An energy system carbon footprint analysis method based on input-output balance

Abstract

The application relates to the technical field of energy system analysis, in particular to an energy system carbon footprint analysis method based on input-output balance, which comprises the following steps: obtaining keywords of energy products; collecting target parameters of the energy products to obtain consumption data of the life cycle of the energy products, and performing screening and processing; delivering the obtained consumption data to an input-output model to construct a direct consumption matrix; obtaining the carbon footprint of each energy product by using an input-output balance analysis model; determining whether the life cycle of a single energy product meets a standard, drawing a time-energy consumption curve, and determining whether the life cycle of the single energy product meets the standard based on the slope of the curve; in the application, the consumption data of the energy products is determined based on the keywords of the energy products, the analysis accuracy for the data is improved, the time-energy consumption curve is drawn, the energy consumption condition is analyzed from the time dimension, and the analysis accuracy is further improved.

Description

Technical Field

[0001] This invention relates to the field of energy system analysis technology, and in particular to a method for analyzing the carbon footprint of energy systems based on input-output balance. Background Technology

[0002] The performance evaluation of integrated energy systems can be conducted in various ways, such as energy efficiency analysis, which assesses the overall energy utilization efficiency of the system by calculating the energy conversion efficiency of each link in the system; and economic analysis, which analyzes the economic benefits of the system by evaluating economic indicators such as investment costs, operating costs, and maintenance costs. Existing technologies, combined with newly constructed scoring card models and combined weight values, can evaluate integrated energy systems. While the evaluation results have a certain degree of accuracy, research on evaluation methods for the carbon footprint of various products within the energy system is lacking, especially in dealing with the complex interactions between energy products and the circulation of materials.

[0003] Chinese Patent Application No. CN202410355782.4 discloses a performance evaluation method and apparatus for integrated energy systems. This method, based on a carbon footprint-based PSR model evaluation system, constructs a comprehensive evaluation method based on the AHP-CRITIC method and a scoring card model. This invention combines subjective and objective evaluation results, using a dynamic combined weighting method to couple subjective and objective weights, while simultaneously evaluating the integrated energy system using a newly constructed scoring card model and combined weight values. The scoring card model constructed in this invention can score various indicators and the system as a whole of the integrated energy system. Furthermore, this model is based on logical analysis of actual indicator data, possessing absolute objectivity, and assigning relatively accurate scores to indicators, resulting in evaluation results with a certain degree of accuracy, which is beneficial for the construction and development of future system projects.

[0004] However, the existing technologies still have the following problems: there is a lack of research on evaluation methods for the carbon footprint of various products in the energy system, and the accuracy of analysis is low in dealing with the complex interaction relationships and material flow cycles among energy products. Summary of the Invention

[0005] To address this, the present invention provides a carbon footprint analysis method for energy systems based on input-output balance, which overcomes the lack of existing research on evaluation methods for the carbon footprint of various products within the energy system and the low accuracy in analyzing complex interactions and material flow cycles among energy products.

[0006] To achieve the above objectives, this invention provides a method for analyzing the carbon footprint of energy systems based on input-output balance. It includes:

[0007] Step S1: Obtain keywords for energy products and determine the boundaries of energy products;

[0008] Step S2: Collect target parameters of the energy product based on the determined boundary to obtain the consumption data of the energy product's life cycle, and perform screening processing on the obtained consumption data.

[0009] Step S3: Input the acquired consumption data into the input-output model to construct the direct consumption matrix;

[0010] Step S4: Use the input-output balance analysis model to iteratively process the direct consumption matrix to obtain the final consumption matrix and calculate the carbon footprint of each energy product.

[0011] Step S5: Based on the obtained carbon footprint, determine whether the life cycle of a single energy product meets the standard, plot the time-energy consumption curve, and based on the slope of the curve, determine for the second time whether the life cycle of a single energy product meets the standard.

[0012] Further, in step S5, it is determined whether the life cycle of an individual energy product meets the standard based on the acquired carbon footprint, wherein:

[0013] When a single energy product is initially determined to be non-compliant with the standard based on its life cycle, a secondary determination is made based on the time-energy consumption curve to determine whether it complies with the standard.

