An approach to increase the power output of Karnafuli Hydroelectric Power Station: A step to sustainable development in Bangladesh’s energy sector

Renewable energy has become the most prominent source of energy to reduce carbon emissions around the globe. Undoubtedly, hydro energy is very much clean energy among other sources. In Bangladesh, hydro energy is available only in a specific southern area contributing several hundred megawatts to the national grid. This paper devotes to assessing the capacity and practicability of a hydropower plant to boost the power output by implementing the combined cycle hydropower system. The proposed method has been developed by 1) studying the existing plant based on surveyed data, 2) selecting the site for installing the hydrokinetic turbine, 3) designing with consideration of numerous constraints of inter dependability, and 4) creating a prototype model to ensure the practicability. Preliminary results show that a significant amount of additional electric energy can be generated from the plant with higher efficiency.

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Addressed:
Thank you for the comment. It was a typo, sorry. It will be Table-3. We have corrected it.
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The supporting information that presented in the manuscript were the same Figures and Tables in the manuscript. Therefore, no additional data or information remains. We have omitted this part from the manuscript.
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Reviewer #1: No
Reviewer #2: Yes Ans: Thank you for comments. We have rewritten the manuscript thoroughly and added more sections to present in more readable form. We added subsection 1.1 in page-2 under the title of related works and Motivation.

Review Comments to the Author
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Reviewer #1:
The first and general comment relates to the written form, as the paper requires a serious improvement in English grammar and spelling. The English should be improved. A deep proofreading is needed, many errors can be seen through the document.
Addressed: Thank you for your comment. We have checked the manuscript thoroughly and try to improve the writing. The proofread has performed in peer.
ii)The introduction and the related review of the literature is poor provided. And the structure must be improved for a better understanding of the current state of the art. Also, the drawbacks of the existing methods must be highlighted clearly for justifying the upgrade proposed by the current work. The way the latter work is improving the state of the art must be clarified.

Address: We have rewritten the Introduction section.
We added an extra subsection named "1.1 Related works and Motivation" under the Introduction Section on page-2, in line-40. We have rearranged the structure of the manuscript so that it may understandable more.
iii) Novelty of the paper is not mentioned obviously. There're a grammatical and syntax errors.
Address: Thank you for the comments. We have rewritten the Introduction section so that the novelty of this work is focused. All grammatical and syntax errors are revised in a peer review process. The motivation subsection in line-40 may display the novelty of our proposed method. We have added 12 more recent papers and sited them to show the novelty of our work. iv) Authors are encouraged to introduce a nomenclature section at the beginning of the manuscript, including all variables, acronyms, indexes and constants defined in the manuscript, in order to make the text more clear and readable.

Address: Thank you so much for the comments. A nomenclature in item formatted has been introduced in Section-3 from lines 186-203.
v) In the introduction section, the authors need more to introduce the previous literature. A comprehensive paper needs more than 40 references at least.  Fig-1, Fig-5, Fig-6, Fig-8, Fig-9, and  Fig-10. vii) Authors must be talk about the future work and potential limitations briefly in the Conclusions and Recommendations section.
Address: Thank you for the comments. We have changed the section name from "Conclusions" to "Conclusion and Recommendations". We added future scope from lines 463-472.
viii) Variables in the text must be italic.
Address: All variables in the manuscript are changed to italic form.
iX) All those comments are unfortunate when we see the quality of the numerical results. Via those results, the proposed method demonstrates its effectiveness without any doubt. However, the materials for introducing the state of the art and the methodology is deficient and poor.
Address: Thank you for the comment. We have tried our best to reflect the state of the art by rewriting the introduction section, adding the nomenclatures of different variables, redrawing some figures and citing 12 more papers. Fig-1, Fig-8, Fig-10  Step to Sustainable Development in Bangladesh"s Energy Sector Although it was felt that your manuscript was quite interesting. The main problems with the paper are as follow: 1-First paragraph of the introduction needs to be rewritten. (You can omit this paragraph)