Three little letters, one big impact. The Carbon Intensity Indicator (or CII as its more commonly known) is one of the IMO’s principal tools for accelerating decarbonization, helping shipping companies assess, understand and work to drive down vessel emissions. Introduced in 2021, becoming mandatory in 2023, the measure tracks how much CO₂ a ship emits per cargo carried over distance sailed. It sounds simple, but it pays to dive deeper for a comprehensive understanding – including how the adoption of breakthrough technologies, such as suction sails, can empower simpler, cost-effective compliance.
What is the Carbon Intensity Indicator (CII)?
At its core, CII is a simple concept: it measures how efficiently a vessel carries cargo in relation to the CO₂ it emits. The result is then translated into an operational rating from A (major superior performance) to E (inferior performance). This rating isn’t just cosmetic; it has real operational implications. Ships rated D for three consecutive years, or E for one year, must submit a corrective action plan, demonstrating how they will reach at least a C rating.
As you’re probably aware, the ratings represent ‘moving targets’ with more restrictive emission limits every year. This makes it harder to comply, essentially forcing vessels to take action to drive down emissions as we all, collectively, set sail for ‘net-zero’ in 2050. (....)