Method for estimating carbon dioxide emission in vehicle electrification process

Abstract

The invention belongs to the technical field of waste treatment, and particularly relates to a method for estimating carbon dioxide emission in a vehicle electronization process, which comprises the following steps of: compiling a coefficient by taking the carbon emission of a traditional ICE engine as a baseline, and representing the change condition of carbon emission intensity in a battery production process; cO2 emission related to vehicle use and emission related to fuel production and combustion are calculated, and carbon emission data are obtained; the carbon emission data is compared to a baseline to derive a carbon emission difference to compare the carbon emission footprints of various powertrains and their carbon emissions at incremental electrification levels of various light vehicles, thereby enabling the selection of relevant parameters for the production and use of the vehicles, such as the use of the vehicles, as well as the use of the vehicles. A simplified tool for various powertrain alternatives is provided for analyzing the carbon emission level and impact of the electrified powertrain of the vehicle, which is easy to use and compare.

Description

Technical Field

[0001] The present invention belongs to the technical field of waste treatment, and in particular relates to a method for estimating carbon dioxide emissions during vehicle electrification. Background Art

[0002] The current emphasis on carbon dioxide (CO2) emissions from light-duty vehicles (LDVs) makes it easy to conclude that battery electric vehicles (BEVs) are superior to any other powertrain solution when limiting the analysis to tank-to-wheels, as they produce virtually no CO2 during use. However, the conclusion that has been demonstrated varies depending on a variety of factors, among which one can cite the carbon intensity of the electricity used in the production of the battery, the carbon intensity of the electricity used to charge the BEV, the battery capacity, the necessity to electrically heat the BEV cabin in cold weather, the losses in the charging system, the losses between the turbine and the grid and the losses through the grid, among others. As a result, modeling for this problem is very complex with multiple parameters.

[0003] When considering the life cycle assessment (LCA) of batteries, BEVs cannot be considered “CO2-neutral” despite the fact that BEVs produce virtually no chemicals during use. The CO2 emissions here refer to those diverted from combustion to generate electricity and the production of electricity.

[0004] When studying the minimization of carbon dioxide (CO2) emissions from road transport, the need for tools that can compare various powertrain options is crucial. The work of many researchers has demonstrated the need to consider the entire life cycle assessment (LCA), also using simplified tank-to-wheel calculation methods, but these studies are not satisfactory in providing guidance for optimizing technology selection based on variable manufacturing and operating conditions. Summary of the invention

[0005] The object of the present invention is to provide a method for estimating carbon dioxide emissions during vehicle electrification to solve the problems in the prior art mentioned in the above background technology.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A method for estimating carbon dioxide emissions during vehicle electrification includes: compiling a coefficient based on the carbon emissions of a traditional ICE engine as a baseline, the coefficient representing the change in carbon emission intensity during battery production; calculating CO2 emissions related to vehicle use, fuel production and combustion-related emissions to obtain carbon emission data; comparing the carbon emission data with the baseline to obtain a carbon emission difference.

[0008] Specifically, the emissions associated with fuel production and combustion include emissions from the combustion process and fuel production, and emissions associated with the production of electricity used to charge battery electric vehicles.

[0009] Specifically, the coefficient is CBatt*fprod,

[0010] The formula is: ΔCO2Prod = α*β*(CBatt*fprod);

[0011] Where α is the energy ratio required to produce 1 kWh of battery, CBatt*fprod is the carbon intensity of the battery production process, and β is the sedimentation coefficient used to reflect the reduction in vehicle mass associated with the removal of the engine and other components.

[0012] Specifically, the emission calculation formula related to fuel production and combustion is:

[0013] CO2ICEusage=CO2Combustion*Fuel prod factor=(23.388.6*106*Energyconsumption ICE)*1.1236*D;

[0014] Where CO2ICEusage is the carbon emission of the ICE engine, D is the driving distance, and CO2Combustion is the carbon emission during the combustion process.

[0015] Specifically, the calculation formula for the emissions associated with the electricity production for charging the battery electric vehicle is:

[0016] CO2BEVusage =ηAC_Heat*ηcharging / (ηprod*ηnetwork*105) *EnergyconsumptionBEV*fusage*D

[0017] Where CO2BEVusage is the carbon emissions from the use of battery electric vehicles, ηAC_Heat is equal to 1.1, ηcharging is 1.15, ηprod is 0.93, and ηnetwork is 0.95.

