy, and improve efficiency is very important for users. Aiming at the energy efficiency evaluation of township power users, this paper constructs an index system including users’ energy utilization. It also establishes an evaluation method based on the NSGA-III algorithm combined with OLAP technology to measure the closeness between each energy use scheme and the optimal energy use scheme. Finally, through the example analysis and verification, the results indicate that the proposed energy efficiency evaluation method based on OLAP technology is reasonable. Energy efficiency evaluation can meet the needs of information interaction between users and the smart grid, and improve the energy efficiency and energy-saving effect of township power users through energy efficiency evaluation and management.

Inland waterway cargo vessel energy efficiency in operation

Inland waterways vessels (IWV) have no mandatory regulations regarding their energy efficiency, as sea-going ships have. So far, there are just two proposed design energy efficiency evaluation methods, both based on IMO EEDI approach and data on EU inland navigation. Operational indicators and real-time navigation measurements from available literature do not exist. Therefore, this paper aims to introduce the energy efficiency in operation (EEO), assessed for the typical Danube cargo vessel. Firstly, an operational profile is acquired by tracking the vessel’s voyages, and by identifying actual constraints of each sector the vessel has sailed during the designated time. Secondly, EEO is incorporated within two available methods and calculated based on acquired operational data considering different navigational conditions. The paper shows how the energy efficiency vastly depends on variables such as water depth, current speed, draught, deadweight, river constraints. Analysis is performed for the most employed month of the vessel navigation, and annually. Depending on water level scenarios and during the selected month of sailing, the total amount of CO2 emitted is estimated to be between 22.7 t and 29.9 t, while the necessary average speed reduction (i.e., slow steaming) per sectoral voyage for the requirement compliance is calculated to be in between 4.8%-26%. Slow steaming is assessed to extend the time of voyage for 6.1-10.7 hours on monthly basis and 49-87 hours annually.

Energy Efficiency Assessment of Industrial Users Based on Improved TOPSIS Grey Correlation Analysis

In order to improve the energy efficiency of industrial users and evaluate the energy efficiency level before optimizing the energy efficiency of enterprises, an energy efficiency evaluation method based on improved TOPSIS grey relational analysis was proposed to find the weak links in energy use. Firstly, three indexes of energy stability, energy consumption per unit output and carbon emission per unit output are selected to construct the energy efficiency index system. Secondly, the index weights are calculated by entropy weight method, and the energy efficiency levels of industrial users are classified, which can be used by the power grid to implement differentiated electricity prices for high-energy consumption enterprises. Last example city 10 typical energy-intensive enterprise users used improved TOPSIS grey correlation analysis method for evaluation of energy efficiency, energy consumption per unit output value is obtained by analysis of the index weight is the largest, the better the performance of the index, the higher the comprehensive evaluation results of energy efficiency, and finally the method compared with other evaluation methods to verify the effectiveness of the proposed method in this paper.

An energy efficiency evaluation method of intelligent building based on fuzzy clustering algorithm

An energy efficiency evaluation method of intelligent building based on fuzzy clustering algorithm

Energy efficiency evaluation method for power customers based on demand-side response

Energy efficiency evaluation method for power customers based on demand-side response

An energy efficiency evaluation method of intelligent building based on fuzzy clustering algorithm

An energy efficiency evaluation method of intelligent building based on fuzzy clustering algorithm

Energy efficiency evaluation method of refrigeration and air conditioning in intelligent buildings based on improved entropy value method

Energy efficiency evaluation method of refrigeration and air conditioning in intelligent buildings based on improved entropy value method

Energy efficiency evaluation method of refrigeration and air conditioning in intelligent buildings based on improved entropy value method

In order to improve the accuracy and precision of the evaluation of cold source energy efficiency, this paper proposes an evaluation method of cold source energy efficiency of refrigeration and air conditioning in intelligent buildings based on the improved entropy method. On the basis of analysing the energy efficiency ratio composition of refrigeration and air conditioning system, the calculation process of energy efficiency ratio is refined by using refrigeration energy efficiency transport function. Then the AHM improved entropy method was used to optimise the weight ratio process, and the efficient and accurate evaluation of the cooling source energy efficiency of refrigeration and air conditioning was completed by adjusting the weight ratio. The experimental results show that the average evaluation accuracy of the proposed method is 95.9% and the average evaluation accuracy is 96.3%, which proves that the proposed method achieves the design expectation.

Energy efficiency evaluation method for power customers based on demand-side response

Energy efficiency evaluation method for power customers based on demand-side response

On the Development of Science and Technology Finance and the Optimization of Regional Industrial Structure in Anhui

The "double carbon" target that China promised at the UN General Assembly in 2020 puts forward new requirements for the transformation and development of China's energy structure. As an important member of the Yangtze River Delta, Anhui Province lags behind Jiangsu, Zhejiang and Shanghai in terms of energy conservation and carbon reduction. Therefore, it is of great significance to measure the energy use efficiency of Anhui Province in recent years and analyze the influencing factors of energy use efficiency. This paper measures the energy use efficiency of Anhui Province through the single factor and data envelopment analysis of the total factor energy efficiency evaluation method. The empirical results show that: in recent years, the energy economic efficiency of Anhui Province is good, and it is necessary to maintain high energy use efficiency. In order to improve energy efficiency, energy conservation and emission reduction in Anhui Province to promote low-carbon projects, this paper puts forward relevant suggestions.

