Calculation method for greenhouse gas emission reduction of electric container ship

Abstract

The invention relates to the field of electric ship emission reduction calculation, in particular to an electric container ship greenhouse gas emission reduction calculation method which comprises the following steps: S1, according to a to-be-researched electric container ship, determining a datum line container ship and collecting data; s2, for the target ship and the datum line container ship, calculating the cargo turnover and the weighted average load rate of each going voyage number; s3, fitting the weighted average load rate and the unit discharge capacity of the target ship and each datum line container ship to obtain a fitting equation; s4, calculating a unit emission characterization value and a reference line value according to the fitting equation; and S5, the emission reduction amount and the emission reduction proportion of the target ship are calculated according to the unit emission characterization value of the target ship and the reference line value. According to the method, the problem of quantitative calculation of greenhouse gas emission reduction in the transportation activity of the electric container ship is solved by setting the datum line container ship, calculating the datum line value by using the fitting algorithm and using the weighted average load rate.

Description

Technical Field

[0001] The present invention relates to the field of electric ship emission reduction calculation, and in particular to a method for calculating greenhouse gas emission reduction of an electric container ship. Background Art

[0002] Currently, greenhouse gas emissions accounting in the shipping industry primarily focuses on the emissions from the use of fossil fuels during the shipping process of conventional fuel container ships. Given the complexity of the life cycle, common emissions accounting primarily quantifies the use of fossil fuels. This process uses an emission factor method: emissions = activity level data * emission factor * GWP. However, the shipping industry's emission reduction quantification relies solely on the following formula: project emissions reduction = project baseline emissions - project activity emissions. Due to the current limited operation of electric container ships in the shipping industry, a quantitative calculation method for electric container ships is still lacking. Summary of the Invention

[0003] In order to solve the problem of lack of quantitative calculation of greenhouse gas emission reduction of electric container ships, the present invention proposes a calculation method of greenhouse gas emission reduction of electric container ships, which can well solve the problem of quantitative calculation of greenhouse gas emission reduction in electric container ship transportation activities.

[0004] The technical solution of the present invention is:

[0005] A method for calculating greenhouse gas emission reductions of electric container ships, comprising:

[0006] S1. Determine a baseline container ship and collect data based on the electric container ship to be studied: determine an electric container ship to be studied as the target ship, and use the unit emissions of its transportation activities as the target ship emissions. The baseline container ship is one or more traditional fuel container ships with the same route as the target ship and similar designed TEU loading capacity. The average unit emissions of the baseline container ship's transportation activities are the baseline emissions; similar designed TEU loading capacity means that the designed TEU loading of the baseline container ship is within ±50% of the designed TEU loading of the target ship.

[0007] The designed deadweight tonnage may be used instead of the designed TEU load capacity, with the load capacity calculated in tons. Tons are then used as the unit of measurement for the actual transported cargo. If the actual mass of the containerized cargo is unavailable, when tons are used as the unit of measurement for the actual transported cargo, one loaded TEU is converted to 10 tons, and one empty TEU is converted to 2 tons.

[0008] Collecting data on the designed TEU loading capacity, route distance, and outbound voyage transportation during the empirical study period for the target vessel and the baseline container ship, respectively; the outbound voyage transportation data includes: actual cargo transportation volume, actual cargo transportation distance, power consumption of the target vessel, fossil energy consumption of the target vessel, and fossil energy consumption of the baseline container ship;

[0009] S2, calculating the cargo turnover of each outbound voyage for the target vessel and the baseline container ship based on the data collected in S1, wherein the unit of the cargo turnover is TEU km, that is, the cargo turnover is the carrying capacity in the uniform volume unit of a container multiplied by the transportation distance;

[0010] S21, calculating the cargo turnover of each outbound voyage based on the actual cargo transportation volume and the actual cargo transportation distance:

[0011] Cargo turnover = ∑(actual cargo transportation volume × actual cargo transportation distance);

[0012] S22, calculating the weighted average load factor of each outbound voyage according to the cargo turnover, the designed TEU loading capacity, and the route distance;

[0013] Weighted average load factor = cargo turnover / (designed TEU loading capacity × route distance);

[0014] S23, calculating the greenhouse gas emissions of each of the outbound voyage target ships and the baseline container ship based on the electricity consumption, the fossil energy consumption, and the cargo turnover according to the relevant emission coefficients published by the competent authorities:

[0015] Greenhouse gas emissions = energy consumption × energy emission coefficient

[0016] The energy sources of the target ship are electricity and fossil energy, and the energy source of the baseline container ship is fossil energy.

