Design and Optimization of a Backup Renewable Energy Station for Photovoltaic Hybrid System in the New Jeddah Industrial City

Round 1

Reviewer 1 Report

The presented article is a calculation of a backup power plant based on renewable energy in Saudi Arabia. The topic of the article is relevant and may be of interest to specialists and researchers in the fields of renewable energy and sustainable development. The authors in the article provide a detailed calculation of the power plant in the program, however, as comments and recommendations, several points should be noted:

1. Authors should pay special attention to the design of the article according to the journal template.

2. What justifies the choice of software for calculations and design?

3. What is the scientific novelty of the work - the authors should highlight it in comparison with existing works and studies.

4. The literature review and the list of sources used is too small - the authors should consider modern research on the topic under consideration from high-ranking international journals.

5. The authors assume a lifetime of 25 years and efficiency about 21% for photovoltaic modules, however, the economics of the project can greatly change for the better when using solar modules with an extended service life of up to 40-50 years and an efficiency of more than 21% (for example, DOI: 10.4018/978-1-7998-9152-9.ch030 etc.), which are already exist and are appropriate for use in the region under consideration - in the present or future studies, it is appropriate for the authors to pay attention to this and not be limited by program restrictions.

6. Does the system not include a fossil fuel generator? Is it possible that wind and solar radiation will be absent simultaneously for a long time?

7. The quality of Figures 5 and 9 should be improved. On line 206, "22.7o" should be replaced with "degree".

8. What personal new scientific proposals are put forward by the authors, since most of the work is an engineering calculation of the program?

9. What is the optimization criterion when searching for the optimal system - the authors should describe it in detail in the paper.

10. How do the authors plan to implement the obtained results?

11. Authors should indicate the contribution of each author to the content of the work.

In general, the presented article leaves a positive impression, however, it is not without flaws. After eliminating these comments and taking into account the recommendations made, the presented article can be recommended for publication in the journal "Sustainability".

Author Response

#Reviewer 1:

The presented article is a calculation of a backup power plant based on renewable energy in Saudi Arabia. The topic of the article is relevant and may be of interest to specialists and researchers in the fields of renewable energy and sustainable development. The authors in the article provide a detailed calculation of the power plant in the program, however, as comments and recommendations, several points should be noted:

1. Authors should pay special attention to the design of the article according to the journal template.

Response:

Thanks to this comment, article is improved according to the journal guide.

2. What justifies the choice of software for calculations and design?

Response:

Thanks to this comment, the design and evaluation of technical and financial requirements will be performed using HOMER software. HOMER displays simulation results in a wide variety of tables and graphs that help you compare configurations and evaluate them on their economic and technical merits.

3. What is the scientific novelty of the work - the authors should highlight it in comparison with existing works and studies.

Response:

Thanks to this comment, the backup power plant will mainly use wind energy. If the energy produced from the wind turbines is insufficient, it will be supplemented by the energy produced from solar energy. The primary importance of the research is to provide an urgent solution for the workshops to overcome the power shortage.

4. The literature review and the list of sources used is too small - the authors should consider modern research on the topic under consideration from high-ranking international journals.

Response:

Thanks to this comment, the literature review is improved by adding more relevant studies.

5. The authors assume a lifetime of 25 years and efficiency about 21% for photovoltaic modules, however, the economics of the project can greatly change for the better when using solar modules with an extended service life of up to 40-50 years and an efficiency of more than 21% (for example, DOI: 10.4018/978-1-7998-9152-9.ch030 etc.), which are already exist and are appropriate for use in the region under consideration - in the present or future studies, it is appropriate for the authors to pay attention to this and not be limited by program restrictions.

Response:

Thanks to this comment, yes, this idea worth investigations and solar modulus are great in industries, in the future study section, it is mentioned. Still, solar power is only available during the day, and the grid and battery are the principal sources of electricity at night.

6. Does the system not include a fossil fuel generator? Is it possible that wind and solar radiation will be absent simultaneously for a long time?

Response:

Thanks to this comment, no it does not include a fossil fuel generator. However, it has a Diesel generator (Fig. 4)

When solar irradiance is poor, Wind speed, on the other hand, is relatively low throughout the summer season, when solar radiation on the earth's surface is relatively high, allowing energy to be generated. As a result, combining solar and wind energy can provide a year-round source of electricity.

