Method and system for evaluating carbon footprint of whole life cycle of hydropower generation

Abstract

This application provides a method and system for assessing the carbon footprint of hydropower throughout its entire life cycle. It calculates carbon emissions during the vegetation clearing phase based on carbon emissions from energy consumption of construction machinery and equipment used during site clearing and logging, carbon emissions from different vegetation disposal methods after clearing, and the dynamic loss of ecological carbon sequestration capacity. The total carbon emissions for the entire life cycle of hydropower are obtained based on carbon emissions during the vegetation clearing phase, the raw material and equipment acquisition phase, the hydropower station construction phase, the operation and maintenance phase, and the decommissioning and recycling phase. The carbon footprint assessment level is determined based on the calculated carbon footprint factor per unit of electricity generation, the proportion of carbon emissions from vegetation ecological disturbance, and the structural deviation during the operation and maintenance phase. This method more accurately measures the net carbon emissions during the vegetation clearing phase and their impact on the cumulative carbon footprint throughout the entire life cycle of hydropower, thus achieving more precise carbon footprint accounting and assessment.

Description

Technical Field

[0001] This invention relates to the field of carbon footprint assessment technology, and in particular to a method and system for assessing the carbon footprint of hydropower throughout its entire life cycle. Background Technology

[0002] As global climate change becomes increasingly severe, promoting a green and low-carbon transformation has become a general consensus in the international community. Currently, there is an advocacy for the development of clean energy sources such as hydropower, tailored to local conditions. However, hydropower is not an absolutely "zero-carbon emission" energy source. Its entire life cycle encompasses multiple stages, including material and equipment production, transportation, construction, reservoir impoundment, and biodegradation, and may still generate greenhouse gases that cannot be ignored.

[0003] In the current context, the lack of a systematic and accurate carbon footprint accounting system makes it difficult to objectively and accurately assess the true carbon footprint level and clean attributes of hydropower projects throughout their entire life cycle. Furthermore, at the application level, there is a lack of evaluation rules that match the accounting results. A low-carbon performance evaluation system capable of jointly assessing overall carbon emission levels, the intensity of pre-construction ecological disturbance, and the structural rationality during the operation phase has not yet been established. This makes it difficult for carbon footprint accounting results to further serve the low-carbon planning and emission reduction pathway identification of hydropower projects. Summary of the Invention

[0004] The technical problem to be solved by this invention is to provide a method and system for evaluating the carbon footprint of hydropower throughout its entire life cycle, which can more accurately realize carbon footprint accounting and evaluation.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A method for assessing the carbon footprint of hydropower throughout its entire life cycle includes: Carbon emissions during the vegetation clearing phase are calculated based on the carbon emissions generated by the energy consumed by construction machinery and equipment used in the site clearing and logging process, the carbon emissions generated by different vegetation disposal methods after vegetation clearing, and the dynamic loss of ecological carbon sequestration capacity. The total carbon emissions of hydropower generation throughout its entire life cycle are obtained from the carbon emissions during the vegetation clearing phase, the raw material and equipment acquisition phase, the hydropower station construction phase, the operation and maintenance phase, and the decommissioning and recycling phase. Calculate the carbon footprint factor per unit of electricity generated based on the total carbon emissions; The proportion of carbon emissions from vegetation ecological disturbance is calculated based on the total carbon emissions and the carbon emissions from the vegetation clearing phase. The structural deviation of the operation and maintenance phase is calculated based on the total carbon emissions and the carbon emissions of the operation and maintenance phase. The carbon footprint evaluation level is determined based on the carbon footprint factor per unit of electricity generation, the proportion of carbon emissions from vegetation ecological disturbance, and the structural deviation of the operation and maintenance phase.

[0006] To solve the above-mentioned technical problems, another technical solution adopted by the present invention is as follows: A hydropower generation life-cycle carbon footprint assessment system includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the various steps of the aforementioned hydropower generation life-cycle carbon footprint assessment method.

[0007] The beneficial effects of this invention are as follows: It calculates carbon emissions during the vegetation clearing stage based on the carbon emissions generated by the energy consumed by construction machinery and equipment used in site clearing and logging, carbon emissions generated by different vegetation disposal methods after vegetation clearing, and the dynamic loss of ecological carbon sequestration capacity. It obtains the total carbon emissions for the entire life cycle of hydropower generation based on carbon emissions during the vegetation clearing stage, the raw material and equipment acquisition stage, the hydropower station construction stage, the operation and maintenance stage, and the decommissioning and recycling stage. It calculates the carbon footprint factor per unit of power generation based on the total carbon emissions. It calculates the proportion of carbon emissions due to vegetation ecological disturbance based on the total carbon emissions and the carbon emissions during the vegetation clearing stage. It calculates the structural deviation degree during the operation and maintenance stage based on the total carbon emissions and the carbon emissions during the operation and maintenance stage. Finally, it calculates the carbon footprint factor per unit of power generation, the proportion of carbon emissions due to vegetation ecological disturbance, and the carbon footprint factor per unit of power generation, the proportion of carbon emissions due to vegetation ecological disturbance, and the carbon emissions during the operation and maintenance stage. The structural deviation during the operation and maintenance phase determines the carbon footprint assessment level. This allows for a comprehensive consideration of direct energy consumption during vegetation clearing operations, differentiated biomass disposal carbon emissions from different post-clearing destinations, and ecological carbon sink losses caused by vegetation clearing when calculating total carbon emissions. This approach more accurately reflects the actual project situation and measures the net carbon emissions during the vegetation clearing phase and its impact on the cumulative carbon footprint throughout the hydropower generation's life cycle. Furthermore, it establishes three core evaluation indicators based on three dimensions: overall emission level, pre-construction ecological disturbance intensity, and structural rationality during the operation phase. These indicators include the carbon footprint factor per unit of power generation, the proportion of carbon emissions from vegetation ecological disturbance, and the structural deviation during the operation and maintenance phase. This enables a quantitative interpretation of the project's low-carbon characteristics without relying on a single comprehensive total score, thus achieving more precise carbon footprint accounting and evaluation. Attached Figure Description

[0008] Figure 1 This is a flowchart of a method for evaluating the carbon footprint of hydropower throughout its entire life cycle, according to an embodiment of the present invention. Figure 2 This is a schematic diagram of different vegetation treatment methods in a method for evaluating the carbon footprint of hydropower throughout its entire life cycle, according to an embodiment of the present invention. Figure 3This is a comparison diagram of different schemes for evaluating the life cycle carbon footprint of hydropower stations with different vegetation disposal methods in an embodiment of the present invention. Figure 4 This is a diagram showing the carbon emissions and their percentages at each stage in a hydropower lifecycle carbon footprint assessment method according to an embodiment of the present invention. Figure 5 This is a schematic diagram of a hydropower generation life-cycle carbon footprint assessment system according to an embodiment of the present invention. Detailed Implementation

[0009] Definitions:

[0010] To explain in detail the technical content, objectives, and effects of the present invention, the following description is provided in conjunction with the embodiments and accompanying drawings.

