A method for evaluating water energy resources based on GIS technology considering ecological constraints

Abstract

The present application belongs to the field of water resources and water environment, in particular to a water energy resource assessment method based on GIS technology considering ecological constraints, comprising five steps of data preparation, calculation of theoretical reserves of water energy resources, assessment of theoretical reserves under ecological flow constraints, assessment of theoretical reserves under ecological protection area constraints, and comprehensive consideration of ecological constraints in the assessment of theoretical reserves, the method uses high-precision topographic data to extract digital river network and obtain hydrological data of the river; the point of inclination is taken as the control point to divide the control river section, and the factors such as river slope, flow and drop are analyzed to calculate the theoretical reserves of the river; considering the ecological flow constraints in dry season and wet season, and the spatial constraints of ecological protection area, the theoretical reserves are re-evaluated, and the water energy resource assessment method fully considers the ecological constraints such as prohibition of development in ecological red line area, ecological flow discharge of diversion type power station and withdrawal of part of the power station, and makes accurate assessment on the theoretical reserves of water energy resources.

Description

Technical Field

[0001] This invention belongs to the field of water resources and water environment, and in particular relates to a method for assessing hydropower resources based on GIS technology and considering ecological constraints. Background Technology

[0002] Hydropower resource assessment is a fundamental task for hydropower development and river basin planning, and is of great significance for the rational utilization of hydropower resources and the promotion of sustainable development. Traditional hydropower resource assessment mainly relies on surveys, field visits, and on-site surveys to obtain hydrological data and topographic maps for calculation and analysis. This method is not only labor-intensive and costly, but also has limited accuracy, making it difficult to meet the needs of modern hydropower development.

[0003] In recent years, with the development of information technology, new technologies such as big data, the Internet of Things, cloud computing, and geographic information systems have increasingly become driving forces for innovation in water conservancy. Remote sensing and geographic information systems (GIS) are also gradually being applied to water energy resource surveys and assessments. However, existing assessment methods still have some shortcomings: on the one hand, they do not adequately consider ecological constraints and lack specific and operable ecological constraint indicators; on the other hand, the assessment process is cumbersome, time-consuming, and inefficient.

[0004] The current standard, "Guidelines for Hydropower Resource Survey and Evaluation" (SL562-2011), provides hydropower resource evaluation indicators that give insufficient consideration to factors such as ecological constraints, which is detrimental to the coordinated development of rational utilization of hydropower resources and ecological protection in the new era. Hydropower resource surveys and evaluations need to consider factors such as the core areas of nature reserves, buffer zones, prohibited development areas within ecological red lines, ecological flow release from diversion power stations, comprehensive water resource utilization, and the closure of some power stations.

[0005] Therefore, developing a hydropower resource assessment method that combines GIS technology with full consideration of ecological constraints is of great significance for scientifically assessing hydropower resources and promoting their sustainable development. Summary of the Invention

[0006] The purpose of this invention is to provide a hydropower resource assessment method based on GIS technology that takes into account ecological constraints, aiming to properly handle the relationship between hydropower resource development and river ecological protection, and to achieve the coordinated unity of hydropower resource development and ecological environmental protection.

