Improving the Performance of Unglazed Solar Air Heating Walls Using Mesh Packing and Nano-Enhanced Absorber Coating: An Energy–Exergy and Enviro-Economic Assessment

Round 1

Reviewer 1 Report

The present work analyzed different types of solar air heating wall configurations with mesh packing and nano-enhanced absorber coating. The general structure of the study is good, and it contains valuable information. Also, the focused topic of the manuscript is within the scope of the journal. However, it needs some improvement before considering to be published. The following issues should be addressed carefully by the authors:
*Additional literature can be presented for mesh packed solar air heating systems to extend introduction section.
*Please add references about utilized procedures for preparing nano-enhanced black paint.
*Please add references for Equations (2), (12) and (19).
*Please indicate the mean deviation between the obtained environmental conditions during three experiments including solar radiation and ambient temperature to make a reliable comparison.
*Please add comparisons for the obtained performance indicators using recent similar works available in the literature. Also, comparisons need to be added for the attained enviro-economic parameters.
*Please express future research directions about this specific technology for further improvability.

Author Response

Reviewer 1:

The present work analyzed different types of solar air heating wall configurations with mesh packing and nano-enhanced absorber coating. The general structure of the study is good, and it contains valuable information. Also, the focused topic of the manuscript is within the scope of the journal. However, it needs some improvement before considering to be published. The following issues should be addressed carefully by the authors:

• Thank you for your review. Also, thank you for providing a contribution to improve the quality of this manuscript. We look forward to your feedback on the revised manuscript.

*Additional literature can be presented for mesh packed solar air heating systems to extend introduction section.

• Thank you for your constructive comment. The whole manuscript has been extended as suggested.

*Please add references about utilized procedures for preparing nano-enhanced black paint.

• Thank you for your valuable comment. The particle concentration value and preparation techniques were applied considering previous scientific studies [51,52,57-59, 62,63]. (Added to the manuscript).

*Please add references for Equations (2), (12) and (19).

• Thank you for your valuable comment. Suitable references have been added to the related equations.

*Please indicate the mean deviation between the obtained environmental conditions during three experiments including solar radiation and ambient temperature to make a reliable comparison.

• Thank you for your constructive comment. Additional explanations have been added to the related part of the manuscript.

*Please add comparisons for the obtained performance indicators using recent similar works available in the literature. Also, comparisons need to be added for the attained enviro-economic parameters.

• Thank you for your valuable comment. The obtained results were compared with similar recent works available in the literature in the results section as suggested.

*Please express future research directions about this specific technology for further improvability.

• Thank you for your valuable comment. Additional explanations for future research directions have been added to the results and conclusion.

Reviewer 2 Report

The manuscript Energy-Exergy and Enviro-Economic Analysis of Unglazed Prototype Solar Air Heating Walls with Mesh Packing and Nano-enhanced Absorber Coating submitted by Ceylin Şirin et al is one the most studied and cry of the day. The manuscript is about the effectiveness of unglazed solar air heating walls using mesh packing and nano-enhanced black paint. The authors has concluded that by using nano-doped coating and iron meshes, the mean thermal efficiencies of SW1  and SW2 were improved as 31.79% and 33.49%, respectively, this claim was successfully proved by thermodynamic studies, beside this the author study show that the payback time significantly reduced using the combination of mesh packing and  nano-doped black paint configurations, in my opinion the overall results are very interesting and applied and manuscript overall can be very beneficial for the readers of the journal, however there are number of points which should be addressed before being accepted

1. Title: The authors should modify the title and should make it self explanatory

2. Abstract: this portion should be started with "this study... and not with In this survey". Beside this the abstract part should be rewrite, this part should clearly reflect overall study.

3. Introduction: Introduction is too large and useless, the authors should reduce this portion to maximum one portion and in addition the use of very old citations should be avoided

4. Materials and methods: This portion is well written and needs no correction

5. Results and discussion: The results obtained seems very attractive but the authors should use latest citation to support their results.

