The International Maritime Organisation’s (IMO) proposed Net Zero Framework (NZF) is set to become one of the most significant regulatory developments in shipping. While it is still in draft form and awaiting adoption in October 2025, the framework aims to simplify and standardise the industry’s pathway to achieving net zero greenhouse gas (GHG) emissions by around 2050.
Before we get into the topic, we'd like to shed some light on some of the common abbreviations found.
GHG: Greenhouse Gas
IMO: International Maritime Organisation
NZF: Net Zero Framework
MEPC: Marine Environment Protection Committee
ZNZ: Zero or Near Zero
TtW: Tank to Wake
WtW: Well to Wake
Shipping moves over 80% of global trade by volume and, despite being the most carbon-efficient mode of cargo transport, still accounts for roughly 3% of global GHG emissions. With shipping demand projected to grow by 50% by 2050, the pressure to reduce emissions is mounting - not just from regulators, but also from cargo owners, charterers, and financiers linking emissions performance to lending.
The Paris Agreement’s temperature goals underpin this work, with the IMO recognising both CO₂, methane (CH₄), and nitrous oxide (N₂O) as major climate-warming gases, alongside pollutants like NOx, SOx, particulate matter, and black carbon.
The Net Zero Framework is designed to:
A major shift is that regulations will now cover the entire fuel value chain, known as Well-to-Wake (WtW)emissions. This includes fuel production, refining, distribution, and onboard combustion - offering a more accurate picture of a fuel’s true climate impact. All fuels will need a certified Fuel Lifecycle Label (FLL) with a Greenhouse Gas Fuel Intensity (GFI) score.
The regulations introduce two tiers of compliance, Base and Direct, requiring progressively tougher GFI targets from 2028 to 2050. Ships may use lower-GFI fuels to meet targets or pay penalties for shortfalls, with revenues reinvested into clean-fuel development, infrastructure, and training.
While many see the NZF as a vital global step, some argue it is too lenient compared to earlier climate goals. Others feel it is overly ambitious and complex, pointing to uncertainty over enforcement, alignment with regional schemes like FuelEU Maritime, and the availability of sustainable fuels.
One of the biggest changes in the IMO’s Net Zero Framework is the move from regulating only onboard emissions (Tank-to-Wake) to a full Well-to-Wake (WtW) approach.
Well-to-Wake covers all greenhouse gas emissions generated during a fuel’s lifecycle:
The calculation, known as a Life Cycle Assessment (LCA), is certified by Sustainable Fuels Certification Schemes (SFCS) recognised by the IMO. Fossil fuels will be assigned conservative default values, while sustainable fuels will be assessed on specific production pathways.
The GFI measures annual GHG emissions (in gCO₂eq) per unit of energy on a ship, on a Well-to-Wake basis.
Ships meeting stricter targets can generate surplus units for transfer, banking, or voluntary surrender. Deficits require the purchase of remedial units, with penalties ranging from $100–$380 per tonne CO₂eq depending on the compliance tier. Revenues will fund ZNZ fuel adoption, infrastructure, training, and support for vulnerable states.
Establishing uniform LCA standards is challenging due to the almost infinite variables in fuel production, transport, and use. Alignment with other regulatory schemes, such as FuelEU Maritime, also remains unclear.