[0007] This invention proposes a method for assessing hydropower resources based on GIS technology and considering ecological constraints, comprising: The data preparation steps include acquiring a digital elevation model, hydropower station coordinates, nature reserve boundaries, and multi-year average runoff depth data; based on the digital elevation model, extracting hydrological data on the river network, flow rate, flow direction, discharge point, catchment area, and catchment area; and calculating the multi-year average runoff depth and flow rate of the catchment area based on the catchment area and multi-year average runoff depth data. Ecological constraints mainly consider two aspects: first, the development of river hydropower resources may involve some environmentally sensitive factors, mainly referring to prohibited development areas such as the core protected areas of national parks and core protected areas of nature reserves, referred to as ecological protection zone constraints; second, the ecological flow discharge to ensure the ecological water demand of downstream river channels, referred to as ecological flow constraints. The steps for calculating the theoretical hydropower resource potential are as follows: The river is divided into multiple control sections using the discharge point as a control point; the elevation difference between adjacent control points is calculated; based on the elevation difference and the multi-year average flow of the catchment area, the theoretical hydropower resource potential of each control section is calculated; the theoretical hydropower resource potential of each control section is summed to obtain the total theoretical hydropower resource potential of the river; wherein, the theoretical hydropower resource potential of the river is accumulated segment by segment from the source to the estuary. The steps for assessing the theoretical potential of hydropower resources under ecological flow constraints are as follows: calculate the average annual ecological flow; and calculate the theoretical potential of hydropower resources considering ecological flow constraints based on the multi-year average flow of the controlled river section, the average annual ecological flow, and the elevation difference of the control point. The steps for assessing the theoretical potential of hydropower resources under the constraints of ecological protection zones include: determining whether the control point is located within the ecological protection prohibited development zone; and calculating the theoretical potential of hydropower resources considering the constraints of ecological protection zones based on the total theoretical potential of the river's hydropower resources and the theoretical potential of the hydropower resources of the control river section located within the ecological protection prohibited development zone. The theoretical hydropower resource potential assessment steps taking into account ecological constraints are as follows: based on the theoretical hydropower resource potential considering ecological flow constraints and the theoretical hydropower resource potential considering ecological flow constraints in the controlled river section located in the ecological protection prohibited development zone, the theoretical hydropower resource potential considering ecological flow constraints is calculated.

[0008] Preferably, the calculation of the multi-year average runoff depth of the catchment area includes: Obtain the multi-year average runoff depth and area of ​​each grid within the catchment area; The multi-year average runoff depth of the catchment area is calculated by weighted averaging based on the multi-year average runoff depth and area of ​​each grid within the catchment area.

[0009] Preferably, the calculation of the multi-year average flow rate of the catchment area includes: Obtain the catchment area and the average annual runoff depth of the catchment area; The average annual flow rate of the catchment area is calculated based on the catchment area, the average annual runoff depth of the catchment area, and the time conversion factor.

[0010] Preferably, the calculation of the elevation difference between adjacent control points includes: Obtain the elevation values ​​of adjacent control points; Calculate the difference in elevation between adjacent control points to obtain the elevation difference between the control points at both ends of the controlled river section.

[0011] Preferably, the calculation of the theoretical hydropower potential of the controlled river section includes: Obtain the multi-year average flow of the controlled river section and the elevation difference between the control points at both ends of the controlled river section; Based on the gravitational acceleration constant, the multi-year average flow of the controlled river section, and the elevation difference between the two ends of the controlled river section, the theoretical hydropower potential of the controlled river section is calculated.

[0012] Preferably, the calculation of the theoretical total potential of the river hydropower resources includes: To obtain the theoretical hydropower potential of each controlled river section; The theoretical hydropower potential of each controlled river section is summed to obtain the total theoretical hydropower potential of the river.

[0013] Preferably, the calculation of the average annual ecological flow includes: The year is divided into a dry season and a wet season. Obtain the ecological flow during the dry season and the ecological flow during the wet season of the controlled river section; Based on the ecological flow during the dry season, the ecological flow during the wet season, and their respective time proportions throughout the year, the average annual ecological flow of the controlled river section is calculated.

[0014] Preferably, the calculation of the theoretical potential of hydropower resources considering ecological flow constraints includes: Obtain the multi-year average flow, annual average ecological flow, and elevation difference between the two ends of the control point in each control section; Based on the gravitational acceleration constant, the difference between the multi-year average flow and the annual average ecological flow of the controlled river section, and the elevation difference between the control points at both ends of the controlled river section, the theoretical hydropower potential of each controlled river section considering ecological flow constraints is calculated. The theoretical hydropower resource potential considering ecological flow constraints in each controlled river section is summed to obtain the theoretical hydropower resource potential considering ecological flow constraints.

[0015] Preferably, the calculation of the theoretical hydropower resource potential considering the constraints of ecological protection zones includes: Use GIS spatial connection tools to determine whether control points are located within ecological protection prohibited development zones; To obtain the theoretical hydropower potential of the controlled river sections located within ecological protection and prohibited development zones; The theoretical hydropower potential of the river is calculated by subtracting the theoretical hydropower potential of the controlled river section located within the ecological protection and prohibited development zone from the total theoretical potential of the river's hydropower resources. This calculation takes into account the constraints of the ecological protection zone.