[0018] Specifically, the calculation formula for the carbon emission difference is:

[0019]

[0020] In the formula, δ1 and δ2 represent the relative increase coefficient of energy consumption of plug-in hybrid electric vehicle PHEV in pure fuel and pure electric modes compared with pure electric vehicle BEV, the energy consumption ratio γ of BEV is 3, UF is the charging facility coefficient, and f usage The maximum carbon intensity of the network for charging electric vehicles.

[0021] Specifically, the application formula of the charging facility coefficient UF is:

[0022]

[0023] Technical effects and advantages of the present invention: Compared with the prior art, the method for estimating carbon dioxide emissions during vehicle electrification proposed by the present invention has the following advantages:

[0024] The present invention compiles a coefficient based on the carbon emissions of traditional ICE engines as a baseline, and the coefficient represents the change in carbon emission intensity during the battery production process; calculates CO2 emissions related to vehicle use, fuel production and combustion-related emissions to obtain carbon emission data; compares the carbon emission data with the baseline to obtain carbon emission differences to compare the carbon emission footprints of various powertrains, as well as their carbon emissions at incremental electrification levels of various light vehicles, so that relevant parameters can be selected for vehicle production and use, and a simplified tool for analyzing the carbon emission levels and impacts of the power structure of vehicle electrification is provided for various powertrain alternatives, which is easy to use and compare. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The present invention is a flow chart of a method for estimating carbon dioxide emissions during vehicle electrification. DETAILED DESCRIPTION

[0026] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. The specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0027] The purpose of this invention is to establish a more general model and a relatively practical tool to compare the carbon footprint of various powertrains with increasing levels of electrification of light-duty vehicles (conventional engine-driven vehicles, full hybrids, plug-in hybrids and pure battery electric vehicles). On a sequential basis, it will make it possible to select relevant powertrain parameters when the vehicle is produced and operated.

[0028] In an embodiment of the present invention, a method for estimating carbon dioxide emissions during vehicle electrification is provided. For example, Figure 1 As shown, the following steps are included:

[0029] Step 1: Compile a coefficient based on the carbon emissions of traditional ICE engines, which represents the change in carbon emission intensity during the battery production process.

[0030] Specifically, first, this embodiment decides not to use the traditional method of providing absolute CO2 amounts for option power parameter analysis, but to use a novel comparison method that provides a direct comparison method with a traditional engine-powered vehicle as a baseline. In terms of vehicle production CO2 emissions, this move can get rid of the time / mileage variable and compile a unique coefficient CBatt*fprod that represents how the intensity of carbon emissions changes during the battery production process. Assuming that most of the difference in production-related CO2 emissions between traditional ICE and BEV vehicles comes simply from battery production, it can be expressed as (1) in tons of CO2.

[0031] The formula is: ΔCO2Prod=α*β*(CBatt*fprod) (1)

[0032] In the formula, α is the energy ratio required to produce 1kWh of battery, CBatt*fprod is the carbon intensity (CO2 production intensity) in the battery production process, expressed in kilograms of carbon dioxide kgCO2 (CBatt is expressed in kilowatt-hours kWh, fprod is expressed in kgCO2kWh), and β is a sedimentation coefficient used to reflect the reduction in vehicle mass due to the removal of the engine and other components (i.e., reducing carbon dioxide emissions, because emissions are expected to be proportional to the chassis mass). The BEV is rated at 0.9 (i.e., excluding batteries, the mass is reduced by 10%), and the PHEV is rated at 1 (i.e., since the PHEV still has an internal combustion engine and other related components, there is no mass reduction). α is set to 111, taking into account that 111kWh of electricity is required to produce 1kWh of battery capacity. Therefore, in the model development of this embodiment, the coefficient is set to 50.

[0033] Step 2: Calculate CO2 emissions related to vehicle use, fuel production and combustion-related emissions to obtain carbon emissions data;

[0034] Specifically, we consider the calculation of CO2 emissions related to vehicle use, which include emissions from the combustion process and fuel production (ICE, HEV, PHEV) or emissions related to the production of electricity used to charge BEVs. The emissions related to the production and combustion of fuel (expressed in tons of CO2), in our case study gasoline (considering only production from fossil fuels) have been calculated according to formula (2), as a function of fuel consumption (expressed in kWh / 100 km, the energy density of gasoline is considered to be 8.6 kWh / liter), and D represents the distance traveled.