[0011] Existing technologies for calculating the carbon footprint of hydropower projects throughout their entire life cycle do not adequately consider carbon emissions and carbon sink losses caused by ecological disturbances during site preparation and operation / maintenance. They lack a systematic accounting framework covering the entire process, making it difficult to comprehensively reflect the true carbon emissions throughout the hydropower project's life cycle. Specifically, during the site preparation phase before power plant construction, vegetation clearing within the site selection area removes existing plant communities, disrupting their carbon sequestration and storage functions and causing a loss of vegetation biomass carbon storage. Existing accounting methods typically only focus on the mechanical energy consumption and direct emissions during the clearing process, lacking systematic measurement of the reduction in carbon storage, loss of carbon sink capacity, and subsequent carbon release processes under different disposal methods caused by vegetation clearing. This leads to omissions in the accounting of carbon emissions during the pre-construction phase. Furthermore, existing research on the carbon footprint of hydropower remains at the level of "total accounting." Even when full life-cycle carbon emission results are obtained, they typically only provide a static display of the total carbon footprint or the carbon emission factor per unit of electricity generation. There is a lack of evaluation standards geared towards engineering applications, making it difficult to further determine the overall low-carbon performance of the project. It is also difficult to identify whether pre-construction ecological disturbances, long-term cumulative emissions during operation, or other factors constitute the dominant influence on the project's low-carbon performance. Especially for different projects, due to variations in accounting boundaries, parameter sources, and stage division methods, relying solely on total results makes it difficult to form unified, interpretable, and comparable evaluation conclusions.

[0012] Therefore, existing methods not only have omissions at the accounting boundary, but also lack evaluation rules that match the accounting results at the application level. A low-carbon performance evaluation system that can jointly determine the overall carbon emission level, the intensity of ecological disturbance before construction, and the structural rationality during the operation phase has not yet been established, making it difficult for the carbon footprint measurement results to further serve the low-carbon planning and emission reduction path identification of hydropower projects.

[0013] To at least address the aforementioned issues, carbon emissions during the vegetation clearing phase are calculated based on the carbon emissions generated by energy consumption of construction machinery and equipment used in site clearing and logging, carbon emissions generated by different vegetation disposal methods after vegetation clearing, and the dynamic loss of ecological carbon sequestration capacity. The total carbon emissions for the entire lifecycle of hydropower generation are obtained based on carbon emissions during the vegetation clearing phase, the raw material and equipment acquisition phase, the hydropower station construction phase, the operation and maintenance phase, and the decommissioning and recycling phase. The carbon footprint factor per unit of electricity generation is calculated based on the total carbon emissions. The proportion of carbon emissions due to vegetation ecological disturbance is calculated based on the total carbon emissions and the carbon emissions during the vegetation clearing phase. The structural deviation degree of the operation and maintenance phase is calculated based on the total carbon emissions and the carbon emissions during the operation and maintenance phase. Finally, the carbon footprint evaluation level is determined based on the carbon footprint factor per unit of electricity generation, the proportion of carbon emissions due to vegetation ecological disturbance, and the structural deviation degree of the operation and maintenance phase. This approach allows for a comprehensive consideration of direct energy consumption during vegetation clearing operations, differentiated biomass disposal carbon emissions from different post-clearing destinations, and ecological carbon sink losses caused by vegetation clearing when calculating total carbon emissions. This more accurately reflects the actual situation of the project and more precisely measures the net carbon emissions during the vegetation clearing phase and its impact on the cumulative carbon footprint throughout the entire life cycle of hydropower generation. Furthermore, it sets three core evaluation indicators around three dimensions: overall emission level, pre-construction ecological disturbance intensity, and structural rationality during the operation phase. These indicators include the carbon footprint factor per unit of power generation, the proportion of carbon emissions from vegetation ecological disturbance, and the structural deviation during the operation and maintenance phase. This enables a quantitative interpretation of the project's low-carbon characteristics without relying on a single comprehensive total score, thus achieving more accurate carbon footprint accounting and evaluation.

[0014] The following details a method for assessing the carbon footprint of hydropower throughout its entire life cycle, as described in this invention. Please refer to [link / reference]. Figure 1 The method 100 includes steps 101 to 106: Step 101: Calculate the carbon emissions during the vegetation clearing stage based on the carbon emissions generated by the energy consumed by construction machinery and equipment used in site clearing and logging, the carbon emissions generated by different vegetation disposal methods after vegetation clearing, and the dynamic loss of ecological carbon sequestration capacity. Specifically: ; In the formula, This refers to the carbon emissions generated by the energy consumed by construction machinery and equipment used in site clearing and logging processes. This indicates the carbon emissions generated by different vegetation disposal methods after vegetation clearing. This indicates the dynamic loss of ecological carbon sequestration capacity.

[0015] Step 102: Based on the carbon emissions during the vegetation clearing phase, the raw material and equipment acquisition phase, the hydropower station construction phase, the operation and maintenance phase, and the decommissioning and recycling phase, the total carbon emissions for the entire life cycle of hydropower generation are obtained, specifically as follows: ; In the formula, This represents the total carbon emissions over the entire life cycle of hydropower generation. This indicates carbon emissions during the vegetation clearing phase. This indicates carbon emissions during the raw material and equipment acquisition phase. This indicates carbon emissions during the construction phase of a hydropower station. This indicates carbon emissions during the operation and maintenance phase. This indicates carbon emissions during the decommissioning and recycling phase.

[0016] Step 103: Calculate the carbon footprint factor per unit of electricity generation based on the total carbon emissions.

[0017] Step 104: Calculate the proportion of vegetation ecological disturbance carbon emissions based on the total carbon emissions and the carbon emissions during the vegetation clearing phase, specifically as follows: ; In the formula, This indicates the proportion of carbon emissions caused by vegetation ecological disturbance.

[0018] The vegetation ecological disturbance carbon emission ratio is used to characterize the proportion of ecological disturbance carbon emissions formed by pre-construction vegetation clearing, differentiated vegetation treatment and carbon sink loss in the total carbon footprint. The larger the value, the stronger the ecological disturbance before project construction and the lower the low carbon nature.

[0019] Step 105: Calculate the structural deviation of the operation and maintenance phase based on the total carbon emissions and the carbon emissions of the operation and maintenance phase, specifically as follows: ; In the formula, This indicates the degree of structural deviation during the operation and maintenance phase. This represents the average reference value during the operation and maintenance phase of similar hydropower projects. In one optional implementation, .

[0020] The structural deviation during the operation and maintenance phase is used to characterize the degree of deviation of the carbon emission ratio during the operation and maintenance phase of this project from the typical structure of similar hydropower projects. The smaller the deviation, the closer the life cycle structure of this project is to the common distribution of similar hydropower projects, and the higher the structural rationality.

[0021] Step 106: Determine the carbon footprint evaluation level based on the carbon footprint factor per unit of electricity generation, the proportion of carbon emissions from vegetation ecological disturbance, and the structural deviation of the operation and maintenance phase.

[0022] The purpose of setting the above evaluation indicators is not to mechanically compress indicators with different physical meanings into a single total score, but to jointly determine the low-carbon performance of hydropower stations through three dimensions: "overall emission level - intensity of ecological disturbance before construction - structural rationality during operation". The carbon footprint factor per unit of power generation is used to judge the overall carbon emission intensity level of the project, the proportion of carbon emissions from vegetation ecological disturbance is used to identify the degree of reduction of the total carbon footprint by ecological disturbance before construction, and the structural deviation degree during operation and maintenance is used to judge whether the structure during operation deviates from the typical distribution of similar hydropower projects.

[0023] In one embodiment of the present invention, steps 201 to 206 are included before step 101: Step 201: Obtain the energy quality and corresponding carbon emission factors of the construction machinery and equipment used in the vegetation clearing stage.

