Review Reports - Integrating Remote Sensing and Geospatial-Based Comprehensive Multi-Criteria Decision Analysis Approach for Sustainable Coastal Solar Site Selection in Southern India

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This manuscript proposes a structured integration of a decision-making model with Geographic Information Systems (GIS) to assess sustainability indicators for solar farm site selection in the coastal region of Thoothukudi, India. The findings of this potential paper could offer insights for decision-makers. However, there are a few areas that require clarification and some modifications that need to be made before the manuscript can be considered for publication.

The reviewer notes a key concern regarding the omission of Socioeconomic and Regulatory Indicators in the site selection framework, particularly given that the manuscript’s title emphasizes “Sustainable Coastal Solar Site Selection.” It is recommended that the authors clarify whether these dimensions were considered, and if excluded, provide a rationale for their omission in light of the sustainability scope.
A key point of clarification concerns the apparent geographic specificity of the proposed model, which seems to be designed solely for application in the coastal city of Thoothukudi. If this is the case, the manuscript may be more appropriately categorized as a case study. Otherwise, it is recommended that the authors clearly explain how the model can be calibrated or generalized for application in other coastal or non-coastal contexts, thereby enhancing its broader relevance.
The first specific objective of the study—namely, the integration of multiple parameters representing photovoltaic, climatic, topographic, environmental, and accessibility factors—would benefit from further elaboration with references to relevant prior research and authoritative sources. It is recommended that the authors clarify the rationale and methodology underlying the selection and treatment of these parameters within the proposed framework.
Another important issue relates to the implementation of the Pairwise Comparison process within the Analytic Hierarchy Process (AHP) methodology. If this evaluation was conducted by expert participants, it is recommended that the authors provide general information regarding the composition of the expert group, including their professional backgrounds, areas of expertise, and relevant experience.
To strengthen the academic rigor and transparency of the manuscript, it is recommended that the authors explicitly discuss the limitations of the research within the Conclusion section.

Minor comment:

The term “Analytical Hierarchy Process” appears to be repeated in the Keywords section.
Please revise the citation formatting by using brackets [ ] instead of parentheses ( ), following standard referencing guidelines.
Kindly revise the citation formatting for “Elkadeem et al., 2022; Gholami, 2024” to adopt the numerical referencing style, consistent with the format used throughout the manuscript.
On page 4, line 155, the sentence appears to be missing a concluding period.
It is recommended that the authors carefully review the manuscript to correct minor grammatical errors, such as missing commas. For instance, in the sentence “This coastal urban region lies along the coral reef ecosystems that are included within the Gulf of Mannar Biosphere Reserve shown in Figure 1,” a comma is required before “shown” to ensure clarity and syntactic precision.
Kindly provide the full form of the abbreviation “NTPL” upon its first occurrence in the manuscript.
For improved manuscript formatting and readability, please ensure that each figure is positioned immediately following the paragraph in which it is first cited.

Author Response

Response to Reviewer (1)

Comments and Suggestions for Authors:

Comment 1: The reviewer notes a key concern regarding the omission of Socioeconomic and Regulatory Indicators in the site selection framework, particularly given that the manuscript’s title emphasizes “Sustainable Coastal Solar Site Selection.” It is recommended that the authors clarify whether these dimensions were considered, and if excluded, provide a rationale for their omission in light of the sustainability scope.

Response: Thank you for this constructive feedback regarding sustainability indicators. Our study addresses sustainability through the SDG framework (SDG 7, 11, and 13) established in our introduction, focusing on technical and environmental sustainability as the essential foundation for comprehensive assessment. Page 23, Lines 788-790: Added new subsection 4.5.1 "Scope of Sustainability Assessment" explaining SDG-aligned framework and acknowledging current scope limitations. Page 24, Lines 848-860: Enhanced conclusion section to explicitly connect findings with SDG achievement potential. Page 23, Lines 790-795: Added future research recommendations for socioeconomic integration.

Comment 2: A key point of clarification concerns the apparent geographic specificity of the proposed model, which seems to be designed solely for application in the coastal city of Thoothukudi. If this is the case, the manuscript may be more appropriately categorized as a case study. Otherwise, it is recommended that the authors clearly explain how the model can be calibrated or generalized for application in other coastal or non-coastal contexts, thereby enhancing its broader relevance.

Response: Thank you for highlighting the need for a broader geographic context. Page 5-6, Lines 232-234: Enhanced Table 1 with comprehensive justifications and literature support. Page 5, Lines 200-205: Added systematic literature review mention and expert validation.