7. The quality of Figures 5 and 9 should be improved. On line 206, "22.7o" should be replaced with "degree".

Response:

Thanks to this comment, quality of both figures is improved.

Also, “22.7o” was replaced with “22.7 degree”

8. What personal new scientific proposals are put forward by the authors, since most of the work is an engineering calculation of the program?

Response:

Thanks to this comment, power shortage in the industrial city makes great losses in the money, which affects the financial affairs of workshops. The primary importance of the research is to provide an urgent solution for the workshops to overcome the power shortage. This project aims to design and optimize a backup renewable energy station for the 2nd Jeddah industrial city workshops.

9. What is the optimization criterion when searching for the optimal system - the authors should describe it in detail in the paper.

Response:

Thanks to this comment, figure 6 shows that the best solution is a grid-connected 500 kW PV system with a 303-kW converter and 5 strings of 100 kWh batteries. The total annual power generation from this configuration is 2017268 kWh/yr. The energy requirement is satisfied by a combination of grid purchases and solar energy, as shown in Table 3, with a proportion of 53.5% and 46.5% correspondingly.

10. How do the authors plan to implement the obtained results?

Response:

Thanks to this comment, the lack of comprehensive data on total and detailed electricity consumption for all factories in Jeddah's second industrial city, as well as factory owners' reluctance to provide us with information, necessitated this study. These data will help companies in the mentioned industrial city to optimize their outputs.

11. Authors should indicate the contribution of each author to the content of the work.

Response:

Thanks to this comment, CRediT author statement section is added.

In general, the presented article leaves a positive impression, however, it is not without flaws. After eliminating these comments and taking into account the recommendations made, the presented article can be recommended for publication in the journal "Sustainability".

 

 

Author Response File: Author Response.pdf

Reviewer 2 Report

The review comments for the manuscript, 'DESIGN AND OPTIMIZATION OF A BACKUP RENEWABLE ENERGY STATION FOR PHOTOVOLTAIC HYBRID SYSTEM IN THE NEW JEDDAH INDUSTRIAL CITY', are given below,

1. The authors presented an analysis on HRE based power supply to the city of Jeddah. The work is interesting but not novel. So many changes to be done in the manuscript for betterment. 

2. Introduction part is very weak. It must be updated with more recent literature. Also add the organization of the manuscript at the end of Introduction Section for quick go through. 

3. I can find so many typos and grammatical errors throughout the manuscript. It must be checked carefully, also the SI units. Example: kW and KW in abstract.

4. Refer this manuscript for other details, 10.1080/03772063.2020.1787239 also compare. 

5. Article title must be modified, include all the sources or mention only RES.

6. Quality of all the figures must be improved. It looks like cropping the data directly from the HOMER software, so, collect the data from HOMER and redraw all the graphs. 

7. The write-up/organization is not proper. Divide the section 3 into two. So, it may look organized. 

8. Is the Diesel generator and the grid purchases are same?

9. Use proper heading numbers, do not use logos in heading, it is very difficult to classify and read.

10. Abstract and conclusion must be precise and brief.

 

Author Response

 

#Reviewer 2:

The review comments for the manuscript, 'DESIGN AND OPTIMIZATION OF A BACKUP RENEWABLE ENERGY STATION FOR PHOTOVOLTAIC HYBRID SYSTEM IN THE NEW JEDDAH INDUSTRIAL CITY', are given below,

1. The authors presented an analysis on HRE based power supply to the city of Jeddah. The work is interesting but not novel. So many changes to be done in the manuscript for betterment.

Response:

The paper was totally modified and improved.

2. Introduction part is very weak. It must be updated with more recent literature. Also add the organization of the manuscript at the end of Introduction Section for quick go through.

Response:

Thanks to this comment, the literature review is improved by adding more relevant studies. Also, organization of the manuscript at the end of Introduction Section is added.

3. I can find so many typos and grammatical errors throughout the manuscript. It must be checked carefully, also the SI units. Example: kW and KW in abstract.

Response:

Thanks to this comment, typos and grammatical errors throughout the manuscript are re-checked and text is improved.

