Comments on abstract, title, references

Abstract:

The aim of the article is well explained and adheres to the guidelines of the journal; providing background, methods, results and conclusion. The number of keywords (6) is acceptable and within journal guidelines range for keywords. Moreover, the study findings are clear as the study declares that smaller PV modules are the optimum solution from a socio-economic standpoint for installation.

Title:

The title is informative given it displays the main method utilized in the paper and highlights it use “determination of optimal size of photovoltaic systems”.

References:

According to guidelines of the sustainability international journal (ISSN 2071-1050) the references are well-written, concise and relevant. However, according to the guidelines the journal name must be abbreviated, in the list of references the journal name is not abbreviated.

Comments on introduction/background

The topic and the known aspect of it are well presented in the introduction. The research question was clearly outlined, i.e. “the ideal module size of a photovoltaic DG installation”. The research question is fully justified given the background presented in the introduction and the author’s emphasis on “proper size of a distributed power installation”.

A general introduction was provided linking background to photovoltaic technology (PV) and distributed generation systems. Moreover, the introduction shows how the logical progression from the background to justify the determination of optimal PV system. The study then displays the gap in research and current solutions attempting to fill the gap.

Comments on methodology

The process of subject selection is thoughtfully laid out and the logic behind the methodology is introduced in the beginning paragraph of the methodology. The authors demonstrate the novelty (i.e. use of ANP-TOPSIS in photovoltaic field) and validity of their work (depending on TOPSIS method). The reliability of the study is demonstrated throughout the methodology with good information provided. The study methods are valid and reliable as they are well-known and used in many fields. The ability to replicate the study is dependent on the data input which must be acquired from the authors.

Comments on data and results

The data are well represented using figures and tables. The units and numbers are all appropriate to describe the findings. All tables and rows were correctly labelled. The text of the results section adds different features to the data. The categories were appropriately grouped. The significance of the result was demonstrated earlier in table 1 of the methodology. Larger sample size can also add to the practicality of the results. Nonetheless, the results are meaningful.

Comments on discussion and conclusions

Major parts of the methodology are restated to provide perspective to the results and a summary to the article. The statement “which seems to be the actual tendency” should add a reference to support the claim. The authors claim much earlier of the utility in using the decision-making criteria, however the results are displayed clearly and hence the aims of the paper are achieved. The authors discuss the limitation of the study freely and the conclusions are supported by the results from the study.

Overall statement:

The study utilized appropriate means and found good results to achieve its aims. The study here employed the ANP-TOPSIS method in photovoltaic field. The decision-making criteria found that small systems exhibit better socio-economic installations. The sample size should be improved. Furthermore, what constitutes an expert should be clarified in the study.

Strengths:

1. Good introduction with background, research gap and logical progression.
2. Methodology is well laid-out and explained to reader.
3. The data are well represented using figures and tables with appropriate units and numbers.

Weaknesses:

1. The ability to replicate the study is dependent on the data input which must be acquired from the authors.
2. What constitutes an expert should be clarified in the study.
3. The statement “which seems to be the actual tendency” should add a reference to support the claim (refer to line 395 of manuscript)

Minor errors:

• The first sentence appears to have a typo or grammatical error. Line 46 starts with “The For many year”. This error should be corrected.