[0014] When determining that a single energy product does not meet the standards throughout its life cycle, the reasons for its non-compliance are analyzed based on its carbon footprint.

[0015] Furthermore, based on the average slope of the time-energy consumption curve at each time node, it is determined whether the life cycle of a single energy product meets the standard, wherein:

[0016] When determining that the life cycle of a single energy product does not meet the standard, the collection period is adjusted to the corresponding value based on the average slope.

[0017] Alternatively, if a problem is determined in energy conversion, the judgment criteria can be revised based on the average conversion rate of existing technologies.

[0018] Furthermore, the time interval between each adjacent acquisition cycle is reduced based on the slope difference between the average slope and the first preset average slope, and the slope difference is inversely proportional to the reduction in time interval.

[0019] Furthermore, correction coefficients are determined based on the intervals of each energy conversion rate, and the final correction coefficient α is obtained by weighted summation.

[0020] α=(c1×αi+c2×αi+c3×αi+...+cn×αi) / n,

[0021] Where αi is the i-th correction coefficient, c1 is the weighting coefficient for the first step, and the weighting coefficient here refers to the ratio of the expected consumption in this step to the total consumption in the life cycle of the energy product, and n is the total number of processes in the life cycle of the energy product.

[0022] The preset emissions are corrected to the corresponding value based on the correction factor.

[0023] Furthermore, a process-consumption distribution curve is plotted, and the time interval of the collection cycle of a single energy product is divided into several stages according to the life cycle. The variance of the consumption in each stage is calculated, and the reasons why the life cycle of a single energy product does not meet the standard are determined based on the variance. The reasons include: excessive energy consumption in a single step and problems with data collection.

[0024] Furthermore, the variance of carbon emissions from each process is increased within a preset range, and the increase in variance is directly proportional to the increase in the preset range.

[0025] Compared with the prior art, the beneficial effects of the present invention are that it determines the consumption data of the energy product based on the keywords of the energy product, uses a direct consumption model to analyze the consumption data, improves the accuracy of the data analysis, and draws a time-energy consumption curve to analyze the energy consumption from the time dimension, further improving the accuracy of the analysis.

[0026] Furthermore, this invention analyzes the lifecycle of energy products based on time-energy consumption curves. When the average slope of the curve is small, the lifecycle of a single energy product is deemed qualified; when the slope is large, energy conversion is deemed problematic. The judgment criteria are then corrected, further improving the accuracy of the lifecycle analysis for energy products.

[0027] Furthermore, in this invention, the time interval between acquisition cycles is reduced based on the slope of the curve, thereby increasing the acquisition frequency, improving the control accuracy of data for energy products, and further enhancing the accuracy of life cycle analysis for energy products. Attached Figure Description

[0028] Figure 1 A flowchart of a carbon footprint analysis method for energy systems based on input-output balance;

[0029] Figure 2 A flowchart for initially determining whether the life cycle of a single energy product meets the standards;

[0030] Figure 3 A flowchart for analyzing whether the life cycle of a single energy product conforms to standards;

[0031] Figure 4A flowchart for analyzing why the life cycle of a single energy product does not meet the standards. Detailed Implementation

[0032] To make the objectives and advantages of the present invention clearer, the present invention will be further described below with reference to embodiments; it should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0033] It should be noted that the data in this embodiment are all derived from a comprehensive analysis and evaluation of historical data and corresponding historical judgment results from the six months prior to this judgment by the system described in this invention. Before this test, the system described in this invention comprehensively determines the values ​​of various preset parameter standards for this judgment based on the evaluation values ​​of 37,383 search results accumulated in the previous three months. Those skilled in the art will understand that the system described in this invention can determine the above-mentioned parameters in various ways, such as selecting the value with the highest proportion based on data distribution as the preset standard parameter, using weighted summation to obtain the value as the preset standard parameter, substituting each historical data point into a specific formula and using the value obtained by that formula as the preset standard parameter, or other selection methods, as long as the system described in this invention can clearly define different specific situations in the single-item judgment process through the obtained values.