Comment 3: The first specific objective of the study—namely, the integration of multiple parameters representing photovoltaic, climatic, topographic, environmental, and accessibility factors—would benefit from further elaboration with references to relevant prior research and authoritative sources. It is recommended that the authors clarify the rationale and methodology underlying the selection and treatment of these parameters within the proposed framework.

Response: Thank you for highlighting the need for greater transparency in parameter selection. We have significantly expanded Table 1 with detailed justifications for each parameter, added comprehensive literature support ([23-53]) validating our choices, and enhanced Section 2.2 with detailed explanations of data preprocessing methods. The enhanced table now demonstrates how each parameter addresses specific coastal environment challenges with supporting citations.

Comment 4: Another important issue relates to the implementation of the Pairwise Comparison process within the Analytic Hierarchy Process (AHP) methodology. If this evaluation was conducted by expert participants, it is recommended that the authors provide general information regarding the composition of the expert group, including their professional backgrounds, areas of expertise, and relevant experience.

Response: Thank you for requesting transparency in our expert consultation process Page 8, Lines 270-273: Added expert panel composition details including academic specialists (3) from renewable energy systems and industry professionals (2) with coastal environmental expertise.

Comment 5: To strengthen the academic rigor and transparency of the manuscript, it is recommended that the authors explicitly discuss the limitations of the research within the Conclusion section..

Response: Thank you for this important suggestion to enhance academic rigor. Page 22, Lines 787-825: Added comprehensive Section 4.5 "Study Limitations".

Minor comments:

The term “Analytical Hierarchy Process” appears to be repeated in the Keywords section.

Response: Page 2, Line 49: Removed duplicate "Analytical Hierarchy Process" from Keywords section.

Please revise the citation formatting by using brackets [ ] instead of parentheses ( ), following standard referencing guidelines.

Response: Revised all citation formatting to use brackets [1] instead of parentheses throughout the manuscript.

Kindly revise the citation formatting for “Elkadeem et al., 2022; Gholami, 2024” to adopt the numerical referencing style, consistent with the format used throughout the manuscript.

Response: Converted author-date citations to numerical referencing style.

On page 4, line 155, the sentence appears to be missing a concluding period.

Response: Page 4, line 155: Added period to the temperature data now in line 177.

It is recommended that the authors carefully review the manuscript to correct minor grammatical errors, such as missing commas. For instance, in the sentence “This coastal urban region lies along the coral reef ecosystems that are included within the Gulf of Mannar Biosphere Reserve shown in Figure 1,” a comma is required before “shown” to ensure clarity and syntactic precision.

Response: Added a missing comma after the Gulf of Mannar in the sentence.

Kindly provide the full form of the abbreviation “NTPL” upon its first occurrence in the manuscript.

Response: Page 5, Lines 196-197: Added full form “Neyveli Thermal Power Limited (NTPL)”

For improved manuscript formatting and readability, please ensure that each figure is positioned immediately following the paragraph in which it is first cited.

Response: Adjusted figure placements to follow first citations

Quality of English Language: The English could be improved to more clearly express the research.

Response: Thank you for confirming that the English language quality in the manuscript meets the publication standards.

We are confident that the manuscript now adheres to the publication standards. Your constructive feedback during the major revision process was invaluable, and we thank you again for your time and dedication in helping us improve our work for publication in the ISPRS International Journal of Geo-Information.

Reviewer 2 Report

Comments and Suggestions for Authors

Study proposes a multi-criteria GIS- based Analytical Hierarchy Process (AHP) framework, incorporating remote sensing and geospatial data, to assess Solar Farm Sites (SFSs) suitability.

While the topic seems interesting, several work has been carried out in this regard hence authors might need to reconsider the novelty in this work in which sensitivity analysis of coastal city limited to India might not project so much global relevance.

Authors may want to benchmark the study area and the materials presented in methodology with other global parameters while using data from thier scope of study.

Image quality may be improved

More recent references may help improve the work

Overall the effort is commendable if the authors could look into the novelty of this work from the global relevance point of view especially with wide range of scholarly articles in this area.

Author Response

Response to Reviewer (2)

Study proposes a multi-criteria GIS- based Analytical Hierarchy Process (AHP) framework, incorporating remote sensing and geospatial data, to assess Solar Farm Sites (SFSs) suitability.

