Putting a meaningful price on maritime emissions could accelerate the switch to lower-GHG fuels without creating the consumer shock many fear, according to Andy Lane of CTI Consultancy in a Splash247 analysis published this week.
Warmest July on record sets the context
BBC News reported this week that the world's oceans experienced their warmest July on record, according to the EU's Copernicus Climate Change Service. The average sea-surface temperature between 60°N and 60°S was 20.96°C. Separately, the global average surface temperature in July was 1.47°C above the estimated pre-industrial level. Lane noted that atmospheric CO₂ has risen from approximately 280 parts per million (ppm) before industrialisation to more than 420 ppm today, with the increase overwhelmingly attributable to human activities.
Shipping's share of global emissions
Globally, transport accounts for roughly 15% of total greenhouse-gas emissions, according to UN estimates. Within transport, shipping contributes around 11%, although the precise percentage varies depending on whether the scope is all shipping or international shipping, CO₂ alone or all greenhouse gases, and which year and accounting methodology is used. On a tonne-kilometre basis, shipping is extraordinarily efficient compared with most other forms of freight transport, Lane wrote. Even eliminating shipping's emissions completely would make only a relatively modest contribution to global emissions, but every sector has to contribute to the effort.
26 years of IMO measures
The IMO's first resolution specifically addressing CO₂ emissions from ships dates back to 1997. The first IMO greenhouse-gas study followed in 2000, with further major studies in 2009, 2014 and 2020. Measures adopted since then include the Energy Efficiency Design Index (EEDI) and SEEMP, mandatory fuel-consumption data collection, the 2018 Initial GHG Strategy, and EEXI and CII. From the first IMO resolution in 1997 to the implementation of EEXI/CII in 2023, 26 years elapsed between the first formal IMO CO₂ resolution and the first major mandatory measures aimed at existing ships' energy efficiency and operational carbon intensity. Lane wrote that there is a reasonable argument that this was not fast enough.
EEXI compliance and engine power limitation
EEXI is essentially a technical efficiency requirement for existing ships. One relatively straightforward compliance route is to install an Engine Power Limitation (EPL) or Shaft Power Limitation system, which restricts the maximum power available to the propulsion system. That can reduce a vessel's maximum speed capability, but slow-steaming was already standard, with ships sailing at 70–75% of their limits. Lane posed what he described as the more interesting question of whether EEXI is being strongly enforced in practice.
What this means for freight operators
For forwarders and shippers, the core argument in the Splash247 piece is that the cost of cleaner shipping may be smaller than many fear. The article contends that pricing maritime emissions could speed the adoption of lower-GHG fuels without triggering consumer shock, a scenario that would reshape fuel-cost calculations across ocean supply chains.
| Key figures from the analysis | Value |
|---|---|
| Average sea-surface temperature (60°N–60°S), July | 20.96°C |
| Global average surface temperature anomaly, July | 1.47°C above pre-industrial |
| Atmospheric CO₂, pre-industrial / today | ~280 ppm / >420 ppm |
| Transport share of global GHG emissions | ~15% |
| Shipping share of transport emissions | ~11% (UN estimate) |
| Vessel operating speed as share of limits | 70–75% |
| IMO first CO₂ resolution to EEXI/CII implementation | 1997–2023 (26 years) |
Watch list
- Whether EEXI is being strongly enforced in practice, flagged by Lane as the key open question.
- Whether a meaningful price on maritime emissions gains traction as a mechanism to accelerate the shift to lower-GHG fuels, the central argument of the Splash247 analysis.
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