Parameter Study of Financial Analysis for Implementing Solar Photovoltaics Structural Snow Fences

Round 1

Reviewer 1 Report

The paper presents an economic analysis of solar photovoltaics structural snow fences under different financial scenarios and parameters. A sensitivity analysis was performed to demonstrate which financial parameter has the highest impact on the cost-benefit of such systems.

Some minor comments are as follows

·       No technical details are provided on the system. For example type of PV panel, efficiency, outputs etc.

·       What is the basis for the O&M costs? Need some justification or should be supported by a reference?

·       What is the impact of climate on the estimated economic outputs?

·       The results shown in the Figures do not add any values since the data are already summarized in the Tables. These figures should be removed.  

Author Response

Reviewer 1:

The paper presents an economic analysis of solar photovoltaics structural snow fences under different financial scenarios and parameters. A sensitivity analysis was performed to demonstrate which financial parameter has the highest impact on the cost-benefit of such systems.

 Some minor comments are as follows

• No technical details are provided on the system. For example type of PV panel, efficiency, outputs etc.

Thank you for the comment! Table 6 shows the PV panel specifications, and the outputs were determined in the cost-benefit model (see [40] and [41]) given these specifications. 

• What is the basis for the O&M costs? Need some justification or should be supported by a reference?

As shown in Table 2, the total O&M cost ($0.38/W) of the PV system is the sum of the costs of “Inverter Replacement”, “Insurance Cost by Capacity”, and “O&M Annual Cost by Capacity”. The O&M cost ($1875/km) of the structural snow fence was provided by MnDOT, which is also shown in Table 2.

• What is the impact of climate on the estimated economic outputs?

The developed cost-benefit model (see [40] and [41]) can be used to determine the impact of weather/climate on the economic outputs. Some of the results, including the impacts of weather, orientation, etc., can be found from our MnDOT project report [42], which was added to the reference and mentioned in Conclusion.   

• The results shown in the Figures do not add any values since the data are already summarized in the Tables. These figures should be removed.  

Thank you for the comment! Tables 7&8 only show the mean, SD, and range, but do not include the results of all 5 samples (see the x axis of Figures 2&3). Figures 2&3, however, show all the sensitivity analysis results of all the 5 samples. So they give a whole picture of how the results of these parameters evolve.  So we decide to keep these figures.

Reviewer 2 Report

There are a number of small items that could improve the utility of

the paper to readers:

1. The paper is well written. The authors do a very nice job of setting

   up a detailed economic model and then systematically adjusting

   the parameter values to assess sensitivity of the project to these

   adjustments.

2. Other than mentioning that snow fences are "useless" during the 

   summer months, and that PV fences will increase their overall 

   utility, the word "sustainability" does not appear in the text!

   It would be nice to learn why Switzerland developed these fences

   and the US chose not to follow. 

3. The reviewer would like to see a little more on the performance of

   these systems -- is there a cost-performance tradeoff that makes

   sense. This did not come across in my review of the paper.

Author Response

Reviewer 2:

There are a number of small items that could improve the utility of the paper to readers:

1. The paper is well written. The authors do a very nice job of setting up a detailed economic model and then systematically adjusting the parameter values to assess sensitivity of the project to these adjustments.

Thank you for the comment!

2. Other than mentioning that snow fences are "useless" during the summer months, and that PV fences will increase their overall utility, the word "sustainability" does not appear in the text! 

That is a good point! We revised the paper by adding the word “sustainability” in “Introduction” and “Conclusions”.

It would be nice to learn why Switzerland developed these fences and the US chose not to follow.

Switzerland developed the first PV noise barriers not PV snow fences. But apparently the US lags behind the European countries in using PV panels along highways. As indicated in the paper, “The development of PVSF provides the US an opportunity of a “corner overtaking” in developing highway PV projects.”, and this PVSF project/study would be the first one in the US and the world (to the best of our knowledge) to integrate PV panels with structural snow fences.

3. The reviewer would like to see a little more on the performance of these systems -- is there a cost-performance tradeoff that makes sense. This did not come across in my review of the paper.

Since the intention of the paper is to investigate the critical (most sensitive) parameters through the parameter analysis study of the cost-benefit model developed, so the cost performance is not the focus of the paper. But more cost-benefit results can be found from our MnDOT project report [42], which was added to the reference and mentioned in Conclusion.