Comment 1: While the topic seems interesting, several work has been carried out in this regard hence authors might need to reconsider the novelty in this work in which sensitivity analysis of coastal city limited to India might not project so much global relevance.

Response: Thank you for this valuable feedback highlighting the need to establish global relevance and novelty. We have addressed this concern by emphasizing the unique coastal-specific challenges and transferable methodological framework in Page 3-4, Lines 142-155:

Comment 2: Authors may want to benchmark the study area and the materials presented in methodology with other global parameters while using data from thier scope of study.

Response: Thank you for this constructive suggestion to enhance global benchmarking. Page 6, Lines 223-229: Enhanced methodology section with detailed explanation of framework transferability and adaptability.

Comment 3: Image quality may be improved

Response: Thank you for the constructive feedback. All figures have been enhanced to a resolution of 1000 pixels, ensuring improved clarity and readability at 100% zoom in the PDF format.

Comment 4: More recent references may help improve the work

Response: Thank you for emphasizing the importance of current literature. We have significantly updated our reference base with recent publications. Pages 6-7, Table 1: Added comprehensive "Literature Support" column with recent references for each parameter and integrated recent references throughout the manuscript.

Comment 5: Overall the effort is commendable if the authors could look into the novelty of this work from the global relevance point of view especially with wide range of scholarly articles in this area..

Response: Thank you for acknowledging our efforts and for this important feedback on global relevance. Page 19, Lines 599-608: Enhanced discussion section with explicit focus on framework transferability and global applicability. We now clearly demonstrate how our methodology addresses unique coastal challenges while providing a replicable framework for other coastal regions worldwide.

Quality of English Language: The English could be improved to more clearly express the research.

Response: Thank you for confirming that the English language quality in the manuscript meets the publication standards.

Reviewer 3 Report

Comments and Suggestions for Authors

After reading the article "Integrating Remote Sensing and Geospatial-based Comprehensive Multi-Criteria Decision Analysis Approach for Sustainable Coastal Solar Site Selection in Southern India", I would like to offer the following comments and evaluations regarding the content, research structure, and methodological approach employed by the authors. Overall, the study presents an integrated AHP-GIS-based approach, combining remote sensing data to assess the suitability of solar energy development in coastal regions of Southern India.

The abstract effectively summarizes all key aspects of the research, including context, objectives, methodology (AHP-GIS, sensitivity analysis), results (suitability area and estimated solar energy capacity), and the main contribution. The writing is concise, clear, and aligns with current academic standards for scientific abstracts.
The authors clearly identify the research problem as the urgent need for sustainable energy transition and the gap in applying multi-criteria geospatial evaluation models for urban coastal regions. Within the context of India’s strong push for renewable energy particularly in Tamil Nadu the introduction successfully connects global goals (SDGs) with regional needs, and highlights the limitations of previous studies, such as the lack of sensitivity analysis or application in coastal environments. The writing is coherent, logically structured, and follows standard academic conventions.
The paper constructs a comprehensive site suitability assessment model using 10 criteria grouped into five factor categories (photovoltaic, climatic, topographic, environmental, and accessibility). The study applies the Analytic Hierarchy Process (AHP) to determine parameter weights and utilizes GIS for spatial analysis. The integration of sensitivity analysis and effective weight calculation strengthens the reliability of the results by revealing the actual influence of each factor. This section adheres to methodological rigor and presents a clear step-by-step research design, from data collection and preprocessing to quantitative analysis.
The conclusion clearly summarizes the key findings: 38.14% of the area shows excellent and very high suitability, with the potential to support approximately 2080 MW of solar power capacity. The study also extends its implications into smart urban planning by proposing innovative applications such as solar installations on salt pans, elevated systems in flood-prone areas, and policy incentives for dual-use infrastructure. This section is well aligned with international standards for scholarly research, demonstrating a strong link between theoretical insights and practical applications.
The article is well-structured, logically organized, and clearly written. No grammatical or typographical errors were observed. Tables, maps, and illustrations are well-labeled and integrated effectively into the discussion. The overall presentation reflects a high level of professionalism and coherence throughout the manuscript.

However, to enhance the clarity and practical implications of the study, I would like to raise the following questions for the authors' consideration:

Are there any plans to conduct pilot testing or real-world implementation in the areas identified as highly suitable for solar development?
Could this AHP-GIS model be extended to assess the suitability of other renewable energy sources such as wind power, or to non-coastal regions?
Is it possible to integrate socio-economic factors such as population density, income levels, or public acceptance of technology to enhance the model's real-world applicability and multidimensional utility?