4. Refer this manuscript for other details, 10.1080/03772063.2020.1787239 also compare.

Response:

Thanks to this comment, the mentioned manuscript is added in the literature review.

5. Article title must be modified, include all the sources or mention only RES.

Response:

Thanks to this comment, title is improved and “RENEWABLE ENERGY STATION” was changed to “RES”

6. Quality of all the figures must be improved. It looks like cropping the data directly from the HOMER software, so, collect the data from HOMER and redraw all the graphs.

Response:

Thanks to this comment, all of the figures are re-checked and the quality is improved.

7. The write-up/organization is not proper. Divide the section 3 into two. So, it may look organized.

Response:

Thanks to this comment, article is improved according to the journal guide.

8. Is the Diesel generator and the grid purchases are same?

Response:

Thanks to this comment, Diesel generator is not as same as battery packs or solar panels (Fig. 4).

9. Use proper heading numbers, do not use logos in heading, it is very difficult to classify and read.

Response:

Thanks to this comment, all of the headings are re-checked and edited.

10. Abstract and conclusion must be precise and brief.

Response:

Thanks to this comment, both abstract and conclusion are re-checked and improved.

Author Response File: Author Response.pdf

Reviewer 3 Report

The following suggestions/comments can be included in the manuscript before acceptance of the manuscript into the journal. 

1. The abstract should be modified with core novelty and findings of the current research. 

2. The novelty of the current research should be highlighted and the motivation for the current research should be included in the last paragraph of the manuscript. 

3. The methodology can be pictorially represented for better visualization of the manuscript. 

4. The factors like installation space, installation investment, maintenance of the hybrid systems, etc., can also be included in the survey for better justification of factory requirements. 

5. The environmental issues should be considered for a case study to be presented for future use.

6. What happens to the products in the installation after their life? The end-of-life concept should be included in the manuscript. 

7. The font size and style should be uniform across the manuscript.

8. The results are to be discussed more with the science behind the occurrences. 

9. The conclusion should be more aggressive and the case study should give future aspects/suggestions to achieve the SDGs. Hence conclusions require major modification in the manuscript. 

Author Response

 

#Reviewer 3:

The following suggestions/comments can be included in the manuscript before acceptance of the manuscript into the journal.

1. The abstract should be modified with core novelty and findings of the current research.

Response:

Thanks to this comment, abstract is modified with core novelty and findings of the current research.

2. The novelty of the current research should be highlighted and the motivation for the current research should be included in the last paragraph of the manuscript.

Response:

Thanks to this comment, in the end of introduction, both novelty and aims of this study plus importance of the research are added.

3. The methodology can be pictorially represented for better visualization of the manuscript.

Response:

Thanks to this comment, Figure 4 shows HOMER system in methodology section.

4. The factors like installation space, installation investment, maintenance of the hybrid systems, etc., can also be included in the survey for better justification of factory requirements.

Response:

Thanks to this comment, the mentioned factors are included in methodology-hybrid system section.

5. The environmental issues should be considered for a case study to be presented for future use.

Response:

Thanks to this comment, the mentioned issue is added in the future research section.

6. What happens to the products in the installation after their life? The end-of-life concept should be included in the manuscript.

Response:

Thanks to this comment, end-of-life concept is added at the end of conclusion section.

7. The font size and style should be uniform across the manuscript.

Response:

Thanks to this comment, font size and style is edited across the manuscript.

8. The results are to be discussed more with the science behind the occurrences.

Response:

Thanks to this comment, results are re-checked and improved.

9. The conclusion should be more aggressive and the case study should give future aspects/suggestions to achieve the SDGs. Hence conclusions require major modification in the manuscript.

Response:

Thanks to this comment, conclusion section is edited and improved. Also, Sustainable Development Goals (DSGs), Goal 7 and Goal 11 are added in future suggestions.

 

 

Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors are attached.

Comments for author File: Comments.pdf

Author Response

 

#Reviewer 4:

Review of “DESIGN AND OPTIMIZATION OF A BACKUP RENEWABLE ENERGY STATION FOR PHOTOVOLTAIC HYBRID SYSTEM IN THE NEW JEDDAH INDUSTRIAL CITY”

1. In Lines 1-3, The article title is a bit confusing. It should be clear.

Response:

Thanks to this comment, title is improved and “RENEWABLE ENERGY STATION” was changed to “RES” and “New Jeddah” is changed to “New-Jeddah”

2. In Lines 11-20, the typos in the Abstract section should be corrected. The use of units must be consistent.

Response:

Thanks to this comment, the typos in the Abstract section are corrected.

