When Security Means Sustainability: A Comparison Between the Life Cycle Assessment of a Cybersecurity Monitoring Solution and the Environmental Impact of Cyberattacks

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript investigates the link between cybersecurity and environmental sustainability by comparing the carbon footprint of a cyberattack-induced outage at a 600 MWe CCGT power plant with the life cycle emissions of a cybersecurity monitoring solution. Using a stylized incident scenario, the authors estimate wasted fuel and corresponding CO₂ emissions and contrast these with a 5-year LCA of a monitoring architecture based on 1-10 Raspberry Pi units and a server. A simple probabilistic analysis then derives break-even attack probabilities under which the avoided emissions exceed the monitoring system’s footprint. The paper’s main contribution is to frame cybersecurity investment as a climate-positive measure in energy infrastructure, integrating power plant operational emissions and ICT LCA into a single comparative view.
Drawbacks:
1. The discussion mentions compensatory generation and less efficient backup sources, but these are not modeled. The emissions calculated for the attack scenario only reflect wasted fuel at the affected plant. Indirect system effects are not included, although they may be significant and could strengthen the central claim.
2. The monitoring solution is implicitly treated as fully effective when present. The expected avoided emissions are computed as if the monitoring system completely prevents a given outage with probability p. In practice, detection rates, false negatives, coverage of different attack classes, and residual risk are crucial. The current framing risks overstating benefits because it fails to distinguish between the probability of an attack and the probability of a successful attack, despite monitoring.
3. The scenario assumes the plant remains in spinning mode at a fixed idle fraction and that restart can be represented as 1 h at full load. In reality, start-up and minimum load behavior of CCGTs are complex and dynamic, depending on prior operating state, grid conditions, and technical constraints. The paper does not reference plant-level operational data, operator guidelines, or standard models to justify these specific parameters. This may raise questions about the representativeness of the numbers, even though they are likely in the correct order of magnitude.
4. Section 2 gives a good narrative overview of ICT emissions, cyber-physical risks, and green hacks, but it does not systematically position this work among neighboring studies. A clearer mapping would underline novelty more convincingly.
5. The paper mentions cyberattacks and references real cases, but it never clearly states the assumed adversary capabilities and attack vector for the scenario. For a cybersecurity-focused audience, an explicit threat model is important, even if simplified.
Recommendations:
1. Consider at least one non-gas technology to illustrate how the framework transfers to other contexts.
2. Provide ranges or confidence intervals for key parameters.
3. Use simple Monte-Carlo or scenario ranges to show the spread of possible break-even probabilities. This would significantly increase the credibility of the quantitative claims.
4. Re-express the break-even probability in terms of the risk reduction attributable to the monitoring system, which would align more naturally with how cybersecurity investments are evaluated.
5. Rewrite the energy/emissions equations with explicit unit conversions and include a short numerical worked example in the appendix or main text so the reader can replicate one line of Table 2.
6. Briefly explain how a monitoring system like WatchField would detect such an attack in practice, even if only qualitatively.
7. Include a short discussion of scenarios where monitoring fails or only partially mitigates the incident and how that would modify the calculations.

Author Response

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Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

1. Summary of the manuscript & key contributions

• The paper explores the link between cybersecurity and environmental sustainability, that is, a relationship that is often mentioned conceptually but rarely quantified.
• It compares two things numerically:

1. the carbon emissions produced by a 12-hour outage of a 600 MW CCGT plant caused by a cyberattack,
2. the 5-year life-cycle emissions of a Raspberry-Pi-based monitoring system.

• The main contribution, as I understand it, is the claim that preventive cybersecurity can be climate-positive, the emissions from installing monitoring are far lower than the emissions resulting from a single forced outage.
• The manuscript presents a clear framework and the main argument is easy to follow, supported by tables summarizing the emission estimates.