[0024] Step 202: Calculate the carbon emissions generated by the energy consumed by construction machinery and equipment used in site clearing and logging processes based on the energy quality and the carbon emission factor, specifically as follows: ; In the formula, This indicates the number of different types of energy consumed by construction machinery and equipment used during the vegetation clearing phase. This indicates the consumption of construction machinery and equipment during the vegetation clearing phase. i Energy mass, measured in tons (t). This indicates the consumption of construction machinery and equipment during the vegetation clearing phase. i The carbon emission factor of this energy source is expressed in tCO2e / t.

[0025] in, Calculated based on the fuel consumption and electricity usage records of construction machinery, or the rated fuel consumption of the equipment. Determined based on the emission factor database corresponding to the energy type and the country or industry.

[0026] Step 203: Calculate the carbon emissions from combustion and the carbon emissions from wood utilization.

[0027] Step 204: Calculate the carbon emissions generated by different vegetation disposal methods after vegetation clearing based on the carbon emissions from combustion and the carbon emissions from wood utilization. Specifically: ; In the formula, Indicates carbon emissions from combustion. This indicates the carbon emissions from timber utilization.

[0028] like Figure 2 As shown, Figure 2The exhibition showcased different methods of vegetation disposal, including processing into wood products, burning on-site, and storing or submerging in the reservoir area.

[0029] Step 205: Obtain the vegetation area submerged by the reservoir, the carbon sequestration capacity of vegetation per unit area per unit time, the life cycle of the hydropower station, the area of ​​vegetation occupied by temporary construction land, and the recovery delay time required after the temporary land occupation ends.

[0030] Step 206: Calculate the dynamic loss of ecological carbon sequestration capacity based on the vegetation area submerged by the reservoir, the carbon sequestration capacity of vegetation per unit area per unit time, the lifespan of the hydropower station, the area of ​​vegetation occupied by the temporary construction site, and the recovery delay time required after the temporary site is completed. Specifically: ; In the formula, This indicates the number of vegetation species submerged by the reservoir. Indicates the first flood of the reservoir i Area of ​​vegetation type Represents the unit area per unit time. i Carbon sequestration capacity of vegetation Indicates the lifespan of a hydropower station. This indicates the number of vegetation types occupied by the temporary construction site. Indicates the area occupied by temporary construction land. i Area of ​​vegetation-like vegetation This indicates the recovery delay time required after the temporary occupation ends, that is, the recovery delay time required for vegetation restoration measures to restore the original carbon sequestration level after the temporary occupation ends.

[0031] in, and Obtained from analysis of reservoir inundation lines, construction red lines, etc. Regional ecosystem carbon sink monitoring values ​​should be used preferentially. It is determined based on the construction and revegetation plan and the results of the revegetation monitoring.

[0032] In one embodiment of the present invention, step 203 includes: To obtain vegetation biomass and vegetation carbon content; The carbon emissions from combustion and carbon emissions from wood utilization are calculated based on the vegetation biomass and the vegetation carbon content, specifically as follows: ; ; In the formula, This indicates the number of vegetation species that were burned. The first one that was burned i Vegetation biomass The first one that was burnedi Carbon content of vegetation This indicates the number of vegetation species used for timber. The first is used as timber. j Vegetation biomass The first is used as timber. j Carbon content of vegetation The first is used as timber. j The decay constant of vegetation-like structures.

[0033] Among them, vegetation biomass The calculation formula is: ; In the formula, n Indicates the number of vegetation species. This represents the area covered by each type of vegetation, in hectares (hm²). 2 , This represents vegetation biomass density, expressed in t / hm². 2 .

[0034] Determined through remote sensing imagery, land use maps, and on-site boundary surveying. Determined through regional forest resource inventory, sample plot surveys, or literature data from the same region. , Sample test results will be used first; if the results are missing, the default carbon content of the vegetation type will be used. Select according to the type of wood product or its service life.

[0035] As described above, the vegetation clearing phase not only considers the direct energy consumption of the operation process, but also profoundly reveals the indirect carbon emissions caused by land use change. The total carbon emissions generated include three parts: the first part is the direct carbon emissions generated by the energy consumed by the construction machinery and equipment used in the site clearing and logging process; the second part is the carbon emissions from the differentiated biomass disposal after vegetation clearing based on different destinations. For example, the carbon release of vegetation transported out to be made into timber products follows a slow, delayed process of exponential decay, while the carbon release of vegetation burned in situ is counted as an immediate release; the third part is the dynamic loss of ecological carbon sequestration capacity (i.e., carbon sink), which accurately covers the background carbon sequestration capacity lost by vegetation in the permanently submerged area of ​​the reservoir during the entire hydropower generation cycle, as well as the carbon sequestration loss generated by vegetation destroyed by temporary construction land occupation during the ecological restoration delay period. This makes up for the traditional model's neglect of the impact of vegetation status on carbon emission accounting, and the accounting results are more comprehensive and accurate. It realizes a panoramic quantification of the carbon footprint of the entire life cycle from the source of vegetation destruction to the final decommissioning of the power station, which is more in line with the actual physical process.

[0036] In one embodiment of the present invention, steps 301 to 304 are included before step 102: Step 301: Calculate the carbon emissions during the raw material and equipment acquisition stage based on the required quantities of raw materials and equipment acquired in the raw material and equipment acquisition stage and their corresponding carbon emission factors. Specifically: ; In the formula, This indicates the number of types of raw materials and equipment acquired during the raw material and equipment acquisition stage. Indicates the obtained first i The required quantity of raw materials and equipment. Indicates the obtained first i Carbon emission factors of raw materials and equipment.

[0037] in, Obtain these documents through equipment purchase contracts, delivery acceptance forms, equipment nameplates, and completed equipment ledgers. Priority should be given to using the manufacturer's environmental product declaration, life cycle assessment report, or carbon emission accounting data of the manufacturing enterprise. When these are not directly available, emission factors of similar equipment should be matched and converted based on the equipment model, capacity level, material composition, and manufacturing process in industry databases or publicly available life cycle assessment literature.

[0038] The raw materials and equipment acquisition stage focuses on the implicit carbon emissions of the upstream supply chain and incorporates industrial production outside the system boundary into the accounting system.

[0039] Step 302: Calculate the carbon emissions during the construction phase of the hydropower station based on the carbon emissions generated during the construction process and the carbon emissions generated during the transportation process. Specifically: ; ; ; In the formula, This indicates the carbon emissions generated during the construction process. This indicates the total number of types of building materials and energy involved in the construction process. Indicates the first stage of construction i The usage / consumption of building materials or energy Indicates the first stage of construction i Carbon emission factors corresponding to building materials or energy sources, This indicates the carbon emissions generated during the transportation process. This indicates the number of different types of transportation vehicles during the transportation process. Indicates the first step in the transportation process i The transport mileage of this type of transport vehicle Indicates the first step in the transportation process i Carbon emission factors of similar transportation vehicles Indicates the first step in the transportation processi The weight of goods transported by a type of transport vehicle.

[0040] in, The quantities are determined based on the construction drawing budget, material entry and exit records, settlement statement, and final settlement of the project. Prioritize the use of material suppliers' environmental product statements or factors from national, industry, and regional building materials databases; Determined based on logistics documents, transportation routes, or GIS (Geographic Information System) distance measurement. Based on the weighbridge slip, component list, and packing list, The emission factor per ton-kilometer is determined according to the type of transportation vehicle, with priority given to the actual energy consumption of the carrier. If the actual energy consumption cannot be obtained, the industry average factor is used.

