Method for evaluating carbon emission of traffic travel based on built environment index

Abstract

This invention discloses a method for assessing carbon emissions from transportation based on built environment indicators. The method includes: constructing a built environment indicator system encompassing five categories: density, accessibility, design, diversity, and demand; and standardizing and assigning values ​​to each built environment indicator in the target area. Subsequently, by weighted superposition of the standardized and assigned values ​​of the built environment indicators, the comprehensive attraction index of the target area's built environment to different modes of transportation is calculated, thereby predicting the travel mode share of each mode of transportation. Based on this, considering the differentiated emission factors of fossil fuel and electric-driven travel modes, the annual emissions of carbon dioxide and air pollutants generated by regional transportation are further quantitatively assessed. This method can systematically quantify the impact of the built environment on mode of transportation selection and carbon emissions, providing a scientific basis for green and low-carbon oriented urban design and transportation planning.

Description

Technical Field

[0001] This invention relates to the field of carbon emission assessment technology for transportation, and specifically to a method for assessing carbon emission from transportation based on built environment indicators. Background Technology

[0002] In the transportation sector, reducing carbon and air pollutant emissions is a key objective of current urban green development. To achieve this, a scientific assessment of the impact of the urban built environment on residents' transportation choices and transportation emissions is necessary. Transportation emissions primarily originate from fossil fuel- or electrically powered modes of transportation, such as private cars, buses, and subways; related pollutants include carbon monoxide (CO) and nitrogen oxides (NOx). x Hydrocarbons (HC) and fine particulate matter (PM) 2.5 coarse particulate matter (PM) 10 And sulfur dioxide (SO2), etc. In recent years, with the continuous advancement of public transportation and slow-moving transportation systems, as well as the increasing demand for urban renewal, identifying the potential of built environment optimization to promote low-carbon transportation modes is of great significance for reducing urban transportation carbon emissions and air pollutant emissions.

[0003] While current technologies can analyze the impact of the built environment on travel patterns, most remain qualitative, lacking quantitative assessment methods focused on emissions outcomes. For example, predictions of traffic carbon emissions and major air pollutant emissions typically rely on existing travel pattern shares and specific point-in-time environmental conditions, making it difficult to systematically characterize the changing characteristics and potential differences in traffic emissions under different built environment conditions. Therefore, existing technologies struggle to provide scientific and effective pre-assessment basis for low-carbon or low-emission guidance in urban planning or design schemes, thus limiting the identification of potential optimization areas and the screening, comparison, and application of relevant optimization measures.

[0004] Therefore, it is necessary to establish an assessment method that can quantify the impact of urban built environment indicators on transportation behavior and related carbon emissions. This method can serve the optimization of urban design and planning schemes, and is particularly suitable for Transit-Oriented Development (TOD) projects and urban renewal projects aimed at reducing transportation emissions. Specifically, this method should be able to predict the share of residents' transportation modes under different built environment conditions, and conduct a bottom-up quantitative assessment of carbon emissions and air pollutant emissions generated by transportation based on the principle of activity level × emission factor. Based on this, it can provide a basis for comparing different urban design schemes, identifying potential optimization areas, and screening and comparing relevant optimization measures, thereby providing scientific support for low-carbon urban development and green transportation planning. Summary of the Invention

[0005] To overcome the aforementioned problems in the existing technology, this invention provides a method for assessing carbon emissions from transportation based on built environment indicators, which can realize quantitative analysis of the entire process from built environment characterization to transportation emission assessment.

[0006] According to a first aspect of the present invention, a method for assessing carbon emissions from transportation based on built environment indicators is provided, the method comprising: Establish a built environment indicator system that includes density, accessibility, design, diversity, and demand indicators, and standardize and assign values ​​to each built environment indicator in the target area. In response to the built environment indicator system, the comprehensive attraction level index of the target built environment to various modes of transportation is calculated by weighting and superimposing the standardized graded values ​​of the built environment indicators of the target area. The weight coefficients are determined according to the degree of influence of the indicators on the modes of transportation. The modes of transportation considered include private car travel, public transportation, subway travel, electric bicycle travel, shared bicycle travel, and walking. In response to the calculated comprehensive attraction level index, a normalization method is used to predict the travel mode share of each mode of transportation in the target built environment; Based on the predicted travel mode share and combined with the total annual travel distance of each mode of transportation, fossil fuel-driven and electric-driven modes are distinguished, and corresponding carbon dioxide emission factors and air pollutant emission factors per unit mileage are used to quantitatively assess the carbon emissions and air pollutant emissions of transportation in the target built environment.

