Integration of Solar Photovoltaic Plant in the Eastern Sumba Microgrid Using Unit Commitment Optimization
, Ngapuli I. Sinisuka 1, Vincent Debusschere 2, Deddy P. Koesrindartoto 3 and Muhammad Yasirroni 4Round 1
Reviewer 1 Report (Previous Reviewer 2)
Comments and Suggestions for AuthorsLiterature review portion needs to be revised: needs to discuss the drawbacks of previously proposed techniques similar to those used to solve this problem.
Need to discuss the importance in terms of the contribution and novelty of this proposed technique.
Abbreviation table is required to be included
Discuss solar PV modeling in cost function (objective function)??
This phrase needs further elaboration; please discuss the criteria based on which it will be decided “Demand response (DR) in this research proposes a peak load shifting mechanism from one peak load period to another.”
Comments on the Quality of English Language
Minor editing of English language required
Author Response
Based on the results of the review, I have made improvements to the reviewer's suggestions and corrections, especially regarding the novelty presented in the paper. I hope this correction is clear enough and my writing meets the requirements.
Author Response File: 
Author Response.pdf
Reviewer 2 Report (Previous Reviewer 3)
Comments and Suggestions for AuthorsThe paper addresses the integration of a solar PV plant in Eastern Sumba microgrid. The overall quality of the paper has been improved compared to the previous submission. However, some points still need to be addressed:
1. Ensure that all acronyms have been introduced only once in the paper.
2. Please replace "solar insulation" in line 167 with "solar irradiance".
3. Please avoid the first person in the text, e.g. "we" in line 305. Instead "the authors" could be used.
4. Please check Table 1, as there are some empty cells which shall not be there. Also, align the labels used in Figure 2 with the labels used in Table 1.
5. What SW has been used for the simulation work? The parameters of the electrical network that has been simulated are missing.
Comments on the Quality of English LanguageQuality of English is fine, only some minor adjustments are required. Proof reading is required in order to correct any remaining typo.
Author Response
According to the results of the review, I have made improvements to the reviewer's suggestions and corrections, especially in the mention of acronyms, correcting several words, and alignment between Table 1 and Figure 2 in the paper. I hope this correction is clear enough and my writing meets the requirements.
Author Response File: Author Response.pdf
Reviewer 3 Report (Previous Reviewer 1)
Comments and Suggestions for AuthorsThis paper presents unit commitment based on priority list and genetic algorithm and performs financial study on a solar power plant in Indonesia.
Please format Table 1 properly.
Is the data presented in Figure 4 the "average" hourly output power of the solar plant?
Unit commitment based on priority list and genetic algorithm are well-established methods. Clearly highlight the "improvements" or novel contribution of your methods and compare them with the literature.
What simulation platform were used for the analysis?
Financial feasibility is added in the theory section, but the calculations for payback period are missing.
Comments on the Quality of English LanguageComprehensive proofreading is required. There are several grammar errors in the paper.
Author Response
According to the results of the review, I have made improvements to the reviewer's suggestions and corrections, especially in the explanation of the novelty of the writing and improvements in Table 1, and corrected some of the wording in the paper. I hope this correction is clear enough and my writing meets the requirements.
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report (Previous Reviewer 3)
Comments and Suggestions for AuthorsMost of my comments have been addressed properly. I only have 2 observations left:
1. I suggested to replace "we" with "the authors". This has not been done on line 430.
2. The parameters of the electrical system have not been given. It is impossible for anyone else to reproduce the results of the power flow, and of the paper in general, without electrical data. Please include the data in the final version of the paper.
Comments on the Quality of English LanguageQuality of language is fine.
Author Response
A revision has been made, changing "we" to "authors" and explaining the electricity network parameters in the simulation which have been included in the m-file that accompanied the main simulation program
Author Response File: Author Response.pdf
Reviewer 3 Report (Previous Reviewer 1)
Comments and Suggestions for AuthorsAuthors have improved the equality of the paper. I have a couple of minor comments:
Figure 7 needs to be further explained. It is not clear what is shown in this figure. What does load+PV mean? The figure' legend and its captions should be self explanatory.
