Review Reports - Arid AREAS Water-Piled Photovoltaic Prevents Evaporation Effects Research

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

1. The abstract requires revision. It is necessary to add the relevance of the study, the purpose of the study.

2. In the Introduction, there is a lack of an overview of similar approaches to installing PV modules above the surface of water bodies. There is already enough research in the field of aquavoltaics, which discusses both the layout of photovoltaic modules above the surface of the water, and the change in the characteristics of the aquatic environment below them. It is necessary to indicate the advantages and disadvantages of each of the found approaches,. and based on the gap in existing knowledge, to formulate the purpose of the study.

2.1.1. Analysis of solar energy resources at the test site should be moved to the Results part

3. Fig 3, day number 400 is which day of the year? It is necessary to make changes to the schedule, since there are 365-366 days in a year.

4. Figure 2. It is not clear from the diagram that the values for Beijing and Turpan are summed up or it is necessary to count the values from axis X. It is necessary to make changes in the designation of each region to avoid confusion.

5. Fig 1. What is the source of these figures (no link)? In addition, coordinates are indicated for these regions. The map can be deleted , it duplicates information.

6. In section 1.2. PV array inclination and azimuth only the azimuth of the modules is specified, but there is no information about the inclination angle.

7. lines 100-102: The authors write: Solar PV arrays are shown in Figure 4, and PV arrays need a certain group spacing to ensure that PV arrays are not affected by each other, as shown in Figure 5. Distance between rows of pv modules is not indicated . According to the presented figure, there will be mutual shading of the rows in the morning and evening hours.

8. Part 2. Materials and Methods describes both the mathematical model and the experimental setup. Does the next section present simulation or experiment data? How do these data relate to each other? Has the experimental study and simulation data been verified?

9. Figure 6. Water-based piled PV test diagram. The experimental setup contains only 1 PV module, and Figure 4. Schematic diagram of the aquatic PV array has several rows. Will the vaporation conditions be the same under a group as under a single module?

10. The installation of aquatic PV array requires the organization of a system for collecting electrical energy from each photovoltaic module and transmitting it to the consumer. The paper does not describe the power supply system of the PV array in the conditions of the reservoir. Also, the generation of electrical energy cannot be carried out without the presence of a consumer. It is necessary to correlate the obtained area of the PV array (27.18hm2) with the power of the consumer and indicate what kind of consumers they are near the studied reservoir.

11. It is also necessary to discuss the issue of environmental friendliness of this technical solution. The reservoir has an established ecosystem at the moment. Whether it will be damaged due to shading and changes in the conditions for the penetration of sunlight into the depths of the water, whether the animal and plant diversity of the reservoir will be damaged due to shading.

Author Response

Dear reviewer:

I want to express my gratitude for your comments and professional advice. Your input was essential to make our article more academically rigorous. We have carefully reviewed your suggestions and requests and corrected the revised manuscript. We are committed to continuous improvement and hope that our work reflects that. Please see below for the details:

Question1: the abstract requires revision. It is necessary to add the relevance of the study and the purpose of the study.

The author’s answer: We have added the following paragraph as a supplement, ‘In arid and semi-arid reservoirs, water surface evaporation is the main way of water dissipation, in order to inhibit the evaporation of water and enhance economic efficiency. The evaporation inhibition rate of water-piled PV at different times of the year is derived from the anti-evaporation test of water-piled PV, and a new idea is proposed for water conservation in plains reservoirs in arid areas’.

Question 2: In the Introduction, there is a lack of an overview of similar approaches to installing PV modules above the surface of water bodies. There is already enough research in the field of aquavoltaics, which discusses both the layout of photovoltaic modules above the surface of the water, and the change in the characteristics of the aquatic environment below them. It is necessary to indicate the advantages and disadvantages of each of the found approaches,. and based on the gap in existing knowledge, to formulate the purpose of the study.