6. Conclusion: The authors should not use bullets in this section, write this portion again and present your outcome.

7. References: Update the references

Finally, I recommend this manuscript in the journal after MAJOR REVISION

Minor editing of English language required

Author Response

Reviewer 2:

The manuscript Energy-Exergy and Enviro-Economic Analysis of Unglazed Prototype Solar Air Heating Walls with Mesh Packing and Nano-enhanced Absorber Coating submitted by Ceylin Şirin et al is one the most studied and cry of the day. The manuscript is about the effectiveness of unglazed solar air heating walls using mesh packing and nano-enhanced black paint. The authors has concluded that by using nano-doped coating and iron meshes, the mean thermal efficiencies of SW1  and SW2 were improved as 31.79% and 33.49%, respectively, this claim was successfully proved by thermodynamic studies, beside this the author study show that the payback time significantly reduced using the combination of mesh packing and  nano-doped black paint configurations, in my opinion the overall results are very interesting and applied and manuscript overall can be very beneficial for the readers of the journal, however there are number of points which should be addressed before being accepted

• Thank you for your review. Also, thank you for providing a contribution to improve the quality of this manuscript. We look forward to your feedback on the revised manuscript.

1. Title: The authors should modify the title and should make it self explanatory.

• Thank you for your valuable comment. The title of the manuscript has been edited as suggested.

2. Abstract: this portion should be started with "this study... and not with In this survey". Beside this the abstract part should be rewrite, this part should clearly reflect overall study.

• Thank you for your constructive comment. The abstract of the manuscript has been edited as suggested.

3. Introduction: Introduction is too large and useless, the authors should reduce this portion to maximum one portion and in addition the use of very old citations should be avoided

• Thank you for your valuable comment. The introduction has been shortened as suggested. Moreover, references from the years 2016-2023 have been used in the introduction. However, most of the used references from the last two years (2022 and 2023).

4. Materials and methods: This portion is well written and needs no correction

• Thank you for your kind comment.

5. Results and discussion: The results obtained seems very attractive but the authors should use latest citation to support their results.

• Thank you for your valuable comment. The obtained results were compared with similar recent works available in the literature in the results section as suggested.

6. Conclusion: The authors should not use bullets in this section, write this portion again and present your outcome.

• Thank you for your constructive comment. The conclusion section has been edited as suggested.

7. References: Update the references

• Thank you for your valuable comment. The references have been updated as suggested.

Finally, I recommend this manuscript in the journal after MAJOR REVISION

• Thank you for your comment.

Reviewer 3 Report

Dear Editor,

I have reviewed the manuscript titled "Energy-Exergy and Enviro-Economic Analysis of Unglazed Prototype Solar Air Heating Walls with Mesh Packing and Nano-enhanced Absorber Coating" and found the work to be quite interesting and potentially valuable to the field of solar energy utilization. The study investigates the enhancement of unglazed solar air heating walls (SWs) through the utilization of mesh packing and a nano-enhanced black paint as an absorber coating. The authors have conducted a series of experiments to evaluate the performance of different SW configurations. Overall, the research is well-structured and the findings are presented clearly. However, some minor revisions and clarifications are necessary before the manuscript can be considered for publication.

 

The manuscript generally reads well, but there are a few instances of awkward phrasing and grammar errors that need correction. I recommend a thorough proofreading and language editing to improve the overall clarity and coherence of the manuscript. 

 

*As it can be seen, decreasing the air channel (plenum) thickness, and

applying the combination of meshes and nano-coating improved the yearly carbon diox-

ide savings by 44.72%.

may also be highlighted.

 

 

 

The investigation is briefly summarized in the abstract. It may be made better, though, by briefly highlighting the main conclusions of the study, such as the amount of efficiency increase and carbon dioxide savings realized with the new SW setups. This will help readers realize the importance of the study from the abstract onward. I recommend that they rewrite some sentences.

 

It would be beneficial if the authors could elaborate on the study's context and motivation in the introduction section. Why is it crucial to improve unglazed SW performance? Are there any particular applications or sectors that these enhancements would help? As they are crucial to the study, it would also be helpful to quickly explain the ideas of energy-exergy analysis and enviro-economic analysis.

 

Explain the rationale behind choosing 2% wt/wt concentration of iron nanoparticles for the absorber coating. Was this concentration determined based on previous research or theoretical considerations?

Are there any practical constraints or operational limitations that could affect the real-world applicability of the proposed SW configurations?

 

Once these minor revisions and clarifications are addressed, I believe the manuscript will be ready for publication. The study's findings have the potential to contribute significantly to the field of solar energy utilization and environmental sustainability. I look forward to seeing the revised version of the manuscript.

