Following the April agreement at MEPC83 on the package of new greenhouse gas emissions reduction regulations – known as the IMO net-zero framework (NZF) – IAPH is further revising the expanded suite of performance modules planned for the Environmental Ship Index (ESI).
Previously scheduled to come online in 2026, ESI’s revised and expanded offering will now be further adjusted to align with and incorporate the requirements of the IMO NZF and the expectations of the global maritime and port industries.
These changes will take into account a range of potential emissions, introduce a new GHG methodology, and reward innovation and application of zero-emissions techniques onboard vessels. The new ESI Core module will now come online at the beginning of 2027, following further significant revision of formulae, including the introduction of the new GHG emissions calculation.
In its revised format, ESI will remain consistent with the approach with which Incentive Providers and Incentive Receivers are familiar, supporting ports and vessel owners on the journey to decarbonisation and lowering emissions.
The transition process will continue through 2025 and 2026, with support from ESI’s Board and administrator, as well as IAPH, ensuring ample support and time to facilitate a smooth migration for the scheme’s Incentive Receivers and Incentive Providers.
ESI will continue to reward those vessels that exceed current IMO emissions standards, now and into the future. ESI is the global benchmark and industry standard tool for incentivising environmental performance. It has been recognised by the IMO as the standard basis for port incentives for low- and zero-carbon ships. The index was created by major ports in cooperation with the IAPH and has been fully integrated into the IAPH’s governance structure since 2020.
In addition to air quality and GHG emissions, ESI also addresses global concerns about the environmental impact of vessels on marine life. From 2026 ESI will offer a new option to reward the mitigation of underwater radiated noise – a change that is unaffected by decisions at the IMO in April.
For more information on IAPH’s Environmental Ship Index (ESI): click here
To visit the ESI website, please navigate to the portal homepage and frequently-asked questions (FAQ) section.
About IAPH
Founded in 1955, the International Association of Ports and Harbors (IAPH) has developed into a global alliance of 192 port authorities as well as 168 port-related businesses. Comprised of over 80 different nationalities across the world’s continents, member ports handle over one third of the world’s sea-borne trade and well over 60% of the world container traffic. IAPH leads global port industry initiatives on decarbonisation and energy transition, risk and resilience management, and accelerating digitalisation in the maritime transport chain. The IAPH’s World Ports Sustainability Program has grown into the reference database of best practices of ports applying the UN Sustainable Development Goals and integrating them into their businesses - iaphworldports.org.