[0017] S24, calculating the greenhouse gas emissions per unit turnover of each outbound voyage based on the greenhouse gas emissions and the cargo turnover, that is, the unit emissions:

[0018] Unit emissions = greenhouse gas emissions / cargo turnover;

[0019] S3, performing linear fitting on the weighted average load factor and the unit emission of the target ship and each of the baseline container ships, respectively, and removing data with obvious deviations, to obtain fitting equations for the target ship and each of the baseline container ships, respectively;

[0020] S4, calculating the unit emission when the weighted average load factor is 75% according to the fitting equation of the target ship as the unit emission representative value of the target ship;

[0021] Calculate the unit emissions when the weighted average load factor is 75% according to the fitting equation of each baseline container ship, and use them as the unit emissions representation value of each baseline container ship;

[0022] Calculate the average of the unit emission characteristic values of each of the baseline container ships as the baseline value;

[0023] S5, obtaining the unit emission reduction of the target ship by calculating the difference between the unit emission characterization value of the target ship and the baseline value; calculating the unit emission reduction ratio of the target ship by calculating the ratio of the unit emission characterization value of the target ship to the baseline value.

[0024] The calculation formula for the target ship's unit emission reduction is:

[0025] Target ship unit emission reduction = target ship unit emission characteristic value - baseline value

[0026] The calculation formula for the target ship unit emission reduction ratio is:

[0027] Unit emission reduction ratio of the target ship = 1-(unit emission characteristic value of the target ship / baseline value).

[0028] The present invention proposes a method for calculating the greenhouse gas emission reduction of electric container ships. By comparing the emissions of electric container ships with the baseline values based on the emissions of traditional fuel container ships, the greenhouse gas emission reduction and emission reduction ratio of electric container ships in transportation activities compared with traditional fuel container ships are quantitatively calculated. Specifically, one or more traditional fuel container ships with the same voyage as the electric container ship serving as the target ship and similar designed TEU loading capacity are selected as baseline container ships, and a weighted average load rate is used that takes into account both the ratio of the number of cargo TEUs loaded in the voyage to the designed TEU loading capacity and the cargo carrying distance, and the unit emissions of the target ship and the baseline container ship are quantitatively calculated at the same time; then, the weighted average load rate and unit emissions of each of the target ship and the baseline container ship are fitted respectively to obtain a fitting equation, and the emission characterization value is obtained in combination with the average load rate in practice; the emission characterization values of multiple baseline container ships are averaged as the baseline value, and the baseline value is excluded. The impact of the differences between electric container ships is taken into account, and the emission reduction of the target ship is then calculated. That is, when determining the baseline emission value of the project, the present invention does not simply use the aggregated average of traditional fuel container ships as a reference, but is based on the fitting equation of one or more traditional fuel container ships, combined with the average load rate in practice, and the emission values under the average load rate are obtained in turn as unit emission characterization values, and averaged to obtain the baseline value. In this way, although the main factors considered in the calculation of the emission reduction of electric container ships are the container loading capacity and carrying distance, rather than all influencing parameters, the emission reduction of electric container ships relative to traditional fuel container ships can be well calculated through the above method. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 The figure is a flow chart of a method for calculating greenhouse gas emission reductions of electric container ships.

[0030] Figure 2 It is the fitted trend line of the weighted average load factor-unit emission of the baseline container ship A.

[0031] Figure 3 The fitted trend line of the weighted average load factor-specific emission of baseline container ship B.

[0032] Figure 4 is the fitted trend line of the weighted average load factor-specific emission of the baseline container ship C.