The author’s answer: Thank you for making this comment. Less research has been conducted on piled Photovoltaic (PPV), which are commonly used in fishponds, small reservoirs, and lakes for aquaculture. In comparison, more research has been focused on floating photovoltaic (FPV) that is suitable for areas with deeper water depths. In this article, we provide a basic outline of the installation process for PPV as follows:

Waterborne Photovoltaics (WPV) is divided into floating Photovoltaic (FPV) and pile-based Photovoltaic (PPV), and water-based pile-based PV is mainly applied in areas where the water depth does not exceed 3 m. Prefabricated pipe pile-type concrete is used as the pile foundation, suitable for small lakes, rivers, reservoirs, artificial fish ponds, and other environments.

qustion2.1.1:Analysis of solar energy resources at the test site should be moved to the Results part.

The author’s answer: We've put the part of the question in the results section and deleted the picture about location.

question3: Fig 3, day number 400 is which day of the year? It is necessary to make changes to the schedule since there are 365-366 days in a year.

Question4: Figure 2. It is not clear from the diagram that the values for Beijing and Turpan are summed up or it is necessary to count the values from axis X. It is necessary to make changes in the designation of each region to avoid confusion.

The author’s answer: For question 3, we have changed the horizontal axis to 365 days. In response to question 4, we have redrawn the graph to make it look more intuitive.

Fig 3 Comparison of the total annual average horizontal solar radiation between Turpan and Beijing

Fig 4 Daily variation curves of solar radiation in Turpan and Beijing

Question5: Fig 1. What is the source of these figures (no link)? In addition, coordinates are indicated for these regions. The map can be deleted. It duplicates information.

The author’s answer: Thank you for your advice. the picture has been deleted.

Question 6: In section 1.2. PV array inclination and azimuth only the azimuth of the modules is specified, but there is no information about the inclination angle.

The author’s answer: in response to your suggestion, we have added the relevant explanatory notes to the text and replaced the images as follows:

According to the photovoltaic system design aid software PVsyst, the optimal tilt angle for installing a photovoltaic system in this area is 36⁰, based on the principle of obtaining the minimum loss of solar radiation.

Question 8: Part 2. Materials and Methods describes both the mathematical model and the experimental setup. Does the next section present simulation or experiment data? How do these data relate to each other? Has the experimental study and simulation data been verified?

The author’s answer: we used our own experimental data to calculate the benefits of evaporation, using Dalton's model as the foundation for our computations.

Question 9：Figure 6. Water-based piled PV test diagram. The experimental setup contains only 1 PV module, and Figure 4. Schematic diagram of the aquatic PV array has several rows. Will the vaporation conditions be the same under a group as under a single module?

The author’s answer: Thank you for your advice on this issue. This test was conducted under hydrostatic conditions on land. Only one photovoltaic unit was used, instead of multiple units covering a large area of the reservoir. The objective of this test was to demonstrate that the Photovoltaic Panels (PPV) can help with water evaporation and conservation, and can provide a good return. Further tests will be conducted to verify the effectiveness of the PPV on larger bodies of water.

Question 10: The installation of aquatic PV array requires the organization of a system for collecting electrical energy from each photovoltaic module and transmitting it to the consumer. The paper does not describe the power supply system of the PV array in the conditions of the reservoir. Also, the generation of electrical energy cannot be carried out without the presence of a consumer. It is necessary to correlate the obtained area of the PV array (27.18hm2) with the power of the consumer and indicate what kind of consumers they are near the studied reservoir.

The author’s answer: we have rewritten this section as follows, and thank you for your suggestions. According to line 275 of the text, it appears that the primary purpose of the application is suggested.

It is possible to calculate the economic benefits of water savings due to PV power generation and panel covering. Figure 10 shows a PPV system based on reservoir. The specific parameters are shown in Table 1:

Fig 10 System Diagram for PPV

Based on the figure provided, the PV system produces DC power that can be utilized by DC loads, stored in batteries, or converted to AC power through an inverter for use by AC loads or a gas turbine. The PV panels used in the test have a power output of 160w. With the coverage area shown in Table 1, a total of 388,285 PV panels can be installed. Each PV panel can generate 0.6 kwh of power per day (without considering losses from the inverter and other factors). This results in a daily power generation of 232,971Kwh, which translates to a revenue of 144,442RMB per day.