[0041] The construction phase of a hydropower station encompasses both on-site assembly of various production facilities and transportation of building materials, resulting in carbon emissions. Therefore, its carbon emissions consist of two parts: one part is the carbon emissions generated by large equipment such as cranes consuming fuel oil or electricity during the on-site construction of various production facilities; the other part is the carbon emissions generated by different transportation vehicles consuming coal or electricity during the transportation of building materials such as steel bars and cement, based on a detailed calculation of the vehicle's power type.

[0042] Step 303: Calculate the carbon emissions during the operation and maintenance phase based on the carbon emissions from energy and material consumption, the carbon emissions from energy consumption and replacement of critical electrical equipment during operation, and the greenhouse gas emissions from the reservoir. Specifically: ; ; ; ; In the formula, This indicates carbon emissions generated from energy and material consumption. This indicates the energy consumption and carbon emissions generated during the operation and replacement of critical electrical equipment. Indicates greenhouse gas emissions from the reservoir. This indicates the number of types of energy or materials used in operation and maintenance. Indicates the first stage of operation and maintenance. i Energy or material consumption Indicates the first stage of operation and maintenance. i Carbon emission factors of energy or materials Indicates service life. Indicates no-load loss. Indicates the average load factor. Indicates the rated load loss. Indicates the annual running time. Indicates the first t Annual grid carbon emission factor This indicates the number of pieces of equipment (such as transformers) that need to be replaced. This indicates the total number of batches of equipment replaced or updated during the lifespan of a hydropower station. Indicates the lifespan of a hydroelectric power station. Indicates the surface area of ​​the reservoir. Indicates carbon dioxide i Annual carbon emission flux per unit area. This represents the global warming potential of methane. Indicates methane i Annual carbon emission flux per unit area. This represents the global warming potential of nitrous oxide. It represents the first nitrous oxide i Annual carbon emission flux per unit area.

[0043] in, Based on the plant's electricity usage, meter readings, spare parts requisition forms, sulfur hexafluoride gas replenishment records, and maintenance logs during the operation and maintenance period; Determined based on the country / industry factor of the corresponding energy or material. , , and Priority should be given to obtaining information from equipment nameplates, factory test reports, and operation and maintenance technical documents; Obtained from historical load curves, dispatch operation records, or annual average load rate statistics; Determined based on annual operating hours; The power grid emission factor is taken annually according to the region where the power plant is located. If there are missing years, interpolation from adjacent years or the most recent year's value is used. For , , , The above parameters are preferably obtained through actual measurements at the reservoir: The data are determined based on the reservoir surface line or hydrological and topographic data at the normal water level; the fluxes of the three types of greenhouse gases are preferentially obtained by using the floating box method, static box method, or water-gas interface flux monitoring results, and the annual average value is obtained by combining the monitoring data of the wet and dry seasons and the regional and stratified monitoring data; when long-term monitoring series are lacking, the early high emission and later decline trends can be piecewise fitted by combining the years of operation, or the corrected flux data of reservoirs in the same climate zone and reservoir type can be used for correction.

[0044] The operation and maintenance phase is lengthy, influenced by numerous factors, and exhibits a clear long-term cumulative characteristic in carbon emissions. Carbon emissions during this phase originate from greenhouse gas emissions caused by the operation and maintenance of the hydropower station during its service life, the continuous operation and replacement of critical electrical equipment, and chemical reactions occurring in the reservoir inundation area. To comprehensively reflect the actual carbon emissions during the operation and maintenance phase, these emissions are divided into three parts: first, carbon emissions generated by the consumption of various energy and materials during operation and maintenance; second, carbon emissions corresponding to no-load losses, load losses, and replacement of critical electrical equipment during its lifespan; and third, carbon emissions generated by the decomposition of organic matter in the reservoir inundation area, releasing greenhouse gases such as carbon dioxide, methane, and nitrous oxide.

[0045] Step 304: Calculate the carbon emissions during the decommissioning and recycling phase based on the carbon emissions generated during dismantling, transportation, and waste disposal. Specifically: ; ; ; ; In the formula, This indicates the carbon emissions generated during the dismantling process. This indicates the number of types of energy used in the dismantling of large equipment. Indicates the first [item] used in the disassembly process for large equipment. i Energy consumption Indicates the first [item] used in the disassembly process for large equipment. i Energy-like carbon emission factors This indicates the carbon emissions generated by recyclable waste. This indicates the ratio of recycled materials to raw materials; the negative sign represents equivalent carbon absorption. This indicates the carbon emissions generated by non-recyclable waste. Indicates the number of types of non-recyclable waste. Indicates the first i The amount of non-recyclable waste that is landfilled or incinerated. Indicates the first i Carbon emission factors of non-recyclable waste The carbon emissions generated during the transportation process are calculated in the same way as... The same applies, so I won't repeat it here.

[0046] in, Determined based on the decommissioning and demolition plan, construction machinery configuration plan, and fuel consumption quota; Emissions are obtained based on the emission factors corresponding to the energy type of the dismantled equipment. The determination is based on the material type, on-site sorting purity, recycling channels for renewable resources, and the industry's recycling rate. The non-recyclable portion of the total waste after deducting the recyclable portion; Priority should be given to using factors measured / reported by incinerators, landfills, or resource utilization enterprises. If these factors are missing, the industry average factor corresponding to the disposal method should be used.

[0047] The decommissioning and recycling phase marks the completion of the life cycle. Apart from the energy consumption of dismantling machinery and logistics transportation, the core lies in the differentiated disposal of waste. Therefore, its carbon emissions include three parts: first, the carbon emissions generated by the energy consumption of large equipment used in the dismantling process; second, the carbon emissions generated by the transportation vehicles used to transport the waste to its destination; and third, the treatment of waste, which can be divided into recyclable waste and non-recyclable waste according to different types of waste.

[0048] As described above, dividing the entire life cycle of hydropower into carbon emissions generated during the vegetation clearing stage, carbon emissions generated during the raw material and equipment acquisition stage, carbon emissions generated during the hydropower station construction stage, carbon emissions generated during the operation and maintenance stage, and carbon emissions generated during the decommissioning and recycling stage allows for a more comprehensive and accurate calculation of the carbon footprint of hydropower across the entire ecosystem.

[0049] In one embodiment of the present invention, step 103 includes steps 1031 to 1032: Step 1031: Obtain the total power generation of hydropower throughout its entire life cycle.

[0050] Step 1032: Calculate the carbon footprint factor per unit of electricity generation based on the total electricity generation over the entire life cycle of the hydropower project and the total carbon emissions. Specifically: ; In the formula, This represents the carbon footprint factor per unit of electricity generated. This represents the total power generation of hydropower throughout its entire life cycle.

[0051] As described above, calculating the carbon footprint factor per unit of electricity generated based on the total electricity generation and total carbon emissions throughout the entire life cycle of hydropower can effectively characterize the carbon emission intensity corresponding to a unit of electricity generated.

[0052] In one embodiment of the present invention, step 106 includes steps 1061 to 1064: Step 1061: Determine the carbon emission intensity level based on the carbon footprint factor per unit of electricity generated.

