Influencing Factors and Their Influencing Mechanisms on Integrated Power and Gas System Coupling
Round 1
Reviewer 1 Report (Previous Reviewer 1)
--some typos
--Please use in-text references correctly
--Methodology part should be more clearly described.
Minor editing of English language required
Author Response
Dear reviewer,
With this letter, I would like to thank you very much for taking the time to review my work and express my sincere gratitude to you for your suggestions on my revisions.
1. The text was checked and typos such as "influencing" and "awareness" were corrected.
2. In-text references have been placed in the correct position.
3. Chapter 4 describes the methodology section in a streamlined and efficient manner.
Reviewer 2 Report (Previous Reviewer 2)
Dear Authors,
The presented study is resubmitted after corrections and additions.
As I declared, the study addresses the current issue of integrating green power sources with gas-based sources. The "green power-to-hydrogen" approach is widely discussed because of periodical surpluses of green power, which can not be effectively used in the moment of generation.
Most comments about the previous version have been considered, and appropriate changes and additions have been made to the text.
Still, I'm not sure if the knowledge of experts in the "energy internet development model" or "energy network development" was used (line 238).
I also believe it is worth reaching for the literature on green power-to-gas systems. For example, you can discuss or refer to approaches in Sweden or Germany, where the aim is to use temporary excess electricity from wind farms or PV farms to produce hydrogen.
Author Response
Dear reviewer,
With this letter, I would like to thank you very much for taking the time to review my work and express my sincere gratitude to you for your suggestions on my revisions.
1. This study invites a professor from a university in Chengdu who is engaged in the design of an energy Internet development model to propose influential factors such as economic foundation, resource endowment, energy structure, etc., and evaluate the degree of influence between the factors in the IPGS coupling influencing factors index system.
2. This study cites the academic views of a German scholar named Sterner, in which he discusses the production of hydrogen using temporary excess electricity from wind farms or photovoltaic farms, and names the method of converting electricity into liquids, converting electricity into chemicals, and so on, as "Power-to-X".
Reviewer 3 Report (Previous Reviewer 4)
Since answer to all the queries are not satisfactory, the paper may be rejected
Author Response
Dear reviewer，
With this letter, I would like to express my sincere gratitude to you for your suggestions on my revisions. Thank you very much for taking the time to review my work and providing your valuable insights and comments.
Your professional insights and suggestions were very important to me. Based on your suggestions, I have made some modifications to my study and I am confident that these modifications will have a positive impact on the final results. Through your guidance, I was able to see details and potential points of improvement that I had not previously considered. The modifications are as follows.
1. There are some disadvantages of P2G technology that need to be considered and the following are some of the possible disadvantages:
(1) Energy conversion losses: During the electricity-to-gas conversion process, energy undergoes multiple conversions, for example, from electricity to hydrogen and from hydrogen to synthetic natural gas. These conversions may result in energy losses, which may reduce the energy efficiency of the system.
(2) Natural gas handling and storage: Natural gas in its high pressure or liquid form requires special storage and handling facilities, which may cause the system to remain somewhat dependent on fossil fuel infrastructure and involve safety and technical challenges.
(3) Environmental impacts: Although SNG is relatively cleaner, its production may still involve some carbon emissions, especially if the production process relies on fossil fuels.
(4) Costs: P2G technologies have high equipment and infrastructure development costs, especially in the initial stages. This may affect the economic viability of the technology, especially when compared to other energy storage technologies.
In response to these drawbacks, research and development is still ongoing to find more efficient, economical and environmentally friendly solutions for P2G, as cited in the revised article.
2. The interaction of the IPGS is characterized by some of the following:
(1) Interdependence: IPGS is interdependent in terms of supply and consumption. The power system may require gas to support generating facilities, while the gas system may require power to maintain the compression and delivery process.
(2) Balance of Supply and Demand: The production and consumption of power and gas need to be balanced to ensure stable system operation. Volatility and seasonal variations in the power system may affect gas demand, and gas prices and availability may affect the choice of how power is generated.
(3) Market Prices: power and gas systems have cross influences in energy markets. Changes in the price of gas may affect the cost of power generation and market competitiveness, while fluctuations in power market prices may also affect the demand for gas.
(4) Energy Policies: Government energy policies and regulations may also affect the interplay of IPGS. Policies that encourage renewable energy may affect power demand and generation patterns, which in turn may affect gas demand.
Overall, the interaction of IPGS is a complex issue that requires a combination of market, technology, policy, and other factors, and the revised article cites relevant studies.
3. (1) Energy Conversion Efficiency of Gas-fired Power Generation: Gas-fired power generation is the process of generating electricity by burning a fuel such as natural gas. The efficiency of this type of power generation can be measured through thermal and electrical efficiency.
