Modernization Roadmaps for Existing Buildings under Limited Energy Resources and Craftwork Capacities

Round 1

Reviewer 1 Report

1. The summary of the article is too long, does not encourage reading the whole article, and is also inconsistent with the requirements stated in the author's instructions. It does not provide an objective presentation of the article, for example, it does not discuss the research purpose or main findings and interpretations.
2. Please clearly define the aim of the study.
3. What constitutes the novelty of the conducted research is not clearly highlighted in the introduction.
4. The methodology is described correctly but in a very general manner.
5. In the methodology, you describe energy models of the building, but nothing is derived from them. What is the objective function - energy consumption reduction, useful, final, or primary energy? Or maybe the maximization of CO2 emission reduction? Does the model take into account the aspect of cost-effectiveness resulting from energy efficiency improvement, which is closely related to costs? Is a parameter like the cost of saved energy considered? After all, there are buildings in which thermal improvement is not cost-effective due to high modernization costs. This is not specified in the model constraints, and if such a specification exists, it should be visible to the reader.
6. What do we understand by the term "inefficient energy buildings"? On what basis was it determined that 75% of buildings are inefficient? There is no information about it in the literature review. From what level of consumption, according to the authors, is a building considered efficient? What do you aim to achieve through the conducted optimization? Will it be possible to classify (prioritize) buildings in terms of their importance and the order in which they should undergo modernization in subsequent years?
7. When you mention craftwork capacities, is it a matter of convention, or does the optimization model take into account the law of supply and demand? With an increase in demand for a particular good or service, the number of entities providing services also increases. Does the model consider the production and service capacities of the local market, or do you also assume the flow of goods and services from other countries? Please clarify this.
8. Chapter 3. Application to a typical residential building. This is a very general approach. What type of building is it? What are the areas of the external partitions, the heated volume, the exposure, the heat transfer coefficients, and the components of the heating system? What type of gas boiler is used - open, closed combustion chamber, or condensing boiler? What costs have been assumed for modernization actions - material costs, labor costs, energy costs, etc.? There is no way to verify the calculations performed.
9. The conclusions are not based on research results; in my opinion, they are general, journalistic statements without supporting research findings. They need to be clarified. You have created an interesting optimization model, but what specific purpose does it serve? The key finding is that the electrification of heat supply should also be implemented with limited craftwork capacities, as it leads to higher costs and emissions. Many years ago, I attended energy management studies, and one of the topics discussed was the issue of limited capacities of generation and transmission equipment in the power system. The conclusions from those classes were exactly the same as you have written, and that was without any special optimization in the article - where is the novelty of the research here?

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

The authors demonstrated their expertise in the field, it is a very interesting paper. However, I have the following comments:

 

In the abstract mention the case study you analyzed and the results of that case study.

Line 77 page 2: If you did not conduct the interviews, it is incorrect that you mention, "Therefore 90 expert interviews were conducted to collect this data". As I understood in your paper, that is existent information from a public database, so please correct that and be explicit, mention that you obtained that information, not that you collected. 

Add a discussion section. I want to read about the implication of this proposal and its implementation in energy-building simulators such as EnergyPlus. Do you consider using this method within the EnergyPlus structure a viable option? 

Please discuss more the limitation of your proposal; what are the advantages of another modernization roadmap? 

In the discussion section, you can add references. However, in the conclusion section, you must avoid those references. Please correct that by having a dedicated discussion and conclusion sections.

 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The authors have taken into account the reviewer's comments so I recommend the manuscript for publication