Techno-Economic Analysis of an All-Electric Energy Station in Eastern China

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The paper presents a timely and detailed techno-economic assessment of an all-electric energy station in Eastern China, a concept closely aligned with the carbon neutrality targets and energy transformation goals. The integration of economic, technical, and environmental evaluations provides a holistic perspective, making the study relevant to both policymakers and infrastructure developers. 

One particularly promising yet underexplored avenue is the connection between the all-electric station and the growing demand for electric vehicle (EV) charging infrastructure. The study briefly notes the inclusion of smart systems and storage technologies, which are foundational for EV charging applications. Integrating EV charging into the station’s operational model would not only improve asset utilization and diversify revenue streams but also support urban decarbonization and transportation electrification. Addressing this potential synergy, perhaps through joint load modeling or siting strategies, would elevate the strategic relevance of the paper and open new directions for research in integrated energy-transport systems. In this context, existing research on EV charging location optimization can offer valuable methodologies for extending the current analysis. All in all, to this end, I’d recommend checking “C. Loaiza-Quintana et al. Iterated local search for the ebuses charging location problem. PPSN 2022. DOI: 10.1007/978-3-031-14721-0_24,” which provides a robust computational framework for siting electric bus charging stations that could be adapted for integrated energy systems.

However, the paper would benefit from a clearer description of its system boundaries and assumptions. While the energy station is presented as operational and data-rich, there is limited detail on the exact site characteristics, user base, or deployment scale, making the analysis harder to generalize or replicate. Additionally, although seasonal system performance and coefficient of performance  values are discussed, there is little engagement with dynamic operating conditions such as part-load performance, weather variability, or potential degradation over time. A more nuanced treatment of system performance under real-world variability would improve the robustness of the findings.

From an economic standpoint, the analysis effectively applies standard metrics such as Net Present Value (NPV), Internal Rate of Return (IRR), and payback period. These results provide a clear comparison with conventional electricity-gas systems. However, the model lacks lifecycle costing elements like capital depreciation and asset replacement cycles. Furthermore, the use of a fixed carbon tax rate ignores future policy volatility, which is particularly important in China’s evolving emissions pricing landscape. While the paper includes a sensitivity analysis, it remains largely qualitative, and would benefit from quantifying how shifts in variables (e.g., discount rate, cooling price) affect outcomes.

On the environmental side, the study makes a strong case for carbon emission reductions, estimating an 11.5% decrease relative to traditional systems. This claim is persuasive, but the underlying calculation method is unclear. The analysis does not appear to account for lifecycle emissions from infrastructure or equipment, nor does it incorporate evolving grid emission factors over the system's operational lifetime. A more comprehensive life cycle assessment (LCA), even at a high level, would add significant weight to the environmental claims and better align the study with international sustainability assessment standards.

The paper is a bit verbose and repetitive, especially in the introduction and background sections. Reducing redundancy and clarifying some concepts would help readers focus on the core contributions. 

Author Response

Comments1:One particularly promising yet underexplored avenue is the connection between the all-electric station and the growing demand for electric vehicle (EV) charging infrastructure. The study briefly notes the inclusion of smart systems and storage technologies, which are foundational for EV charging applications. Integrating EV charging into the station’s operational model would not only improve asset utilization and diversify revenue streams but also support urban decarbonization and transportation electrification. Addressing this potential synergy, perhaps through joint load modeling or siting strategies, would elevate the strategic relevance of the paper and open new directions for research in integrated energy-transport systems. In this context, existing research on EV charging location optimization can offer valuable methodologies for extending the current analysis. All in all, to this end, I’d recommend checking “C. Loaiza-Quintana et al. Iterated local search for the ebuses charging location problem. PPSN 2022. DOI: 10.1007/978-3-031-14721-0_24,” which provides a robust computational framework for siting electric bus charging stations that could be adapted for integrated energy systems.

Response1: Thank you for the recommended reference. We have added it to the revised manuscript along with the relevant introduction.

Comments2:However, the paper would benefit from a clearer description of its system boundaries and assumptions. While the energy station is presented as operational and data-rich, there is limited detail on the exact site characteristics, user base, or deployment scale, making the analysis harder to generalize or replicate. Additionally, although seasonal system performance and coefficient of performance  values are discussed, there is little engagement with dynamic operating conditions such as part-load performance, weather variability, or potential degradation over time. A more nuanced treatment of system performance under real-world variability would improve the robustness of the findings.

Response2: Thank you for your comment. System boundaries and assumptions have been added to the revised manuscript. Additionally, site characteristics, user base, and deployment scale have been included. We have also considered part-load performance (off-peak time); however, due to data limitations from the real plant, we were unable to account for weather variability and potential degradation over time.