[0033] Figure 5 The fitted trend line is the weighted average load factor-specific emission of the target ship. DETAILED DESCRIPTION

[0034] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0035] A calculation method for greenhouse gas emission reduction of electric container ships, the flow chart is as follows Figure 1 Shown, including:

[0036] S1. Determine a baseline container ship and collect data based on the electric container ship to be studied: determine an electric container ship to be studied as the target ship, and the unit emissions of its transportation activities are used as the target ship emissions. The baseline container ship is one or more traditional fuel container ships with the same route and similar designed TEU loading capacity as the target ship. The average unit emissions of the transportation activities of the baseline container ship are the baseline emissions; collect data on the designed TEU loading capacity, route distance, and transportation process of the target ship and the baseline container ship during the outbound voyage within the empirical research period.

[0037] The optimal baseline containership is a conventionally fueled containership with the same routes and design parameters as the benchmark vessel. However, since conventionally fueled containerships with exactly the same routes and design parameters as the benchmark vessel do not exist in reality, the baseline containership selection criteria are set to be conventionally fueled containerships with the same routes and similar design TEU capacity as the benchmark vessel. Similar design TEU capacity means that the baseline containership's design TEU capacity is within ±50% of the benchmark vessel's design TEU capacity.

[0038] In actual transportation, the statistical unit of transportation volume is mainly TEU, so the designed TEU loading capacity is selected in this embodiment, and the actual transportation volume of goods is also counted in TEU.

[0039] In this example, the target ship's design TEU capacity is 654. Based on the baseline container ship selection criteria, three conventional fuel container ships were selected as baseline container ships, named A, B, and C. The baseline container ship information is shown in Table 1:

[0040] Table 1 Baseline container ship information

[0041]

[0042] The data during the transportation process of the outbound voyage includes: the actual transportation volume of goods, the actual transportation distance of goods, the power consumption of the target ship, and the fossil energy consumption of the baseline container ship.

[0043] Alternatively, the designed deadweight tonnage can be used instead of the designed TEU loading capacity, with the loading capacity calculated in tons, while using tons as the unit of measurement for the actual cargo transported. Referring to the "Regulations on the Management of Ship Energy Consumption Data and Carbon Intensity," if the actual mass of containerized cargo is unavailable, a laden TEU can be converted to 10 tons and an empty TEU to 2 tons to determine the load capacity.

[0044] When calculating the target vessel's energy consumption, energy consumption during transport and shore power at berth is taken into account. For the target vessel, both electricity consumption and fuel consumption from standby engines in special circumstances are considered; for the baseline container ship, only fossil fuel consumption is considered.

[0045] S2. Calculate the cargo turnover of each of the outbound voyages for the target ship and the baseline container ship respectively based on the data collected in S1. The unit of the cargo turnover is TEU km, that is, the cargo turnover is the carrying capacity in the uniform volume unit of containers multiplied by the transportation distance; calculate the weighted average load factor of each of the outbound voyages based on the cargo turnover, the designed TEU loading capacity, and the route distance; calculate the unit emissions of each of the outbound voyages based on the electricity consumption, the fossil energy consumption, and the cargo turnover.

[0046] For cargo loading, it is necessary to consider not only the ratio of the number of cargo TEUs loaded on the voyage to the designed TEU loading capacity, but also the distance the cargo is transported. This is because cargo is not always loaded at the port of departure but may be loaded at other ports along the route, which will result in different cargo transportation distances and, in turn, changes in emissions.

[0047] Specifically, S21, calculating the cargo turnover of each outbound voyage according to the actual cargo transportation volume and the actual cargo transportation distance:

[0048] Cargo turnover = ∑(actual cargo transportation volume × actual cargo transportation distance);

[0049] S22: Calculate the weighted average load factor of each outbound voyage based on the cargo turnover, the designed TEU loading capacity, and the route distance:

[0050] Weighted average load factor = cargo turnover / (designed TEU loading capacity × route distance);

[0051] According to the electricity consumption, the fossil energy consumption and the cargo turnover, the unit emissions of each of the outbound voyage target ships and the baseline container ship are calculated respectively according to the relevant emission coefficients published by the competent authorities.