[0053] Specifically, if the carbon footprint factor per unit of electricity generation is less than or equal to a first preset value, the carbon emission intensity is determined to be low; if the carbon footprint factor per unit of electricity generation is greater than the first preset value and less than or equal to a second preset value, the carbon emission intensity is determined to be low; if the carbon footprint factor per unit of electricity generation is greater than the second preset value and less than or equal to a third preset value, the carbon emission intensity is determined to be medium; and if the carbon footprint factor per unit of electricity generation is greater than or equal to a third preset value, the carbon emission intensity is determined to be high.

[0054] The first preset value, the second preset value, and the third preset value increase sequentially. In one optional embodiment, the first preset value is 7.98, the second preset value is 14.77, and the third preset value is 24.21.

[0055] Step 1062: Determine the ecological disturbance level based on the proportion of carbon emissions from vegetation ecological disturbance.

[0056] Specifically, if the proportion of carbon emissions from vegetation ecological disturbance is less than or equal to a first preset percentage, the ecological disturbance is determined to be small; if the proportion of carbon emissions from vegetation ecological disturbance is greater than the first preset percentage and less than or equal to a second preset percentage, the ecological disturbance is determined to be relatively small; if the proportion of carbon emissions from vegetation ecological disturbance is greater than the second preset percentage and less than or equal to a third preset percentage, the ecological disturbance is determined to be moderate; and if the proportion of carbon emissions from vegetation ecological disturbance is greater than the third preset percentage, the ecological disturbance is determined to be significant.

[0057] The first preset percentage, the second preset percentage, and the third preset percentage increase sequentially. In one optional embodiment, the first preset percentage is 5%, the second preset percentage is 10%, and the third preset percentage is 15%.

[0058] Step 1063: Determine the deviation level based on the structural deviation of the operation and maintenance phase.

[0059] Specifically, if the structural deviation of the operation and maintenance phase is less than or equal to the fourth preset percentage, the deviation is determined to be low; if the structural deviation of the operation and maintenance phase is greater than the fourth preset percentage and less than or equal to the fifth preset percentage, the deviation is determined to be relatively low; if the structural deviation of the operation and maintenance phase is greater than the fifth preset percentage and less than or equal to the sixth preset percentage, the deviation is determined to be moderate; and if the structural deviation of the operation and maintenance phase is greater than the sixth preset percentage, the deviation is determined to be relatively high.

[0060] The fourth preset percentage, the fifth preset percentage, and the sixth preset percentage increase sequentially. In one optional embodiment, the fourth preset percentage is 5%, the fifth preset percentage is 10%, and the sixth preset percentage is 15%.

[0061] Step 1064: Obtain the carbon footprint evaluation level based on the carbon emission intensity level, the ecological disturbance level, and the deviation level.

[0062] As described above, a carbon footprint evaluation level is obtained based on the carbon emission intensity level, ecological disturbance level, and deviation level. A low-carbon performance evaluation index system for hydropower stations is constructed, which can achieve accurate quantitative evaluation of the low-carbon attributes of hydropower projects.

[0063] In an alternative implementation, after step 1063, the method further includes: Carbon reduction measures are generated based on the carbon footprint assessment level.

[0064] Specifically, if carbon emission intensity is high, the main carbon emission sources throughout the life cycle should be identified and improved, with a focus on ecological disturbances before construction and long-term cumulative emissions during the operation phase. If ecological disturbances are significant, priority should be given to improving the scope of vegetation clearing, timber resource utilization pathways, incineration ratio control, and post-construction ecological restoration and carbon sink compensation measures. If the deviation is high, it should be classified as whether the proportion of emissions during the operation phase is too large or too small. If it is too small, it is necessary to monitor whether carbon emissions in other phases are too large. If it is too large, it is necessary to strengthen greenhouse gas monitoring and water level management in the reservoir area, reduce wear and tear on key equipment, and prevent sulfur hexafluoride leakage.

[0065] This invention adopts a five-stage division method: "vegetation clearing - raw material and equipment acquisition - hydropower station construction - operation and maintenance - decommissioning and recycling." The boundaries between the two stages are not entirely consistent. In particular, the vegetation clearing stage in this invention not only includes emissions from mechanical operations and differentiated vegetation disposal, but also further incorporates carbon sink losses caused by permanent inundation areas and temporary construction land occupation. Therefore, its evaluation meaning is significantly broader than that of the conventional pre-construction stage in existing technologies.

[0066] To verify the effectiveness of the method described above, a hydropower station in Fujian Province with an installed capacity of 1.61 million kilowatts was used as a case study to conduct a detailed analysis of the carbon footprint of hydropower generation throughout its entire life cycle. The lifespan of the power station was set at 150 years, and two accounting schemes were constructed for comparison: Scheme 1 is the traditional scheme, whose accounting boundary does not include the vegetation clearing stage; Scheme 2 is the scheme proposed in this invention, which includes the vegetation clearing stage in the accounting scope.

[0067] The vegetation clearing phase primarily considers the energy consumption of construction machinery and equipment, the carbon emissions corresponding to different vegetation treatment methods, and the carbon sinks of the corresponding vegetation. Regarding the accounting boundaries, the following two points need clarification: First, the portion transported out and used as timber is not directly counted as zero during clearing, but is considered to have entered the wood product carbon pool, and its delayed carbon emissions are calculated according to the first-order decay model in the wood product lifecycle; Second, the greenhouse gases released by the vegetation submerged underwater in the reservoir during decomposition in the anaerobic environment have already been included in the reservoir greenhouse gas emission accounting scope during the hydropower station operation phase, and are not included in this phase to avoid double counting. Specific data are shown in Tables 1, 2, and 3.

[0068] Table 1 Energy consumption and carbon emission factors of vegetation clearing

[0069] Table 2. Different vegetation treatments and corresponding treatment amounts

[0070] Table 3. Carbon sequestration capacity and land area data of different vegetation types

[0071] Based on the above data, the carbon emissions for this stage can be calculated to be 2,896,808.60 tons. The parameters for this stage were obtained as follows: diesel and gasoline consumption were obtained from ledger records; vegetation cover area, permanently submerged area, and temporary land occupation area were obtained by overlaying the reservoir inundation line with the land use status map, and verified through on-site boundary surveys; biomass density was determined by vegetation type, using forest / farmland survey results for the project area and verified against literature on vegetation of the same climate and type; vegetation carbon content was determined using measured sample analysis values ​​from literature on this project, and verified against the corresponding recognized coefficients for vegetation types; timber volume, burning volume, and submerged volume were obtained from transport documents and verified against disposal destination records; the decay constant was determined based on the type of wood products and expected service life; carbon sequestration per unit area was selected from regional ecological monitoring data and verified against literature on vegetation of the same climate and type.

[0072] In the raw material and equipment acquisition stage, the main large equipment of the hydropower station are turbines, generators and transformers. Their types, quantities and emission factors are shown in Table 4.

[0073] Table 4 Carbon Emission Data List for the Raw Material and Equipment Acquisition Phase

[0074] Based on the above data, the carbon emissions for this stage can be calculated to be 83,076 tons. The parameters for this stage were obtained as follows: the equipment model and quantity were determined from the completed equipment ledger; the equipment emission factors were obtained from the life cycle assessment data and corporate carbon accounting reports provided by the equipment manufacturers.

[0075] During the construction phase of a hydropower station, the main construction materials considered in the construction of the hydropower station are cement, C30 concrete, steel bars and metal structures (gates, etc.), and their quantities and emission factors are shown in Table 5.

