Introduction:
The Decarbonization Challenge
The global maritime industry, the backbone of world trade, faces immense pressure to decarbonize. With shipping responsible for approximately 3% of global CO2 emissions, the International Maritime Organization (IMO) has established a mandatory framework to reduce Greenhouse Gases (GHG). Key regulations like the Energy Efficiency Existing Ship Index (EEXI) and the Carbon Intensity Indicator (CII), effective since January 1, 2023, are pushing the industry towards innovative energy-saving technologies. My Integrated Master's thesis addressed this challenge directly by conducting a techno-economic analysis of retrofitting a bulk carrier, the "Wadi Alkarm," with six Flettner rotors. The objective was to quantify the real-world impact of this Wind-Assisted Propulsion System (WAPS) on its performance, regulatory compliance, and operational viability. The study yielded three critical findings.
Significant Fuel Savings & Emission Reduction
The most immediate impact of installing the six Flettner rotors was a drastic reduction in the vessel's environmental footprint. My analysis concluded that the technology leads to:
- 30% Annual Main Engine Fuel Savings, which translates to 1,452 fewer tons of fuel consumed each year.
- A 27.6% reduction in annual CO2 emissions, preventing 4,522 tons of CO2 from entering the atmosphere annually.
- A ~27.64% improvement in the ship’s Carbon Intensity Indicator (CII), a critical metric for long-term compliance.
These findings confirm that Flettner rotors are one of the most effective WAPS available, offering substantial and quantifiable environmental benefits.
A 9-Year Extension of the Vessel's Operational Lifespan
This is the most critical finding from a shipowner's perspective. Without the Flettner rotors, the "Wadi Alkarm" would have become non-compliant and commercially unviable by 2025.
Before Retrofit: The vessel failed to meet the required EEXI (4.48 achieved vs. 3.516 required) and was projected to receive a failing “E” rating on its CII from 2025 onwards, forcing it out of service.
After Retrofit: The installation of the rotors immediately brought the vessel into compliance. The achieved EEXI dropped to 3.463 (a passing score), and the improved CII rating ensures the ship can operate efficiently until at least 2034.
This represents a 9-year extension of the vessel’s profitable operational life, transforming a regulatory threat into a strategic advantage.
A Sound Financial Investment with Across-the-Board Benefits
Beyond compliance, the study concluded that retrofitting Flettner rotors is a highly valuable financial investment. The significant fuel savings ensure that the initial cost of the technology is expected to be fully amortized well before 2034, leading to several years of pure profit from reduced operational expenses.
Furthermore, all energy efficiency indicators showed remarkable improvement:
- The Energy Efficiency Operational Indicator (EEOI) improved dramatically from 5.13 to 3.71, earning the vessel the maximum 27-point rating under the Clean Shipping Index (CSI).
- Across the board, the technology demonstrated its power, with reductions of 22.7% in EEXI, 27.7% in EEOI, and 27.6% in CII.