[0007] Furthermore, the built environment density index can be expanded to include, but is not limited to, at least one of population density, employment density, and building density.

[0008] Furthermore, the indicators of accessibility in the built environment can be expanded to include, but are not limited to, at least one of the following: the number of bus stops, accessibility to subway stations, distance from the city center, and accessibility to shared bicycle stations.

[0009] Furthermore, the built environment design indicators can be expanded to include, but are not limited to, at least one of road density, intersection density, and the number of bus routes.

[0010] Furthermore, the built environment diversity index can be expanded to include, but is not limited to, at least one of land use mix and number of points of interest.

[0011] Furthermore, the built environment demand indicators can be expanded to include, but are not limited to, at least one of the following: the number of parking spaces and the capacity of shared bicycle stations.

[0012] According to a second aspect of the present invention, a computer program product is provided, comprising a computer program that, when executed by a processor, implements the methods provided in the embodiments of the present disclosure.

[0013] The beneficial effects of this invention are as follows: By constructing a built environment indicator system, it assesses the comprehensive attractiveness of various transportation modes under different built environment conditions, predicts the share of different transportation modes, and further quantifies the carbon emissions and air pollutant emissions generated by transportation. This provides integrated technical support for transportation environmental benefit assessment for green and low-carbon-oriented urban renewal and public transport priority planning. This invention achieves a bottom-up quantitative assessment of changes in transportation carbon emissions and major air pollutant emissions caused by urban design or planning schemes, providing a scientific basis for comparing, selecting, and optimizing different schemes, and supporting urban design optimization and implementation performance evaluation under low-carbon goals. This method is applicable to environmentally friendly decision-making and design optimization within rail transit stations and their 1000-meter radius. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the process for assessing carbon emissions from transportation based on built environment indicators, according to the present invention. Figure 2 This is a schematic diagram illustrating the research process for the impact of the built environment on residential traffic carbon emissions and air pollutant emissions according to the present invention. Detailed Implementation

[0015] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of this application.

[0016] While existing technologies can analyze the impact of the built environment on transportation behavior to some extent, there is a lack of assessment methods that can further quantify its impact on carbon emissions and air pollutant emissions from transportation. Therefore, it is difficult to provide a basis for pre-assessment of urban planning or design projects with a focus on low-carbon and low-emission transportation goals.

[0017] To address the problems existing in current technologies, see [reference] Figures 1-2 This embodiment provides a method for assessing carbon emissions from transportation based on built environment indicators. This method is particularly suitable for assessing carbon dioxide and air pollutant emissions from rail transit stations and their 1000-meter radius. The specific implementation steps of this method are as follows: S1. Establish a built environment indicator system that includes density, accessibility, design, diversity, and demand indicators, and standardize and assign values ​​to each built environment indicator in the target area.

[0018] Specifically, built environment density indicators include, but are not limited to, at least one of population density, employment density, and building density. Population density represents the number of residents per unit area; employment density represents the number of employed people per unit area; and building density represents the building area per unit area. By introducing density indicators, the impact of spatial development intensity on residents' travel demand and mode of transportation choices can be accurately characterized, thereby improving the accuracy of travel structure prediction.

[0019] Accessibility indicators for the built environment include, but are not limited to, at least one of the following: number of bus stops, accessibility to subway stations, distance from the city center, and accessibility to shared bicycle stations. Specifically, the number of bus stops represents the number of bus stops within a 100-meter buffer zone around the point of interest; subway station accessibility represents the distance from the entrance / exit of the community where the point of interest is located to the nearest subway station entrance / exit; distance from the city center represents the distance from the point of interest to the city center; and shared bicycle station accessibility represents the distance from the entrance / exit of the community where the point of interest is located to the nearest shared bicycle parking spot. By introducing accessibility indicators, the degree to which the built environment supports accessibility to various modes of transportation can be comprehensively assessed, strengthening the correlation between the assessment results and residents' actual activity needs.