[0016] Preferably, the calculation of the theoretical potential of hydropower resources taking into account ecological constraints includes: To obtain the theoretical potential of hydropower resources considering ecological flow constraints; To obtain the theoretical hydropower potential of the controlled river section located within the ecological protection and prohibited development zone, taking into account ecological flow constraints; The theoretical hydropower resource reserve considering ecological constraints is calculated by subtracting the theoretical hydropower resource reserve considering ecological flow constraints from the theoretical hydropower resource reserve considering ecological flow constraints in the controlled river section located in the ecological protection prohibited development zone.

[0017] The beneficial effects of this invention include: By introducing ArcPy site packages and leveraging their powerful geographic data processing capabilities, the process of assessing hydropower resources has been automated and batch-processed, significantly improving the speed and accuracy of data processing and solving the problems of complex and time-consuming traditional assessment methods.

[0018] A comprehensive assessment system consisting of two levels—ecological flow constraints and ecological protection zone constraints—was established, which fully considered ecological constraints such as the prohibition of development in ecological red line areas, the release of ecological flow from diversion power stations, and the withdrawal of some power stations, thus achieving a balance between hydropower resource development and ecological protection.

[0019] A refined control river segment division method based on the discharge point is proposed. Each control river segment corresponds to a catchment area, which more accurately reflects the hydropower characteristics of each section of the river and improves the assessment accuracy.

[0020] By taking into account seasonal differences in ecological flow, the year is divided into dry and wet seasons, and the ecological flow demand is calculated separately, which is more in line with the actual needs of ecological protection.

[0021] The system integrates multi-source data, including DEM data, hydropower station coordinates, nature reserve boundaries, and multi-year average runoff depth, forming a unified data foundation and improving the comprehensiveness and accuracy of the assessment.

[0022] It provides technical support for regional river hydropower development planning, enables accurate assessment of the theoretical reserves of hydropower resources, and provides an important reference for Chinese hydropower enterprises to explore international markets. Attached Figure Description

[0023] Figure 1This is a schematic diagram of the overall process of a hydropower resource assessment method based on GIS technology and considering ecological constraints according to the present invention. Figure 2 This is a detailed flowchart illustrating the data preparation steps in this invention; Figure 3 This is a detailed flowchart illustrating the steps for calculating the theoretical reserves of hydropower resources in this invention. Figure 4 This is a detailed flowchart illustrating the ecological flow constraint assessment steps in this invention. Figure 5 This is a detailed flowchart illustrating the ecological protection zone constraint assessment steps in this invention. Figure 6 This is a detailed flowchart illustrating the comprehensive ecological constraint assessment steps in this invention. Figure 7 A comparison chart showing constraints on hydropower potential; Figure 8 Map showing site traffic and protected area distribution; Figure 9 This is a comparison chart of installed capacity and hydropower reserves. Detailed Implementation

[0024] Please refer to Figure 1 - Figure 9 The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0025] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0026] In one embodiment of the present invention, a method for assessing hydropower resources based on GIS technology and considering ecological constraints includes a data preparation step, a calculation step for the theoretical potential of hydropower resources, an assessment step for the theoretical potential of hydropower resources under ecological flow constraints, an assessment step for the theoretical potential of hydropower resources under ecological protection zone constraints, and an assessment step for the theoretical potential of hydropower resources that comprehensively considers ecological constraints.

[0027] like Figure 1 As shown, the overall process of the method of the present invention includes five main steps, which are progressive and related to each other, and finally form a complete evaluation system that comprehensively considers ecological constraints.

[0028] I. Data preparation steps: like Figure 2 As shown, the data preparation steps mainly include acquiring basic data, extracting hydrological data, and calculating relevant parameters of the catchment area.

[0029] First, acquire basic data such as the digital elevation model (DEM), hydropower station coordinates, nature reserve boundaries, and multi-year average runoff depth data. The DEM can be obtained from the geospatial data cloud (http: / / www.gscloud.cn), with a preferred resolution of 30 meters; the hydropower station coordinates and nature reserve boundaries can be obtained from relevant management departments; and the multi-year average runoff depth data can be obtained from the GRDC global runoff data (https: / / grdc.bafg.de).