[0035] The emission calculation formula related to fuel production and combustion is:

[0036] CO2ICEusage=CO2Combustion*Fuel prod factor=(23.388.6*106*Energyconsumption ICE)*1.1236*D (2)

[0037] Where CO2ICEusage is the carbon emission of the ICE engine, D is the driving distance, and CO2Combustion is the carbon emission during the combustion process.

[0038] Regarding BEV, the total CO2 emissions associated with power generation, transportation and distribution, and charging are calculated by formula (3), (in this embodiment, ηAC_Heat is equal to 1.1, ηcharging is 1.15, ηprod is 0.93, and ηnetwork is 0.95).

[0039] The calculation formula for the emissions associated with the electricity production of battery electric vehicle charging is:

[0040] CO2BEVusage=ηAC_Heat*ηcharging / (ηprod*ηnetwork*105)*EnergyconsumptionBEV*fusage*D (3)

[0041] Where CO2BEVusage is the carbon emissions from the use of battery electric vehicles, ηAC_Heat is equal to 1.1, ηcharging is 1.15, ηprod is 0.93, and ηnetwork is 0.95.

[0042] By combining equations (2) and (3), the difference in vehicle usage emissions between the ICE baseline and the alternative powertrain under analysis can be obtained, as shown in equation (4):

[0043] The calculation formula for the carbon emission difference is:

[0045]

[0046] In the formula, δ1 and δ2 represent the relative increase coefficient of energy consumption of plug-in hybrid electric vehicle PHEV in pure fuel and pure electric modes compared with pure electric vehicle BEV, the energy consumption ratio γ of BEV is 3, UF is the charging facility coefficient, and f usage The maximum carbon intensity of the network for charging electric vehicles.

[0047] Considering the superior energy efficiency of BEVs relative to ICE vehicles, it can be assumed that the energy consumption per kilometer of a PHEV powered by an ICE engine is approximately three times that of a BEV. For a full HEV vehicle, this ratio is assumed to be 2. The coefficients δ1 and δ2 represent the relative increase in energy consumption of a PHEV compared to a BEV in pure fuel and pure electric modes, respectively. Therefore, the emission difference of a BEV or HEV vehicle compared to an equivalent ICE baseline can be calculated using equation (4), with an energy consumption ratio γ of 3 for BEVs and 2 for HEVs.

[0048] Step 3: Compare the carbon emission data with the baseline to obtain the carbon emission difference.

[0049] Specifically, PHEV calculations require a more detailed analysis, as an additional parameter needs to be taken into account: the charging facility factor (UF), which represents the number of kilometers driven in electric mode (charge depletion mode) divided by the total number of kilometers driven.

[0050] The CO2 emissions over the entire life cycle can then be calculated by combining equations (1) and (4). Since ΔCO2_Prod is positive for any electrification variant due to the emissions associated with energy consumption during battery production, the condition for obtaining a break-even (regardless of mileage) is that ΔCO2_usage is strictly negative (i.e. the alternative power solution produces less emissions than the ICE baseline during the use phase). Therefore, a limit value for f_usage can be determined that represents the maximum carbon intensity of the network used to charge electric vehicles that will still lead to reduced CO2 emissions at some point in the LCA life cycle. The fuel production and combustion-related emissions include emissions from the combustion process and fuel production, and emissions associated with the production of electricity used to charge battery electric vehicles.

[0051] Specifically, the application formula of the charging facility coefficient UF is:

[0052]

[0053] The variation of f_usage_limit based on PHEV and BEV applications, as well as the application of the charging facility factor UF limited to PHEVs, is shown in formula (5). The parameters of the nominal case have been considered and a sensitivity analysis for BEVs is indicated, showing that the limit version drops from 0.92 (the ideal case is defined as no additional heating and AC energy required, no charging losses, and no losses between power generation and distribution) to 0.45. Logically, the PHEV f_usage_limit decreases with increasing UF, as it relies more on electricity. At UF = 1 (i.e. pure electric drive), PHEVs logically require a cleaner source of electricity than BEVs to break even, as their energy efficiency deteriorates due to the additional mass of mechanical elements (internal combustion engine, gearbox, etc.). However, PHEVs have a lower production CO2 balance (lower capacity batteries) that needs to be compensated, and can also be charged at a slower rate, thereby minimizing charging losses.