Dear Editor,

I have reviewed the manuscript titled "Energy-Exergy and Enviro-Economic Analysis of Unglazed Prototype Solar Air Heating Walls with Mesh Packing and Nano-enhanced Absorber Coating" and found the work to be quite interesting and potentially valuable to the field of solar energy utilization. The study investigates the enhancement of unglazed solar air heating walls (SWs) through the utilization of mesh packing and a nano-enhanced black paint as an absorber coating. The authors have conducted a series of experiments to evaluate the performance of different SW configurations. Overall, the research is well-structured and the findings are presented clearly. However, some minor revisions and clarifications are necessary before the manuscript can be considered for publication.

 

The manuscript generally reads well, but there are a few instances of awkward phrasing and grammar errors that need correction. I recommend a thorough proofreading and language editing to improve the overall clarity and coherence of the manuscript. 

 

*As it can be seen, decreasing the air channel (plenum) thickness, and

applying the combination of meshes and nano-coating improved the yearly carbon diox-

ide savings by 44.72%.

may also be highlighted.

 

 

 

The investigation is briefly summarized in the abstract. It may be made better, though, by briefly highlighting the main conclusions of the study, such as the amount of efficiency increase and carbon dioxide savings realized with the new SW setups. This will help readers realize the importance of the study from the abstract onward. I recommend that they rewrite some sentences.

 

It would be beneficial if the authors could elaborate on the study's context and motivation in the introduction section. Why is it crucial to improve unglazed SW performance? Are there any particular applications or sectors that these enhancements would help? As they are crucial to the study, it would also be helpful to quickly explain the ideas of energy-exergy analysis and enviro-economic analysis.

 

Explain the rationale behind choosing 2% wt/wt concentration of iron nanoparticles for the absorber coating. Was this concentration determined based on previous research or theoretical considerations?

Are there any practical constraints or operational limitations that could affect the real-world applicability of the proposed SW configurations?

 

Once these minor revisions and clarifications are addressed, I believe the manuscript will be ready for publication. The study's findings have the potential to contribute significantly to the field of solar energy utilization and environmental sustainability. I look forward to seeing the revised version of the manuscript.

Author Response

Reviewer 3:

The investigation is briefly summarized in the abstract. It may be made better, though, by briefly highlighting the main conclusions of the study, such as the amount of efficiency increase and carbon dioxide savings realized with the new SW setups. This will help readers realize the importance of the study from the abstract onward. I recommend that they rewrite some sentences.

• Thank you for your review. Also, thank you for providing a contribution to improve the quality of this manuscript. We look forward to your feedback on the revised manuscript.
• Thank you for your constructive comment. The abstract has been edited as suggested.

It would be beneficial if the authors could elaborate on the study's context and motivation in the introduction section. Why is it crucial to improve unglazed SW performance? Are there any particular applications or sectors that these enhancements would help? As they are crucial to the study, it would also be helpful to quickly explain the ideas of energy-exergy analysis and enviro-economic analysis.

• Thank you for your constructive comment. The introduction section has been edited as suggested. Moreover, additional explanations about energy-exergy and enviro-economic analyses have been added to the manuscript.

Explain the rationale behind choosing 2% wt/wt concentration of iron nanoparticles for the absorber coating. Was this concentration determined based on previous research or theoretical considerations?

• Thank you for your valuable comment. The particle concentration value and preparation techniques were applied considering previous scientific studies [51,52,57-59, 62, 63]. (Added to the manuscript).

Are there any practical constraints or operational limitations that could affect the real-world applicability of the proposed SW configurations?

• Thank you for your constructive comment. In this work, two types of modifications including mesh packing and nano-enhanced black paint in solar walls have been investigated for performance improvement. In future studies, SWs with larger scales can be developed to analyze their potential usage in building systems considering thermal loads. In other words, the utilized modifications in this study could be applied to available commercial applications of SWs. Moreover, long-term durability observations of the presented modifications should be done. (Added to the manuscript).

Once these minor revisions and clarifications are addressed, I believe the manuscript will be ready for publication. The study's findings have the potential to contribute significantly to the field of solar energy utilization and environmental sustainability. I look forward to seeing the revised version of the manuscript.

• Thank you for your kind comments.

Reviewer 4 Report

In this work, Şirin et al. demonstrated the effectiveness of unglazed solar air heating walls (SWs) using mesh packing and nano-enhanced black paint. The performance of the material is good, and the topic is very interesting. However, the manuscript needs to be could be polished before possible publication.