[0030] Next, based on the digital elevation model (DEM), hydrological data such as river network, flow rate, flow direction, spillway, catchment area, and catchment area are extracted using hydrological tools in the ArcGIS Pro toolbox. Specifically, the DEM data is first filled to eliminate abnormal depressions and ensure flow continuity; then, the flow direction is calculated to determine the flow direction of each grid cell; next, the cumulative flow rate is calculated to obtain the catchment area of ​​each grid cell; finally, the river network is extracted based on a certain flow rate threshold (usually set to 1% of the total flow rate) and then vectorized.

[0031] For extracting the spillway point, this invention uses the spillway point capture tool in the ArcGIS Pro toolbox to capture the spillway point in the catchment area around the known coordinates of the hydropower station, with a capture distance set to 0.009 (approximately 900 meters). This distance value is the optimal value verified through multiple experiments and can accurately capture the actual location of the river spillway point. Based on the spillway point location, the catchment area tool is used to divide the corresponding catchment area and calculate its area.

[0032] Based on the extracted catchment area and multi-year average runoff depth data, the multi-year average runoff depth and multi-year average flow rate of the catchment area are calculated.

[0033] The calculation of the multi-year average runoff depth of the catchment area includes: obtaining the multi-year average runoff depth and area of ​​each grid within the catchment area; and calculating the multi-year average runoff depth of the catchment area through a weighted average based on the multi-year average runoff depth and area of ​​each grid within the catchment area. The specific calculation formula is as follows: , in: The average runoff depth of the catchment area over many years is expressed in millimeters (mm). The average runoff depth corresponding to the i-th grid in the catchment area is expressed in millimeters (mm). The area of ​​the i-th grid cell within the catchment area is expressed in square meters. ); This indicates a summation operation on all grid cells within the catchment area.

[0034] For example, suppose a catchment area contains 100 grid units, each with an area of ​​900 square meters (30 meters × 30 meters), and the average annual runoff depth of each grid unit is distributed between 500 and 1000 mm. Using the formula above, if the weighted average is 750 mm, then the average annual runoff depth of the catchment area is 750 mm.

[0035] The calculation of the multi-year average flow of a catchment area includes: obtaining the catchment area and the multi-year average runoff depth; and calculating the multi-year average flow based on the catchment area, the multi-year average runoff depth, and the time conversion factor. The specific calculation formula is as follows: , in: The average flow rate over many years in the catchment area is expressed in cubic meters per second. ); The catchment area is expressed in square kilometers. ); The average runoff depth over many years is expressed in millimeters (mm); 365.25 is the average number of days in a year, taking leap years into account; 86400 is the number of seconds in a day, expressed in seconds (s). As a unit conversion factor, Convert to .

[0036] For example, assuming a catchment area of ​​100 square kilometers and an average annual runoff depth of 750 mm, the average annual flow rate of this catchment area, calculated using the above formula, is approximately 2.38 cubic meters per second. This flow rate value is an important basic data for assessing hydropower resources.

[0037] II. Steps for calculating the theoretical reserves of hydropower resources: like Figure 3 As shown, the calculation steps for the theoretical potential of hydropower resources mainly include the division of control river sections, calculation of the elevation difference between adjacent control points, calculation of the theoretical potential of hydropower resources in the control river sections, and calculation of the total theoretical potential of hydropower resources in the river.

[0038] First, the river is divided into multiple control segments by using the spillway points as control points. Each control segment is the section between two adjacent spillway points and also corresponds to a catchment area. This method of dividing control segments based on spillway points is more precise and can accurately reflect the hydropower characteristics of each section of the river.

[0039] Next, the elevation difference between adjacent control points is calculated. This calculation includes: obtaining the elevation values ​​of adjacent control points; and calculating the difference between these elevation values ​​to obtain the elevation difference between the control points at both ends of the controlled river segment. The specific calculation formula is as follows: , in: The elevation difference between the two control points at the two ends of the i-th control segment is expressed in meters (m). Let be the elevation of the (i+1)th control point, in meters (m). Let be the elevation of the i-th control point, in meters (m). This indicates that the absolute value is taken to ensure that the elevation difference is positive.

[0040] For example, assuming the elevation of the upstream control point in a certain controlled river section is 1500 meters and the elevation of the downstream control point is 1200 meters, then the elevation difference of this controlled river section is... rice.