3. In Lines 23-88, The typos in Introduction should be corrected. The use of abbreviations should be consistent. For example, “the HOMER” or “homer”.

Response:

Thanks to this comment, “HOMER” is used in entire manuscript. The typos in Introduction are corrected.

4. In Lines 94-96, the sentence should be rewritten. In this way the meaning remains ambiguous.

Response:

Done.

5. In Lines 100-101, the sentence should be reworded. In this way the meaning remains ambiguous.

Response:

Done.

6. The load demand given in Figure 1 is the daily demand of a company located in an industrial city. Whereas, this load demand should be that of the industrial city. The other issue is that the load demands any day of the year? An average of one day in a year? Is it always the same all year round? Is there a change affected by environmental conditions here? These points should be identified.

Response:

The lack of comprehensive data on total and detailed electricity consumption for all factories in Jeddah's second industrial city, as well as factory owners' reluctance to provide us with information, necessitated this study, which investigated and designed an optimal hybrid system for Abdullah Hashim Industrial Gases & Equipment Co. Ltd. The HOMER grid was used to create and simulate the system, which has a 25-year life cycle.

Because alternative energy is not common in Saudi Arabia due to the abundance of fossil fuels, the country's total reliance on electricity generation has been based on the use of fossil fuels until now. Therefore, the system's payback is solely based on monthly grid bill savings and increased profits due to the absence of a power shortage.

7. Are there any capacity increases or new investments in the survey questions given in Table 1? They may be asked. There may be a change in the forward demanded power. Based on this, survey questions can be created.

Response:

Thanks to this comment, the mentioned survey question is added in Table 1.

8. In Lines 110-117, general information is repeated in this section. More concrete information should be given about the hybrid system. For example, technical information should be given about the structure and power of the system.

Response:

Done.

9. In Lines 118-134, although the annual estimated solar radiation and wind speed data for the region in this section give an idea, but the measured data on the location itself should be accurate. Therefore, measuring wind speed and solar radiation data for one year is a more realistic approach. Another consideration is that the wind speed data in Figure 2 indicates that limited power generation will be possible or may be not sufficient. However, the solar radiation data in Figure 3 shows a good potential for a solar PV system. It is inevitable that there will be a serious decrease in efficiency due to the high ambient temperature. Therefore, essential information should be given about the cooling measures to be taken for the proposed system.

Response:

Thanks to this comment, because alternative energy is not common in Saudi Arabia due to the abundance of fossil fuels, the country's total reliance on electricity generation has been based on the use of fossil fuels until now. Therefore, the system's payback is solely based on monthly grid bill savings and increased profits due to the absence of a power shortage.

10. In Lines 135-143, this section should introduce the technical features of solar PV. For example, current-voltage and power-voltage characteristics, manufacturer’s data sheet, etc. Cost analysis should be done elsewhere.

Response:

Thanks to this comment, technical features of solar PV are added. Cost analysis should remain due to the comment of another respectful reviewer.

11. In Lines 144-150, technical specifications of wind turbines should be introduced in this section. For example, the type and power curve of the wind turbine, as well as the manufacturer's data sheet, etc. Again, cost analysis should be done elsewhere.

Response:

Thanks to this comment, technical specifications of wind turbines are added. Cost analysis should remain due to the comment of another respectful reviewer.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

The review comments for the revised manuscript are given below,

1. The authors revised the manuscripts according to the comments.

2. All the suggested corrections given by myself and other reviewers were incorporated and addressed well.

3. I recommend this manuscript may be accepted for publication in the present form.

Thank you for the contribution. 

Author Response

Thank you so much.

Reviewer 3 Report

Can be accepted in its current form

Author Response

Thank you so much.

Reviewer 4 Report

It is attached separately.

Comments for author File: Comments.pdf

Author Response

#Reviewer 4

1. Spelling mistakes should be corrected. In the text, it should be photovoltaic, not Photovoltaic.

Response:

Thanks to this comment, all of the abbreviations are re-checked and their full form words are lowercased.