[0034] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0035] It should be noted that in the description of this invention, the terms "upper", "lower", "left", "right", "inner", "outer", etc., which indicate directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. This is only for the convenience of description and is not intended to indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this invention.

[0036] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0037] Please see Figure 1 As shown, it is a flowchart of a carbon footprint analysis method for energy systems based on input-output balance.

[0038] This invention provides a method for analyzing the carbon footprint of energy systems based on input-output balance, comprising:

[0039] Step S1: Obtain keywords for energy products and determine the boundaries of energy products;

[0040] Step S2: Collect target parameters of the energy product based on the determined boundary to obtain the consumption data of the energy product's life cycle, and perform screening processing on the obtained consumption data.

[0041] Step S3: Input the acquired consumption data into the input-output model to construct the direct consumption matrix;

[0042] Step S4: Use the input-output balance analysis model to iteratively process the direct consumption matrix to obtain the final consumption matrix and calculate the carbon footprint of each energy product.

[0043] Step S5: Based on the obtained carbon footprint, determine whether the life cycle of a single energy product meets the standard, plot the time-energy consumption curve, and based on the slope of the curve, determine for the second time whether the life cycle of a single energy product meets the standard.

[0044] In this invention, the consumption data of an energy product is determined based on its keywords, and a direct consumption model is used to analyze the consumption data, which improves the accuracy of the data analysis. A time-energy consumption curve is plotted to analyze the energy consumption from a time perspective, which further improves the accuracy of the analysis.

[0045] In the manufacturing process of energy products, the production of a particular product is often interactively coupled with the production of multiple other energy products. To accurately determine its carbon footprint, further tracing of these interactions is necessary. For example, the extraction of crude oil and natural gas relies on electrically powered extraction equipment, while diesel fuel and other energy products serve as necessary inputs in the electricity production process. Furthermore, tracing back layer by layer reveals direct or indirect interrelationships among most energy products. Traditional carbon footprint analysis methods struggle to adequately address these issues.

[0046] To solve the above problems, a new matrix balance analysis method proposed by Sun Boxue et al. [1–4] was comprehensively referenced, and input-output analysis proposed by Leontief [5] was also referenced. The basic principle of its calculation is shown in Formula 1.

[0047] Formula 1 is as follows:

[0048]

[0049] In the formula, Represents the total output matrix, Represents the direct demand matrix. Represents the intermediate demand matrix. This represents the final demand matrix.

[0050] Formula 1 can be transformed into Formula 2, as follows:

[0051]

[0052] If matrix Reversible, that is If the spectral radius is less than 1, then Equation 2 can be transformed into the Leont ief inverse matrix, as shown in Equation 3 below:

[0053]

[0054] First, construct the direct demand matrix for the product. Construct the final requirement matrix by combining the product's functional unit matrix. The total output matrix can be calculated using Formula 3. This means that the final consumption matrix can be obtained to obtain the true consumption of the product throughout its entire life cycle. The problems of "cyclic iteration and infinite generation layers" are also solved. At the same time, the carbon footprint level of the energy system can be calculated according to the IPCC carbon emission factor manual.

[0055] According to the China Energy Statistical Yearbook [6], the energy conversion, consumption and output of each industry in China's energy system can be systematically obtained within a certain accounting year. For the problem of coexistence of energy products (for example, multiple products are generated at the same time during the oil refining process), the present invention adopts an energy-based allocation method. The direct demand matrix of unit energy product production is shown in Table 1.

[0056] The calculation process based on energy allocation is shown in Formula 4, where the average lower heating value of each energy product comes from GB / T 2589-2020 General Rules for Calculating Comprehensive Energy Consumption[8], and the production data comes from China Statistical Yearbook[7] and China Energy Statistical Yearbook[6].

[0057] Formula 4 is as follows:

[0058]

[0059] In the formula a i LHV represents the energy distribution coefficient of the symbiotic product. i This indicates the lower heating value of the symbiotic product; P i This indicates the annual production volume of the symbiotic product.