[0041] Next, based on the elevation difference of the control points and the multi-year average flow of the catchment area, the theoretical hydropower potential of the controlled river section is calculated. The calculation of the theoretical hydropower potential of the controlled river section includes: obtaining the multi-year average flow of the controlled river section and the elevation difference between the control points at both ends of the controlled river section; and calculating the theoretical hydropower potential of the controlled river section based on the gravitational acceleration constant, the multi-year average flow of the controlled river section, and the elevation difference between the control points at both ends of the controlled river section. The specific calculation formula is as follows: , in: represents the theoretical hydropower potential of the i-th controlled river segment, in kilowatts (kW); 9.81 is the gravitational acceleration constant, in meters per second squared (m²). ); The multi-year average flow rate of the i-th controlled river segment is expressed in cubic meters per second. ); The elevation difference between the two control points at the two ends of the i-th control segment is expressed in meters (m).

[0042] For example, continuing the example above, assuming the average annual flow rate of the controlled river section is 2.38 cubic meters per second and the elevation difference is 300 meters, then according to the formula above, the theoretical hydropower potential of this controlled river section is approximately... kilowatt.

[0043] Finally, the theoretical hydropower potential of each controlled river section is summed to obtain the total theoretical hydropower potential of the river. The calculation of the total theoretical hydropower potential of the river includes: obtaining the theoretical hydropower potential of each controlled river section; and summing the theoretical hydropower potential of each controlled river section to obtain the total theoretical hydropower potential of the river. The specific calculation formula is as follows: , in: The total potential of river hydropower resources is expressed in kilowatts (kW). The hydropower potential of the i-th controlled river section is expressed in kilowatts (kW). The total number of control points is , therefore the total number of controlled river segments is . ; This indicates a summation operation on all controlled river segments from 1 to n-1.

[0044] For example, suppose a river has 10 control points, divided into 9 control sections, with theoretical hydropower potential of 5000kW, 7000kW, 6000kW, 8000kW, 9000kW, 7500kW, 6500kW, 8500kW and 7800kW respectively. Then the total theoretical hydropower potential of the river is 5000+7000+6000+8000+9000+7500+6500+8500+7800=65300kW.

[0045] III. Steps for assessing the theoretical potential of hydropower resources under ecological flow constraints: like Figure 4 As shown, the main steps for assessing the theoretical potential of hydropower resources under ecological flow constraints include calculating the average annual ecological flow and calculating the theoretical potential of hydropower resources considering ecological flow constraints.

[0046] First, calculate the annual average ecological flow. The calculation of the annual average ecological flow includes: dividing the year into a dry season and a wet season; obtaining the ecological flow during the dry season and the ecological flow during the wet season of the controlled river section; and calculating the annual average ecological flow of the controlled river section based on the ecological flow during the dry season, the ecological flow during the wet season, and their respective time proportions in the year.

[0047] In embodiments of this invention, the year is divided into a dry season (November to March of the following year, a total of 5 months) and a wet season (April to October, a total of 7 months). The ecological flow during the dry season is typically set at 10% to 30% of the multi-year average flow, while the ecological flow during the wet season is set at 20% to 40% of the multi-year average flow. Specific values ​​can be adjusted according to river characteristics, ecosystem needs, and other factors. The calculation formula is as follows: , in: The average annual ecological flow of the i-th river segment is expressed in cubic meters per second. ); The dry season ecological flow for the i-th river segment is expressed in cubic meters per second. ); The ecological flow during the high-water season for the i-th river segment is expressed in cubic meters per second. ); The proportion of the dry season in the whole year (5 months / 12 months); The proportion of the high-water season in the whole year (7 months / 12 months).

[0048] For example, assuming the average annual flow of a controlled river section is 2.38 cubic meters per second, the ecological flow during the dry season is set at 20% of the average annual flow, i.e., 0.476 cubic meters per second; and the ecological flow during the wet season is set at 30% of the average annual flow, i.e., 0.714 cubic meters per second. Then, according to the above formula, the average annual ecological flow of this controlled river section is... cubic meters per second.

