Detection of Contaminants in Hydrogen Fuel for Fuel Cell Electrical Vehicles with Sensors—Available Technology, Testing Protocols and Implementation Challenges

Round 1

Reviewer 1 Report

This paper of ..

Detection of contaminants in Hydrogen fuel for FCEV with sensors - available technology, testing protocols and implementation challenges

General comment

investigate different hydrogen technologies of sensor and application including some information about application such as fuel cell and electric car..etc in Europe and other countries. This paper covers hydrogen quality control important requirements with respect to contaminants, high sensitivity, integration parameters and cost. This paper focus on using the existing detection sensor technologies to detect contaminants in hydrogen and its implementation in refueling stations.

The subject of study is needed in the sector, and the use of Hydrogen as alternative energy resource is important, in particular refueling station. One of the main issues of using hydrogen is the cost of production, storage, …and refueling station development and cost, which has not been covered in depth in this study, and thus I recommend adding few sections to cover it.

It was obvious that Section 4.2 through to Conclusion section need to be re-written, serious format issue, used incorrect numbering format figure tables sections etc

Specific Comments

Objective

The objectives of this paper are first to review the sensor technologies existing for species that need to be monitored and describe how the performance of these sensor technologies are/can be assessed and finally to discuss how they can be implemented and calibrated at a HRS. but what is the authors contributions

My specific commendations and recommendations are:

1. The paper is a quality paper, and well written up to section 4.2.
2. Introduction
   1. Very nice paragraph (32-38) to introduce the reader into the subject. But this requires more reference, Ref 1 is not sufficient.
   2. Line 41/42 sensing technology?
   3. Good work to justify the relationship between the need of the contamination process and the safety – line 56-68.
3. FCEV – need to be written in full Fuel Cell Electrical Vehicle (FCEV).
4. I suggest the authors to add more information about the challenges and opportunities as well the effect of using hydrogen globally.
5. Lin 204-207 to shift to 2.9 section “ A recent work from EPA underlines the lack of standard testing protocols, metrics, …or targets to evaluate the performance of air sensors uniformly. Need evident/reference to support this claim
6. Remove line 348
7. Type of sensor section is well covered.
8. Line 328-329,

I stopped reading here

9. Section 4.2 need to reformat/rewritten, Section 1.2.1 “The Shared Sensor Technology User Facility (SSTUF) 361…should be 4.2.1..Figure 1,2,3.. should be Figure 4,5,6…etc..
10. I cant find section 2.10 ?
11. …more issues with format, numbering etc.

In conclusion, the first half of the paper is well written, however section 4.2 through to Conclusion section need to be re-written and used correct numbering format figure tables sections etc….

I recommend the paper to be resubmitted with accurate format.

 

 

Author Response

Responses to reviewer 1:

1. The paper is a quality paper, and well written up to section 4.2.
2. Introduction
1. Very nice paragraph (32-38) to introduce the reader into the subject. But this requires more reference, Ref 1 is not sufficient.

Response: two references have now been added to support the information provided in this paragraph

1. Line 41/42 sensing technology?

Response: The change was made (sensing technology instead of sensing technologies)

1. Good work to justify the relationship between the need of the contamination process and the safety – line 56-68.
1. FCEV – need to be written in full Fuel Cell Electrical Vehicle (FCEV).

Response: this has been changed in the title

1. I suggest the authors to add more information about the challenges and opportunities as well the effect of using hydrogen globally.

Response: this is partially covered in the introduction. The challenge that we address in this article is the need to control online and at a reasonable cost, the quality of the hydrogen delivered at a HRS

1. Lin 204-207 to shift to 2.9 section “ A recent work from EPA underlines the lack of standard testing protocols, metrics, …or targets to evaluate the performance of air sensors uniformly. Need evident/reference to support this claim

Response: The reference to the work from EPA has been added

1. Remove line 348
2. Type of sensor section is well covered.
3. Line 328-329,

I stopped reading here

1. Section 4.2 need to reformat/rewritten, Section 1.2.1 “The Shared Sensor Technology User Facility (SSTUF) 361…should be 4.2.1..Figure 1,2,3.. should be Figure 4,5,6…etc..

Response: We have now fixed the problem with the numbering of the Figures and the sections. As rightfully suggested by the reviewer, an extensive revision of the sections 4.2, 5, 6 and 7 has been done

1. I cant find section 2.10 ?

Response: The reference to section 2.10 has been removed and replaced with the correct reference (2.8)

1. …more issues with format, numbering etc.

Response: this has been fixed while rewriting all the sections after 4.1.

 

Reviewer 2 Report

The paper is well-structured and clearly explained.

Author Response

no comment to handle

Reviewer 3 Report

This manuscript discusses the recent advances and issues about the detection of contaminants in hydrogen fuel for FCEV. As the suggestion of the authors, the quality control and sensing of the contaminant in hydrogen at hydrogen refueling station (HRS) is getting critical, and the related technologies are received attention in recent years. Especially, contaminant sensing is becoming a more crucial technology due to getting diverse sources and production methods of hydrogen fuels. Thus, I think this review is an opportune article to trigger the discussion in related industries. Moreover, given that this manuscript has enough profitable and well-organized information for this issue, I would like to recommend publishing in processes without further revision.

Author Response

no comment from the reviewer

Round 2

Reviewer 1 Report

I cant see the review comment file, which is a must

Author Response

Dear reviewer,

The version with the changes marked in red is attached here,

Responses to reviewer 1:

1. The paper is a quality paper, and well written up to section 4.2.
2. Introduction
1. Very nice paragraph (32-38) to introduce the reader into the subject. But this requires more reference, Ref 1 is not sufficient.

Response: two references have now been added to support the information provided in this paragraph

1. Line 41/42 sensing technology?

Response: The change was made (sensing technology instead of sensing technologies)

3. Good work to justify the relationship between the need of the contamination process and the safety – line 56-68.

4. FCEV – need to be written in full Fuel Cell Electrical Vehicle (FCEV).

Response: this has been changed in the title

5. I suggest the authors to add more information about the challenges and opportunities as well the effect of using hydrogen globally.

Response: this is partially covered in the introduction. The challenge that we address in this article is the need to control online and at a reasonable cost, the quality of the hydrogen delivered at a HRS

6. Lin 204-207 to shift to 2.9 section “ A recent work from EPA underlines the lack of standard testing protocols, metrics, …or targets to evaluate the performance of air sensors uniformly. Need evident/reference to support this claim

Response: The reference to the work from EPA has been added

Type of sensor section is well covered.

7. Section 4.2 need to reformat/rewritten, Section 1.2.1 “The Shared Sensor Technology User Facility (SSTUF) 361…should be 4.2.1..Figure 1,2,3.. should be Figure 4,5,6…etc..

Response: We have now fixed the problem with the numbering of the Figures and the sections. As rightfully suggested by the reviewer, an extensive revision of the sections 4.2, 5, 6 and 7 has been done

8. I cant find section 2.10 ?

Response: The reference to section 2.10 has been removed and replaced with the correct reference (2.8)

9. …more issues with format, numbering etc.

Response: This has been fixed while rewriting all the sections after 4.1.

 

Author Response File: Author Response.docx

Round 3

Reviewer 1 Report

Happy to recommend this paper for publication as it is