Comments3:From an economic standpoint, the analysis effectively applies standard metrics such as Net Present Value (NPV), Internal Rate of Return (IRR), and payback period. These results provide a clear comparison with conventional electricity-gas systems. However, the model lacks lifecycle costing elements like capital depreciation and asset replacement cycles. Furthermore, the use of a fixed carbon tax rate ignores future policy volatility, which is particularly important in China’s evolving emissions pricing landscape. While the paper includes a sensitivity analysis, it remains largely qualitative, and would benefit from quantifying how shifts in variables (e.g., discount rate, cooling price) affect outcomes.

Response3: In this work, the TEA model was developed based on a real power station located in Shanghai. The power station has a design lifetime of 30 years, so the economic analysis—including NPV, IRR, and payback period—was conducted over this 30-year period. Equipment maintenance costs were also included in the calculations. In the sensitivity analysis, different precise values for the carbon tax rate and discount rate and cooling price were used to quantitatively assess how variations in these rates affect the economic performance.

Comments4:On the environmental side, the study makes a strong case for carbon emission reductions, estimating an 11.5% decrease relative to traditional systems. This claim is persuasive, but the underlying calculation method is unclear. The analysis does not appear to account for lifecycle emissions from infrastructure or equipment, nor does it incorporate evolving grid emission factors over the system's operational lifetime. A more comprehensive life cycle assessment (LCA), even at a high level, would add significant weight to the environmental claims and better align the study with international sustainability assessment standards.

Response4: Thank you for your comments. A clear calculation method for carbon emission reduction has been added to the revised manuscript, which takes into account the grid emission factor over the system’s operational lifetime. In the current work, the system boundary encompasses the entire process from energy input to final energy output. Specifically, the system begins with upstream power and gas supply, using external electricity and gas as driving energy sources. Therefore, we consider only the carbon emissions associated with electricity and gas consumption.

Comments5:The paper is a bit verbose and repetitive, especially in the introduction and background sections. Reducing redundancy and clarifying some concepts would help readers focus on the core contributions.

Response5:Thanks for comments. Verbose and repetitive issue have been addressed in revised manuscript. 

Reviewer 2 Report

Comments and Suggestions for Authors

Firstly, the paper should be prepared in accordance with editorial requirements.

Secondly, the purpose and hypothesis should be clearly indicated.

Thirdly, the methodology should be clear. The description of the complexity of the analyzed system should be described in a different part of the study and not in the methodology. I propose to introduce the subject of the study part and present the complexity of the analyzed system in this place. In the research method, I propose to include the method and the procedure in the study (its subsequent stages). Also in the proposed part, some of the information given in the introduction can be included.

Fourthly, in the conclusions, it is worth indicating the effects of using solutions at the macro level.

Fifthly, reference should be made to research conducted around the world in this area.

Author Response

Comments1:Firstly, the paper should be prepared in accordance with editorial requirements.

Response1: Thanks for the comment. The manuscript has been revised in accordance with the editorial requirments.

Comments2:Secondly, the purpose and hypothesis should be clearly indicated.

Response2: Thanks for your comment. The purpose and hypotheses have been clarified in the revised manuscript.

Comments3:Thirdly, the methodology should be clear. The description of the complexity of the analyzed system should be described in a different part of the study and not in the methodology. I propose to introduce the subject of the study part and present the complexity of the analyzed system in this place. In the research method, I propose to include the method and the procedure in the study (its subsequent stages). Also in the proposed part, some of the information given in the introduction can be included.

Response3:Thanks for the comments. The manuscript has been revised accordingly.

Comments4:Fourthly, in the conclusions, it is worth indicating the effects of using solutions at the macro level.

Response4: Thanks for the comments. The manuscript has been revised accordingly.

Comments5:Fifthly, reference should be made to research conducted around the world in this area.

Response5: Thanks for comments. More reference was added in revised manuscript.

Reviewer 3 Report

Comments and Suggestions for Authors

The paper presents an analysis of a fully electric energy station, comparing it against integrated electric-gas system. The work focused not only on the technical aspect, but economical and environmental impacts as well. Results revealed that an all-electric energy station brings financial savings while also reducing emissions.  
The paper is interesting, showing an analysis based on a real plant. The subject matter is also of importance, as decarbonization of heating and cooling systems is a global challenge. References are adequate and up-to-date. There are, however, some issues that could be addressed to improve the paper:
1. In the title of the paper, but inside the text as well the phrase "energy station" is used. However, the description of this energy stations appears in fig. 1/p. 8. While not a critical issue, the Authors could consider adding some description earlier, defining what type of object this energy station is. 
2. In tables 1 and 2, there are parameters described as "cooling capacity", "power consumption" and "cooling load", with the unit of kW. Are those all figures of power or energy? Clarification is recommended.
3. The equations formatting is inconsistent, sometimes using the same font as the paper body and sometimes the equation editor. This should be improved as it impacts readability of the equations.

Author Response

Comments1:1. In the title of the paper, but inside the text as well the phrase "energy station" is used. However, the description of this energy stations appears in fig. 1/p. 8. While not a critical issue, the Authors could consider adding some description earlier, defining what type of object this energy station is. 

Response1:Thank you for your comment. A description has been added in the revised manuscript.