[0049] Next, based on the multi-year average flow, annual average ecological flow, and elevation difference between the control points in each controlled river section, the theoretical hydropower potential considering ecological flow constraints is calculated. The calculation of the theoretical hydropower potential considering ecological flow constraints includes: obtaining the multi-year average flow, annual average ecological flow, and elevation difference between the control points at both ends of each controlled river section; calculating the theoretical hydropower potential considering ecological flow constraints in each controlled river section based on the gravitational acceleration constant, the difference between the multi-year average flow and the annual average ecological flow, and the elevation difference between the control points at both ends of each controlled river section; and summing the theoretical hydropower potential considering ecological flow constraints in each controlled river section to obtain the theoretical hydropower potential considering ecological flow constraints. The specific calculation formula is as follows: , in: The theoretical hydropower potential considering ecological flow constraints is expressed in kilowatts (kW); 9.81 is the gravitational acceleration constant, expressed in meters per second squared (m²). ); The multi-year average flow rate of the i-th controlled river segment is expressed in cubic meters per second. ); The average annual ecological flow of the i-th river segment is expressed in cubic meters per second. ); The elevation difference between the two control points at the two ends of the i-th control segment is expressed in meters (m). This represents the summation operation on all control river segments from 1 to n-1; n is the total number of control points.

[0050] For example, continuing the previous example, assuming the average annual flow of the controlled river section is 2.38 cubic meters per second, the average annual ecological flow is 0.615 cubic meters per second, and the elevation difference is 300 meters, then the theoretical hydropower potential of this controlled river section considering ecological flow constraints is 9.81 × (2.38 - 0.615) × 300 = 5176 kilowatts. If the river has a total of 9 controlled river sections, the theoretical hydropower potential of the entire river considering ecological flow constraints can be obtained by calculating and summing the values ​​of each section.

[0051] IV. Steps for assessing the theoretical potential of hydropower resources under the constraints of ecological protection zones: like Figure 5As shown, the main steps for assessing the theoretical potential of hydropower resources under the constraints of ecological protection zones include determining whether the control point is located within the prohibited development zone of the ecological protection zone and calculating the theoretical potential of hydropower resources considering the constraints of the ecological protection zone.

[0052] First, determine whether the control point is located within the ecological protection prohibition zone. The calculation of the theoretical hydropower resource potential considering the constraints of the ecological protection zone includes: using GIS spatial connectivity tools to determine whether the control point is located within the ecological protection prohibition zone; obtaining the theoretical hydropower resource potential of the control river section located within the ecological protection prohibition zone; and calculating the theoretical hydropower resource potential considering the constraints of the ecological protection zone by subtracting the theoretical hydropower resource potential of the control river section located within the ecological protection prohibition zone from the total theoretical hydropower resource potential of the river.

[0053] In an embodiment of the invention, the spatial connection tool in ArcGIS Pro is used to spatially connect the control point layer and the ecological protection zone layer to determine whether each control point is located within the ecological protection prohibited development zone. The spatial connection method uses the point-in-polygon spatial relationship judgment, setting the search radius to 0 meters to ensure accurate judgment. Control points located within the ecological protection prohibited development zone are marked as 1, and control points not located within the ecological protection zone are marked as 0.

[0054] Next, the theoretical hydropower potential is calculated considering the constraints of ecological protection zones. According to the principles of this invention, hydropower development is prohibited in river sections located within national nature reserves. Therefore, the theoretical hydropower potential of the controlled river sections located within ecological protection zones needs to be subtracted from the total theoretical hydropower potential of the river. The specific calculation formula is as follows: , in: To take into account the theoretical potential of hydropower resources under the constraints of ecological protection zones, the unit is kilowatt (kW). The theoretical total potential of river hydropower resources is expressed in kilowatts (kW). This represents the sum of the theoretical hydropower potential of the controlled river sections located within the ecological protection and prohibited development zones, expressed in kilowatts (kW). This indicates an index for a controlled river section located within an ecological protection zone where development is prohibited.

[0055] For example, suppose the theoretical total hydropower potential of a river is 65,300 kW, of which there are two controlled river sections located within the ecological protection prohibited development zone, with theoretical hydropower potential of 7,000 kW and 8,500 kW respectively. Then, considering the constraints of the ecological protection zone, the theoretical hydropower potential of the river is 65,300 - (7,000 + 8,500) = 49,800 kW.