[0076] Table 5 Carbon Emission Data List During the Construction Phase

[0077] Based on the above data, the carbon emissions for this stage can be calculated to be 1,859,410 tons. The parameters for this stage were obtained as follows: the quantities of various building materials were determined from the completed project ledger; the carbon emission factors of materials were determined using the CPCD database (China Important Conference Papers Full-text Database).

[0078] During the operation and maintenance phase, equipment replacement, equipment energy consumption, and ecological greenhouse gas emissions from the reservoir are considered. The equipment lifespan is set at 25 years, with six replacements over 150 years. Ecological greenhouse gas emissions are not fixed throughout the entire lifespan; the emissions first increase and then decrease. This example takes the average value, and the various data are shown in Table 6.

[0079] Table 6 Carbon Emission Data List for Operation and Maintenance Phase

[0080] Considering the energy consumption of the transformer during operation, the carbon emissions of this key electrical equipment are calculated to be 1,356,286.15 tons based on the formula and its parameters. From the above data, the total carbon emissions for this stage are 12,703,089.41 tons. The parameters for this stage were obtained as follows: equipment replacement volume was determined by the ratio of the individual equipment's lifespan to the hydropower station's lifespan; plant power consumption and sulfur hexafluoride consumption were determined from the hydropower plant's records; and annual greenhouse gas emissions from the reservoir were determined from relevant literature on the hydropower station.

[0081] The transportation sub-process during the construction phase considers the transportation of different materials and equipment from the manufacturer to the hydropower station. The weight, transportation distance, and emission factors of different types of materials and equipment are shown in Table 7.

[0082] Table 7. Carbon Emission Data List for Transportation Processes

[0083] Based on the above data, the carbon emissions for this stage can be calculated to be 10,934 tons. The parameters for this stage were obtained as follows: the transport weight was determined by the procurement list; since the actual route could not be obtained, the transport mileage was determined by the shortest feasible transport route from the manufacturing location to the project location; and the transport emissions were determined by the type of transport vehicle and the CPCD database.

[0084] Referring to research findings on the decommissioning of similar large-scale hydropower projects, the carbon emissions in the decommissioning and recycling phase account for approximately 8.95% of the total carbon emissions in the original four phases. Therefore, the carbon emissions in this phase can be calculated to be 1,440,700.27 tons.

[0085] Based on the above data, the carbon emissions of the hydropower station at all stages can be calculated, and the results are shown in Table 8.

[0086] Table 8 Carbon Emissions and Total Carbon Emissions at Different Stages

[0087] Table 9 Carbon footprint factors for different schemes

[0088] Different schemes for the carbon footprint of hydropower stations throughout their entire life cycle, for example Figure 3 As shown in Table 9, by comparing Scheme 1 and Scheme 2, it can be clearly seen that Scheme 2 has a more comprehensive accounting boundary and a higher degree of engineering fit in calculating the carbon footprint of hydropower.

[0089] Option 1 follows traditional accounting practices, with its system boundary typically covering stages such as material and equipment acquisition, construction, operation and maintenance, and decommissioning. However, it does not take into account vegetation clearing activities during the initial construction phase of the hydropower station. Yet, vegetation clearing directly disrupts the biomass carbon pool and causes the loss of carbon sink functions, representing a substantial source of carbon emissions and a significant point of change in carbon sinks throughout the project's lifecycle. Option 2, building upon this traditional framework, incorporates equipment energy consumption carbon emissions generated during the vegetation clearing phase and net carbon emissions resulting from differentiated vegetation treatment into the accounting, thus achieving a full-chain carbon emission analysis of the hydropower project from site preparation to final decommissioning. This boundary expansion makes the accounting results more comprehensive. The carbon footprint factor calculated by Option 2 (22.25 gCO2e / kWh) is approximately 17.97% higher than that of Option 1 (18.86 gCO2e / kWh). This quantitative difference reveals the environmental impact that traditional methods may have underestimated. More importantly, the accounting framework of Scheme 2 is more in line with engineering realities. It fully depicts the actual physical process of "vegetation destruction - carbon release / transfer - carbon sink loss," filling the accounting gap in traditional assessments regarding the conversion from "natural carbon pools" to "artificial facilities." Therefore, Scheme 2 not only improves the accuracy of carbon footprint accounting but also provides a more solid scientific basis for low-carbon planning, ecological impact assessment of hydropower projects, and the industry's achievement of "dual carbon" goals.

[0090] Table 10 Comparison of the present invention with the national carbon footprint factor

[0091] As shown in Table 10, the hydropower carbon footprint factor calculated by this invention is higher than the relevant national standards or commonly used benchmark values. This difference is mainly due to the combined effect of the following two key factors: First, regarding reservoir discharge during the operational phase, Fujian Province, where this invention's example is located, is situated in a subtropical monsoon climate zone with consistently high water temperatures throughout the year. This natural condition significantly enhances the activity of microorganisms in reservoir sediments and submerged organic matter, thereby accelerating anaerobic decomposition processes. Consequently, over the lifecycle of the power station, the generation and emission flux of greenhouse gases such as methane per unit of power generation are higher than typical levels in temperate climate regions. Therefore, even under the same accounting boundary, climate-driven microbial processes cause a regional increase in the carbon footprint factor in this case. Second, regarding the expansion of the accounting boundary, the proposed solution explicitly includes the vegetation clearing phase in the accounting scope, encompassing the direct energy consumption carbon emissions, vegetation carbon storage losses, and indirect carbon emissions caused by the loss of vegetation carbon sink functions. This carbon leakage is often overlooked in traditional carbon footprint accounting frameworks. Therefore, the inclusion of the "vegetation clearing phase" systematically supplements the key carbon costs in the transformation process from natural ecosystems to artificial water conservancy facilities, which is the core methodological reason for the more comprehensive accounting results and correspondingly increased numerical values ​​in this invention.

[0092] like Figure 4 As shown, the life cycle assessment results indicate that the operation and maintenance phase is the primary source of carbon footprint for hydropower systems throughout their entire life cycle, accounting for as much as 66.9% of carbon emissions. Carbon emissions during this phase exhibit a multi-source coexistence characteristic: on the one hand, the residual organic matter at the bottom of the reservoir's inundation zone continues to degrade in a long-term anaerobic environment, releasing methane, carbon dioxide, and nitrogen dioxide fluxes. Although these fluxes decrease with the years of operation, their cumulative effect over the entire life cycle is extremely significant. On the other hand, the continuous no-load and load power losses of key electrical equipment (such as the main step-up transformer) during its decades-long service life cannot be ignored, as well as the trace leaks and replenishment of high GWP (Global Warming Potential) gases such as sulfur hexafluoride during the operation and maintenance of equipment like GIS (Geographic Information System).

[0093] The vegetation clearing phase accounts for 15.3% of the carbon footprint, and the accounting for this part profoundly reveals the dramatic changes in ecological carbon emissions caused by land use change. Its carbon footprint boundary not only covers the direct fuel consumption of large-scale machinery operations and the carbon emissions from waste biomass (incineration or landfill), but more importantly, the core indirect carbon cost stems from the deprivation of native vegetation's carbon sequestration capacity (i.e., carbon sinks) by permanent reservoir inundation areas and temporary construction land occupation. Furthermore, the vegetation biomass transported out for use as wood products during this phase does not cross the accounting boundary, but rather follows a first-order decay model, slowly and delayed as a carbon pool over its long life cycle.