An integrated energy efficiency evaluation method for forging workshop based on IoT and data-driven

Forging is an industry with high emissions and high energy consumption. Due to the constant increase in the international energy price and the negative impact on the world's environment, researchers have begun to focus on transforming forging into information and sustainable development. However, there remains a substantial gap in the development of the energy management process and energy-efficiency evaluation for complicated forging processes. Therefore, this paper defines a multi-level energy flow model and energy indicators with forging energy characteristics. Then, an energy management system for energy efficiency evaluation is developed based on IoT and data-driven. The energy consumption data are conceived for collection, transmission, storage, processing, mining, and application. Moreover, an integrated energy efficiency evaluation method is detailed with the system energy consumption data. Finally, a case study is carried out to verify the proposal's feasibility and credibility. Through the proposed evaluation method, a forging enterprise can make energy efficiency-optimization decisions.

Energy Efficiency Evaluation and Revenue Distribution of DC Power Distribution Systems in Nearly Zero Energy Buildings

With the advantage of integrating distributed energy, storage and DC load with high efficiency, the DC distribution network recently attracted wide attention in the field of nearly zero energy buildings. Considering the large number of buildings and the enormous energy-saving potential, the distribution form and the revenue distribution are key factors affecting energy efficiency and operational economy. Aiming at the characteristics of AC and DC distribution topologies in nearly zero energy buildings, an energy efficiency evaluation method is proposed based on time-sequential power flow simulation, where the piecewise linear efficiency function of converters and dynamic line power loss model are established. Based on a DC distribution demonstration project, an AC power distribution system with the same boundary conditions is designed. The results show that the efficiency of DC distribution topology is about 6% higher than the AC system, while the efficiency advantage in office, hotel, commercial, educational and residential buildings in Beijing, Shenzhen and Shanghai varies from 0.6–4.96%, which shows a high correlation with the proportion of a high-power load, with Pearson correlation coefficient of 0.794. With the increase of DC load ratio and distributed power supply access capacity, the efficiency of the system will be improved accordingly. On the basis of this, a method to equalize DC distribution income in the nearly zero energy buildings power market is proposed. In addition, 15 typical scenarios of different cities were selected to evaluate efficiency and influencing factors. Finally, assessing the multi-stakeholder impact of DC retrofitting to balance the revenue generated by the DC distribution model suggests that transport costs should be raised by 8.2–13.1% to balance revenue with the equipment prices decreased by about 0.1 yuan/W.

Task-Level Energy Efficiency Evaluation Method Based on Aero-Engine Thrust-Specific Fuel Consumption with Application to Environment Control System

There has recently been a considerable and dramatic change in the system design of some future aircraft. The use of electrical energy has led to a demand for rapid technology development in the environment control system (ECS). Extracting energy from the aero-engine in the form of compressed air and electric power to drive the ECS directly affects aero-engine fuel economy. There is an urgent demand for a task-level energy efficiency evaluation method to guide energy and heat sink scheduling. This paper takes the F22 Raptor fighter jet as the research object and analyzes the influence of bleed air and electric power on the thrust and thrust-specific fuel consumption (TSFC) based on the exergy analysis method. First, a two-step TSFC surrogate model is constructed, and a task-level energy efficiency evaluation method is proposed. The error of the TSFC surrogate model is less than 5%, which means the accuracy of the model is sufficient to meet the needs of engineering. Then, the task-level energy efficiency evaluation results show that the vapor cycle has significant fuel economy when the cooling capacity is large, while the air cycle has certain advantages with a small cooling capacity. The method of TSFC surrogate model reduces computational complexity of evaluation with enough accuracy, which can provide a reference for selecting ECS type and guide the optimization of the cooling capacity distribution of the air cycle and vapor cycle.

