An Energy Efficiency Existing Ship Index (EEXI) calculation and compliance screening tool: Development, verification, and benchmark comparison

Abstract

The Energy Efficiency Existing Ship Index (EEXI), mandatory under MARPOL Annex VI since January 2023, requires existing ships to demonstrate a design-efficiency level that a large share of the conventionally configured fleet cannot meet without intervention. The tools available to evaluate and plan for compliance, however, are limited: certification grade calculators are proprietary and opaque, while academic treatments tend to embed the computation within one-off scenario studies rather than provide a reusable, openly described instrument. This paper presents the development and preliminary verification of an open, single-file, offline capable web based tool for EEXI calculation and compliance screening. The tool implements the attained-EEXI method of IMO Resolution MEPC.333(76) for the twelve applicable ship types, computes the required EEXI and a quantitative compliance verdict, models the engine and shaft power-limitation (EPL/ShaPoLi) regime, and estimates, for non-compliant vessels, the limiting rating that would bring the attained index to the required value. This was developed under the V-Model methodology, which embeds verification and validation as a structural counterpart of each design stage. Software verification and external validation are reported separately. For verification, two independently written implementations of the governing equations agreed to machine precision (ε ≤ 10⁻¹² %) across a thirteen-vessel matrix of hypothetical test cases spanning ship types, sizes, regulatory boundaries, and the power-limitation regime, and the inverse solver converged to the intended root; this establishes internal consistency of the encoding, not regulatory correctness. For external evidence, the outputs are compared with a published worked example (≈0.2 % deviation) and found to be consistent with an established commercial calculator and with the peer-reviewed literature. Validation against certified EEXI Technical Files has not yet been performed and is reserved for a planned fleet-level study. The tool offers a transparent, auditable decision-support instrument of particular value to smaller operators and developing maritime economies, and a transferable template for verifying regulatory calculation software.

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Cite this article:

APA Style:
Rinaldi, A., Barasa, L., Suranta, N., & Wibowo, T. A. (2027). An Energy Efficiency Existing Ship Index (EEXI) calculation and compliance screening tool: Development, verification, and benchmark comparison. Maritime Technology and Research, 9(1), 290489. https://doi.org/10.33175/mtr.2027.290489

MDPI Style:
Rinaldi, A.; Barasa, L.; Suranta, N.; Wibowo, T. A. An Energy Efficiency Existing Ship Index (EEXI) calculation and compliance screening tool: Development, verification, and benchmark comparison. Marit. Technol. Res. 2027, 9, 290489. https://doi.org/10.33175/mtr.2027.290489

Vancouver Style:
Rinaldi A, Barasa L, Suranta N, Wibowo TA. (2027). An Energy Efficiency Existing Ship Index (EEXI) calculation and compliance screening tool: Development, verification, and benchmark comparison. Marit. Technol. Res. 9(1):290489. https://doi.org/10.33175/mtr.2027.290489

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Highlights

• Open single-file EEXI tool implements IMO MEPC.333(76) for twelve ship types.
• V-Model embeds verification as a structural counterpart of every design stage.
• Two independent implementations agree to machine precision on 13 test vessels.
• Inverse solver estimates the minimum engine power limit restoring compliance.
• Benchmark comparison against a published example deviates by about 0.2 percent.