[0020] Built environment design indicators include, but are not limited to, at least one of road density, intersection density, and the number of bus routes. Road density is represented by the total length of roads within a 100m radius buffer zone around the point of interest, divided by the buffer zone area; intersection density is represented by the number of intersections within a 100m radius buffer zone around the point of interest, divided by the buffer zone area; and the number of bus routes is represented by the number of bus routes within a 100m radius buffer zone around the point of interest. By incorporating design indicators that more directly reflect street space design and pedestrian-friendly features, the potential impact of urban design indicators on encouraging pedestrian travel and reducing reliance on motor vehicles can be effectively assessed, providing a direct basis for refined urban design aimed at low-carbon goals.

[0021] Built environment diversity indicators include, but are not limited to, at least one of land use mixing degree and number of Points of Interest (POIs). Land use mixing degree can be characterized by the land use entropy index, expressed as: ;

[0022] p i It is the first i The proportion of land use categories NThis represents the number of land use categories; the number of POIs indicates the number of POIs within a 100m buffer zone of the point of interest. By introducing diversity indicators, the richness of land use and service function configuration in the region can be characterized.

[0023] Built environment demand indicators include, but are not limited to, at least one of the following: the number of car parking spaces and the capacity of shared bicycle stations. The number of car parking spaces represents the total number of car parking spaces in the study area; the capacity of shared bicycle stations represents the total number of shared bicycle parking spaces in the study area. By introducing demand indicators, we can more comprehensively depict the degree to which built environment facilities satisfy or inhibit the demand for various modes of transportation, thereby more accurately predicting the travel structure.

[0024] Furthermore, the aforementioned built environment indicators need to be standardized and graded. This standardized grading and grading refers to dividing the original measured values ​​of each built environment indicator into multiple levels based on a preset threshold range and assigning corresponding standardized values ​​to each. For example, based on planning control standards or regional distribution levels, they can be divided into four levels and assigned values ​​of 0, 30, 60, and 100 respectively, to characterize the degree of differentiated support provided by different levels of built environment indicators to various travel modes. Through this process, continuous built environment data can be transformed into comparable grade scores, facilitating subsequent weighted overlay calculations.

[0025] S2. In response to the built environment indicator system, the comprehensive attraction level index of the target built environment to various modes of transportation is calculated by weighting and superimposing the standardized and graded values ​​of the built environment indicators of the target area. LOI m The weighting coefficients are determined based on the degree of influence of the indicators on transportation modes, and the transportation modes considered include private car travel, public transportation, subway travel, electric bicycle travel, shared bicycle travel, and walking.

[0026] Specifically, the formula for calculating the comprehensive attractiveness index of the built environment to a specific mode of transportation is as follows: ; In the formula, any mode of transportation m The overall attraction level index is LOI m , BE i This represents the standardized value of the built environment indicator. ω i,m This indicator represents the impact of transportation modes. m The influence weighting coefficient, where, LOI m The higher the value, the more attractive the mode of transportation is in the current built environment.

[0027] S3. In response to the calculated comprehensive attraction level index, a normalization method is used to predict the travel mode share of each mode of transportation in the target built environment.

[0028] Specifically, after obtaining the comprehensive attractiveness index of each mode of transportation, the travel mode share of different modes of transportation can be estimated through normalization. S m The expression is as follows: .

[0029] It should be noted that in practical applications, it is not advisable to overemphasize the precise share of travel modes, but rather to focus on changes in travel structure under different built environments (such as the differences in travel structure between public transport-oriented and private car-oriented travel).

[0030] S4. Based on the predicted travel mode share and combined with the total annual travel distance of each mode of transportation, distinguish between fossil fuel-driven and electric-driven modes, and use the corresponding carbon dioxide emission factor and air pollutant emission factor per unit mileage to quantitatively assess the carbon emissions and air pollutant emissions of transportation in the target built environment.

