Novel Methodology to Assess Advanced Biofuel Production at Regional Level: Case Study for Cereal Straw Supply Chains
Round 1
Reviewer 1 Report
The authors developed a methodology to assess biofuel production at regional level and seems to have potential to apply in other areas. A few points for authors to consider:
1. I don't see the reasoning presented for spatialization. Is that based on transportation? location of production plan? location of source?
2. The authors will use CONVERGE to produce biofuel. Not necessary in much detail but I'd like to see more induction on this technology in the context.
3. The authors should keep the number format consistent across the manuscript, for example, table 6 and table 7: 123,456.89 vs. 123.456,89
Author Response
The authors developed a methodology to assess biofuel production at regional level and seems to have potential to apply in other areas. A few points for authors to consider:
- I don't see the reasoning presented for spatialization. Is that based on transportation? location of production plan? location of source?
Thanks for evidencing that this aspect is not clear in the text. Spatial analysis based on a GIS approach represents an appropriate tool for attaining a detailed biomass supply analysis. Several studies have used GIS and spatial analysis instruments as tools for biomass chain evaluation at the European, national, and local levels (Sacchelli, 2013).
In this paper spatialization deals with the analysis of site-specific non-technological barriers such as feedstock availability and accessibility assessment, biomasses conventional uses and feedstock competition, logistic of the operational phases, etc. Therefore, the regional breakdown of these indicators assesses which suitability degree can be assigned to a given area with a given type of biomass, its availability (kt/y) and certain logistics to supply a commercial-scale conversion plant. This allows to identify the most promising condition related to the needs of the specific technology and contribute to the selection of a proper plant capacity (e.g. 200 MWth or less).
The concept has been clarified in Section 2.3.
- The authors will use CONVERGE to produce biofuel. Not necessary in much detail but I'd like to see more induction on this technology in the context.
A brief description of the process structure and of its positioning in the biodiesel supply chain has been included in the Introduction.
- The authors should keep the number format consistent across the manuscript, for example, table 6 and table 7: 123,456.89 vs. 123.456,89
The numerical format in the manuscript is now coherent. The chosen format is: 123,456.89
Reviewer 2 Report
The authors analyzed cereals straw supply chains for commercial application in different European regions, regarding biomass availability, suitability analysis, regionalization and Multi Criteria Analysis. The paper is well structured and results are appropriately discussed. The following issues need to be revised:
1. Expand Abstract with the main results of the paper.
2. The last sentence in the Abstract in very long, condense/split it.
3. Page 2. „In this framework, this paper proposes a new methodology…” – Supplement the Introduction with descriptions of existing methodology for biomass supply chain from the literature on this topic. This is important to clearly point out the novelty of the proposed methodology in comparison to existing ones.
4. Better define the title of Section 3 (Cereals Straw Case Study), for example: ”Case study for cereals straw supply chains”.
5. Table 2. What about fix carbon and volatile matter. Those values are not presented in the Table.
6. Figure 3 is not explained in the main text. Revise that.
7. Note that you have two Tables 3 on page 8. The second should be Table 4? Check.
8. Enhance the visibilities (fonts) of x and y labels on Fig. 5.
9. Figure 6 is not readable. Correct.
Author Response
The authors analyzed cereals straw supply chains for commercial application in different European regions, regarding biomass availability, suitability analysis, regionalization and Multi Criteria Analysis. The paper is well structured and results are appropriately discussed. The following issues need to be revised:
- Expand Abstract with the main results of the paper.
Thanks for the remark. We added the following sentence that sums up the main numerical outcomes of the case study:
Central Europe and Mediterranean districts are those with the highest cereals straw bioeconomic potentials which allow mono-feedstock supply chains and relatively high capacity of the CONVERGE technology as 200 MWth and beyond. Central EU has an overall bioeconomic potential of 16.249 kt (232.359 TJ) distributed over 36 regions and organized in 12 BSRC. Mediterranean district has an overall bioeconomic potential of 3541 kt (50.630 TJ) dis-tributed over 9 regions and organized in 4 BSRC.
- The last sentence in the Abstract in very long, condense/split it.
The sentence has been split for increasing readability.
- Page 2. „In this framework, this paper proposes a new methodology…” – Supplement the Introduction with descriptions of existing methodology for biomass supply chain from the literature on this topic. This is important to clearly point out the novelty of the proposed methodology in comparison to existing ones.
The Introduction has been improved, adding information about the conversion process considered. In addition, some more details have been given about the innovative approach here used for allocating resources.
The proposed methodology has been designed for the comparison and the selection of the most profitable biomass supply chain for feeding a flexible and not feedstock-specific technology for bioenergy. In the present paper the case study of the cereals’ straw will be implemented as residual biomass available in all the EU regions, which allow mono-feedstock supply chains and relatively high capacity of the CONVERGE technology as 200 MWth and beyond. The selection of a proper feedstock and the evaluation of its availability represents a very important key aspect of the CONVERGE Project because these studies and research on the biomasses are conducted at early stage together with the deployment of the biomass conversion technologies to TRL 5. The selection of the most promising location for implementing a full-scale technology at demonstration stage, commercially not available, it is quite challenging mainly if the process scheme is very flexible and not feedstock-specific, as CONVERGE concept is, allowing a wide range of biomass feedstock to be considered in its processing, e.g., ligno-cellulosic residues from agriculture, forestry and industrial activity, or waste.