Question 11: It is also necessary to discuss the issue of environmental friendliness of this technical solution. The reservoir has an established ecosystem at the moment. Whether it will be damaged due to shading and changes in the conditions for the penetration of sunlight into the depths of the water, whether the animal and plant diversity of the reservoir will be damaged due to shading.

The author’s answer: I appreciate your interest in this matter,in the manuscript, your question is addressed in lines 309-318.

Thank you very much for your attention and time. I am looking forward to hearing from you.

Yours sincerely.

JiaMing Huang

September 27, 2023

Email: H2842928692@outlook.com

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Dear authors, during the review process the following comments and questions were identified:

1. It is necessary to carefully double-check the formatting of the article:

references to sources are formatted incorrectly; there are repetitions of sentences (lines 30-34); The drawings are labeled incorrectly.

2. The introduction is weak and needs improvement.

3. Punts 1.1. and 1.2. must be moved to section 2.

4. It is necessary to indicate the source of information from where the data on solar radiation was taken in paragraph 1.1.

5. What installation angle do the panels require?

6. Line 113 states that Dalton's method is most appropriate. Why? What is its advantage compared to other methods? It is necessary to provide links to sources where the listed methods are presented.

7. It is necessary to provide a block diagram, as well as an electrical diagram of the installation.

8. What kind of load does the photovoltaic panels supply?

9. How will the panels be cleaned from dust? When the surface is dusty, electricity generation is significantly reduced.

10. What type of panels will be used? It is necessary to make the panels moisture-proof.

Author Response

Dear reviewer:

Comment 1：It is necessary to carefully double-check the formatting of the article:

references to sources are formatted incorrectly; there are repetitions of sentences (lines 30-34); The drawings are labeled incorrectly.

The author’s answer: I have made changes based on your suggestions to address the issues mentioned above.

Comment 2：The introduction is weak and needs improvement.

The author’s answer: Thank you so much for sharing your thoughts on the article. I really appreciate it! I made sure to include the points you mentioned. You can locate my modifications in lines 58 through 82 of the article.

Reducing water evaporation is a significant issue, particularly in arid and semi-arid regions. Various methods have been proposed to address this concern, including utilizing palm fronds to cover the water surface. Full coverage of the water surface can reduce evaporation by up to 55%, while semi-coverage can decrease it by 26%^[7]. Benzene sheets and other physical materials have also been tested for their efficacy in reducing evaporation rates. Results have shown that the more extensive the coverage, the more significant the reduction in evaporation^[8]. Furthermore, studies have been conducted to examine the impact of land photovoltaic installation on evaporation. It has been observed that concentrated lighting reduces evaporation by 21%, while uniform lighting results in a 14% reduction. In contrast, no coverage leads to a 19% reduction in evaporation^[9]. Currently, only a limited number of scholars have delved into the effects of FPV. Certain researchers have examined its influence on watersheds and formulated a mathematical model. Their findings indicate that as the coverage of FPV expands, so does the effectiveness of water conservation ^[10]. The installation of FPV in arid region reservoirs can increase power generation capacity by 58%, synergizing hydroelectric and photovoltaic power generation^{[11, 12]}. However, the studies mentioned above are solely based on theoretical models and have not been tested in the field. This raises concerns about the validity of the model as the installation environment and orientation of the reservoir can vary in different regions. Therefore, it is necessary to conduct field tests to verify the effectiveness of the model in real-world scenarios.

Comment 3: Punts 1.1. and 1.2. must be moved to section 2.

The author’s answer: I have made the changes you suggested, which can be found at line 103 of the manuscript.

Comment 4: It is necessary to indicate the source of information from where the data on solar radiation was taken in paragraph 1.1.

