Modeling and Analysis of Carbon Emissions Throughout Lifecycle of Electric Vehicles Considering Dynamic Carbon Emission Factors

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

-The authors proposed a a dynamic carbon emission assessment model that  incorporates a source-load synergistic optimization mechanism, accounting for unit commitment status, generation unit output characteristics, wind power integration constraints, and the flexible load profiles of EV charging and discharging, to
 enable the dynamic tracking of carbon flow distribution across the generation,
transmission (grid), and consumption (load) segments of the power system.

The following points have to be considered:

1- The equations describing Carbon Emission Model for the Production Phase have to be justified or referenced

2-Using wind energy as a power source is not clearly described. Do you mean it is the only power source for charging the EV batteries?  Please clarify the role of wind energy whether it is the only power source or grid integrated.

3-Since wind energy employment will affect carbon emissions, the wind energy generation strategy must be defined.

4. Equations accounting for Grid Power Purchase Constraints, Line Power Flow Constraints:, Power Transfer Distribution Factor) Constraints, Nodal Power Balance Constraints, Generator Ramping Constraints, and EV Charging/Discharging State of Charge (SOC) Constraints must be referenced or justified.

5-Fig. 9 describing Carbon potential distribution of IEEE33 node needs clarification since the colors are not distinguished

6- The authors claimed that their presented study introduces a novel source-load synergistic optimization approach. Objective function was proposed. However, in order to prove that the given approach optimizes, or precisely, decreases carbon emissions throughout the different EV phases ( EV production, recycling, operation,...etc), a comparison has to be done between the results obtained from this proposed  algorithm and previous methods that concerns minimizing EV carbon emissions. Otherwise, this paper results are confined to carbon emission calculations without optimization. Please clarify your contribution.

Comments on the Quality of English Language

The authors must clarify and justify some points before accepting the paper.

Author Response

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Author Response File: Author Response.docx

Reviewer 2 Report

Comments and Suggestions for Authors

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Comments for author File: Comments.pdf

Author Response

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Author Response File: Author Response.docx

Reviewer 3 Report

Comments and Suggestions for Authors

The study investigated the carbon emission of electric vehicle throughout the life cycle assessments. However, there are several problems which need be revised and further addressed.

 

• Line number should be added for the review works
• From the figure 1, there are 4 phases for the life cycle, but in the main text, the life cycle was segmented into three distinct phases.
• For the methodology of LCA, the accuracy and reliable inventory data should be the primary part for the results. Please supplement the other data related to the EV, rather than the materials proportion inventory.
• For the figure 3, what is meaning about the black points, such as the node 3, 5, 6, 7 and so forth. Cite the reference for the IEEE 33-bus distribution test.
• Figure 4, explain the abbreviations for the x-axis.
• Supplement the assumptions in the research, otherwise, the obtained results are not useful in the practical case. 

Author Response

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Author Response File: Author Response.docx

Reviewer 4 Report

Comments and Suggestions for Authors

This study presents a dynamic life-cycle carbon emission assessment model for electric vehicles (EVs), incorporating time-variant carbon emission factors and source-load synergistic optimization. The research addresses a critical gap in existing literature by systematically analyzing operational-phase emissions through dynamic nodal carbon intensity tracking. The methodology is comprehensive, and the results highlight the dominance of operational-phase emissions (75.1% under V2G) in total lifecycle emissions, offering actionable insights for decarbonizing EV integration. The paper is well-structured and contributes meaningfully to the field of sustainable transportation. However, certain aspects require clarification or improvement to enhance rigor and readability.
1.Figure 1 (lifecycle phases) is referenced in the text but not included in the manuscript. Ensure all figures are provided.
2.Table 1 lists material mass proportions but does not specify whether these values are derived from literature or original data. Clarify the source.
3.Typos: “V2G” is undefined at first mention (Abstract); “GREET model” in Section 1 requires expansion.
4.The dominance of operational-phase emissions aligns with prior studies (e.g., [Tagliaferri et al., 2016]). Emphasizing how the dynamic model improves upon static approaches (e.g., quantifying spatiotemporal heterogeneity) would better highlight the novelty.
5.The 46.9% reduction in Scenario 4 is impressive but should be contextualized with real-world V2G adoption barriers (e.g., infrastructure costs, user acceptance).
6.Reference formatting is inconsistent (e.g., [1] uses full author names, while others use initials). Ensure adherence to journal guidelines.
7.Some references (e.g., [12], [14]) are listed as “1–15[2025-02-20]” or “1–8,” suggesting incomplete details. Verify completeness.

Comments on the Quality of English Language

The English could be improved to more clearly express the research.

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The authors have  justified and referenced the equations describing Carbon Emission Model for the Production Phase.

A detailed explanation for wind energy generation strategy was added.

The required citations are added.

The clarity of fig. 9 has been improved.

The authors did not compare the results of their optimization  with previous literature results. However they analyzed the results satisfactorily.