[0056] V. Steps for assessing the theoretical potential of hydropower resources while taking into account ecological constraints: like Figure 6 As shown, the main steps in assessing the theoretical potential of hydropower resources that take into account ecological constraints are to calculate the theoretical potential of hydropower resources that take into account ecological constraints, based on ecological flow constraints and ecological protection zone constraints.

[0057] The calculation of the theoretical hydropower resource potential taking ecological constraints into account includes: obtaining the theoretical hydropower resource potential considering ecological flow constraints; obtaining the theoretical hydropower resource potential considering ecological flow constraints in the control river section located within the ecological protection prohibited development zone; and calculating the comprehensive theoretical hydropower resource potential considering ecological constraints by subtracting the theoretical hydropower resource potential considering ecological flow constraints from the theoretical hydropower resource potential considering ecological flow constraints in the control river section located within the ecological protection prohibited development zone. The specific calculation formula is as follows: , in: The theoretical hydropower potential is given in kilowatts (kW) considering the constraints of ecological protection zones and ecological flow. The theoretical potential of hydropower resources is given in consideration of ecological flow constraints, and the unit is kilowatt (kW). The sum of theoretical hydropower potential for controlled river sections located in nature reserves, taking into account ecological flow constraints, is expressed in kilowatts (kW). This indicates an index for a controlled river section located within an ecological protection zone.

[0058] For example, suppose the theoretical hydropower potential of a river considering ecological flow constraints is 48,000 kW, of which the theoretical hydropower potential of the control river section located within the ecological protection zone considering ecological flow constraints is 5,200 kW and 6,300 kW respectively. Then the theoretical hydropower potential of the river considering ecological constraints is 48,000 - (5,200 + 6,300) = 36,500 kW.

[0059] Through the above steps, this invention automates and standardizes the hydropower resource assessment process, fully considers ecological constraints, ensures the ecological health of rivers, and reasonably assesses the theoretical reserves of hydropower resources, providing a scientific basis for hydropower development decisions.

[0060] like Figures 7 to 9 As shown, the effectiveness of the method of the present invention has been verified through the application of practical cases. Figure 7 It shows the changes in hydropower reserves under various constraints. Figure 8 It shows the spatial relationship between site traffic distribution and ecological protection zones. Figure 9The comparison and analysis of installed capacity and hydropower potential were presented, verifying the rationality of the assessment results.

[0061] Practice has shown that the method of this invention improves assessment efficiency by more than 80% and significantly enhances assessment accuracy compared with traditional assessment methods. At the same time, it fully considers the needs of ecological protection and provides important technical support for the sustainable development of hydropower resources.

[0062] The above description is merely a preferred embodiment of the present invention and does not limit the scope of patent protection of the present invention. Any equivalent structural transformations made based on the inventive concept of the present invention and the contents of the specification and drawings of the present invention, or direct / indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A method for assessing hydropower resources based on GIS technology and considering ecological constraints, characterized in that, Includes the following steps: The data preparation steps include acquiring digital elevation model, hydropower station coordinates, nature reserve boundaries, and multi-year average runoff depth data; based on the digital elevation model, extracting hydrological data on river network, cumulative flow, flow direction, dumping point, catchment area, and catchment area; and based on the catchment area and multi-year average runoff depth data, calculating the multi-year average runoff depth and multi-year average flow of the catchment area. The steps for calculating the theoretical potential of hydropower resources are as follows: the river is divided into multiple control sections by using the discharge point as the control point, each control section corresponds to a catchment area, and the multi-year average flow of the catchment area is used as the multi-year average flow of the control section. Calculate the elevation difference between adjacent control points; Based on the elevation difference of the control points and the multi-year average flow of the control river section, the theoretical hydropower potential of the control river section is calculated; the theoretical hydropower potential of each control river section is summed to obtain the total theoretical hydropower potential of the river. Steps for assessing the theoretical potential of hydropower resources under ecological flow constraints, including calculating the average annual ecological flow; Based on the multi-year average flow of the controlled river section, the annual average ecological flow, and the elevation difference of the control point, the theoretical potential of hydropower resources considering ecological flow constraints is calculated. The steps for assessing the theoretical potential of hydropower resources under the constraints of ecological protection zones include: determining whether the control point is located within the ecological protection prohibited development zone; and calculating the theoretical potential of hydropower resources considering the constraints of ecological protection zones based on the total theoretical potential of the river's hydropower resources and the theoretical potential of the hydropower resources of the control river section located within the ecological protection prohibited development zone. The theoretical hydropower resource potential assessment steps taking into account ecological constraints are as follows: based on the theoretical hydropower resource potential considering ecological flow constraints and the theoretical hydropower resource potential considering ecological flow constraints in the controlled river section located in the ecological protection prohibited development zone, the theoretical hydropower resource potential considering ecological flow constraints is calculated.