[0052] S23, calculating the greenhouse gas emissions of each outbound voyage using the emission coefficient method based on the power consumption of the target ship and the fossil energy consumption of the baseline container ship:

[0053] Greenhouse gas emissions = energy consumption × energy emission coefficient

[0054] The energy source of the target ship is electricity, and the energy source of the baseline container ship is fossil energy.

[0055] The emission coefficient refers to the coefficient for converting activity level data into greenhouse gas emissions, that is, the emission value per unit activity. In this embodiment, because the emissions of other greenhouse gases are significantly less than the emissions of carbon dioxide, only the emissions of carbon dioxide are used as greenhouse gas emissions.

[0056] When calculating emissions from baseline container ships, only emissions from fossil fuel use are accounted for; full-lifecycle emissions from fossil fuels are not considered. The emission coefficient used in diesel fuel consumption calculations refers to the parameters used in the documents published by the competent authority, namely the carbon emission coefficient of 3.206tCO2 / t in the "Guidelines for the Calculation and Verification of the Energy Efficiency Design Index (EEDI) for Inland Vessels" (2022). This figure is based on the calorific value of diesel and the carbon content per unit of calorific value.

[0057] When calculating the target vessel's emissions, because data on carbon emissions from electricity consumption by electric container ships is currently unavailable, this example uses the average CO2 emission factor for electricity published by the competent authorities, which measures the amount of CO2 generated per unit of power generated by the grid. The target vessel in this example routes through East China, so the published data for that region, 0.5617 kgCO2 / MWh, is used.

[0058] S24, calculating the greenhouse gas emissions per unit turnover of each outbound voyage based on the greenhouse gas emissions and the cargo turnover, that is, the unit emissions:

[0059] Unit emissions = greenhouse gas emissions / cargo turnover.

[0060] According to international and domestic shipping industry regulations, unit emissions are usually used to measure the carbon emissions of ships.

[0061] In this embodiment, the unit emissions of each outbound voyage of the target ship and the baseline container ship A are shown in Tables 2 and 3.

[0062] Table 2 Specific emissions of target vessels on each outbound voyage

[0063]

[0064] Table 3 Specific emissions of baseline container ship A on each outbound voyage

[0065]

[0066]

[0067] S3. Fitting the weighted average load factor and the unit emission of the target ship and each of the baseline container ships, respectively, and removing data with obvious deviations to obtain fitting trend lines and equations for the target ship and each of the baseline container ships.

[0068] The calculated voyage-specific emissions data show significant fluctuations in unit emissions between voyages. The factors contributing to this can be broadly categorized as follows:

[0069] (1) External environment. The water flow rate and external environmental conditions at different time periods result in different energy demands.

[0070] (2) Operational status. Cargo may come from multiple ports during different voyages, and the large number of ports of call brings additional energy demand related to berthing. In addition, the berthing time is subject to port scheduling and cannot be maintained uniformly. The longer the berthing time, the greater the energy consumption required.

[0071] (3) Cargo situation. The amount of cargo loaded on each voyage varies, and it cannot reach 100% full load, resulting in different operating efficiency, which in turn affects energy consumption. At the same time, ship transportation is measured in TEUs, and the difference in the actual weight of the cargo will affect the energy consumption of each voyage.

[0072] In this embodiment, only the relationship between the single factor of cargo load and unit emissions is studied, and a correlation analysis is carried out. A quantitative relationship between unit emissions and the weighted average load rate is established through linear fitting.

[0073] Taking the baseline container ship A as an example, the weighted average load factor of each voyage is used as the horizontal axis, and the unit emission of the voyage is used as the vertical axis to plot the data points of the voyage in the figure. After eliminating the data with obvious deviations, we get Figure 2 Then perform linear fitting on the data that are not eliminated and obtain the following Figure 2 The fitted trend line is shown.

[0074] The same method is used to perform linear fitting on the baseline container ships B and C, and the following results are obtained: Figure 3 、 Figure 4 The fitted trend line is shown in the figure. The same method is used to perform linear fitting on the target ship to obtain the following Figure 5 The fitted trend line is shown.