[0094] Furthermore, the construction and decommissioning / recycling phases of hydropower stations account for 9.8% and 7.6% of the total carbon footprint, respectively. Carbon emissions during the construction phase primarily focus on the production and transportation of building materials such as cement and steel. In contrast, the core carbon emissions during the decommissioning / recycling phase, besides the mechanical energy consumption and logistics of dismantling large structures, lie in the differentiated disposal of waste—that is, distinguishing between the equivalent carbon absorption benefits of recyclable materials and the direct emissions from non-recyclable waste (landfill / incineration). Comparatively, the acquisition of raw materials and equipment (upstream industrial manufacturing) contributes relatively little to the overall system's carbon footprint.

[0095] Based on the above calculation results, and further combined with the constructed evaluation index system, the low-carbon performance of the hydropower station of this invention is quantitatively evaluated. The evaluation no longer uses a single total score approach, but rather a joint judgment from three dimensions: overall emission level, intensity of ecological disturbance before construction, and structural rationality during the operation phase. Specifically, this case is analyzed using three indicators: carbon footprint factor per unit of power generation, the proportion of carbon emissions from vegetation ecological disturbance, and the degree of structural deviation during the operation and maintenance phase. First, from the perspective of overall emission level, the carbon footprint factor of this invention is 22.25 gCO2e / kWh, higher than the national carbon footprint factor of 14.10 gCO2e / kWh, indicating that after adopting a more complete life cycle boundary, the carbon emission intensity per unit of power generation of the hydropower station of this invention is at a medium level. This shows that although this invention possesses the clean energy attributes of hydropower, its low-carbon performance is not optimal, but rather is strongly influenced by ecological disturbance before construction and long-term cumulative emissions during the operation phase, leading to increased carbon emissions.

[0096] Secondly, regarding the intensity of pre-construction ecological disturbance, the carbon footprint of the vegetation clearing stage in this invention's example accounts for 15.3%. Since the vegetation clearing stage in this invention not only includes direct emissions from mechanical equipment operations and emissions from differentiated vegetation disposal, but also carbon sink losses caused by permanent inundation areas and temporary construction land occupation, this indicator essentially reflects the burden of pre-construction ecological disturbance on the total carbon footprint, rather than the proportion of a typical stage. This high indicator indicates that pre-construction ecosystem disturbance is one of the important factors driving up the full life-cycle carbon footprint in this case, and is also a key source of carbon cost that this invention can additionally identify compared to traditional accounting boundaries.

[0097] Furthermore, from the perspective of the structural rationality of the operation phase, the carbon emission ratio during the operation and maintenance phase in this invention's example is 66.9%. The average proportion of the operation and maintenance phase in 24 existing large and medium-sized hydropower projects in the upper reaches of the Yangtze River is 67.20%, indicating that the operation and maintenance phase being the dominant phase in the life cycle is a common structural characteristic of hydropower projects. Therefore, the deviation of the operation and maintenance phase structure in this invention is: I op =66.9% 67.2% | = 0.3%, indicating that the proportion of the operational phase in this invention's case is basically consistent with the typical structure of similar hydropower projects. In other words, although the operational phase in this invention's case is still the dominant phase of the entire life cycle carbon footprint, this is a common life cycle structure of hydropower projects and does not constitute an abnormal deviation.

[0098] Based on the above three indicators, it can be concluded that the overall carbon emission intensity is moderate, the pre-construction ecological disturbance is relatively strong, and the structure during the operation phase is basically consistent with the typical distribution of similar hydropower projects. Therefore, subsequent carbon reduction measures in this invention case should prioritize controlling pre-construction ecological disturbance, including improving the scope of vegetation clearing, improving differentiated vegetation treatment methods, and strengthening ecological restoration and carbon sink compensation measures. On this basis, further refined emission reduction should be carried out focusing on controlling reservoir ecological greenhouse gas emissions, reducing losses of key electrical equipment, and managing high GWP gas leaks during the operation phase. As can be seen from the above analysis, this invention can not only achieve full life-cycle carbon footprint calculation, but also quantitatively interpret the low-carbon nature of the project based on key indicators, and further identify subsequent emission reduction priorities.

[0099] Please refer to Figure 5 The present invention also provides a hydropower generation life cycle carbon footprint assessment system 400, including a memory 401, a processor 402, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the various steps of the hydropower generation life cycle carbon footprint assessment method as described above.

[0100] In summary, the above-mentioned method and system for assessing the carbon footprint of hydropower throughout its entire life cycle, as described in this invention, calculates the carbon emissions during the vegetation clearing stage based on the carbon emissions generated by the energy consumed by construction machinery and equipment used during site clearing and logging, the carbon emissions generated by different vegetation disposal methods after vegetation clearing, and the dynamic loss of ecological carbon sequestration capacity. It then obtains the total carbon emissions throughout the entire life cycle of hydropower generation based on the carbon emissions during the vegetation clearing stage, the raw material and equipment acquisition stage, the hydropower station construction stage, the operation and maintenance stage, and the decommissioning and recycling stage. Based on the total carbon emissions, it calculates the carbon footprint factor per unit of electricity generated. It calculates the proportion of carbon emissions from vegetation ecological disturbance based on the total carbon emissions and the carbon emissions during the vegetation clearing stage. It calculates the structural deviation degree of the operation and maintenance stage based on the total carbon emissions and the carbon emissions during the operation and maintenance stage. Finally, it determines the carbon footprint assessment level based on the carbon footprint factor per unit of electricity generated, the proportion of carbon emissions from vegetation ecological disturbance, and the structural deviation degree of the operation and maintenance stage. Thus, when calculating the total carbon emissions, it comprehensively considers the direct energy consumption during the vegetation clearing operation. The study analyzes the differentiated carbon emissions from biomass disposal following consumption and vegetation clearing, as well as the ecological carbon sink losses caused by vegetation clearing. This approach more accurately reflects the actual engineering situation and measures the net carbon emissions during the vegetation clearing phase of hydropower generation throughout its entire life cycle, as well as its impact on the cumulative carbon footprint. Furthermore, it establishes three core evaluation indicators based on three dimensions: overall emission level, pre-construction ecological disturbance intensity, and structural rationality during operation. These indicators include the carbon footprint factor per unit of power generation, the proportion of carbon emissions from vegetation ecological disturbance, and the structural deviation during operation and maintenance. This allows for a quantitative interpretation of the project's low-carbon characteristics without relying on a single overall score, thus achieving more precise carbon footprint accounting and evaluation. The vegetation clearing phase not only considers the direct energy consumption of the operation process but also profoundly reveals the indirect carbon emissions caused by land use change. This compensates for the traditional model's neglect of the impact of vegetation status on carbon emission accounting, resulting in more comprehensive and accurate calculations. It achieves a panoramic quantification of the carbon footprint throughout the entire life cycle, from initial vegetation destruction to the final decommissioning of the power station, and is more closely aligned with actual physical processes.