Author Response

Response to Reviewer (3)

The abstract effectively summarizes all key aspects of the research, including context, objectives, methodology (AHP-GIS, sensitivity analysis), results (suitability area and estimated solar energy capacity), and the main contribution. The writing is concise, clear, and aligns with current academic standards for scientific abstracts.
The authors clearly identify the research problem as the urgent need for sustainable energy transition and the gap in applying multi-criteria geospatial evaluation models for urban coastal regions. Within the context of India’s strong push for renewable energy particularly in Tamil Nadu the introduction successfully connects global goals (SDGs) with regional needs, and highlights the limitations of previous studies, such as the lack of sensitivity analysis or application in coastal environments. The writing is coherent, logically structured, and follows standard academic conventions.
The paper constructs a comprehensive site suitability assessment model using 10 criteria grouped into five factor categories (photovoltaic, climatic, topographic, environmental, and accessibility). The study applies the Analytic Hierarchy Process (AHP) to determine parameter weights and utilizes GIS for spatial analysis. The integration of sensitivity analysis and effective weight calculation strengthens the reliability of the results by revealing the actual influence of each factor. This section adheres to methodological rigor and presents a clear step-by-step research design, from data collection and preprocessing to quantitative analysis.
The conclusion clearly summarizes the key findings: 38.14% of the area shows excellent and very high suitability, with the potential to support approximately 2080 MW of solar power capacity. The study also extends its implications into smart urban planning by proposing innovative applications such as solar installations on salt pans, elevated systems in flood-prone areas, and policy incentives for dual-use infrastructure. This section is well aligned with international standards for scholarly research, demonstrating a strong link between theoretical insights and practical applications.
The article is well-structured, logically organized, and clearly written. No grammatical or typographical errors were observed. Tables, maps, and illustrations are well-labeled and integrated effectively into the discussion. The overall presentation reflects a high level of professionalism and coherence throughout the manuscript.

However, to enhance the clarity and practical implications of the study, I would like to raise the following questions for the authors' consideration:

Comment 1: Are there any plans to conduct pilot testing or real-world implementation in the areas identified as highly suitable for solar development?

Response: Thank you for this valuable feedback highlighting the importance of practical validation pathways. The pilot testing was beyond the scope of our current study. Page 22-23, Lines 761-773: Added new subsection 4.4.5 "Implementation Roadmap and Validation Framework".

Comment 2: Could this AHP-GIS model be extended to assess the suitability of other renewable energy sources such as wind power, or to non-coastal regions?.

Response: Thank you for this constructive feedback about framework adaptability. Page 22, Lines 745-760: Enhanced Section 4.4.4 "Framework Adaptability and Extensions"

Comment 3: Is it possible to integrate socio-economic factors such as population density, income levels, or public acceptance of technology to enhance the model's real-world applicability and multidimensional utility?.

Response: Thank you for highlighting this important dimension for comprehensive sustainability assessment. Page 23, Lines 790-796: Enhanced Limitation Section 4.5.1 with detailed socio-economic integration pathways.

Quality of English Language: The English could be improved to more clearly express the research.

Response: Thank you for confirming that the English language quality in the manuscript meets the publication standards.

Reviewer 4 Report

Comments and Suggestions for Authors

The manuscript entitled "Integrating Remote Sensing and Geospatial-based Comprehensive Multi-Criteria Decision Analysis Approach for Sustainable Coastal Solar Site Selection in Southern India" addresses the important topic of solar site selection using an integrated remote sensing and AHP-based framework. However, several methodological and contextual issues need to be addressed before the manuscript can be considered for publication:

1. Criteria formulation and methodological rigor: The AHP decision rules and criteria weights appear to be set based on assumed conditions for the southern coastal region of India, without clear reference to empirical validation, stakeholder consultation, or established guidelines. A more transparent justification for criteria selection and weighting is needed to enhance reproducibility.

2. Comparative assessment: The analysis focuses exclusively on coastal areas without a comparative evaluation against inland or alternative regions. This omission makes it difficult to determine whether the proposed coastal sites are optimal when considering the broader geographical context.

3. Consideration of coastal-specific constraints: Key environmental challenges inherent to coastal settings, such as high humidity, salt-laden air leading to corrosion, and potential impacts of elevated temperature, humidity combinations on photovoltaic efficiency, are not sufficiently addressed. These factors could have significant implications for the long-term performance and maintenance of solar installations.