The author’s answer: Thanks for the advice, I use Meteonorm software to get my weather information. Meteonorm is a tool that provides information on rainfall, solar radiation, and more for a specific area.( Lines 106-107 of the manuscript)

Comment 5:What installation angle do the panels require?

The author’s answer: Thank you so much for sharing your suggestion with me! I've gone ahead and added the item you mentioned. In the first draft, I actually wrote about the angle and spacing of the PV panels, but I later realized that it was already covered in the existing content, so I removed it. Thanks again for your input!( Lines 136-146 of the manuscript)

The time zone where the test site is located is East 8, and the shadows were modeled by Sketchup software, which allows for a group spacing of 2m.

The test site is located in the northern hemisphere, and in order to maximize solar radiation, the PV array is fixed to face south. According to the photovoltaic system design aid software PVsyst, the optimal tilt angle for installing a photovoltaic system in this area is 36⁰, based on the principle of obtaining the minimum loss of solar radiation.

Comment 6: Line 113 states that Dalton's method is most appropriate. Why? What is its advantage compared to other methods? It is necessary to provide links to sources where the listed methods are presented.

The author’s answer: Measuring evapotranspiration in lakes and reservoirs is crucial for managing water balance in arid and semi-arid regions. The Dalton model, which is used to estimate evapotranspiration in open spaces, has a smaller error rate according to studies [19-21].( The manuscript has some changes in lines 152-156.)

Comment 7: It is necessary to provide a block diagram as well as an electrical diagram of the installation.

The author’s answer: Thank you for this suggestion, I have added the electrical diagrams of the PPV installation to the manuscript as follows(which can be found in lines 333-349 of the manuscript):

Based on the information provided about the project area, the reservoir has a total area of 31.6 hectares, making it a small irrigation-type reservoir. If the reservoir were completely covered with photovoltaic panels, it would be possible to calculate the economic benefits of water savings due to PV power generation and panel covering. Figure 10 shows a PPV system based on a reservoir.

Based on the figure provided, the PV system produces DC power that can be utilized by DC loads, stored in batteries, or converted to AC power through an inverter for use by AC loads or a gas turbine. The PV panels used in the test have a power output of 160w. With the coverage area shown in Table 1, a total of 388,285 PV panels can be installed. The photovoltaic panel used in the test was manufactured by Hunan Advanced Technology Co Ltd, model GHGN-150WDJBZ; each PV panel can generate 0.6Kwh of power per day (without considering losses from the inverter and other factors). This results in a daily power generation of 232,971Kwh, which translates to a revenue of 144,442RMB per day.

Comment 8: What kind of load does the photovoltaic panels supply?

The author’s answer: Dear reviewer, I wanted to share my main objective which is to reduce evaporation of water bodies by installing pile-based photovoltaic systems. These systems can directly supply power to DC loads and batteries for storage, or can be converted from DC to AC using an inverter to power AC loads. This information is addressed in Comment 7.

Comment 9 : How will the panels be cleaned from dust? When the surface is dusty, electricity generation is significantly reduced.

Comment 10：What type of panels will be used? It is necessary to make the panels moisture-proof.

The author’s answer: thank you for your suggestion, the type of PV panels selected has been added in comment 7; the answer to how to clean and protect photovoltaic panels from moisture can be found below.( Lines 419-425 in the manuscript)

To ensure the durability of photovoltaic panels, the outer layer is sealed with toughened glass. To prevent moisture from seeping in, it is important to properly treat the location of the junction box and wiring. With proper treatment, the panels can be directly cleaned with water, making it easier and more cost-effective to maintain them. In the future, there will be research carried out on self-cleaning photovoltaic systems.

Thank you very much for your attention and time. I am looking forward to hearing from you.

Yours sincerely.

JiaMing Huang

September 27, 2023

Email: H2842928692@outlook.com

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Review report

Journal Name:	Water (ISSN 2073-4441)
Manuscript Number:	water-2611684
Title of the Manuscript:	Arid areas water piled Photovoltaic prevents evaporation effects research
Type of the Article	Original Research Article

Reviewer comment:

This is an interesting paper for arid areas where the higher ambient temperature is a major problem. In this research paper author presents the anti-evaporation effect of the water body was studied on water pile photovoltaic, mainly on water body water temperature and PV module temperature. The following comments/observations may be noted:

1. The novelty/originality shall be justified by highlighting that the manuscript contains sufficient contributions to the new body of knowledge.