[0031] This embodiment, at the emissions accounting level, not only covers carbon dioxide (CO2), but also encompasses a variety of air pollutants, including carbon monoxide (CO) and nitrogen oxides (NOx) generated by fossil fuel-powered transportation. x Hydrocarbons (HC) and particulate matter (PM) 2.5 PM 10 And sulfur dioxide (SO2), as well as CO and NO corresponding to electric-powered travel. x PM 2.5 PM 10 And SO2. By distinguishing between the pollutants emitted by fossil fuel-driven and electric-driven modes of transportation, we can more accurately reflect the true environmental impact of different modes of transportation, providing urban planners with a more comprehensive basis for environmental benefit assessment, thereby enabling them to make more scientific and balanced decisions under the goal of green and low-carbon development.

[0032] Specifically, it includes the following steps: S401, Annual carbon dioxide emissions from transportation activities within the study area E c And calculate according to the following formula: ;

[0033] In the formula, VKT m,k Indicates the type of energy used k mode of transportation m The corresponding total annual travel distance, in km / y; CEm,k Indicates fuel k Driven by travel mode m The carbon dioxide emission factor is expressed in kg / km.

[0034] S402. For fossil fuel-driven transportation modes, the carbon dioxide emission factor is determined by the following formula: ;

[0035] In the formula, CE m,f This represents the carbon dioxide emission factor per unit mile of fossil fuel energy. G m,f This indicates fuel consumption per unit distance, expressed in kg / km. q f Indicates fuel f The lower heating value, expressed in TJ / g; CEF f Indicates fuel f Carbon dioxide emission intensity per unit of calorific value, expressed in kg / TJ.

[0036] For electrically powered transportation, the carbon dioxide emission factor is determined by the following formula: ;

[0037] In the formula, CE m,e This represents the carbon dioxide emission factor per unit distance of electric drive. G m,e This indicates the electricity consumption per unit distance, expressed in kWh / km. CEF g,e This represents the regional power grid carbon emission factor, expressed in kg / kWh. It is recommended that this factor be calculated using a weighted method that combines operational and construction margins, and updated based on the region's annual power structure.

[0038] S403. For fossil fuel-driven transportation modes, the emissions of CO and NO... x HC, PM 2.5 and PM 10 Annual emissions of various air pollutants M j The determination is based on vehicle mileage and air pollutant emission factors, as shown in the following formula: ;

[0039] In the formula, VKT m,f Indicates the use of fossil fuels f Driven by travel mode mThe corresponding total annual travel distance, in km / y. PEF m,s,f,j Indicates the type of energy used. f mode of transportation m In emission standards s air pollutants below j The emission factor, measured in g / km, can be adjusted based on the national "Technical Guidelines for the Compilation of Emission Inventory of Road Motor Vehicles" and in combination with local meteorological conditions, driving conditions and fuel quality. P s This indicates the percentage of vehicles that meet different emission standards. M j This indicates the total annual emissions of various air pollutants.

[0040] SO2 emissions are calculated using the fuel sulfur content mass balance method, as shown in the following formula: ;

[0041] In the formula, Q g and Q d These are the annual consumption of gasoline and diesel for transportation, respectively, in tons. α g and α d These are the sulfur contents of gasoline and diesel, respectively, in ppm.

[0042] For electrically powered transportation, air pollutant emissions mainly originate from upstream power generation. j Annual emissions M e,j Calculate using the following formula: ;

[0043] In the formula, VKT m,e Indicates the use of electric transportation. m The corresponding total annual travel distance, in km / y. M e,j Indicates air pollutants j Annual emissions; PEF e,j The air pollutant emission factor representing the total power generation of the power grid can be determined based on the regional power emission inventory, and the unit is g / km; η c,m Indicates the charging efficiency of the vehicle model; λ l This indicates the power transmission and distribution loss rate.

[0044] Ultimately, by integrating data on travel volume, travel distance, and emission factors of various modes of transportation, the total annual carbon emissions and total emissions of various air pollutants generated by transportation within the region are calculated, providing a scientific basis for the formulation or optimization of urban design or planning schemes guided by green and low carbon principles.

[0045] In a preferred embodiment, in order to characterize the continuous change characteristics of the built environment within the target area, when measuring the various built environment indicators of the target area, the target area is first divided into 10 m × 10 m grid units, and the indicators are calculated using the grid as the basic unit; on this basis, the various built environment indicators are standardized and graded and assigned values, and the assignment rules are shown in Table 1 below.

