A Study on Carbon-Reduction Strategies for Rural Residential Buildings Based on Economic Benefits in the Gannan Tibetan Area, China

Round 1

Reviewer 1 Report (Previous Reviewer 1)

Comments and Suggestions for Authors

The updated manuscript successfully responds to most of the comments, particularly those pertaining to the socioeconomic background, research constraints, clarity of methodology, and the use of visual aids. The discussion has also improved in its depth and balance, particularly around obstacles to implementing carbon reduction strategies.

Author Response

Comment 1: The updated manuscript successfully responds to most of the comments, particularly those pertaining to the socioeconomic background, research constraints, clarity of methodology, and the use of visual aids. The discussion has also improved in its depth and balance, particularly around obstacles to implementing carbon reduction strategies.

Response 1: The authors express their gratitude for the editor’s comments.

Reviewer 2 Report (Previous Reviewer 2)

Comments and Suggestions for Authors

Abstract:

·       I would disagree with the statement regarding building envelope upgrades in Lines 24 and 25. The results does show some impact of building insulation upgrades. Please rephrase it.

Introduction:

·       Could the authors provide more insights on the emissions % provided in Lines 75 through 78? The values seem very high and does not seem reasonable. For instance, operational stage accounts for 99.5% of building life cycle and material production accounts to 98%? The numbers does not add up.

Research Methods:

·       I would encourage the authors to either mention any climate zone details of the selected village or maybe provide a table with monthly average temperatures. This would help the readers understand the climatic conditions in a better way.

·       Also, please mention the source from where these temperatures were recorded.

·       Were only two days selected for the thermal testing? It might not be sufficient to draw any conclusions. It would be great to study the influence of temperatures over energy usage for at least an entire season.

·       In Figure 5, it looks like the surface temperatures of the wall was recorded only on one side of the building. This might not be a useful set of information to work with since the solar radiation could differ based on the wall locations.

·       How many windows are there in the selected building? Figure 5 shows only two window temperatures being captured.

·       How were the U-Values determined in Table 1? If any standard values of the materials were used, then please add the details of that source and create a table to list out the U-values of all individual materials.

·       Please add the HVAC equipment details.

·       How were the equations used in Section 3.3 derived? Using any field data or was it adopted from any previous studies? Please add the sources of these equations.

·       Please check the error on Line 152.

·       How was the energy consumed by various equipment obtained? Were there any sensors installed? Please add more details about that.

Results and Discussions:

·       How was the solar radiation value mentioned in Section 4.1.2 obtained?

·       No proper supporting data/findings/literature for the statements in Lines 261 through 264.

·       How were the heat losses calculated in Table 3 determined?

·       Which table are the authors talking about in Lines 281 and 282?

·       I would suggest replacing the word investment in Table 6 with operating cost.

Conclusions:

·       Proper data analysis required to draw the current conclusions.

Comments on the Quality of English Language

Can be improved

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report (New Reviewer)

Comments and Suggestions for Authors

• In paper is " Energy efficiencies of 50%, 55%, 60%, 65%, and 70% with the different structures and heat transfer coefficients of the building envelopes were shown in Table 5."  In Table 5 no Energy efficiencies.
  
• How to understand energy efficiency (Table 6)?
• How to understand heating efficiency (Table 7)? What is heating efficiency for air heat pump at -20^oC? 
  Table 7 can be supplemented with column: price of 1 kWh of heat.
• What about heating efficiency optimization? What is the objective function/ What are the objective functions and what are the limiting assumptions?

Author Response

Please see the attachment.

 

Author Response File: Author Response.pdf

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

Comments and Suggestions for Authors

1. The introduction section needs to adequately provide the socioeconomic backdrop of the Gannan area. The report states that economic issues must be addressed when lowering carbon emissions but does not include information on Gannan's average income, employment types, or other socioeconomic aspects that may affect the viability of the recommended measures. For instance, if most locals work in low-income agriculture, they may need help to invest in new heating systems.

2. • The “literature review” does not critically assess study limitations, a crucial aspect in understanding the viability of the discussed experiments. The study discusses biomass and heat pump experiments but does not examine their drawbacks, such as high upfront costs or distant maintenance issues. Understanding these drawbacks is essential for a comprehensive evaluation of the strategies.

3. • The "Research Methodology" section lacks clarity in explaining the criteria for selecting the questioned houses. A clear and transparent methodology is crucial in understanding the applicability of the survey findings. For instance, the report references the implementation of a survey among 45 families, although it needs to elucidate the methodology employed in determining these houses. Were they chosen randomly or based on their representation of specific income levels or building types? This information is vital in determining if the survey findings can be applied to the entire region.

4. The result section contains complex data and might benefit from the inclusion of more graphic representations. For instance, the heating modes and expenses section provides intricate information that may be enhanced by including supplementary charts or graphs. For example, a bar graph that compares the heating expenses of different families or a pie chart that displays the proportion of households using different heating techniques would enhance the accessibility and ease of interpretation of the information.  However, the data does not thoroughly analyze the demographic composition of the surveyed homes.

5. The "Discussion" section is lacking in discussing potential obstacles to applying the offered techniques. This is important as it helps the reader understand the feasibility and applicability of the recommended techniques. The report recommends biomass stoves as a cost-effective carbon reduction solution but needs to address issues like Gannan's biomass supply or infrastructure. If biomass supply networks are undeveloped, the technique may not work.

Comments on the Quality of English Language

Not required 

Reviewer 2 Report

Comments and Suggestions for Authors

Abstract:

·       Are there any results to share regarding carbon emission savings when biomass was used? If yes, please add those numbers in there.

Introduction:

·       Great work with the research framework portion of the introduction.

Research Methods:

·       I would encourage the authors to either mention any climate zone details of the selected village or maybe provide a table with monthly average temperatures. This would help the readers understand the climatic conditions in a better way.

·       Also, please mention the source from where these temperatures were recorded.

·       Please mention the units of the dimensions in Figure 3.

·       Were only two days selected for the thermal testing? It might not be sufficient to draw any conclusions. It would be great to study the influence of temperatures over energy usage for at least an entire season.

·       In Figure 4, it looks like the surface temperatures of the wall was recorded only on one side of the building. This might not be a useful set of information to work with since the solar radiation could differ based on the wall locations.

·       Also to add, in Figure 4, why was only one window selected for temperature measurement?

·       Please add the specifications or model numbers of the sensors used including their accuracies.

·       How were the U-Values determined in Table 1? If any standard values of the materials were used, then please add the details of that source and create a table to list out the U-values of all individual materials.

·       Please add the HVAC equipment details.

·       How were the equations used in Section 3.3 derived? Using any field data or was it adopted from any previous studies? Please add the sources of these equations.

·       Please check the error on Line 152.

·       How was the energy consumed by various equipment obtained? Were there any sensors installed? Please add more details about that.

Results and Discussions:

·       How was the solar radiation value mentioned in Section 4.1.2 obtained?

·       No proper supporting data/findings/literature for the statements in Lines 261 through 264.

·       How were the heat losses calculated in Table 3 determined?

·       Which table are the authors talking about in Lines 281 and 282?

·       I would suggest replacing the word investment in Table 6 with operating cost.

Conclusions:

·       Proper data analysis required to draw the current conclusions.

Comments on the Quality of English Language

Found minor grammatical mistakes.