2. Research gaps should be delivered in a more clear way with the directed necessity for the conducted research work.

3. The objective, methodology, and results should be better described, discussed, and justified.
You don't include the uncertainty analysis in the text or in any of your figures. Error bars should be included when appropriate.

4. The nomenclature symbols (Latin symbols, Greek symbols, subscripts, and superscripts) and abbreviations list are not explained correctly.

5. It is important to compare this development method with another theoretical or experimental method under actual conditions to present the actual improvement in your study.

6. All the symbols that appeared in the manuscript should be explained.
The conclusion points are not clear and too long, it must be re-written.

7. The conclusion section is missing some perspectives related to future research work.

8. There are too many grammatical errors and inadequate expressions. The quality of the language in the manuscript needs to improve.

Therefore, the paper is revised accordingly and the present form is not acceptable in Water.

Comments for author File: Comments.pdf

Comments on the Quality of English Language

Author Response

Dear reviewer:

Comment 1： the novelty/originality shall be justified by highlighting that the manuscript contains sufficient contributions to the new body of knowledge.

In arid and semi-arid reservoirs, water surface evaporation is the main way of water dissipation in order to inhibit the evaporation of water and enhance economic efficiency. The evaporation inhibition rate of water-piled PV at different times of the year is derived from the anti-evaporation test of water-piled PV, and a new idea is proposed for water conservation in plains reservoirs in arid areas.

The author’s answer: Thanks to your comments, I have reintroduced the background of my study in the abstract section, as well as the purpose of my study.(This modification can be found in 9-14 of the manuscript.)

(1) Background: In arid and semi-arid reservoirs, water surface evaporation is the main way of water dissipation in order to inhibit the evaporation of water and enhance economic efficiency. The evaporation inhibition rate of water-piled PV at different times of the year is derived from the anti-evaporation test of water-piled PV, and a new idea is proposed for water conservation in plains reservoirs in arid areas.

Comment 2: Research gaps should be delivered in a more precise way with the directed necessity for the conducted research work.

The author’s answer: Thanks to your suggestion, I have added research related to preventing water evaporation and waterborne photovoltaics in the introduction to draw out the purpose of my research. ( This modification can be found in manuscript 58-101)

Floating Photovoltaic (FPV) has been found to be an effective solution for reducing evaporation from water bodies. The rate of evaporation is influenced by temperature and inversely proportional to humidity levels. Adjusting the tilt angle of PV can also significantly reduce evaporation, leading to an 11% increase in annual power generation when a single-axis tracking device is used^{[13, 14]}. Despite the effectiveness of FPV, no relevant experiments have been conducted for Waterborne Photovoltaic (WPV), which holds practical and economic value in fishery-photovoltaic complementary fish ponds. In this study, we have analyzed and organized the results of experiments conducted on WPV. However, the mechanism of evaporation inhibition at different times has not been elaborated upon. This paper focuses on several research topics. Firstly, it aims to create a prototype observation model test. Then, it examines the primary factors that affect the temperature of water bodies due to PV panels, including the formation of saturated water vapor pressure difference and the day-to-day change process. Additionally, it briefly analyzes the evaporation inhibition rate of WPV on water bodies. Lastly, the paper explores the economic benefits of water saving with WPV technology.

Comment 3： The objective, methodology, and results should be better described, discussed, and justified. You don't include the uncertainty analysis in the text or in any of your figures. Error bars should be included when appropriate.