Author Response

Response to Reviewer (4)

Comment 1: Criteria formulation and methodological rigor: The AHP decision rules and criteria weights appear to be set based on assumed conditions for the southern coastal region of India, without clear reference to empirical validation, stakeholder consultation, or established guidelines. A more transparent justification for criteria selection and weighting is needed to enhance reproducibility.

Response: Thank you for this valuable feedback highlighting the need for greater methodological transparency. Page 8, Lines 264-267: Enhanced Section 2.3 with detailed expert consultation methodology. Pages 6-7, Table 1: Comprehensive Table 1 with literature support from systematic review. Page 6, Lines 218-220: Empirical validation through expert consultation with renewable energy specialists.

Comment 2: Comparative assessment: The analysis focuses exclusively on coastal areas without a comparative evaluation against inland or alternative regions. This omission makes it difficult to determine whether the proposed coastal sites are optimal when considering the broader geographical context.

Response: Thank you for this valuable feedback highlighting the need for a broader geographic context. Page 23-24, Lines 813-821: Added Section 4.5.4 "Regional Comparative Analysis". Explained deliberate coastal-specific focus for unique marine challenges and Proposed parallel inland studies for future research.

Comment 3: Consideration of coastal-specific constraints: Key environmental challenges inherent to coastal settings, such as high humidity, salt-laden air leading to corrosion, and potential impacts of elevated temperature, humidity combinations on photovoltaic efficiency, are not sufficiently addressed. These factors could have significant implications for the long-term performance and maintenance of solar installations..

Response: Thank you for emphasizing these critical coastal environmental factors that are indeed fundamental to long-term system viability. Page 12, Lines 447-456: Enhanced Section 3.1.2 with detailed coastal constraints analysis showing high humidity zones (28.68% of study area) requiring specialized equipment. Page 22, Lines 774-783: Added new Section 4.4.6 "Coastal-Specific Design and Maintenance Considerations".

Quality of English Language: The English is fine and does not require any improvement.

Response: Thank you for confirming that the English language quality in the manuscript meets the publication standards.

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

Good luck!

Author Response

Response: Thank you for this constructive feedback during the major revision process that was invaluable, and we thank you again for your time and dedication in helping us improve our work for publication in the ISPRS International Journal of Geo-Information.

Reviewer 4 Report

Comments and Suggestions for Authors

The manuscript applies a Multi-Criteria Decision Analysis (MCDA) approach; however, the current reliance on 5 expert evaluations of criteria alone is not sufficiently rigorous. This limitation becomes especially critical in coastal regions, where determining the most suitable configuration for solar panel installation is a central concern. Since this issue represents the core contribution of the paper, I believe the analysis remains underdeveloped and requires a more robust methodological foundation.

Author Response

Comments:

Response: We sincerely thank the reviewer and the academic editor for their constructive feedback, which has significantly strengthened our manuscript. In response to the concerns regarding the methodological rigor of relying on five expert evaluations for the MCDA criteria weighting, we have undertaken a series of revisions and additions:

We explicitly discuss the limitation of using a relatively small expert panel in a newly added subsection (Section 4.5.6, pp. 25, Lines 877–897), highlighting implications such as potential regional preference bias, disciplinary underrepresentation, and reduced statistical power.
We expanded our description of the expert selection process (pp. 8–9, Lines 269–287), clarifying qualifications, recruitment criteria, and the contextual challenges that constrained panel size. Supplementary Table 1 has been added to detail the disciplinary backgrounds and expertise of the participating experts.
We now provide a structured, three-phase protocol explaining how experts evaluated and weighted criteria, along with measures taken to mitigate bias and ensure representativeness (pp. 9, Lines 295–301).
We justify why expansion was not feasible and describe safeguards implemented to strengthen reliability, including consistency checks, systematic selection criteria, and aggregation through the geometric mean (pp. 8, 25).
To address robustness concerns, we introduced a comprehensive sensitivity analysis with four scenarios showing how variations in expert weights influence results. The analysis demonstrates the robustness of findings despite the small sample size (pp. 22–25, Lines 709–744, 877–897).
We further discuss how future studies could expand expert panels and diversify disciplinary and regional representation to improve generalizability and methodological rigor (pp. 25, Lines 895–897).

Collectively, these revisions provide a more transparent, methodologically sound foundation for our study while acknowledging its limitations and clarifying the role of expert input. We believe the manuscript has been substantially strengthened and now fully addresses the reviewer’s and editor’s recommendations..