2. Assessment of the methodology & analysis

• The approach is straightforward, but the study relies heavily on one scenario with fixed parameters (600 MW plant, 12-hour disruption, Italian grid mix, Raspberry Pi nodes). This makes the result illustrative rather than generalizable.
• The emission calculation for outage conditions is transparent, and the math can be followed easily. However, the restart assumptions and idle percentages could use clearer justification or supporting data.
• The LCA section is readable but simplified: no ISO boundary definition, no uncertainty ranges, disposal phase excluded without numeric support, and the embodied emissions of the server are not broken down.
• Using only the Italian electricity carbon intensity limits transferability to other contexts where grids are greener or dirtier. A multi-region comparison or at least commentary would strengthen credibility

3. Suggestions for improvement

• Strengthen the research gap in the introduction. To explicitly identify what previous work lacks and how this paper fills that gap.
• Add sensitivity or uncertainty analysis (vary outage duration, plant power rating, idle fraction, grid carbon factor, number of devices, etc.).
• Provide more detail for the LCA:

1. reference ISO 14040/14044,
2. define system boundaries,
3. include disposal/end-of-life or justify exclusion numerically,
4. break down embodied emissions of the server hardware.

• Include a brief discussion on when monitoring may not yield net savings.
• Consider addressing limitations and adding a future work section pointing toward extension to other infrastructure types (e.g., hydroplants, refineries, grids) or integration with real operational data.

 

Author Response

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Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The LCA methodology and system boundaries are not clearly defined.

The scenario assumptions are insufficiently explained.

Integration with the literature is very weak.

Using a single metric (only CO₂) limits the study.

There is no sensitivity analysis.

The LCA components of the monitoring system are presented superficially.

Author Response

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Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors

The manuscript addresses an underexplored and timely topic: the environmental consequences of cyberattacks on industrial energy systems, and how these impacts compare to the life-cycle footprint of cybersecurity monitoring infrastructure. The paper is well structured, the narrative is straightforward, and the authors present an illustrative quantitative scenario involving a CCGT power plant. The overall message—that cybersecurity investment can also be a climate-positive strategy—is interesting and relevant to the MDPI journal Sustainability's readership. However, the study has several methodological issues and simplifying assumptions that weaken the robustness of the conclusions. The CCGT outage model is overly simplified, the LCA methodology lacks transparency, and the monitoring system’s environmental footprint appears underestimated—particularly due to the incomplete modelling of server hardware. The probabilistic analysis is based on arbitrary attack probabilities without empirical justification. The discussion could be expanded, and the literature review could be deepened, especially in the OT/ICS cybersecurity domain. The manuscript has potential, but requires improvements before acceptance. I have the following notes for the authors to improve their manuscript:

1. The CCGT outage scenario is oversimplified and lacks referenced operational data. Values such as 10–25% idle load, 12-hour forced idle, and 1-hour restart must be supported by technical sources or manufacturer/utility documentation. Please consider revision.

2. The LCA methodology is incomplete and does not follow ISO 14040/44 guidelines. The study lacks a functional unit, an impact assessment method, and transparency regarding data sources and system boundaries. Please consider revision.

3. The environmental footprint of the monitoring server is significantly underestimated. A “medium-performance rack server” typically consumes 150–600 W and has substantial embodied emissions, which are not reflected in Table 3. Please consider supplementation.

4. Attack probability values (0.1–10%) used in the probabilistic analysis are arbitrary. The authors should support these probabilities with empirical data from ENISA, ICS-CERT, CISA, or similar sources.

5. The literature review needs expansion, especially on OT/ICS cyber incidents and cyber-physical impacts. Important cases such as Stuxnet, Industroyer, and Triton are missing, as well as studies on cyber-induced load imbalance.

6. The analysis focuses solely on CO₂ emissions and omits other relevant environmental impact categories. Even a brief multi-impact discussion (e-waste, resource depletion, energy use of server infrastructure) would align better with Sustainability. Please consider supplementation.

7. Please check, complete definitions for all parameters in equations.

8. The discussion and conclusions are overly general and repeat content from earlier sections. Consider strengthening the limitations and clarifying how these assumptions affect the robustness of the presented results.

I propose to accept the manuscript after revision.
I wish the authors success.

Author Response

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Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

Thanks for the authors' effort to make this revision. All my comments are fulfilled.