This thesis is being written at a time of fundamental change for the global energy and industrial system. The climate crisis, as documented by the reports of the Intergovernmental Panel on Climate Change (IPCC,2023), requires an immediate and drastic reduction in greenhouse gas emissions. The European Union, through the Green Deal and the European Climate Law, has set a legally binding target of climate neutrality (Net Zero) by 2050.

However, the path to Net Zero is neither linear nor uniform for all sectors of the economy. While the power generation sector is achieving rapid decarbonisation through the penetration of Renewable Energy Sources (RES), heavy industry faces an existential impasse. Sectors such as cement production, oil refining, steelmaking, and fertilizer production are characterized as "Hard-to-Abate Sectors.". In these industries, carbon dioxide (CO2) emissions do not only come from the combustion of fossil fuels for energy, but are inherent in the chemical production process (process emissions). A typical example is cement production, where the conversion of limestone into clinker inevitably releases CO2, which cannot be eliminated even if the plant operates on 100% green energy (IEA, 2021).

The subject of the study is the CCS supply chain, in this context, Carbon Capture and Storage (CCS) technology emerges as the only viable solution for maintaining industrial production in Europe. The subject of this thesis is not limited to a technical description of carbon capture. Instead, it focuses on the study of CCS as an integrated supply chain system (Global CCS Institude,2022).

Research interest focuses on the design, sustainability, and strategic management of CO2 flow from source to sink. This chain includes three distinct nodes (IPCC, 2005):

• Capture & Conditioning: Separating CO2 at the source and converting it into liquid form.

• Transport: Moving the cargo via pipelines or ships.

• Storage: Permanent geological storage.

In particular, the study examines the case of Greece and the "Prinos CCS" project, which is being developed by Energean in the depleted oil field of Prinos, in Kavala. The choice of this particular topic was dictated by the strategic importance of the project, as it is the first attempt to create a storage hub in the Eastern Mediterranean, with the potential to serve not only domestic industry but also neighboring countries (Energean, 2023).

Although the literature on CCS is extensive at a technical level (mechanical), there is a lack of research approaching the subject from the perspective of logistics and strategy, particularly for the Mediterranean region. This paper fills that gap by answering some key questions (European commission, 2023):

• What's the best transport model (pipeline vs. shipping) for Greece's fragmented geography?

• Is the development of the chain economically viable under the current prices of the European Emissions Trading System (EU ETS)?

• What are the social and environmental risks and how can they be turned into opportunities in the context of a Just Transition?

The complexity of the problem, which spans technical, economic, and social fields, necessitated the adoption of a holistic research strategy. This dissertation does not limit itself to a one-dimensional technical description but adopts the philosophy of Pragmatism. This choice allows us to focus on practical results and combine different analytical tools to solve the central problem: the sustainability of CCS in Greece (Saunders el al., 2019).

The main research strategy chosen was a case study of the "Prinos CCS" project. This method was considered the most appropriate because it allows the phenomenon to be examined in its real-life context. Data collection was carried out through a systematic review of secondary sources (Secondary Data Review), drawing on technical reports from the European Commission, feasibility studies by Energean, and international literature in databases such as ScienceDirect and Google Scholar.

Data analysis was performed using the triangulation method, combining three analytical tools:

• Techno-economic Assessment (TEA): To calculate the life cycle cost and compare it with the prices on the emissions trading market.

• SWOT Strategic Analysis: To assess the opportunities and threats in the macro environment.

• Qualitative Social Analysis: To assess social acceptance and employment prospects.

The research initially confirmed that Greece possesses a rare geological advantage. The technology for storage in depleted hydrocarbon deposits (Depleted Oil & Gas Fields) is assessed at the highest level of technological readiness (TRL 9). The Prinos reservoir, consisting of sandstones and covered by impermeable layers of evaporites (salt), offers guaranteed impermeability. Unlike saline aquifers, where uncertainty is high, Prinos has 40 years of historical performance data, minimizing the risk of CO2 leakage (Saunders el al., 2019).

However, the most critical technical finding concerns the design of the supply chain. The geographical peculiarities of Greece (insularity, mountainous terrain, seismicity) make the development of an extensive network of land pipelines technically difficult and economically unviable. The research identified the "Hub and Spoke" model using maritime transport as the optimal solution. In this model (AI Baroudi et al., 2021):

• Spokes are emission sources (e.g., Titan Cement, ELPE Refineries) where CO2 is captured and liquefied.

• The "Hub" is the floating or fixed facility in Prinos.

• The connection is made via a "Virtual Pipeline" consisting of a fleet of liquefied CO2 carriers (LCO2 Carriers).