Discussion section should be further expanded to discuss the results of different scenarios simulated in the paper.
Comma at the end of some questions should be changed to dot.
Author Response
A detailed explanation of Figure 7 has been added.
The discussion section has been expanded to discuss the entire optimization process, starting from the results of the PL-GA algorithm with improved mechanisms and also multi-state optimization techniques consisting of Netload, DR mechanism, BESS optimization, and PL-GA algorithm can optimize the UC scheme on the integration of Solar PV paired with BESS with existing microgrid power system.
The commas at the end of some question sentences have been replaced with dots.
Author Response File: Author Response.pdf
This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThe paper investigates a hybrid PL-GA optimization algorithm for unit commitment in a microgrid with solar PV and diesel units.
Here are my comments:
1. Please use consistent abbreviation explanation in terms of capitalization, e.g. Priority list (PL) vs. dynamic programming (DP)
2. The extent of the literature review in the paper seems to be limited to the following two paragraphs. I feel that the literature review in the introduction is not comprehensive and the research gap is missing.
"Many countries have launched financial incentive programs to promote the adoption of RES. In 2018, Vu Ba Hau et al. determined the financial benefit for microgrids of the incentives and tax benefits regarding integrating RE generation [8]. This initiative is further supported by the 2022 Glasgow Climate Pact which set out a commitment to implement programs to support the implementation of RES via enforcing incentives, tax deductions, and tax benefits [9, 10].
Solving the UC using a GA that began with a Lambda iteration algorithm to obtain initial populations was studied in [14], which led to a UC solution obtained using an improved PL and GA. In the UC problem, the PL-GA is used to find the initial population and the Lambda iteration technique for the lowest operating cost convergence for ED. Several improvements are still possible in the presented research (using the PL-GA algorithm). For example, the PL-GA and Lambda solution may suffer local optima [16]. In 2019 Sarjiya explored a hybrid genetic algorithm-based priority list (GABPL) optimization technique, with a UC stage with a GA-based PL algorithm to generate population initials and continued with GA and the ED stage individual evaluation process using Lagrange. This method produces a good quality solution with a long convergence time [6]. Also, the improved PL method may be more suitable for small and simple electrical systems [17]."
3. Figure 1 needs more explanation for the symbols and parameters used in the picture.
Also,
generator units -> generation units
power balanced -> power balance
4. Term "where" after equations does not need indentation.
Also, indentation format in the paper is inconsistent.
5. All parameters should be italicized. Some are missing. (e.g. line 105)
6. Equation 16 and how to find the parameters need more explanation
For equation 21 parameters should be explained.
7. Figure 2 and Table 3 (and all figures and tables) should appear AFTER they are cited in the text not before.
8. Table 1 can be presented in a better format, maybe by reversing columns and rows.
9. Only one load profile is provided for the island. Usually monthly or seasonal profiles are needed for a more accurate analysis. The same applies for the solar panel output which varies from season to season. Please add an explanation.
10. For the solar panel, the BESS info and MPPT and charge control algorithm info are missing.
11. "hybrid PL-GA" is not a new concept. This paper seems to be just implementation of a known algorithm and comparing it with a couple others for a specific microgrid. Better literature review and explanation of novelty of the work compared to the literature (some listed here) are expected.
The State of Art in Particle Swarm Optimization Based Unit Commitment: A Review
Integration Method of Unit Commitment Using PL-GA Binary Dispatch Algorithm for Intermittent RES in Isolated Microgrids System
PSO Based Dispatch and Control of Hybrid Power System with PV-Diesel Generator- A Prototype
Review on the cost optimization of microgrids via particle swarm optimization
12. The "Net Load" concept is a well-established method in the literature and is not a novel concept. This needs to be explained more clearly with proper citations such as (or other references):
Netload-constrained Unit Commitment Considering Increasing Renewable Energy Penetration Levels: Impact of Generation Schedules and Operational Cost
Determination of Maximum Grid-Connected Photovoltaic Penetration Level Based on Unit Commitment Solution
Impacts of Variability and Uncertainty in Solar Photovoltaic Generation at Multiple Timescales
13. In the flowchart,
what is IHR?
TOC+penalty -> TOC = TOC+penalty
Yes/No should be added for all decision blocks.
