Estimating Thermal Impact on Groundwater Systems from Heat Pump Technologies: A Simplified Method for High Flow Rates

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The paper presents a comprehensive study addressing the thermal impact on groundwater systems arising from the implementation of thermal technologies through extraction and injection wells. The authors have developed a novel method, integrating analytical calculations and numerical modeling, to assess thermal impacts for flow rates exceeding 2 l/s. Overall, the paper is well-written, and the results are effectively presented. However, I recommend some minor revisions to enhance the clarity and robustness of the study.

 

Minor comment

- ln. 42: Refence 42 is a bit old, there were several recent studies dealing with the effect of heterogeneity of subsurface properties on the efficiency of geothermal systems that should be considered, such as:

Liu, G., Pu, H., Zhao, Z., & Liu, Y. (2019). Coupled thermo-hydro-mechanical modeling on well pairs in heterogeneous porous geothermal reservoirs. Energy, 171, 631-653.

Di Dato, M., D’Angelo, C., Casasso, A., & Zarlenga, A. (2022). The impact of porous medium heterogeneity on the thermal feedback of open-loop shallow geothermal systems. Journal of Hydrology, 604, 127205.

- Eq. (2): this is the darcian velocity. The real seepage velocity should be divided by porosity.

- Ln 112: this conditions was mathematically proven by Luo, J., & Kitanidis, P. K. (2004). Fluid residence times within a recirculation zone created by an extraction–injection well pair. Journal of Hydrology, 295(1-4), 149-162.

- It seems that eq. (6) and (7) are the same equation, in this case they should have a unique numbering

- Ln. 174: in the form of what?

- Tables 2 and 3: Can you give some reference on the value used?

 

In conclusion, the paper offers valuable insights into estimating thermal impacts on groundwater systems. The suggested minor revisions aim to enhance the clarity and completeness of the study, ensuring that readers can fully grasp the methodology and results presented. Overall, the paper demonstrates a commendable effort and contribution to the field. I recommend acceptance with minor revisions.

Author Response

Thank you very much for taking the time to review this manuscript. Please find the detailed responses below and the corresponding revisions/corrections highlighted in the re-submitted file.

Corrections:

• ln. 42: Refence 42 is a bit old, there were several recent studies dealing with the effect of heterogeneity of subsurface properties on the efficiency of geothermal systems that should be considered, such as:
• Liu, G., Pu, H., Zhao, Z., & Liu, Y. (2019). Coupled thermo-hydro-mechanical modeling on well pairs in heterogeneous porous geothermal reservoirs. Energy, 171, 631-653.
• Di Dato, M., D’Angelo, C., Casasso, A., & Zarlenga, A. (2022). The impact of porous medium heterogeneity on the thermal feedback of open-loop shallow geothermal systems. Journal of Hydrology, 604, 127205.

I have added this references as [13,14]

• - Eq. (2): this is the darcian velocity. The real seepage velocity should be divided by porosity.

I have corrected it: "vx  expresses the Darcy velocity "

• - Ln 112: this conditions was mathematically proven by Luo, J., & Kitanidis, P. K. (2004). Fluid residence times within a recirculation zone created by an extraction–injection well pair. Journal of Hydrology, 295(1-4), 149-162.

I have added this references as [17]

• - It seems that eq. (6) and (7) are the same equation, in this case they should have a unique numbering

I have changed numbering, both equaitions have no.6

• - Ln. 174: in the form of what?

There was an error in the sentence, I have corrected it: "we have chosen the parameter  in the form:"

• - Tables 2 and 3: Can you give some reference on the value used?

Values in the tables represent typical values in Slovakia, I add this fact into article: "The values in Tables 2 and 3 are typical values for alluvial sediments in Slovakia."

Reviewer 2 Report

Comments and Suggestions for Authors

I found your work interesting and applicable to the GWHP industry; however, the concepts are vaguely expressed in several places. Please use scientific language and make it understandable even to readers with little knowledge about GWHPs. While the work is generally well presented, the abstract is challenging to read and follow. Please spend some time and make it meaningful and lucid to read. I am sure you can do that easily with some effort. 

Comments on the Quality of English Language

The writing is not very interesting to read. Authors should try to ensure a flow and coherency in writing. Also, please use scientific language.

Author Response

Thank you very much for taking the time to review this manuscript. Please find the detailed responses below and the corresponding revisions/corrections highlighted in the re-submitted files.

I have reformulated the Abstract, please see the resubmitted article.

Thank you for your comments on the quality of the English language in the article. I apologize for any confusion caused. I have identified and corrected the formulations that required improvement. I have made the necessary revisions to enhance the clarity and readability of the article.

Thank you for your understanding and assistance in improving the quality of the manuscript.

Here are the corrections:

line 66:

Example of poor use of scientific language: "To apply the analytical formulas, certain restrictions had to be adhered to."

Proposed correct formulation: "In order to utilize the analytical formulas, specific conditions and limitations were considered."

line 86:

Example of poor use of scientific language: "The velocity field was expressed as a function of position and pumped water quantity."

Proposed correct formulation: "The velocity field was determined based on the position and the amount of water being pumped."

line 213

Example of poor use of scientific language: "The planar advective model of heat transport was deemed the most appropriate approximation."

Proposed correct formulation: "The planar advective model was selected as the most suitable approximation for heat transport."

line 268

Example of poor use of scientific language: "The numerical model was compiled on the basis of the assumptions of the analytical solution mentioned above."

Proposed correct formulation: "The numerical model was developed based on the assumptions described in the analytical solution mentioned earlier."