(2) Energy conversion efficiency of P2G: P2G involves processes such as electrolyzing water to produce hydrogen and synthesizing natural gas. These conversion processes involve energy losses, such as the efficiency of electrical energy conversion in the case of electrolysis of water and the efficiency of chemical conversion in the case of synthesis of natural gas.
Currently, the energy conversion efficiency is 33.21% for Gas-fired power generation, 56.98% for combined cycle power plants and 62.47% for P2G. The revised article cites relevant studies.
4. P2G can offer a number of viable options in transitioning to a sustainable, low-carbon future energy system:
(1) Renewable energy smoothing: P2G can help address the volatility of renewable energy. By converting excess solar or wind energy into stored fuels such as hydrogen, they can bridge the energy gap and maintain the stability of the energy system in the event of a shortfall in energy supply.
(2) Energy Storage and Transportation: P2G converts energy into gases that can be more easily stored and transported. This is useful during times of peak demand or when energy is transmitted over long distances, helping to achieve a balanced distribution of sustainable energy.
(3) Reduced Carbon Emissions: P2G utilizes renewable energy sources to generate electricity, avoiding the carbon emissions associated with traditional methods of power generation, such as coal combustion. The use of hydrogen or other gaseous fuels for energy conversion also does not directly generate carbon emissions, helping to reduce the overall carbon footprint.
(4) Industrial Transformation: Promoting the development and application of P2G can help facilitate industrial transformation from traditional high carbon energy sources to low carbon energy sources. This will help meet international carbon reduction commitments and accelerate sustainable development.
The revised article cites relevant studies.
5. We have further refined this section to consider that market prices have a direct impact on the production costs, supply/demand balance, investment decisions and sustainability of IPGS.
(1) Production Cost Impacts: If market prices increase, the cost of energy, raw materials, and equipment used in the IPGS may increase. For example, an increase in the price of natural gas will directly increase the cost of the natural gas portion of the IPGS, affecting the overall cost of operating the system.
(2) Supply and Demand Balance Impact: Consumers may demand less energy when market prices increase, as high prices may prompt them to look for more economical energy options. This may lead to an imbalance between supply and demand, and if supply is not sufficient to meet demand at high prices, a supply shortage may occur.
(3) Investment Decision Implications: High market prices may encourage more investors to enter the IPGS sector, as they may see profit opportunities therein. However, high market prices may also lead to over-investment, which may have a negative impact on the profitability of IPGS in the long term.
(4) Sustainability Implications: If the market price is higher than the cost of production of renewable energy, it may slow down the adoption of renewable energy. However, government policies and incentives can also promote sustainable development by influencing market prices.
Due to the length, the article does not explain the logic of the four aspects of market prices affecting IPGS in the text, but from the above, it is clear that market prices are one of the important factors affecting the coupling of IPGS.
6. The revised article has improved that part of the article. Awareness of IPGS in society can be raised in five ways:
(1) The knowledge of IPGS should be popularized to the society through vari-ous channels such as media propaganda and school education, and the awareness and participation of the society in environmental protection should be improved through various means such as encouraging green technology innovation and improving envi-ronmental protection laws and regulations.
(2) Community outreach activities should be strengthened, and IPGS exhibitions or demonstration projects should be or-ganized to show how it works, its practical applications and environmental impacts, so as to give people a close-up understanding of IPGS and provide them with hands-on experience.
(3) Partnerships should be promoted among government agencies, non-profit organizations, energy companies, and other relevant entities to enhance re-source sharing, disseminate IPGS information more effectively, and work together to promote community-wide awareness of IPGS.
(4) It should focus on environ-mental protection in the construction and operation of IPGS, and strengthen the edu-cation and management of environmental protection consciousness of IPGS-related personnel in order to achieve sustainable development and maximize social benefits.
(5) A scientific environmental protection management and pollution evaluation system should be established to strengthen the environmental protection supervision and management of IPGS and conduct a comprehensive environmental impact evalu-ation to ensure the compliance and safety of the system.
7. Previously, the concepts of influence and influenced degree were not introduced in Chapter 4 which may have caused obstacles for readers, so the revised article provides further explanations. In the DEMATEL method, Influence Degree ei and Influenced Degree fi are concepts used to measure the strength of the relationship between factors influencing each other.
(1) Influence Degree: Influence Degree is the degree or strength of influence of a factor on other factors. In DEMATEL analysis, the Influence Degree value indicates the direct influence of a factor on all other factors. A higher influence degree value indicates that the factor has a greater influence on the other factors. Affected Degree can be used to quantitatively assess the interrelationships between factors and help determine which factors have a higher weight or importance in a problem.