The author’s answer: Dear reviewer, thank you for your suggestion. I have utilized the method of comparing and analyzing errors. The revised manuscript is as follows (Corrections can be found in lines 234-241,319-333 of the manuscript):

Fig 5 Daily variation of evaporators A, B and atmospheric temperature

Fig 6 Schematic diagram of temperature change of each component

(1) Based on the information presented in Figure 5, it can be inferred that the A evaporator has more concentrated water temperature than the B evaporator, and there is a significant temperature difference between morning and evening atmospheric temperatures. The temperature in the atmosphere increases slowly after 8:00 a.m. The temperature of both evaporators is lower than that of the atmosphere, with Evaporator A exhibiting the lowest water temperature due to the shading provided by photovoltaic panels.

(2) Figure 9 presents a detailed depiction of the evaporation process for A and B evaporators. The diagram showcases the monthly evaporation rates for both evaporators in the upper section. It highlights the difference between the monthly evaporation and the evaporation inhibition rates of A and B in the lower section.

The diagram shows that the A evaporator has a more concentrated and consistent monthly evaporation rate than the B evaporator, which is more prone to fluctuations caused by air temperature and wind speed. During the winter season, both A and B evaporators have similar evaporation rates due to the water surface freezing, and the photovoltaic panels have minimal impact on the evaporation process. The chart indicates that both A and B evaporators experience an increasing trend in evaporation volume, followed by a decreasing trend, with the maximum volume reached in July. An evaporator has a total evaporation volume of 221mm, while B evaporator has an evaporation volume of 370mm.

Fig 9 Evaporation and evaporation suppression rate under PV panel shading

Comment 4: the nomenclature symbols (Latin symbols, Greek symbols, subscripts, and superscripts) and abbreviations list are not explained correctly.

The author’s answer : Sincere greetings. I have done my best to correct any symbol problems in the manuscript. Please let me know if you find any other errors.

Comment 5: It is important to compare this development method with another theoretical or experimental method under actual conditions to present the actual improvement in your study.

The author’s answer :dear reviewer. I wanted to share my thoughts on the research gap regarding the anti-evaporation effect of pile-based PV on water. Currently, most research has focused on floating PV instead. Theoretical research mainly aims to prove the accuracy of different methods for measuring evaporation. However, This manuscript was written to prove that water pile-based PV has a favorable anti-evaporation effect and can generate a good profit. I would love to hear your thoughts and feedback on my viewpoint. Thank you for your guidance and for taking the time to review my paper. Best regards.

Comment 6: All the symbols that appeared in the manuscript should be explained.
The conclusion points are not clear and too long, it must be re-written.

The author’s answer : Dear reviewer, I have rewritten the results section to show that the trial was successful.( Lines 464-479 in the manuscript)

Based on the test conducted, it was observed that the water temperature in evaporator A was significantly lower than that of evaporator B and the atmospheric temperature. During summer, the maximum evaporation inhibition rate reached 40.16%, while the lowest rate was 12.14% during winter. On average, the evaporation inhibition rate for the entire year was 29.3%. Furthermore, the economic benefits of preventing water evaporation using water pile-based PV were analyzed. If the water body's evaporation is used for agricultural irrigation, it can cover an area of 38hm². On the other hand, if it's used for drinking water, it can generate a revenue of 30,000RMB.

These test results indicate that the PV module blocks most of the solar radiation and that water pile-based PV can effectively reduce the water body's temperature, ultimately reducing the rate of evaporation. During summer, PPV had the highest evaporation inhibition rate, which was slightly lower during winter. Overall, the use of PPV in arid and semi-arid areas can help conserve water and produce good economic benefits.

Comment 7: The conclusion section is missing some perspectives related to future research work.

The author’s answer :In my discussion, I delve into what areas could use further exploration in the future, while pointing out where current research could improve and discussing any recent advancements ( Lines 402-449 in the manuscript).The following is the discussion section

Land-based photovoltaics face the problems of extensive land area, wind and sand, and difficulty in cleaning^{[28, 29]}, and the development of Waterborne Photovoltaics can effectively alleviate the increasingly tight land resources.