[0101] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent modifications made based on the content of the present invention specification and drawings, or direct or indirect applications in related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A method for evaluating the carbon footprint of hydropower throughout its entire life cycle, characterized in that, include: Carbon emissions during the vegetation clearing phase are calculated based on the carbon emissions generated by the energy consumed by construction machinery and equipment used in the site clearing and logging process, the carbon emissions generated by different vegetation disposal methods after vegetation clearing, and the dynamic loss of ecological carbon sequestration capacity. The total carbon emissions of hydropower generation throughout its entire life cycle are obtained from the carbon emissions during the vegetation clearing phase, the raw material and equipment acquisition phase, the hydropower station construction phase, the operation and maintenance phase, and the decommissioning and recycling phase. Calculate the carbon footprint factor per unit of electricity generated based on the total carbon emissions; The proportion of carbon emissions from vegetation ecological disturbance is calculated based on the total carbon emissions and the carbon emissions from the vegetation clearing phase. The structural deviation of the operation and maintenance phase is calculated based on the total carbon emissions and the carbon emissions of the operation and maintenance phase. The carbon footprint evaluation level is determined based on the carbon footprint factor per unit of electricity generation, the proportion of carbon emissions from vegetation ecological disturbance, and the structural deviation of the operation and maintenance phase.

2. The method according to claim 1, characterized in that, Before calculating carbon emissions during the vegetation clearing phase based on carbon emissions from energy consumption of construction machinery and equipment used in site clearing and logging, carbon emissions from different vegetation disposal methods after vegetation clearing, and dynamic losses of ecological carbon sequestration capacity, the calculation also includes: Obtain the energy quality and corresponding carbon emission factors of the construction machinery and equipment used in the vegetation clearing phase; Calculate the carbon emissions generated by the energy consumed by construction machinery and equipment used in the site clearing and logging processes based on the energy quality and the carbon emission factor. Calculate carbon emissions from combustion and carbon emissions from wood utilization; Calculate the carbon emissions generated by different vegetation disposal methods after vegetation clearing based on the carbon emissions from combustion and the carbon emissions from timber utilization. To obtain the vegetation area submerged by the reservoir, the carbon sequestration capacity of vegetation per unit area per unit time, the life cycle of the hydropower station, the area of ​​vegetation occupied by temporary construction land, and the recovery delay time required after the temporary land occupation ends. The dynamic loss of ecological carbon sequestration capacity is calculated based on the vegetation area submerged by the reservoir, the carbon sequestration capacity of the vegetation per unit area per unit time, the life cycle of the hydropower station, the vegetation area occupied by the temporary construction site, and the recovery delay time required after the temporary site is completed.

3. The method according to claim 2, characterized in that, The calculation of carbon emissions from combustion and carbon emissions from wood use includes: To obtain vegetation biomass and vegetation carbon content; The carbon emissions from combustion and carbon emissions from timber utilization are calculated based on the vegetation biomass and the vegetation carbon content.

4. The method according to claim 2, characterized in that, The carbon emissions generated by the energy consumed by construction machinery and equipment used in site clearing and logging are calculated based on the energy quality and carbon emission factors, specifically as follows: ； In the formula, This refers to the carbon emissions generated by the energy consumed by construction machinery and equipment used in site clearing and logging processes. This indicates the number of different types of energy consumed by construction machinery and equipment used during the vegetation clearing phase. This indicates the consumption of construction machinery and equipment during the vegetation clearing phase. i Energy quality, This indicates the consumption of construction machinery and equipment during the vegetation clearing phase. i Carbon emission factors of various energy sources; The carbon emissions generated by different vegetation disposal methods after vegetation clearing are calculated based on the carbon emissions from combustion and the carbon emissions from timber utilization. Specifically: ； In the formula, This indicates the carbon emissions generated by different vegetation disposal methods after vegetation clearing. Indicates carbon emissions from combustion. Indicates the carbon emissions from timber utilization; The dynamic loss of ecological carbon sequestration capacity is calculated based on the vegetation area submerged by the reservoir, the carbon sequestration capacity of vegetation per unit area per unit time, the lifespan of the hydropower station, the area of ​​vegetation occupied by the temporary construction site, and the recovery delay time required after the temporary site is completed. Specifically: ； In the formula, This represents the dynamic loss of ecological carbon sequestration capacity. This indicates the number of vegetation species submerged by the reservoir. Indicates the first flood of the reservoir i Area of ​​vegetation type Represents the unit area per unit time. i Carbon sequestration capacity of vegetation Indicates the lifespan of a hydropower station. This indicates the number of vegetation types occupied by the temporary construction site. Indicates the area occupied by temporary construction land. i Area of ​​vegetation-like vegetation This indicates the recovery delay required after the temporary occupation ends.

5. The method according to claim 1, characterized in that, The carbon footprint factor per unit of electricity generation, calculated based on the total carbon emissions, includes: Obtain the total power generation of hydropower throughout its entire life cycle; The carbon footprint factor per unit of electricity generated is calculated based on the total electricity generation over the entire life cycle of the hydropower project and the total carbon emissions. Specifically: ； In the formula, This represents the carbon footprint factor per unit of electricity generated. This represents the total carbon emissions over the entire life cycle of hydropower generation. This represents the total power generation of hydropower throughout its entire life cycle.

6. The method according to claim 5, characterized in that, The proportion of carbon emissions from vegetation ecological disturbance is calculated based on the total carbon emissions and the carbon emissions from the vegetation clearing phase, specifically as follows: ； In the formula, This indicates the proportion of carbon emissions caused by vegetation ecological disturbance. This indicates carbon emissions during the vegetation clearing phase.

7. The method according to claim 5, characterized in that, The structural deviation of the operation and maintenance phase is calculated based on the total carbon emissions and the carbon emissions during the operation and maintenance phase, specifically as follows: ； In the formula, This indicates the degree of structural deviation during the operation and maintenance phase. This indicates carbon emissions during the operation and maintenance phase. This represents the average value for the operation and maintenance phase of similar hydropower projects.

8. The method according to claim 1, characterized in that, The carbon footprint assessment level is determined based on the carbon footprint factor per unit of electricity generation, the proportion of carbon emissions from vegetation ecological disturbance, and the structural deviation during the operation and maintenance phase, including: The carbon emission intensity level is determined based on the carbon footprint factor per unit of electricity generated. The ecological disturbance level is determined based on the proportion of carbon emissions from the vegetation ecological disturbance. The deviation level is determined based on the structural deviation during the operation and maintenance phase. The carbon footprint assessment level is obtained based on the carbon emission intensity level, the ecological disturbance level, and the deviation level.

9. The method according to claim 1, characterized in that, Before calculating the total carbon emissions for the entire lifecycle of hydropower generation based on the carbon emissions from the vegetation clearing phase, the raw material and equipment acquisition phase, the hydropower station construction phase, the operation and maintenance phase, and the decommissioning and recycling phase, the following is also included: The carbon emissions during the raw material and equipment acquisition phase are calculated based on the required quantity of raw materials and equipment acquired during the raw material and equipment acquisition phase and their corresponding carbon emission factors. Carbon emissions during the construction phase of a hydropower station are calculated based on carbon emissions generated during construction and transportation. Carbon emissions during the operation and maintenance phase are calculated based on carbon emissions from energy and material consumption, carbon emissions from energy consumption and replacement of critical electrical equipment during operation, and greenhouse gas emissions from reservoirs. Carbon emissions during the decommissioning and recycling phase are calculated based on carbon emissions generated during dismantling, transportation, and waste disposal.

10. A hydropower generation life-cycle carbon footprint assessment system, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements each step of the method for evaluating the carbon footprint of hydropower generation throughout its entire life cycle as described in any one of claims 1 to 9.

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