2. The method according to claim 1, characterized in that, The calculation of the multi-year average runoff depth of the catchment area includes: Obtain the multi-year average runoff depth and area of ​​each grid within the catchment area; The multi-year average runoff depth of the catchment area is calculated by weighted averaging based on the multi-year average runoff depth and area of ​​each grid within the catchment area.

3. The method according to claim 1, characterized in that, The calculation of the multi-year average flow of the catchment area includes: Obtain the catchment area and the average annual runoff depth of the catchment area; The average annual flow rate of the catchment area is calculated based on the catchment area, the average annual runoff depth of the catchment area, and the time conversion factor.

4. The method according to claim 1, characterized in that, The calculation of the elevation difference between adjacent control points includes: Obtain the elevation values ​​of adjacent control points; Calculate the difference in elevation between adjacent control points to obtain the elevation difference between the control points at both ends of the controlled river section.

5. The method according to claim 1, characterized in that, The calculation of the theoretical hydropower potential of the controlled river section includes: Obtain the multi-year average flow of the controlled river section and the elevation difference between the control points at both ends of the controlled river section; Based on the gravitational acceleration constant, the multi-year average flow of the controlled river section, and the elevation difference between the two ends of the controlled river section, the theoretical hydropower potential of the controlled river section is calculated.

6. The method according to claim 1, characterized in that, The calculation of the theoretical total potential of river hydropower resources includes: To obtain the theoretical hydropower potential of each controlled river section; The theoretical hydropower potential of each controlled river section is summed to obtain the total theoretical hydropower potential of the river.

7. The method according to claim 1, characterized in that, The calculation of the average annual ecological flow includes: The year is divided into a dry season and a wet season. Obtain the ecological flow during the dry season and the ecological flow during the wet season of the controlled river section; Based on the ecological flow during the dry season, the ecological flow during the wet season, and their respective time proportions throughout the year, the average annual ecological flow of the controlled river section is calculated.

8. The method according to claim 7, characterized in that, The calculation of the theoretical potential of hydropower resources considering ecological flow constraints includes: Obtain the multi-year average flow, annual average ecological flow, and elevation difference between the two ends of the control point in each control section; Based on the gravitational acceleration constant, the difference between the multi-year average flow and the annual average ecological flow of the controlled river section, and the elevation difference between the control points at both ends of the controlled river section, the theoretical hydropower potential of each controlled river section considering ecological flow constraints is calculated. The theoretical hydropower resource potential considering ecological flow constraints in each controlled river section is summed to obtain the theoretical hydropower resource potential considering ecological flow constraints.

9. The method according to claim 1, characterized in that, The calculation of the theoretical hydropower resource reserves considering the constraints of ecological protection zones includes: Use GIS spatial connection tools to determine whether control points are located within ecological protection prohibited development zones; To obtain the theoretical hydropower potential of the controlled river sections located within ecological protection and prohibited development zones; The theoretical hydropower potential of the river is calculated by subtracting the theoretical hydropower potential of the controlled river section located within the ecological protection and prohibited development zone from the total theoretical potential of the river's hydropower resources. This calculation takes into account the constraints of the ecological protection zone.

10. The method according to claim 1, characterized in that, The calculation of the theoretical potential of hydropower resources, taking into account ecological constraints, includes: To obtain the theoretical potential of hydropower resources considering ecological flow constraints; To obtain the theoretical hydropower potential of the controlled river section located within the ecological protection and prohibited development zone, taking into account ecological flow constraints; The theoretical hydropower resource reserve considering ecological constraints is calculated by subtracting the theoretical hydropower resource reserve considering ecological flow constraints from the theoretical hydropower resource reserve considering ecological flow constraints in the controlled river section located in the ecological protection prohibited development zone.

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