The operations in the flowchart need to be further explained or referenced.
14. For figure 5, what are the main criteria for optimization. Are batteries' lifetime and cost considered?
15. In Figure 8, negative numbers in hours 2, 13, and 15 should be clarified.
16. For computational time analysis, computing platform and software or programming languages used should all be very clear.
17. More recent and credible journal publications as references need to be added.
Reviewer 2 Report
Comments and Suggestions for AuthorsGrammar and typo errors must be improved, and nglish and sentence structure must also be checked.
The abbreviation table should be included.
Line 180-181: “The demand response (DR) considered in this paper is strictly for demand load shifting, which shifts a portion of the load from one period of time to another.” Are you proposing or using any propriety setting for load shifting as this above statement is not providing any information regarding that? How would you decide which load to shift and which to not??
Any consideration for the maintenance and operation cost???
It is also recommended to implement this proposed method to any already available test systems (such as IEEE 13-bus and so on) for a more detail analysis of the proposed work and its benefits. Directly analyzing this for any other system will be misleading and not fully analyzed.
The equation for objective function??
Reviewer 3 Report
Comments and Suggestions for AuthorsThe paper addresses the integration of a solar PV plant in Eastern Sumba microgrid using Unit Commitment optimization. The topic is of interest for the scientific community, but it is also oriented towards the policy makers, even though it does not discusses any regulation/standard within the field.
The paper, in its current form is not suitable for publication and it needs to be improved in a number of ways. My main improvement points to be addressed are as follow.
1. The title is not clear, please also add the word Plant on it, i.e. "Integration of a Solar Photovoltaic Plant in the...". The same comment is valid for the first keyword of your paper.
2. several acronyms have been introduced more than once in your paper, e.g. RES, UC, SR, etc. Please introduce them only once.
3. The acronym GA-LR-GA is not clear. What is the 2nd GA standing for? In the abstract you associated it with Genetic algorithm and Lagrange. Please clarify.
4. Define the "interest rate of return" - introduced in the abstract.
5. Some sentences are missing the verb, e.g. on lines 72-74, last part of line 224, lines 313-315, or need rephrasing, e.g. on line 34 "...one of the solutions to providing..." -> "to provide...", on line 148 "refers to may refer", lines 286-288, etc. Moreover, a thorough reading of the entire paper and its abstract is required, as there are several sentences that are not clear enough.
6. The quality of some figures is not appropriate. For example, Figure 1 needs to be enlarged and the components shown on it need to be properly explained. Figure 2 shows 13 generators, but in your paper you talk about 17 generators. Also, not all bus bars are labelled.
Is the load profile shown in Figure 3 the aggregated load profile for the entire system? If yes, please write so.
Figures 4 and 5 are missing the "Yes" and "No" label on the selection branches. Figures 6, 7 and 9 need to be enlarged and their axes properly labelled, including the unit, i.e. the SOC it is not measured in MW or MW.
7. Please explain properly all quantities involved in your equations, including their units and check the scientific soundness off these equations. In some cases the equations do not make sense when checking them using the quantities' units.
What are the generating unit's status, startup status and shutdown status?
Why do you use ">>" and "<<" in equation (16)?
Explanation given on lines 173-174 is not in accordance with equation (17), and same is true for the explanation given for equation (21).
IRR and SPB have not been explained at all.
8. Please revise and explain all quantities given in Table 1. Why is IS measured in hour? How do you define the SFC?
9. The algorithms shown in Figure 4 and 5 are way too concise to be easy to understand. For example, in Figure 5, 2 of the blocks are "No charge no discharge initial population" and "No discharge initial population", but it is not clear what do they mean.
10. Consider replacing Table 2 with a Figure.
11. On line 348 you mentioned "steam generating units", but they are never mentioned again in the paper. Please explain.
12. On lines 402-403, you mentioned that computational results of the proposed are slightly larger. Which results are larger? Also, what do you mean by "precise results", as stated on line 406?
In conclusion, the paper needs several modifications and/or improvements, with careful attention shown to the scientific soundness of the equations and quantities involved. In the current form, the paper cannot be accepted for publication.