[0046] Table 1. Classification and Value Assignment Rules for Built Environment Indicators index Assignment rules population density Number of residents per unit area within each 10 m × 10 m grid Employment density Number of employed people per unit area within each 10 m × 10 m grid Building density The ratio of the total building area to the land area within each 10 m × 10 m grid, assigned values ​​according to the following intervals: ≥9:100; 6–9:60; 3–6:30; 0–3:0 Number of bus stops A 100 m buffer zone is generated at the center of each 10 m × 10 m grid. The number of bus stops within the buffer zone is counted and assigned values ​​according to the following intervals: ≥6: 100; 4–6: 60; 2–4: 30; 0–2: 0. Distance from city center The distance from the center of each 10 m × 10 m grid to the city center road network is assigned according to the following intervals: ≥15 km: 100; 10–15 km: 60; 5–10 km: 30; ≤5 km: 0 subway station accessibility The shortest distance from the center of each 10 m × 10 m grid to the subway entrance / exit is calculated and assigned values ​​according to the following intervals: ≤300 m: 100; 300–600 m: 60; 600–900 m: 30; ≥900 m: 0 Accessibility of shared bicycle stations The shortest distance from the center of each 10 m × 10 m grid to the shared bicycle station is calculated and assigned values ​​according to the following intervals: ≤200 m: 100; 200–400 m: 60; 400–600 m: 30; ≥600 m: 0 Land use mix Land use entropy index within each 10m×10m grid is assigned values ​​according to the following intervals: ≥0.9: 100; 0.6–0.9: 60; 0.3–0.6: 30; 0–0.3: 0 Number of POIs A 100 m buffer is generated at the center of each 10 m × 10 m grid. The total number of POIs within the buffer is counted, and values ​​are assigned according to the following intervals: ≥1200: 100; 800–1200: 60; 400–800: 30; 0–400: 0 Road density Calculate the ratio of the total road length to the buffer zone area within a 100 m buffer zone, and assign values ​​according to the following intervals: Excluding pedestrian walkways: ≥0.018:100; 0.012–0.018:60; 0.006–0.012:30; 0–0.006:0; Including pedestrian walkways: ≥0.03:100; 0.02–0.03:60; 0.01–0.02:30; 0–0.01:0 Number of bus routes Number of bus routes within a 100 m buffer zone, assigned values ​​according to the following intervals: ≥6: 100; 4–6: 60; 2–4: 30; 0–2: 0 Intersection density Calculate the ratio of the number of road intersections to the buffer area within a 100 m buffer zone, and assign values ​​according to the following intervals: Excluding pedestrian walkways: ≥0.0003: 100; 0.0002–0.0003: 60; 0.0001–0.0002: 30; 0–0.0001: 0; Including pedestrian walkways: ≥0.0006: 100; 0.0004–0.0006: 60; 0.0002–0.0004: 30; 0–0.0002: 0 Parking space capacity The number of parking spaces for motor vehicles within each 10 m × 10 m grid, assigned according to the following intervals: ≥90: 100; 60–90: 60; 30–60: 30; 0–30: 0 Shared bike station capacity The number of shared bicycle parking spaces within each 10 m × 10 m grid, assigned according to the following intervals: ≥15: 100; 10–15: 60; 5–10: 30; 0–5: 0 Weighting coefficients of built environment indicators ω i,m As shown in Table 2 below.

[0047] Table 2 Weighting coefficients of built environment indicators index private cars Bus subway electric bicycle shared bicycles walk population density 10 10 15 15 15 10 Employment density 5 10 20 25 Building density 15 10 15 10 Number of bus stops 20 Distance from city center 15 Subway accessibility 30 Accessibility of shared bicycle stations 15 Land use mix 30 15 15 20 15 25 Number of POIs 10 15 35 10 10 Road density 15 10 20 10 15 Number of bus routes 10 Intersection density 10 10 10 15 Parking space capacity 5 Shared bike station capacity 5 In practical applications, this method can flexibly select and evaluate relevant indicators by combining the built environment characteristics and data availability of different cities, in order to characterize the impact level on different modes of transportation under different built environment conditions, thereby improving the applicability and reliability of the assessment results. By implementing this method, the impact of built environment indicators on carbon emissions and air pollutant emissions from transportation can be quantitatively analyzed, providing a scientific basis for low-carbon city planning and design, transportation emission reduction, and related scheme optimization.