[0054] If the electricity used is produced with a carbon intensity above the limit, then CO2 breakeven will never be achieved compared to an equivalent ICE vehicle because ΔCO2_usage is positive or equal to zero (then the deficit in CO2 production will never balance). That is, under nominal conditions, a BEV will emit less CO2 when in use than an ICE vehicle only if the carbon intensity of the electricity used for charging is below 640 g CO2 / kWh.

[0055] This example provides a simplified tool for analyzing the CO2 emissions of the powertrain structure of vehicle electrification and its impact on various powertrain alternatives. Although it does not yet include the impact of possible changes in the carbon intensity of electricity used during the life of the vehicle, it is still a very effective tool that is easy to use and compare.

[0056] At the same time, this embodiment enables feasibility analysis of the electrification of large rental or dispatch vehicle fleets to address various future options for power generation.

[0057] At the same time, the study of this embodiment clearly shows that the embodiment tool uses sufficient quantity and power of low-carbon intensity electricity, and proposes the contribution to carbon emissions from fleet electrification, and analyzes the quantitative limitations and the need for sufficient drivable electricity.

[0058] In summary, the present invention compiles a coefficient based on the carbon emissions of traditional ICE engines as a baseline, and the coefficient represents the change in carbon emission intensity during the battery production process; calculates CO2 emissions related to vehicle use, fuel production and combustion-related emissions to obtain carbon emission data; compares the carbon emission data with the baseline to obtain carbon emission differences to compare the carbon emission footprints of various powertrains, as well as their carbon emissions at incremental electrification levels of various light vehicles, so that relevant parameters can be selected for vehicle production and use, and a simplified tool for analyzing the carbon emission levels and impacts of the power structure of vehicle electrification is provided for various powertrain alternatives, which is easy to use and compare.

[0059] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for estimating carbon dioxide emissions during vehicle electrification, characterized in that: include: A coefficient is compiled based on the carbon emissions of traditional ICE engines, which represents the change in carbon emission intensity during battery production; Calculate CO2 emissions related to vehicle use, fuel production and combustion related emissions to obtain carbon emissions data; The carbon emission data is compared with a baseline to obtain a carbon emission difference.

2. The method for estimating carbon dioxide emissions during vehicle electrification according to claim 1, characterized in that: The fuel production and combustion-related emissions include emissions from the combustion process and fuel production, and emissions related to the production of electricity used to charge battery electric vehicles.

3. The method for estimating carbon dioxide emissions during vehicle electrification according to claim 2, characterized in that: The coefficient is CBatt*fprod, The formula is: ΔCO2Prod = α*β*(CBatt*fprod); Where α is the energy ratio required to produce 1 kWh of battery, CBatt*fprod is the carbon intensity of the battery production process, and β is the sedimentation coefficient used to reflect the reduction in vehicle mass associated with the removal of the engine and other components.

4. The method for estimating carbon dioxide emissions during vehicle electrification according to claim 3, characterized in that: The emission calculation formula related to fuel production and combustion is: CO2ICEusage=CO2Combustion*Fuel prod factor=(23.388.6*106*Energyconsumption ICE)*1.1236*D; Where CO2ICEusage is the carbon emission of the ICE engine, D is the driving distance, and CO2Combustion is the carbon emission during the combustion process.

5. The method for estimating carbon dioxide emissions during vehicle electrification according to claim 4, characterized in that: The calculation formula for the emissions associated with the electricity production of battery electric vehicle charging is: CO2BEVusage=ηAC_Heat*ηcharging / (ηprod*ηnetwork*105)*EnergyconsumptionBEV*fusage*D; Where CO2BEVusage is the carbon emissions from the use of battery electric vehicles, ηAC_Heat is equal to 1.1, ηcharging is 1.15, ηprod is 0.93, and ηnetwork is 0.

95.

6. The method for estimating carbon dioxide emissions during vehicle electrification according to claim 5, characterized in that: The calculation formula for the carbon emission difference is: In the formula, δ1 and δ2 represent the relative increase coefficient of energy consumption of plug-in hybrid electric vehicle PHEV in pure fuel and pure electric modes compared with pure electric vehicle BEV, the energy consumption ratio γ of BEV is 3, UF is the charging facility coefficient, and f usage The maximum carbon intensity of the network for charging electric vehicles.

7. The method for estimating carbon dioxide emissions during vehicle electrification according to claim 6, characterized in that: The application formula of the charging facility coefficient UF is:

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