 

2. Abstract should be reworded. It does not fully summarize the work.

Response:

Thanks to this comment, Abstract section is re-checked and some sentences are added to improve this section (considering the limitation of 200-words for this section).

 

3. Keywords should be chosen more appropriately and broadly.

Response:

Thanks to this comment, Keywords section is re-checked and it is improved.

 

4. A Nomenclature section should be included for the abbreviations and symbols used in the article.

Response:

Thanks to this comment, an Abbreviations table is added before the Introduction section.

 

5. It would be better to use “This study” instead of “This project”.

Response:

Thanks to this comment, this sentence is improved.

 

6. Table 1 should be arranged in accordance with the format. This way is not appropriate.

Response:

Thanks to this comment, Table 1 is removed and the content is added to the previous paragraph.

 

7. Figure 4 should be given more appropriately. For example, the PV system can be called instead of a Photovoltaic.

Response:

Thanks to this comment, Figure 4 is edited.

 

8. The title of Section 3.2 should be “Simulation results”.

Response:

Thanks to this comment, the heading is corrected.

 

9. Table 2 should be rearranged. The SAR currency is given in the cost columns, there is no need to give it again. Architecture column headings should change. For example, PV Module can be used instead of SPR-X21. Others should be modified in a similar way.

Response:

Thanks to this comment, the table is re-arranged and improved.

 

10. Figure 6 should be given in a more appropriate form as a schematic diagram. The text below the figure is not suitable for the format. It has to be formatted.

Response:

Thanks to this comment, Figure 6 is edited.

 

11. Section 3.3 should be bold.

Response:

Thanks to this comment, Section “3.3. The first configuration” is bolded.

 

12. The two tables in Table 3 should be properly combined into one table.

Response:

Thanks to this comment, both tables are merged together.

 

13. What is meant to be explained in Figure 7 is not clear. Electric power generation is obtained from the plant and from the proposed system. The figure caption should be corrected. Font sizes should be considered.

Response:

Thanks to this comment, Figure 7 caption is corrected.

 

 

14. What exactly does Figure 8 show? The Y-axis title is missing. The graphics are a little messy. It should be replaced with another chart type.

Response:

Thanks to this comment, Figure 8 is improved. Also, the data of Figure 8 is in the Table 3.

 

15. Tables 4 and 5 should be fitted to the format.

Response:

Thanks to this comment, both tables are re-checked.

 

16. Figures 9 and 10 are not proper graphs. It should be replaced with another chart type.

Response:

Thanks to this comment; these figures with present chart type, were provided as they are due to another reviewer’s comments in the first round of revision. Hence the authors would not have permission to change them again to another chart type anymore.

 

17. The two tables in Table 7 should be properly combined into one table.

Response:

Thanks to this comment, both tables are merged together.

 

18. What is meant to be explained in Figure 11 is not entirely clear. Electric power generation is obtained from the utility and from the proposed system. The figure caption should be corrected for better understanding.

Response:

Thanks to this comment, Figure 11 caption is edited.

 

19. What exactly does Figure 12 show? The Y-axis title is missing. The graphics are a little confusing. It should be replaced with another chart type.

Response:

Thanks to this comment, Figure 12 is improved. Also, the data of Figure 12 is in the Table 7.

 

20. Tables 8, 9, 10, and 11 should be fitted to the format.

Response:

Thanks to this comment, the mentioned tables are re-checked.

 

21. Figures 13, 14, and 14 are not clear graphs. They should be replaced with another chart type.

Response:

Thanks to this comment; as it was said, these figures with present chart type, were provided as they are due to other reviewer’s comments in the first round of revision.

 

22. Section 3.5 should be bold. The text below should not be in bold.

Response:

Thanks to this comment, section “3.5. Financial Sustainability” is bolded.

 

23. Figures 16, 17, 18, and 19 should be presented with a more appropriate graph. It's not clear what it means. The Y-axis title is missing.

Response:

Thanks to this comment, the mentioned figures are re-checked. Now, they have Y-axis title.

 

24. Conclusion section should be written according to the results obtained from the study. This is not done here. It must be rewritten.

Response:

Thanks to this comment, Conclusion is improved.

Author Response File: Author Response.pdf