[0060] Based on the application requirements of the model, the spectral radius of the direct demand matrix is ​​calculated. The spectral radius is less than 1, which meets the application requirements of the model. Iterative solution is performed using Formula 3, where the consumption matrix... The values ​​are taken from Direct Demand Matrix Table 1; the final demand matrix is ​​set according to the functional unit settings. The value is taken as the identity matrix I. From this, the final demand matrix of a unit energy product production can be calculated, and the carbon footprint level of each energy product can be calculated according to the IPCC carbon emission factor manual, as shown in Table 2.

[0061]

[0062]

[0063] Please see Figure 2 As shown, it is a flowchart for the preliminary determination of whether the life cycle of a single energy product meets the standards.

[0064] Specifically, in step S5, a preliminary determination method is used to determine whether the life cycle of a single energy product meets the standard based on the acquired carbon footprint, wherein:

[0065] The first preliminary determination method is to determine whether the life cycle of a single energy product meets the standard; the first preliminary determination method satisfies that the carbon footprint is less than or equal to a first preset carbon footprint;

[0066] The second preliminary determination method is to initially determine whether the life cycle of a single energy product does not meet the standard, and then make a secondary determination based on the time-energy consumption curve to determine whether it meets the standard; the second preliminary determination method satisfies that the carbon footprint is greater than the first preset carbon footprint and less than the second preset carbon footprint.

[0067] The third preliminary determination method is to determine that the life cycle of a single energy product does not meet the standard, and to analyze the reasons for its non-compliance based on its carbon footprint; the third preliminary determination method satisfies that the carbon footprint is greater than the second preset carbon footprint.

[0068] In this embodiment of the invention, the first preset carbon footprint is 2.5 tons of carbon dioxide equivalent, and the second preset carbon footprint is 5 tons of carbon dioxide equivalent.

[0069] Please see Figure 3 As shown, it is a flowchart for analyzing whether the life cycle of a single energy product meets the standards.

[0070] Specifically, under the second preliminary determination method, the determination method for whether the life cycle of a single energy product meets the standard is based on the average slope of the time-energy consumption curve at each time node, wherein:

[0071] The first determination method is to determine whether the life cycle of a single energy product meets the standard; the first determination method satisfies that the average slope is less than or equal to the first preset average slope.

[0072] The second determination method is to determine that the life cycle of a single energy product does not meet the standard, and adjust the collection cycle to the corresponding value based on the average slope; the second determination method satisfies that the average slope is greater than the first preset average slope and less than or equal to the second average slope.

[0073] The third determination method is to determine that the life cycle of a single energy product does not meet the standard and that there is a problem with energy conversion. The determination standard is modified based on the average conversion rate of existing technologies. The third determination method satisfies that the average slope is greater than the second preset average slope.

[0074] This invention analyzes the lifecycle of energy products based on time-energy consumption curves. When the average slope of the curve is small, the lifecycle of a single energy product is deemed qualified. When the slope is large, energy conversion is deemed problematic. The judgment criteria are then corrected, further improving the accuracy of lifecycle analysis for energy products.

[0075] Specifically, under the second determination method, the adjustment method for the time interval between each adjacent acquisition cycle is determined based on the slope difference between the average slope and the first preset average slope, wherein:

[0076] The first adjustment method is to select a first adjustment coefficient α1 to adjust the time interval T to the corresponding value, and set the adjusted time interval T' = α1 × T0, where T0 is the initial time interval before adjustment; the first adjustment method satisfies that the slope difference is less than or equal to the preset slope difference.

[0077] The second adjustment method is to select the second adjustment coefficient α2 to adjust the time interval T to the corresponding value, and set the adjusted time interval T' = α2 × T0; the second adjustment method satisfies that the slope difference is greater than the preset slope difference.

[0078] In this embodiment of the invention, the first adjustment coefficient is 0.8, the second adjustment coefficient is 0.75, and the slope difference is 0.7.

[0079] In this invention, the time interval between acquisition cycles is reduced based on the slope of the curve, thereby increasing the acquisition frequency, improving the control accuracy of data for energy products, and further enhancing the accuracy of life cycle analysis for energy products.

[0080] Specifically, under the third determination method, correction coefficients are determined based on the intervals of each energy conversion rate, and the final correction coefficient α is obtained by weighted summation.