[0075] In this embodiment, the target ship's operating time is short, resulting in a small amount of data, so the data with obvious deviations are not eliminated; and the weighted average load rate of most voyages is low, resulting in large data deviations, which have a certain impact on the fitting results.

[0076] S4. Calculate the unit emissions when the weighted average load factor is 75% based on the fitted trend lines and equations of the target ship and each of the baseline container ships, as the unit emission characterization values of the target ship and each of the baseline container ships.

[0077] From the fitting results, it can be seen that the unit emissions and the weighted average load rate show an obvious linear correlation, indicating that the weighted average load rate has a significant impact on the carbon emissions of ships. Therefore, it is necessary to determine a weighted average load rate close to the actual situation to calculate the emission reduction of electric container ships. In this embodiment, based on the data of the baseline container ship and the actual operation of existing traditional fuel container ships, a weighted average load rate of more than 70% is a relatively common operating state; at the same time, referring to the load rate data of European inland container ships in the "Global Logistics Emissions Council Logistics Emissions Accounting and Reporting Framework V3.1", after comprehensive consideration, the target value of the weighted average load rate in this embodiment is set to 75%, and the unit emissions at this time are used as the unit emission characterization value of the container ship.

[0078] In this embodiment, the calculation results of the fitting equation and the characterization value are shown in Table 4.

[0079] Table 4 Fitting equations and characterization values of the target ship and the baseline container ship

[0080] Characterization value Fitting equation <![CDATA[R 2 ]]> gCO2 / (TEU·km) / / Target ship 66.00 y=-129.3x+162.97 0.5337 A 98.71 y=-183.32x+236.2 0.8497 B 64.63 y=-166.26x+189.32 0.8726 C 93.44 y=-370.29x+371.16 0.8904

[0081] In order to avoid the influence of individual differences among the baseline container ships, the average value of the unit emission characteristic values of each baseline container ship is calculated as the baseline value.

[0082] In this embodiment, the average value of the unit emission characteristic values of three baseline container ships is used as the baseline value, and the baseline value is 85.59 gCO2 / (TEU·km).

[0083] S5, calculating the difference between the target ship's unit emission characteristic value and the baseline value to obtain the target ship's unit emission reduction:

[0084] Target ship unit emission reduction = target ship unit emission characteristic value - baseline value

[0085] The unit emission reduction ratio of the target ship is calculated by calculating the ratio of the target ship's unit emission characteristic value to the baseline value:

[0086] Unit emission reduction ratio of the target ship = 1-(unit emission characteristic value of the target ship / baseline value).

[0087] In this example, the target vessel's unit emissions reduction is 19.59gCO2 / (TEU·km). This means that compared to a conventional fuel container ship operating the same route and with a similar designed TEU load, using the target vessel for cargo transportation, at the same load factor, can reduce CO2 emissions by 19.59gCO2 per TEU·km. This represents a 23% reduction in unit emissions.

[0088] It should be noted that the specific embodiments described above can enable those skilled in the art to more fully understand the present invention, but do not limit the present invention in any way. Therefore, although this specification has described the present invention in detail with reference to the drawings and embodiments, those skilled in the art should understand that the present invention can still be modified or replaced with equivalents. In short, all technical solutions and improvements that do not depart from the spirit and scope of the present invention should be included in the scope of protection of the patent for the present invention.