Comments2:In tables 1 and 2, there are parameters described as "cooling capacity", "power consumption" and "cooling load", with the unit of kW. Are those all figures of power or energy? Clarification is recommended.

Response2: Thank you for comments. The clarification is added in revised manuscript.

Comments3:The equations formatting is inconsistent, sometimes using the same font as the paper body and sometimes the equation editor. This should be improved as it impacts readability of the equations.

Response3:Thank you for comments. All of equations was revised in revised manuscript.

Reviewer 4 Report

Comments and Suggestions for Authors

The authors address a interest topic, but the following clarifications are needed:

-  It is necessary to correct Figure 1: Electricity Eupply and Tater storage tank.

- Also in Figure 1, the gas supply of the gas boiler is missing.

- At the R 233, the flow and return temperatures must be specified because otherwise the expression "supply/return water temperatures" from R 232 implies that, for heating, the flow temperature is 42 and the return temperature is 49.

- It should be explained how the tank volume of 20,000 m³ was established. What are the calculation assumptions?

- Placing cooling towers and heat pumps on the roofs of buildings implies an additional load that must be taken into account when designing the building structure. This aspect is not discussed.

- What is the temperature cooling water.

- The last line in table 2 refers to Heating capacity (kW)? A clarification is needed.

- For the terms that enter into the calculation relationships, the units of measurement must be specified.

- Calculation relations 4,5,7,8 must be corrected (writing method).

Author Response

Comments1: It is necessary to correct Figure 1: Electricity Eupply and Tater storage tank.

Response1:Figure1 was updated in revised manuscript.

Comments2:Also in Figure 1, the gas supply of the gas boiler is missing.

Response2:Figure1 was updated in revised manuscript which include the gas boiler.

Comments3:At the R 233, the flow and return temperatures must be specified because otherwise the expression "supply/return water temperatures" from R 232 implies that, for heating, the flow temperature is 42 and the return temperature is 49.

Response3: the flow and return temperatures was specified in revised manuscript.

Comments4:It should be explained how the tank volume of 20,000 m³ was established. What are the calculation assumptions?

Response4: This value is given by the real plant. We also emphasized this point in the revised manuscript.

Comments5:Placing cooling towers and heat pumps on the roofs of buildings implies an additional load that must be taken into account when designing the building structure. This aspect is not discussed.

Response5: This design is realized in real station, and we have also clarified this point in the revised manuscript.

Comments6:What is the temperature cooling water.

Response6:In cooling mode, the air conditioning supply water temperature is maintained at 5°C and the teturn water temperature at 12°C. We have also added an explanation in the revised manuscript.

Comments7:The last line in table 2 refers to Heating capacity (kW)? A clarification is needed.

Response7: A clarification have been added in the revised manuscrpt.

Comments8: For the terms that enter into the calculation relationships, the units of measurement must be specified.

Response8: the units of meansurement was added in revised manuscript.

Comments9:Calculation relations 4,5,7,8 must be corrected (writing method).

Response9:Calculation relations was corrected in revised manuscript.

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The authors have updated the paper to improve its clarity, depth, and relevance. First, a new section was added to explore the potential integration of electric vehicle (EV) charging infrastructure into the all electric energy station. This section discusses how smart energy management and thermal storage can support coordinated EV charging, and includes relevant references.

The revised document now provides specific details about the service area, load types, seasonal demand profiles, and assumed equipment degradation rates. To strengthen the economic analysis, lifecycle cost elements such as capital depreciation, equipment replacement, and start up costs have been incorporated, along with a sensitivity range for carbon tax rates to reflect potential future policy changes.

The authors now explain how emissions reductions were calculated and acknowledge the exclusion of embodied emissions. A discussion of possible future improvements, including basic life cycle assessment (LCA) and dynamic grid emission factors, has been added to better align with international sustainability standards. Collectively, these changes enhance the paper’s technical rigor and strategic value.

Some citations lack sufficient bibliographic detail (e.g., missing volume, issue, or DOI), and several appear as vague placeholders. To ensure clarity and proper attribution, the reference list should include the full names of all authors when a source has fewer than six authors, in accordance with widely accepted citation standards. For example, please review references [6], [8], [11], and [13], among others.

Finally, many sentences throughout the manuscript are overly long and complex. A thorough proofreading is recommended to improve readability.

Comments on the Quality of English Language

Many sentences throughout the manuscript are overly long and complex. A thorough proofreading is recommended to improve readability.

Author Response

Comments1:Some citations lack sufficient bibliographic detail (e.g., missing volume, issue, or DOI), and several appear as vague placeholders. To ensure clarity and proper attribution, the reference list should include the full names of all authors when a source has fewer than six authors, in accordance with widely accepted citation standards. For example, please review references [6], [8], [11], and [13], among others.

Response1:We have updated references in the revised manuscript.

Comments2:Finally, many sentences throughout the manuscript are overly long and complex. A thorough proofreading is recommended to improve readability.

Response2:We have done proofreading to improve readability.