The preservation of perishable foods, particularly fish, requires careful management at every stage of the supply chain, from capture to consumption. Cold storage facilities are essential for maintaining optimal conditions, including precise control of temperature and humidity. However, these facilities often face significant challenges due to their high energy consumption, leading to increased operational costs. To address this issue, adopting energy-efficient strategies, such as advanced refrigeration technologies and real-time monitoring through automation, is crucial. This study examines an innovative cold storage system in Tarrafal, Santiago, Cape Verde, that integrates wind, solar, and tidal energy sources. The key objectives are to evaluate energy efficiency, financial viability, and environmental impact under four solutions. In solution 1, two R134a refrigeration units operate on conventional grid power. Solution 2 utilizes a transcritical CO2 system, also powered by the grid. Solution 3 combines CO2 refrigeration with independent renewable energy, and Solution 4 uses CO2 refrigeration alongside seawater heat exchange and autonomous renewable energy. The results strongly favor Solution 4, showing emissions of 15,880 kg CO2eq and a return on investment within five years. This solution reduces emissions by over 90% through autonomous energy generation. Although requiring higher upfront investment, Solution 3 also proves financially viable, significantly contributing to long-term energy sustainability. The renewable energy production in this solution cuts emissions by over 600,000 kg CO2 compared to traditional systems, underscoring the environmental benefits of integrating local renewable energy sources.