Effects of Reflectance of Backsheets and Spacing between Cells on Photovoltaic Modules

Round 1

Reviewer 1 Report

The visible light (400 nm to 700 nm) is fully absorbed in Si cell. There is no any light reflected from the back sheet under the cell. The light is only reflected from the back sheet under the space region. However, these reflection lights are passed away from the around cells. How to increase the Isc of the cell, and how to evaluate the light intensity for increasing Isc?

The black sheet will absorb more lights than the white sheet. The temperature of different modules will be different. What are the temperatures for different modules?

The increase of space region will increase the module area, and reduce the module efficiency. The loss of module efficiency due to increase the module area shall be calculated to compare the gain of increase of absorption of back reflection of light.

The manuscript only presents the experimental results. The physical reasons for the increase of Isc from the refection of back sheet at space region shall be clearly discussed.

The thickness of the glasses and the model number (Low Iron Float Glass, Nuri-cooperation) shall be described.

 

  

Author Response

We appreciate very much your email (11-December-2021) forwarding us the reviewers' comments and your kind decision on our manuscript entitled “Effects of Reflectance of backsheets and Spacing between Cells on Photovoltaic modules”. Following your and the reviewers' constructive suggestion, we have carefully revised the manuscript. Detailed revisions and point-to-point responses to the Reviewers' comments can be found in the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

• Authors should add more relevant references in the Introduction regarding their experiment.
• I would expect that application of black backsheet will also increase the temperature and affect the Isc. Is that true or not?
• As shown in Fig. 1, the black BS is applied on the borders only, I do not understand its influence regarding the results shown in Fig. 3 and 4.
• References are not proper (e.g. 21 - no journal/book...).

Author Response

We appreciate very much your email (11-December-2021) forwarding us the reviewers' comments and your kind decision on our manuscript entitled “Effects of Reflectance of backsheets and Spacing between Cells on Photovoltaic modules”. Following your and the reviewers' constructive suggestion, we have carefully revised the manuscript. Detailed revisions and point-to-point responses to the Reviewers' comments can be found in the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

The following comments shall be revised.

1. In figure 3, for Black case, the Isc order is 2.5 mm > 1.5 mm > 0.5 mm. However, the Pmax order is 1.5 mm > 0.5 mm > 2.5 mm. The highest Isc of 2.5 mm sample has the lowest Pmax. For B/W case, the Isc order is 2.5 mm > 0.5 mm > 1.5 mm. However, the Pmax older is 0.5 mm > 1.5 mm > 2.5 mm. The highest Isc of 2.5 mm sample has the lowest Pmax. The increase of Isc is not corresponded to the increase of the Pmax. Especially, the highest Isc of 2.5 mm sample has the lowest Pmax. This is contradicted to the claim of this manuscript. For the B/W case, the Isc of 1.5 mm sample is lower than the 0.5 mm sample, which is also not reasonable due to the white area of 1.5 mm sample is much larger than the 0.5 mm sample. The authors shall explain the reasons for these contradictory results.
2. The tables shown in appendix A had no any units for each electrical parameter.

Author Response

We appreciate very much your email (22-December-2021) forwarding us the reviewers' comments and your kind decision on our manuscript entitled “Effects of Reflectance of backsheets and Spacing between Cells on Photovoltaic modules”. Following your and reviewers' constructive suggestion, we have carefully revised the manuscript. Detailed revisions and point-to-point response to the Reviewers' comments can be found below.

We expect that it would be suitable for the publication in Applied Sciences.

Author Response File: Author Response.docx

Reviewer 2 Report

As I already mentioned, the absorbance of black or white backsheet is different and can result in different temperature and so different Isc - this is my opinion.

On the other hand, there is no information on the parameters of SC used in experiment. The distribution of their parameters may also result in differences in Isc and Pmax of experimental modules.

I see the experiment too simple to show relevant results.

Author Response

We appreciate very much your email (22-December-2021) forwarding us the reviewers' comments and your kind decision on our manuscript entitled “Effects of Reflectance of backsheets and Spacing between Cells on Photovoltaic modules”. Following your and reviewers' constructive suggestion, we have carefully revised the manuscript. Detailed revisions and point-to-point response to the Reviewers' comments can be found below.

We expect that it would be suitable for the publication in Applied Sciences.

Author Response File: Author Response.docx

Round 3

Reviewer 1 Report

The response for the comment 1 shall be properly addressed in the manuscript.

 Some Pmax results with narrower gap spaces and BW backsheets show the highest number among results with wider gap spaces such as 1.5 and 2.5 mm as you commented. It is attributed to mainly FF variations, which is due to the variations of the module fabrication process.

It is very hard to control all factors to ultimately obtain ideal results during the soldering process. Furthermore, we think Isc is the representative factor for the effect of light reflection, but not Pmax.

Author Response

Dear Reviewer 1,

Thanks for your kind comments and advice.

We believe this report is the initiator for highly efficient PV  module technology using various backsheets and gaps.