(2) Influenced Degree: Influenced degree is the degree to which a factor is influenced by other factors. In a DEMATEL analysis, the Affected Degree value indicates the direct influence of other factors on the factor. The higher the value of Influenced Degree, the more the factor is influenced by other factors. The degree of influence helps to understand which factors are in a more passive position in the problem and are more likely to be influenced by other factors.
By calculating the degree of influence and the degree of being influenced, it is possible to construct a map of the influence relationships between factors, which helps to analyze the cause and effect relationships in a problem, identify key factors, and provide insight into the interactions between factors. This helps to more accurately analyze problems, make decisions, and develop appropriate strategies.
8. One of the main objectives of the IPGS coupling is to accelerate the market construction, which involves the exploration and development of electricity and natural gas resources.
(1) Integrate energy resources: Integrate electricity and natural gas resources to form an integrated energy system. This can promote more efficient utilization of resources, reduce energy waste, and thus increase the efficiency of exploration and development.
(2) Partnerships and Joint Ventures: Companies in the power and natural gas sectors can engage in partnerships and joint ventures to develop energy resources together. Collaboration can combine the technology, experience and resources of both parties, reducing development costs and accelerating the E&P process.
(3) Technological Innovation: Invest in research and development of new exploration, extraction and production technologies to improve the efficiency and sustainability of energy resource development. Innovative technologies can improve the exploration process and increase production efficiency while reducing environmental impacts.
Overall, the exploration and development of electricity and natural gas resources includes a multifaceted effort to consolidate resources, technological innovation, and more. The revised article has been added in section 6.2 accordingly.
9. Determining the level of influence between factors is a key step in the DEMATEL methodology, which involves expert opinion and data collection. The following are the general steps in determining the direct influence matrix:
(1) Problem Definition and Factor Identification: Start by clearly defining the problem and identifying the factors associated with the problem.
(2) Expert Opinion Collection: Involve experts in the relevant fields and ask them to assess the level of influence between each factor based on their experience and knowledge.
(3) Constructing the Direct Impact Matrix: Summarize the assessment of the degree of influence provided by the experts and construct the Direct Impact Matrix according to the method of taking the average value.
Through these steps, the direct influence matrix reveals the influence relationship between the factors, helps to analyze the causality of the problem, and provides the basis for the subsequent DEMATEL analysis.
In this study, 10 experts and scholars engaged in related research fields were invited to assess the degree of direct influence between the influencing factors of the coupled electric power-gas system according to the gray semantic scale (Table 2), so as to determine the degree of influence between the influencing factors of the IPGS coupling, and to obtain the direct influence matrix by taking the average.
10. The Cross-Impact Matrix Multiplication Method (MACMIC) categorizes the influences into four categories which allows for a clearer understanding of the interactions between the factors and an understanding of the substantial role of each factor in the system.
11. Answered in point 9.
12. The revised article gives some examples of DEMATEL-ISM-MACMIC specific implementations in Methodology to enrich the chapter and this paper describes the research steps of DEMATEL-ISM-MACMIC method. This study describes the specific research steps of the DEMATEL-ISM-MACMIC method in Chapter 4 and presents the key data of this study (Direct Impact Matrix O) in Chapter 5 of the text (Table 3), based on which replicable conclusions consistent with this paper can be drawn.
13. The limitation of the application of the DEMATEL-ISM-MACMIC method is the subjectivity and variability of the expert evaluation factors. Therefore, this study ensures the validity and scientificity of the research results by selecting experts with high authority and representativeness, using SPSS to test the reliability of the opinions of expert scholars, and adopting the method of averaging the expert data to weaken and eliminate as much as possible the differences in ratings due to differences in specialties, preferences, and personal knowledge.
Thank you again for your help and guidance. I greatly appreciate your input into my work.
Author Response File: 
Author Response.pdf
Round 2
Reviewer 3 Report (Previous Reviewer 4)
Since the answer to all the queries are satisfactory, the paper may be accepted
This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
Round 1
Reviewer 1 Report
This manuscript focuses on studying the Influencing factors and their influencing mechanisms on Inte-2 grated Power and Gas System coupling. Personally thinking, the topic is interesting and worthy studying, but the manuscript cannot reach the minimal requirements of the journal concerning the following comments
1. Avoid excessive use of uncommon abbreviations that can make the article difficult to read. If abbreviations are unavoidable, please use the full form in each chapter on its first occurrence.
2. The references are a bit old, and I believe there are many relevant studies in the last three years.
3. Too much background introduction and literature review. The content before chapter 4.4 is all background and literature review, which takes up four full pages.
4. Innovation is not clear, and I didnt find the innovations. I believe that chapter 4.4 is to introduce your methodology and innovations, but you juts introduce the analysis steps of DEMATEL-ISM-MICMAC. as you mentioned that 'the DEMATEL-ISM-MICMAC method has been applied in several fields such as manufacturing [27], agriculture [28] and energy [29] and its advantages have been well demonstrated'. Thus, DEMATEL-ISM-MICMAC method has been widely used, and it is not your innovation.