[0048] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A method for assessing carbon emissions from transportation based on built environment indicators, characterized in that, The method includes: Establish a built environment indicator system that includes density, accessibility, design, diversity, and demand indicators, and standardize and assign values ​​to each built environment indicator in the target area. In response to the built environment indicator system, the comprehensive attraction level index of the target built environment to various modes of transportation is calculated by weighting and superimposing the standardized graded values ​​of the built environment indicators of the target area. The weight coefficients are determined according to the degree of influence of the indicators on the modes of transportation. The modes of transportation considered include private car travel, public transportation, subway travel, electric bicycle travel, shared bicycle travel, and walking. In response to the calculated comprehensive attraction level index, a normalization method is used to predict the travel mode share of each mode of transportation in the target built environment; Based on the predicted travel mode share and combined with the total annual travel distance of each mode of transportation, fossil fuel-driven and electric-driven modes are distinguished, and corresponding carbon dioxide emission factors and air pollutant emission factors per unit mileage are used to quantitatively assess the carbon emissions and air pollutant emissions of transportation in the target built environment.

2. The method for assessing carbon emissions from transportation as described in claim 1, characterized in that, Built environment density indicators can be expanded to include, but are not limited to, at least one of population density, employment density, and building density.

3. The method for assessing carbon emissions from transportation as described in claim 1, characterized in that, The indicators of accessibility of the built environment can be expanded to include, but are not limited to, at least one of the following: number of bus stops, accessibility of subway stations, distance from the city center, and accessibility of shared bicycle stations.

4. The method for assessing carbon emissions from transportation as described in claim 1, characterized in that, Built environment design indicators can be expanded to include, but are not limited to, at least one of road density, intersection density, and number of bus routes.

5. The method for assessing carbon emissions from transportation as described in claim 1, characterized in that, The built environment diversity index can be expanded to include, but is not limited to, at least one of land use mix and number of points of interest.

6. The method for assessing carbon emissions from transportation as described in claim 1, characterized in that, The built environment demand indicators can be expanded to include, but are not limited to, at least one of the following: the number of parking spaces and the capacity of shared bicycle stations.

7. The method for assessing carbon emissions from transportation according to claim 1, characterized in that, The formula for calculating the overall attractiveness index of the built environment to a specific mode of transportation is as follows: ； In the formula, any mode of transportation m The overall attraction level index is LOI m , BE i This represents the standardized value of a specific built environment indicator. ω i,m This indicator represents the impact of transportation modes. m The influence weighting coefficient, where, LOI m The higher the value, the more attractive the current built environment is to that mode of transportation.

8. The method for assessing carbon emissions from transportation according to claim 1, characterized in that, For fossil fuel-driven transportation modes, the carbon dioxide emission factor is determined by the following formula: ； In the formula, CE m,f This represents the carbon dioxide emission factor per unit mile from fossil fuels. G m,f This indicates fuel consumption per unit distance. q f Indicates fuel f Low heat generation, CEF f Indicates fuel f Carbon dioxide emission intensity per unit calorific value; Its air pollutant emission factor is based on the use of fossil fuels. f mode of transportation m In emission standards s pollutants below j Emission factors PEF m,s,f,j 。 9. The method for assessing carbon emissions from transportation according to claim 1, characterized in that, For electrically powered transportation modes, the carbon dioxide emission factor is determined by the following formula: ； In the formula, CE m,e This represents the carbon dioxide emission factor per unit distance of electric drive. G m,e This indicates the electricity consumption per unit distance. CEF g,e Indicates the carbon dioxide emission factor of the regional power grid; Its air pollutant emission factor is the air pollutant emission factor of the integrated power generation of the power grid. PEF e,j It can be determined based on the regional electricity emissions inventory.

10. A computer program product comprising a computer program that, when executed by a processor, implements the method according to any one of claims 1 to 9.

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