1.      Here are some possible concerns regarding the role of iron (Fe) in this work that needs to be addressed, the use of nanoparticles in black paint raises concerns about potential environmental impacts.

·        Iron is susceptible to corrosion when exposed to air and moisture, which could potentially reduce the longevity and performance of the solar air heating walls (SWs). The use of iron meshes and iron nanoparticle-enhanced black paint might lead to degradation over time, affecting the overall efficiency and effectiveness of the system.

·        If the iron components of the SWs require regular maintenance and upkeep to prevent corrosion or other issues, this could increase the operational complexity and cost of the system. Proper maintenance procedures and schedules would need to be established to ensure long-term performance.

 

2.      The abstract mentions that the research focuses on two specific cases of solar air heating walls with plenum thicknesses of 10 cm and 15 cm. It's important to consider the generalizability of the findings to other plenum thicknesses or different design parameters. The effectiveness of the proposed enhancements might vary for different configurations.

 

3.      The investigations don't discuss the long-term durability of the mesh packing and nanoparticle-enhanced black paint. Weather conditions, temperature variations, and exposure to sunlight might affect the performance of these enhancements over time.

 

4.      While the work highlights improvements in efficiency and carbon dioxide savings, there's no mention of the cost implications of implementing these enhancements. The cost of materials, manufacturing, and maintenance could impact the overall economic viability of the proposed solutions.

5.      The results don't discuss the sensitivity of the results to various parameters. Factors such as solar irradiance, ambient temperature, and humidity levels could influence the effectiveness of the proposed enhancements.

 

 

Author Response

Reviewer 4:

1. Here are some possible concerns regarding the role of iron (Fe) in this work that needs to be addressed, the use of nanoparticles in black paint raises concerns about potential environmental impacts.

• Thank you for your review. Also, thank you for providing a contribution to improve the quality of this manuscript. We look forward to your feedback on the revised manuscript.
• Thank you for your constructive comment. In this study, the enviro-economic analysis has been performed to determine the effect of using a sustainable solar air heating wall in air heating process instead of utilizing conventional energy sources. It is known that nanoparticles have high embodied energy, and it might increase the overall embodied energy of the system. In further works, life cycle analysis is planned to be performed to evaluate the overall environmental impacts of the developed systems. (Added to the manuscript).
• Iron is susceptible to corrosion when exposed to air and moisture, which could potentially reduce the longevity and performance of the solar air heating walls (SWs). The use of iron meshes and iron nanoparticle-enhanced black paint might lead to degradation over time, affecting the overall efficiency and effectiveness of the system. If the iron components of the SWs require regular maintenance and upkeep to prevent corrosion or other issues, this could increase the operational complexity and cost of the system. Proper maintenance procedures and schedules would need to be established to ensure long-term performance.
• Thank you for your constructive comment. Additional explanations have been added to the manuscript.
• “…Iron meshes are cost-effective extended heat transfer surfaces and can be used in various solar energy systems. However, iron meshes may have some disadvantages such as the possibility of corrosion in long-term use. Since the iron meshes are quite low cost and available in the worldwide market, they can be replaced easily for maintaining the SWs…”
• “…It should be noted that prototype SWs have been designed, manufactured, and tested in this work. In future studies, SWs with larger scales can be developed to analyze their potential usage in building systems considering thermal loads. In other words, the utilized modifications in this study could be applied to available commercial applications of SWs. Moreover, long-term durability observations of the presented modifications should be done…”

2. The abstract mentions that the research focuses on two specific cases of solar air heating walls with plenum thicknesses of 10 cm and 15 cm. It's important to consider the generalizability of the findings to other plenum thicknesses or different design parameters. The effectiveness of the proposed enhancements might vary for different configurations.

• Thank you for your valuable comment. The analyzed SWs in this study have been designed according to the previous studies of our research group. In previous studies, the applicability of SWs with various modifications have been analyzed. Different from previous studies, in the present work the effects of using two modifications on the thermal performance of unglazed SWs have been experimentally analyzed. The geometrical parameters have no significant impact on performance improvement of nano-coating. However, as you stated, adding mesh modification in different systems may have various effects. Therefore, it is necessary to investigate the effect of using iron mesh modification in different systems. Moreover, the effect of plenum thickness on the performance has been analyzed using an important indicator called effective efficiency. (Added to the manuscript).