The analysis also highlighted the technical challenges of this model. Liquefying CO2 is an energy-intensive process. To make the gas liquid and transportable, it must be cooled (to -26°C for medium pressure or -50°C for low pressure) and compressed. It has been calculated that this process consumes approximately 90 to 120 kWh of electricity per ton, creating a significant "energy penalty." This finding leads to the conclusion that the sustainability of the system depends entirely on the availability of cheap, green energy. If liquefaction is carried out using energy from lignite or natural gas, the environmental benefits of the project are dramatically reduced (AI Baroudi et al., 2021).

About the Break Even Point and the necessity of the Economies of scales. The economic assessment was at the core of the research, as the success of CCS is ultimately judged in the marketplace. Through Levelized Cost of Storage (LCOS) analysis, the study determined the total cost of the chain (Capture + Transport + Storage) to be in the range of €65 to €120 per ton of CO2 (Global CCS institute, 2021).

The large discrepancy in costs can be explained by two factors (ZEP 2011):

• The source of CO2: Industries with high CO2 concentrations in their exhaust gases (such as ammonia or hydrogen production) have low capture costs (~€40/t). In contrast, power plants or cement plants have higher costs (~€80/t).

• Economies of Scale: The analysis showed that shipping costs decrease exponentially as volume increases. In the pilot phase (1 Mtpa), costs are high. At full scale (3+ Mtpa), the use of larger ships reduces marginal costs.

Comparing these figures with the price of emission allowances in the European Union Emissions Trading System (EU ETS), which ranges between €80 and €90 per ton, leads to the conclusion that the project is marginally viable. There is a clear "viability gap" in the early stages of implementation. The market alone cannot cover the high initial risk (CAPEX) of ships and infrastructure. Therefore, the study concludes that hybrid financing tools are needed. Carbon Contracts for Difference (CCfDs) emerged as the most critical support mechanism, as they guarantee investors a stable price, covering the difference when the ETS price is low (European Commission 2023).

Last but not least this research took into account the Environmental, Social Findings, and Strategy. The environmental analysis, based on the Life Cycle Assessment (LCA) methodology, confirmed that CCS is a necessary tool, but not a panacea without conditions. The system's Net Reduction Efficiency was calculated at 80-85% rather than 100% due to emissions produced by the transport ships and compression units themselves (Cuellar-Franca & Azapagic, 2015). In addition, the risks to the sensitive ecosystem of the North Aegean Sea were examined. The possibility of CO2 leakage from the subsea pipeline or injection point, although small, could cause local acidification of the water, affecting marine life. The research highlighted the need to install advanced monitoring systems (MMV), such as acoustic sensors and bubble detectors, the cost of which must be included in the project budget. With regard to induced seismicity, it was found that the use of a depleted field such as Prinos is safer than the use of aquifers, as the pressure in the reservoir is currently low and the injection of CO2 will simply restore it gradually to its original, natural levels.(Verdon et al., 2013)

In the field of social analysis, the thesis addresses the fear of the "Social License to Operate." While the risk of the NIMBY ("Not In My Backyard") phenomenon is real, the offshore location of Prinos acts as a protective shield, eliminating the visual disturbance that often causes reactions to onshore projects (Ashworth et al., 2012).

The most important social finding, however, is positive and concerns employment. CCS is emerging as the pillar of Just Transition for Greece. In an era of decarbonization, the project offers a double benefit:

• Job Security: It allows energy-intensive industries (cement, refineries) to continue operating under a Net Zero regime, saving thousands of jobs that would otherwise be lost due to relocation (carbon leakage).

• Creating New Jobs: The development of the Hub creates demand for specialized personnel (engineers, geologists, sailors). The research highlights the potential for reskilling the oil industry's workforce, transforming hydrocarbon expertise into carbon management expertise.

Furthermore, this opens up a huge opportunity for Greek shipyards, which can undertake the construction and maintenance of the LCO2 fleet(SINTEF, 2018).

The synthesis of all the above findings through strategic SWOT analysis leads to the final conclusion of the thesis: Greece must aggressively pursue the role of Regional Storage Hub. The surplus capacity of Prinos (100Mt) more than covers national needs (Energean, 2023). This creates an opportunity to provide storage services to neighboring countries that lack suitable geology (Bulgaria) or face saturation (Italy). Greek merchant shipping, which controls most of the global gas fleet, can realize this vision by creating a "maritime carbon corridor" in the Mediterranean (UGS, 2023).

The success of this venture will have multiple benefits: it will strengthen the competitiveness of Greek industry, create a new source of revenue from CO2 import and storage, and upgrade the country's geopolitical role in Europe's energy map. This paper aims to serve as a roadmap for understanding and implementing this national goal.