IMO Standardized CII Calculator for International Shipping

Etive Mòr has released an open source implementation of the International Maritime Organisation (IMO)'s Carbon Intensity Indicator (CII). The software is aligned with IMO specifications required to adhere to MARPOL Annex VI regulatory measures, including MEPC.339(76), MEPC.364(79), and MEPC.337(76), and ISO standard 8217. 

The library accepts some metadata about the ship, including its weight category and weight (DWT or GT). The library then generates a multi-year backcast and forecast of the ship's CII rating out to 2030. 

The CII indicator aims to make the carbon intensity of any given ship easy to understand, transparent, and standardised. It does so by ranking all ships globally on an A to E rating (A being the best, E being the worst). Ship emission intensity calculations consider a mixture of weight, distance travelled in the calendar year, and the fuel used in their main engines. 

Grades are re-calculated annually. The boundaries of what is considered "good" is a moving target. This moving target is intended to encourage shipping firms to constantly improve the carbon intensity of their ships to 2030. The graph demonstrates the gradual tightening of the IMO's Carbon Intensity requirements over time. The nearer to 2030, the lower a ship's Attained CII must be to achieve an A grade.

The specification for this software can be found in IMO's resolution MEPC.354(78), adopted in June 2022.

The ship's Attained Carbon Intensity Index is compared to its Required Carbon Intensity Index to produce an easy to understand grade for the ship. The grading scheme is in the range A to E, where A is the most efficient bracket, C represents a ship at-or-near its CII, and E is the least efficient.

For further information, check out the software on GitHub. Contributions are welcome! https://github.com/Etive-Mor/Open-IMO-CII-Calculator 

For support or assistance integrating the software, get in touch directly.