3. The investigations don't discuss the long-term durability of the mesh packing and nanoparticle-enhanced black paint. Weather conditions, temperature variations, and exposure to sunlight might affect the performance of these enhancements over time.

• Thank you for your constructive comment. Additional explanations have been added to the conclusion section about the stated concerns.

4. While the work highlights improvements in efficiency and carbon dioxide savings, there's no mention of the cost implications of implementing these enhancements. The cost of materials, manufacturing, and maintenance could impact the overall economic viability of the proposed solutions.

• Thank you for your valuable comment. In the present survey, energy, exergy and enviro-economic analyses have been investigated. In further works, life cycle analysis is planned to be performed to evaluate the developed systems environmentally in detail.

5. The results don't discuss the sensitivity of the results to various parameters. Factors such as solar irradiance, ambient temperature, and humidity levels could influence the effectiveness of the proposed enhancements.

• Thank you for your constructive comment. As can be seen in the results section, the environmental parameters are quite close to each other, and this fact allows us to make a reliable comparison between the developed configurations. In further works, the effects of various ambient conditions on the performance of SWs can be modeled using effective tools such as response surface methodology.

Reviewer 5 Report

The review of the manuscript ID sustainability-2607947-peer-review-v1

 

The following points should be answered carefully:

1.     It is necessary to include a paragraph describing the physical process in Solar Air Heating Walls with a schematic representation of all heat transfer processes.

2.     It is necessary to describe in more detail the physical processes in the configurations presented in Fig.4 (SW1 and SW2) indicating the mechanisms of heat transfer and novelty in the geometric configuration.

3.     It is necessary to describe the experimental procedures in more detail (Exp.1, Exp.2, and Exp.3).

4.     Describing the measuring devices indicated in Fig.3 is also necessary.

 

The status is “Accept with Minor Revision”.

Author Response

Reviewer 5:

The following points should be answered carefully:

• Thank you for your review. Also, thank you for providing a contribution to improve the quality of this manuscript. We look forward to your feedback on the revised manuscript.

1. It is necessary to include a paragraph describing the physical process in Solar Air Heating Walls with a schematic representation of all heat transfer processes.

• Thank you for your constructive comment. A schematic diagram and an additional paragraph have been added to the manuscript according to your suggestion.

2. It is necessary to describe in more detail the physical processes in the configurations presented in Fig.4 (SW1 and SW2) indicating the mechanisms of heat transfer and novelty in the geometric configuration.

• Thank you for your valuable comment. Additional explanations have been added to the related section.

3. It is necessary to describe the experimental procedures in more detail (Exp.1, Exp.2, and Exp.3).

• Thank you for your constructive comment. Additional explanations have been added for the experimental procedure.

4. Describing the measuring devices indicated in Fig.3 is also necessary.

• Thank you for your valuable and constructive comment. New statements have been added for describing measurement devices as suggested.

 

 

Round 2

Reviewer 2 Report

The authors has incorporated all the changes suggested so I feel pleasure to accept this manuscript

Author Response

Dear Editor

Thanks for all of the reviewers and editor for reviewing the manuscript. Also, the authors especially appreciate the constructive comments, support and contributions of the editor and reviewers that were helped to improve the quality of the paper. Thank you for giving the opportunity to revise our paper. We did our best to improve it. You will find below the answers to the remarks. Marked Manuscript (R2) and Unmarked Manuscript (R2) have been added to Editorial System. We look forward to your feedback on the revised manuscript.

(I) We have checked the references in your manuscript and found that approximately 26 of them are related to the authors. Therefore, we kindly suggest that you significantly replace or reduce self-citation references to no more than three for each author. Please check that all references are relevant to the contents of the manuscript.

• Thank you for your constructive comment. The references have been checked and 24 self-citations were found. As suggested, 15 of them were removed from the manuscript and critical 9 of them were kept in the text. This value is 3 self-citations per author.

(II) As a journal, we tend to address challenges related to sustainable, socio-economic, scientific and integrated approaches to sustainable development. During revision, it would be greatly appreciated if you could describe, in detail, how your research contributes to sustainability.  Please address the topic of sustainability in your research paper.

• Thank you for your constructive comment. Additional explanations have been added to the conclusion section about the effect of the general outcomes of this work on a sustainable future.