It has been found that using waterborne photovoltaic systems can effectively decrease water evaporation while increasing the power generation capacity^{[11, 30]}. The principle of reducing water evaporation lies in the fact that PV panels block direct solar radiation and thus reduce the water surface temperature, which has been verified by different experimental and theoretical approaches^{[25, 31]}. However, the research mentioned above approaches did not systematically analyze the temperature of different layers of the water body, and future research directions could be biased towards the continuous effect of water photovoltaic systems on the stratification effect of water temperature in large water bodies under different seasons. The above studies are based on floating photovoltaic systems but not on pile-based photovoltaic systems. Water-piled photovoltaic has a better spatial effect; the upper layer can implement photovoltaic power generation project, and the water surface can be combined with an anti-evaporation floating ball ^[32], which can achieve a better effect of preventing the evaporation of the water body, which has essential research value for arid areas.

In rural areas, an emerging trend is the combination of fishery and photovoltaic systems to generate additional income. By leveraging fish's distinct habits and ability to adjust to water temperatures, a layered aquaculture approach can be achieved in water bodies. Studies have shown that installing aquatic photovoltaic systems on fish ponds can bring significant economic gains^{[33, 34]}, particularly in implementing this technology within desert regions; it has proven to be effective in addressing concerns surrounding aquaculture in arid areas, mitigating water body evaporation, and providing supplementary benefits^[35], but insufficient research exists regarding the integration of waterborne photovoltaics and aquaculture. Further exploration is necessary to establish effective farming techniques and management practices incorporating waterborne photovoltaics. This is attributed to the impact that waterborne photovoltaics may have on water temperature, which can adversely influence the ability of diverse fish species to flourish in the water column. To ensure the durability of photovoltaic panels, the outer layer is sealed with toughened glass. To prevent moisture from seeping in, it is important to properly treat the location of the junction box and wiring. With proper treatment, the panels can be directly cleaned with water, making it easier and more cost-effective to maintain them. In the future, there will be research carried out on self-cleaning photovoltaic systems.

Research has indicated that the implementation of aquatic photovoltaic systems yields a substantial carbon reduction effect, resulting in the reduction of emissions by an impressive 3.3 million tons annually^[14]. It can reduce the eutrophication of water bodies and reduce the concentration of chlorophyll and nitrate in water bodies ^{[36, 37]}. However, the method mentioned above does not entirely cover vast water surfaces, and some research is relatively uniform with a limited observation duration. As the deployment of solar photovoltaic panels is regional and spatial, diverse areas may have varying inclinations and outcomes based on different arrangements and densities, which have not been adequately explored. To investigate the influence of water-based photovoltaic installations on water quality under distinct conditions, further research can examine the placement and spacing of photovoltaic arrays in sizeable water bodies.

This study examines the anti-evaporation effect of PPV. The findings indicate that these devices can effectively lower water temperature and reduce evaporation. However, the study only used model tests, and further research is needed to test the impact of pile photovoltaics installed at different heights and changes in water quality. Future research can explore these areas to broaden our understanding of this technology.

Commnt 8: there are too many grammatical errors and inadequate expressions. The quality of the language in the manuscript needs to improve.

The author’s answer: dear reviewer, I have made major revisions to my article. Thank you for your advice!

Thank you very much for your attention and time. I am looking forward to hearing from you.

Yours sincerely.

JiaMing Huang

September 30, 2023

Email: H2842928692@outlook.com

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

Dear author,

You have done a good job of improving the quality of the manuscript.

Author Response

Dear reviewer
Thank you for taking your time; your comments on the manuscript are much appreciated!
I look forward to hearing from you!

Best Wishes

JiaMin Hunag

Email address: H2842928692@outlook.com

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The author incorporated all the suggestions into the revised manuscript. I would recommend the article in its present form in the Water Journal.

Comments on the Quality of English Language

Minor editing of English language is required in the manuscript.

Author Response

Dear reviewer
Thank you for taking your time; your comments on the manuscript are much appreciated!
I look forward to hearing from you!

Best Wishes

JiaMin Huang

Email address: H2842928692@outlook.com

Author Response File: Author Response.pdf