CO2 emission

I am interested in electricity generation and its impact on the environment.

I submitted a manuscript to Applied Energy but it was not accapted for publication (see reasons below). But I do not have time to update this publication due to my elevated duties as a group leader. I made the manuscript available here:

Carbon Intensity of the Global Electricity Production 

The Matlab Code to execute the calculations that are presented in this paper can be downloaded from here: 

Calc_global_FCI_electricity.zip (this zip file contains a .m file and 4 xlsx files for the time dependent parameters)

If you want to cite this research (please, consider first the reviewer reports below), you may do it the following way:

Zoltán Várallyay, "Carbon Intensity of the Global Electricity Production," preprint on ResearchGate (2022), DOI: 10.13140/RG.2.2.27849.42082

Reviewer reports:

Reviewer #2: This manuscript evaluates the full carbon intensity of the global electricity production, it has met the requirements of the paper, but the considerations of the article are incomplete. The specific comments are as follows:

1. In this study, predictions for the years from 2022 to 2025 is presented by extrapolating the corresponding parameter sets to this period of time. 

Energy policies will affect the structures of power production and power consumption, the author is suggested to consider the dynamic impacts of national policies in predicting the future global carbon intensity, in order to make the prediction results more accurate.


2. In the research of carbon intensity of the global electricity production, the author is suggested to consider the impact of the interaction between the power system and other energy sectors, such as electricity-heat and electricity-hydrogen system.


3. Many countries have published that renewable energy power generation systems must be equipped with energy storage facilities, but it may not be considered in this study. Can the author further explain whether the energy storage system will affect the assessment of carbon intensity?

4. The Abstract section is not properly representative of the entire paper. Please make sure that your abstract is properly structured and proof-read concerning English spelling and grammar.

5. The purpose and intended application of the research must be clarified in the paper as it is not clear in the current version of the paper. The Introduction section should make a critical analysis for more literature reviews, to highlight the significant contribution of this research to the carbon intensity field.

6. I believe a high-level flowchart can help better understating the proposed method and the sequence of steps which have been taken.


Reviewer #3: The study used a well-to-wheel approach, the FCI of electricity generation is evaluated as a global average in this paper the first time. The parameter sets of calorific value, carbon content of fossil fuels and efficiency of corresponding types of power plants were reviewed. This paper reviews the latest results of life cycle assessment (LCA) research and applies them to this analysis, including nuclear and renewable energy, as well as geothermal, marine power and waste incineration and other rare forms of energy power generation. But some concerns are given here.


1. Is there any reference source for the phrase "The final GHG emission value of LCA students are strongly dependent on the used GHG value of electricity. A trusted value for the total carbon intensity of electricity generation is a key for LCA students.".

2. The introduction section can briefly explain the LCA method.

3. For each item in the LCA list in the method section of Section 2, a diagram can be added to illustrate the logic between each item. More clearly express the main method flow of the whole article.

4. Section 3.2 refers to the generation capacity and proportion of solar and wind energy in 2019, 2020 and 2021, and lacks more realistic background explanation.

5. As for the differences between FCI and ACI in the conclusion, there is not much connection with the results and discussion.

6. There are some grammatical errors that need to be improved.

7. The contribution of this study is not so clear.

If you want to contact me regarding this research, please, use the following gmail address: zoltan.varallyay