Comprehensive energy efficiency study of different climate -adapted BIPV roof forms in single-family houses for five climate zones of China based on PV energy substitution rates (PVESR)

As a type of energy production construction, building integrated photovoltaics (BIPV) roofs are contributing for achieving NZEB goals. Considering building sites’ climate attributes with possible size of PV systems can help to reduce the initial investment and energy consumption of building operation and maintenance. This paper investigates the energy production and energy consumption patterns of single-family houses, which is designed to evaluate the comprehensive energy efficiency of BIPV roofs to meet energy demands by photovoltaic energy substitution ratio (PVESR) calculations. Five typical cities were selected, corresponding to the five climate zones in China; eight forms of BIPV roofs were developed according to single-family houses’ common scale and spatial characteristics. The results show that (1) The PVESR varies significantly between different climate zones and different forms of BIPV roofs, so pre-survey of BIPV roof application sites and comparison of roof forms are relevant in preliminary architecture design. The climate zones where energy balance can be achieved are hot-summer & warm-winter zones, hot-summer & cold-winter zones and moderate zones, and the average PVESR based on the eight roof prototypes are 0.987, 1.136 and 2.272 respectively; the corresponding PVESR for cold zones and severe cold zones are 0.807 and 0.475. (2) The peak and trough values of capacity and energy use are not exactly matching in the five climate zones, especially in severe cold zones, cold zones and hot-summer & cold-winter zones’ winter. (3) The high heating demand in winter is the main reason for the failure to balance BIPV production and energy consumption in severe cold zones and cold zones. The comprehensive energy efficiency evaluation method of BIPV roofs proposed in this paper can provide data support and application guidance for form design and size determination of BIPV roofs in five climate zones in China.

Configuration Generation Method of Ship End Program for Ship Energy Efficiency Management Platform

In order to solve the problem of collecting necessary data affecting fuel consumption and building an intelligent energy efficiency system, this paper makes an in-depth study on the management of cross ship energy efficiency on the basis of program configuration generation. Firstly, this paper studies three methods: technology-driven analysis, support vector machine method, and energy efficiency evaluation method. In order to improve the functions of energy management, energy efficiency analysis, and auxiliary decision-making, this paper constructs a comprehensive intelligent scheme for the best ship navigation energy efficiency from the aspects of ship operation guidance, navigation performance evaluation suggestions, and shipping management decision-making, so as to meet the higher-level management needs of interested parties for ship energy efficiency. Among them, energy efficiency online monitoring can collect energy efficiency data and serve the other three functions, mainly monitoring ship energy consumption, environment, navigation, and other parameters. Energy efficiency evaluation is based on the data collected by online monitoring, and the results of ship energy consumption are obtained by using data mining technology. Through experiments and research, under the background of green, efficient, and intelligent ships, ship shore collaboration is an effective way to improve the ship’s energy efficiency management ability. Intelligent ships provide a new development path for strengthening the application service of ship energy efficiency management system.

User Deep Energy Efficiency Evaluation via Load Perception and Clustering

With the constantly upgrading of the living level of urban residents, the types and quantities of domestic appliances continue to increase, and the electricity consumption behaviour is becoming more and more complex. Based on the fine-grained user energy consumption data obtained by load intelligent perception, this paper proposes a user energy efficiency evaluation method through fuzzy comprehension evaluation. First, the energy consumption characteristics at appliance level which can effectively represent energy consumption behaviour of users are designed and filtered, and then the energy efficiency evaluation strategy of appliances based on fuzzy comprehensive evaluation is established. The strategy adopts two-level fuzzy comprehensive evaluation. The first appliance-level fuzzy evaluation realizes the energy efficiency evaluation of the appliances. The second level is the comprehensive evaluation of user energy efficiency based on the appliance energy efficiency assessment, and the target users are divided into different energy efficiency levels. The measured data-based analysis results prove the effectiveness of the proposed method, and the results can guide users to optimize their electricity consumption behaviour scientifically and realize energy saving and carbon reduction.

Comprehensive Evaluation Method of Energy-saving Effect for Frequency Conversion System Based on Total Harmonic Components

With the development and application of frequency conversion technology,the types of frequency conversion equipment are becoming more and morediverse, and the corresponding energy efficiency testing and evaluation meth-ods are different, which leads to inconsistencies in the selection of equipmentand the operation analysis and evaluation of the frequency conversion system.It is urgent to find an effective solution. By analyzing the problems of thecurrent energy-saving test and evaluation methods of the frequency con-version system, the energy-saving evaluation index system and calculationmethod based on the total harmonic components are proposed. Establish aharmonic evaluation index system covering 9 indicators. On this basis, 6 coreharmonic indicators are selected, and the comprehensive harmonic influencecoefficient and weight matrix are introduced to establish a comprehensive evaluation method for energy-saving effects based on harmonic total com-ponents and weighted matrix model. On this basis, 15 different workingconditions of the energy-saving test and analysis evaluation experiments forof frequency conversion system have been carried out. The results show thatthe total harmonic components analysis method proposed in this paper canreflect the energy efficiency level of the frequency conversion system andits equipments more realistically on the premise of meeting the analysis andactual operation requirements on site. At the same time, the established com-prehensive evaluation method of energy saving effect can comprehensivelyand reasonably analyze the impact of harmonics on the performance of thefrequency conversion system. In addition, it provides theoretical guidance forreasonably determining the optimal operating conditions of the system andequipment, and taking corresponding harmonic prevention measures to effec-tively improve the quality of power transmission and the actual energy-savingeffects of frequency conversion technology.