5. Abstract part is not well structured. The meaning of the first two sentences is repetitive. And the abstract should clearly explain the innovation points and new methods used, and then give corresponding conclusions, preferably quantitative conclusions. I didn't find the key content in your summary, and the abstract is a bit confusing.
6. The results of this article are somewhat confusing, and some methods are described in the results section.
7. Insufficient results, mixed with many method introductions.
8. some typos or minor mistakes
moderate improvement
Reviewer 2 Report
Dear Authors,
The study addresses the current issue of integrating green energy sources with gas-based sources. The "green power-to-X" approach is currently widely discussed and researched due to the volatility of renewable energy production.
The methodological approach used (DEMATEL-ISM-MACMIC_) is suitable for considering factors important to such still not fully understood issues. An important aspect is that, based on a few key factors, and based on the judgment of a few experts, the importance and hierarchy of factors can be established. I have a few comments from reading the text.1. The purpose of the study should be better addressed and more clearly described (lines 55-62).
. The word "Internet" is used instead of "network" when discussing the development of the power grid. Is it intentional?
3. As part of the P2G technology, it is indicated that natural gas is produced (a mixture of natural gaseous hydrocarbons). In fact, hydrogen is produced, which can be methanized etc. This requires a proper description. (mainly lines 73-81).
4. Some abbreviations are not explained, e.g. IES (?integrated energy system?) line: 96.
5. Section 3 states that there are some "relevant factors". It should be that these are factors considered important by the authors/experts (lines 136-170). isn't it?
6. For clarity and better understanding of the methodology, what is "I" (identity matrix), "k" (?number of experts?) should be explained. An interesting example of a method description is in https://doi.org/10.1007/s10668-023-03364-0
7. Should the description in lines 221-222 not contain a distinction between the directions of action.
8. Specify how λ (threshold) was calculated or indicate that it is determined arbitrarily - and what levels of λ were adopted.
9. Figure 2 needs better description, like axes etc.
10. The results are quite well described. I would suggest adding a limiting section where it could be indicated that the results are not fully universal; are based on the opinions of 10 experts from a specific region of the world. They also reflect the beliefs of these experts. I also believe that it can be pointed out that some of the indicators are based on the assessment of experts. In the future, verifying their legitimacy in further research will be possible and necessary.
11. References to sources not in the text are always given correctly, as in APA style. Instead of He (2018) it should be He [8]? This is the case with direct citation.
n/d
Reviewer 3 Report
I don't advise this paper to be published in the Sustainability Journal.
I don't advise this paper to be published in the Sustainability Journal.
Reviewer 4 Report
In this paper by means of literature review and field research, on the basis of summarizing and forming the index system of IPGS coupling influence factors, this study establishes the IPGS coupling influence factor model based on DEMATEL-ISM MACMIC method, analyze the attribute characteristics of each factor influencing IPGS coupling and extract the key elements, explore the logical relationship among the factors. The paper is well written, but the following queries have to be answered.
1. You have mentioned that “Power-to-gas (P2G) can convert power system energy into natural gas, indirectly achieving large-scale and long-term storage of electrical energy”. What are the disadvantages of P2G Conversion.
2. What are the characteristics of interactive influences of Integrated Power and Gas System (IPGS)?
3. What is the efficiency of Gas-fired power generation and P2G mutual conversion of electricity and natural gas?
4. How P2G offers viable options for transitioning towards a sustainable low-carbon future energy system
5. How Market price directly affects production costs and the supply and demand balance for IPGS.
6. How do you increase awareness of IPGS in society?
7. What is influence degree ?? , influenced degree ?? in DEMATEL-ISM-MICMAC method?
8. How “Accelerating market construction”, the primary content of IPGS coupling, strengthens the exploration and development of electricity and natural gas resources?
9. How degree of influence among the influencing factors of IPGS coupling was determined,
10. You have taken only four factors as quadrants, spontaneous factor, dependent factor, linked factor and independent factor. Did you compromise on other factors?
11. How do you arrive at Direct impact matrix?
12. The DEMATEL-ISM-MACMIC method that combines the three can achieve complementary advantages, both in clarifying the importance and causal nature of each factor of the system, and in deepening the understanding of the logical relationships and hierarchical structure among the factors. The implementation details are inadequate. Also give some specific examples of implementation.
13. You have asked 10 experts and scholars to evaluate the degree of interaction among the influencing factors of power-gas system coupling. So DEMATEL-ISM-MICMAC method is primarily based on the quality of experts than its logics of the method? Comment
This paper may not be accepted in its present form and may be accepted after the satisfactory responses to the above queries.