In general, the existing studies focus on net availability of a single investigated biomass as technical potential excluding the comparison of different biomasses supply chains and their logistical aspects and/or local factors as settlements structure, etc. Indeed, studies that use consistent data and methodology to estimate total technical availability of cereals straw or other ligno-cellulosic residues from agro-forestry sectors for bioenergy uses are quite common. As well as GIS-based assessment of cereal straw energy resource in the European Union has been widely applied in the field of bioenergy installations [10,25,31,32].
In the presented methodology the use of different biomasses with different seasonality and multi-feedstock supply chain is considered for a certain technology, such as CONVERGE. This is made possible by the application of the MCA approach that take in consideration beyond the technical potential of the biomasses their seasonality and the logistic complexity of the related supply chains. The MCA’s results, when combined with techno-economic evaluation of the technology in object can be useful decision tool for the choice of the most profitable solution.
- Better define the title of Section 3 (Cereals Straw Case Study), for example: ”Case study for cereals straw supply chains”.
As suggested, the title has been modified.
- Table 2. What about fix carbon and volatile matter. Those values are not presented in the Table.
In the Table 2 are indicated the parameter which are useful to MCA and LCA. Therefore, the complete proximate analysis of feedstock wasn’t considered for our purposes, including fix carbon and volatile matter.
- Figure 3 is not explained in the main text. Revise that.
The Figure is now introduced by the following sentence:
In the Figure 3 is briefly illustrated the fundamental steps of the logistical aspects of the cereals strow supply chain.
- Note that you have two Tables 3 on page 8. The second should be Table 4? Check.
The caption of Table 4 was wrong. Thanks for evidencing the typo.
- Enhance the visibilities (fonts) of x and y labels on Fig. 5.
- Figure 6 is not readable. Correct.
Figure 5 and 6 have been improved.
Reviewer 3 Report
Authors should improve their work based on the following suggestions
1. All abbreviations should be clearly defined and avoid abbreviations in the abstract (e.g. MCA, EU, etc)
2. Table 2 that presents the LHV, elemental analysis should be redrawn. Also, I believe its decimal points and not comas
3. In Table 1, how did the authors arrive at the indicators and the scores attached to them? is there any reference to support this?
4. There are typos here and there. Authors should improve the language
5. Figure 2 should be improved and the tags (C1100, C1200....)should be defined to help understand the work.
6. I think Table 4 is labeled as Table 3. Also, authors could redrawn the table rather than presenting it in Figure format.
7. The conclusions should be brief and highlight the findings of the study.
Author Response
Authors should improve their work based on the following suggestions
- All abbreviations should be clearly defined and avoid abbreviations in the abstract (e.g. MCA, EU, etc)
In the journal template, no acronyms section is indicated. All the acronyms are defined at the first use and recalled in the text. If required by the editor, we’ll add the acronyms list. They have been also removed from the abstract, as suggested.
- Table 2 that presents the LHV, elemental analysis should be redrawn. Also, I believe its decimal points and not comas
In the Table 2 are indicated the parameter which are useful to MCA and LCA. Therefore, the complete proximate analysis of feedstock wasn’t considered for our purposes, including fix carbon and volatile matter. Numbers format has been levelled out in the paper.
- In Table 1, how did the authors arrive at the indicators and the scores attached to them? is there any reference to support this?
The indicators have been selected and listed on the basis of the over ten years long experience related to the supply chains analysis of the authors applied to the goals foreseen for the specific task of the project (Task 6.2). Moreover, the scores and their ranges have been chosen both on the basis of the literature analysis for the MCA and for the investigated supply chains, as indicated in the introduction and in the methodology paragraphs, then on the answers to the questionnaires received as result of the stakeholder’s engagement activity. A brief paragraph has been added in the document.
- There are typos here and there. Authors should improve the language
The text has been checked and typos corrected.
- Figure 2 should be improved and the tags (C1100, C1200....) should be defined to help understand the work.
Description of tags are the labels in the boxes. The caption has been improved to explain it.
- I think Table 4 is labeled as Table 3. Also, authors could redrawn the table rather than presenting it in Figure format.
The numbering of the tables contained a typo. Thanks for noticing.
Tables 4 and 6 are not anymore in figure format.
- The conclusions should be brief and highlight the findings of the study.
Conclusions have been rephrased and shortened to evidence the outcomes of the model applied to the case study (cereals straw): Central Europe and Mediterranean districts are those with the highest cereals straw bioeconomic potentials. Details about the regional clustering results are also given, as well as multi-feedstock implications.
Round 2
Reviewer 2 Report
All my comments are addressed. My recommendation for this paper is: Accept.
Reviewer 3 Report
The authors have done much work to improve the manuscript. I think it can be accepted in this format.