[0081] α=(c1×αi+c2×αi+c3×αi+...+cn×αi) / n,

[0082] Where αi is the i-th correction coefficient, c1 is the weighting coefficient for the first step, and the weighting coefficient here refers to the ratio of the expected consumption in this step to the total consumption in the life cycle of the energy product, and n is the total number of processes in the life cycle of the energy product.

[0083] The preset emissions are corrected to the corresponding value based on the correction factor.

[0084] Please see Figure 4 As shown, it is a flowchart for analyzing why the life cycle of a single energy product does not meet the standards.

[0085] Specifically, under the third preliminary judgment method, a process-consumption distribution curve is plotted, the time interval of the collection cycle of a single energy product is divided into several stages according to its life cycle, the variance of consumption in each stage is calculated, and the reason for the non-compliance of the life cycle of a single energy product with the standard is determined based on the variance, wherein:

[0086] The first cause determination method is to determine that a single step has excessive energy consumption; the first cause determination method satisfies the condition that the variance is less than or equal to a preset variance;

[0087] The second cause determination method is to determine that there is a problem with the data collection; the second cause determination method satisfies the condition that the variance is greater than the preset variance.

[0088] In this embodiment of the invention, the preset variance is 23.5.

[0089] Specifically, under the second cause determination method, the variance of carbon emissions from each process increases within a preset range, and the increase in the preset range is proportional to the variance.

[0090] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of the present invention.

[0091] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for analyzing the carbon footprint of an energy system based on input-output balance, characterized in that, include: Step S1: Obtain keywords for energy products and determine the boundaries of energy products; Step S2: Collect target parameters of the energy product based on the determined boundary to obtain the consumption data of the energy product's life cycle, and perform screening processing on the obtained consumption data. Step S3: Input the acquired consumption data into the input-output model to construct the direct consumption matrix; Step S4: Use the input-output balance analysis model to iteratively process the direct consumption matrix to obtain the final consumption matrix and calculate the carbon footprint of each energy product. Step S5: Based on the obtained carbon footprint, determine whether the life cycle of a single energy product meets the standard, plot the time-energy consumption curve, and based on the slope of the curve, determine for the second time whether the life cycle of a single energy product meets the standard. In step S5, based on the acquired carbon footprint, it is determined whether the life cycle of an individual energy product complies with the standard, wherein: When a single energy product is initially determined to be non-compliant with the standard based on its life cycle, a secondary determination is made based on the time-energy consumption curve to determine whether it complies with the standard. When determining that a single energy product does not meet the standards throughout its life cycle, the reasons for its non-compliance are analyzed based on its carbon footprint. The life cycle of a single energy product is determined based on the average slope of the time-energy consumption curve at each time node, where: When determining that the life cycle of a single energy product does not meet the standard, the collection period is adjusted to the corresponding value based on the average slope. Alternatively, if a problem is determined in energy conversion, the judgment criteria can be revised based on the average conversion rate of existing technologies; The time interval between adjacent acquisition cycles is reduced based on the slope difference between the average slope and the first preset average slope. The slope difference is inversely proportional to the reduction in time interval. Correction coefficients are determined based on the range of each energy conversion rate, and the final correction coefficient α is obtained by weighted summation. α=(c1×αi+c2×αi+c3×αi+...+cn×αi) / n, Where αi is the i-th correction coefficient, c1 is the weighting coefficient for the first step, and the weighting coefficient here refers to the ratio of the expected consumption in this step to the total consumption in the life cycle of the energy product, and n is the total number of processes in the life cycle of the energy product. The preset emissions are corrected to the corresponding value based on the correction factor.

2. The energy system carbon footprint analysis method based on input-output balance according to claim 1, characterized in that, The process-consumption distribution curve is plotted, and the time interval of the collection cycle of a single energy product is divided into several stages according to the life cycle. The variance of the consumption in each stage is calculated, and the reasons why the life cycle of a single energy product does not meet the standard are determined based on the variance. The reasons include: excessive energy consumption in a single step and problems with data collection.

3. The energy system carbon footprint analysis method based on input-output balance according to claim 2, characterized in that, The variance of carbon emissions from each process increases within a preset range, and the increase in variance is directly proportional to the increase in the preset range.

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