Claims

1. A method for calculating greenhouse gas emission reductions of electric container ships, characterized in that: include: S1. Determine a baseline container ship based on the electric container ship to be studied and collect data: Determine an electric container ship to be studied as the target ship, and use the unit emissions of its transportation activities as the target ship emissions. The baseline container ship is one or more traditional fuel container ships with the same route and similar designed TEU loading capacity as the target ship. The average unit emissions of the baseline container ship's transportation activities are the baseline emissions. Collect data on the designed TEU loading capacity, route distance, and transportation process of the target ship and the baseline container ship during the empirical study period; The data during the outbound voyage transportation process includes: actual cargo transportation volume, actual cargo transportation distance, power consumption of the target ship, fossil energy consumption of the target ship, and fossil energy consumption of the baseline container ship; S2, calculating the cargo turnover of each outbound voyage for the target vessel and the baseline container ship based on the data collected in S1, wherein the unit of the cargo turnover is TEU km, that is, the cargo turnover is the carrying capacity in the uniform volume unit of a container multiplied by the transportation distance; The weighted average load factor of each outbound voyage is calculated based on the cargo turnover, the designed TEU loading capacity, and the route distance: Weighted average load factor = cargo turnover / (designed TEU loading capacity × route distance); Calculate the unit emissions of each of the outbound voyage target ships and the baseline container ship based on the electricity consumption, the fossil energy consumption and the cargo turnover according to the relevant emission coefficients published by the competent authorities; S3, fitting the weighted average load factor and the unit emission of the target ship and each of the baseline container ships, respectively, to obtain fitting equations for the target ship and each of the baseline container ships; S4, calculating the unit emission when the weighted average load factor is 75% according to the fitting equation of the target ship as the unit emission representative value of the target ship; Calculate the unit emissions when the weighted average load factor is 75% according to the fitting equation of each baseline container ship, and use them as the unit emissions representation value of each baseline container ship; Calculate the average of the unit emission characteristic values of each of the baseline container ships as the baseline value; S5, obtaining the unit emission reduction of the target ship by calculating the difference between the unit emission characterization value of the target ship and the baseline value; calculating the unit emission reduction ratio of the target ship by calculating the ratio of the unit emission characterization value of the target ship to the baseline value.

2. The method for calculating greenhouse gas emission reduction of an electric container ship according to claim 1, characterized in that: The similarity in designed TEU loading capacity means that the designed TEU loading capacity of the baseline container ship is within a range of ±50% of the designed TEU loading capacity of the target ship.

3. The method for calculating greenhouse gas emission reduction of an electric container ship according to claim 1, characterized in that: The S2 includes: S21, calculating the cargo turnover of each outbound voyage based on the actual cargo transportation volume and the actual cargo transportation distance: Cargo turnover = ∑(actual cargo transportation volume × actual cargo transportation distance); S22, calculating the weighted average load factor of each outbound voyage according to the cargo turnover, the designed TEU loading capacity, and the route distance; S23, calculating the greenhouse gas emissions of each outbound voyage using an emission coefficient method based on the power consumption of the target ship, the fossil energy consumption of the target ship, and the fossil energy consumption of the baseline container ship: Greenhouse gas emissions = energy consumption × energy emission coefficient The energy sources of the target ship are electricity and fossil energy, and the energy source of the baseline container ship is fossil energy. S24, calculating the greenhouse gas emissions per unit turnover of each outbound voyage based on the greenhouse gas emissions and the cargo turnover, that is, the unit emissions: Unit emissions = greenhouse gas emissions / cargo turnover.

4. The method for calculating greenhouse gas emission reduction of an electric container ship according to claim 1, characterized in that: The designed deadweight tons can be used instead of the designed TEU loading capacity, and the loading capacity can be calculated in tons, while tons are used as the unit of measurement for the actual transport volume of the goods.

5. The method for calculating greenhouse gas emission reduction of an electric container ship according to claim 4, characterized in that: When the actual mass of the containerized cargo is unavailable and tons are used as the unit of measurement for the actual transport volume of the cargo, one loaded standard container is converted to 10 tons and one empty standard container is converted to 2 tons.

6. The method for calculating greenhouse gas emission reduction of an electric container ship according to claim 1, characterized in that: In S3, the fitting is a linear fitting.

7. The method for calculating greenhouse gas emission reduction of an electric container ship according to claim 1, characterized in that: In S3, data with obvious deviations are removed.

8. The method for calculating greenhouse gas emission reduction of an electric container ship according to claim 1, characterized in that: The calculation formula for the target ship's unit emission reduction is: Target ship unit emission reduction = target ship unit emission characteristic value - baseline value The calculation formula for the target ship unit emission reduction ratio is: Unit emission reduction ratio of the target ship = 1-(unit emission characteristic value of the target ship / baseline value).

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