(a) EEDI – Energy Efficiency Design Index

• The EEDI is a mandatory technical measure under MARPOL Annex VI for all new ships of 400 GT and above, aimed at reducing greenhouse gas (GHG) emissions from the design stage.
• It expresses a ship’s CO₂ emissions per tonne-mile, setting minimum energy efficiency levels for various ship types and sizes.
• Encourages design improvements such as optimized hull forms, energy-saving devices, and efficient propulsion systems.
• The required EEDI value becomes progressively stricter in phases (every 5 years).
• It is non-prescriptive, allowing shipbuilders the freedom to choose technologies to achieve compliance.
• Ensures all newly constructed vessels meet improved energy efficiency standards over time.

(b) EEOI – Energy Efficiency Operational Indicator

• The EEOI is a voluntary operational measure used to monitor a ship’s fuel efficiency during voyages.
• Represents the amount of CO₂ emitted per unit of transport work, generally expressed as grams of CO₂ per tonne-nautical mile.
• Calculated from actual operational data — fuel consumption, distance sailed, and cargo carried.
• Provides feedback for ship operators to enhance voyage planning, trim optimization, and fuel management.
• Enables performance comparison over time, helping identify operational improvements.
• Supports continuous enhancement in fuel efficiency and emission reduction practices.

(c) Enhanced SEEMP – Ship Energy Efficiency Management Plan

• The SEEMP is a mandatory management plan under MARPOL Annex VI Regulation 26, designed to improve ship energy efficiency.
• The Enhanced SEEMP (Part III) became mandatory from 1 January 2023.
• It consists of three parts:
  • Part I: Ship-specific energy efficiency improvement measures.
  • Part II: Data Collection System (DCS) for annual reporting of fuel oil consumption.
  • Part III: CII (Carbon Intensity Indicator) compliance plan, including annual targets and corrective actions.
• The enhanced SEEMP ensures an integrated link between design, operation, and performance monitoring, promoting continuous improvement in a ship’s energy and carbon efficiency.

(d) CII – Carbon Intensity Indicator

• The CII is a mandatory operational rating system, effective from 1 January 2023, assessing a ship’s annual CO₂ emissions relative to its transport work.
• Applies to all cargo ships, Ro-Pax vessels, and cruise ships above 5,000 GT engaged in international trade.
• Each ship receives an annual rating from A to E —
  • A: Excellent efficiency
  • E: Poor efficiency
• The attained CII (actual operational performance) is compared against the required CII (IMO benchmark improvement goal).
• Ships rated D or E for three consecutive years must submit a corrective action plan within their SEEMP.
• Aims for year-on-year reduction in carbon intensity, aligned with the IMO’s GHG reduction strategy through 2050.