SEA LNG has expressed the opinion that analysis presented by ICCT in its recently published study: Fugitive and unburned Methane Emissions from Ships (FUMES), while innovative, suffers from a range of significant methodological limitations.
According to SEA-LNG, the FUMES study highlights emissions challenges that have long been known and that are being actively addressed by the maritime industry and equipment manufacturers of all types. They are also the focus of a range of initiatives including the Methane Abatement in Maritime Innovation Initiative (MAMII) and the EU-funded GREEN RAY project.
The limitations of the ICCT study call into question its relevance as an input into regulatory development, specifically the determination of emissions factors used in IMO and EU regulations, SEA LNG notes. They include:
- The use of an experimental airborne measurement methodology which is not verified against industry standards, nor calibrated against on board measurements.
- The fact that the analysis is based on a limited number of vessels, using older low-pressure engine technologies, in particular low-pressure 4-stroke engines. There are very few measurements from the high-pressure dual fuel technologies which have virtually eliminated methane slip and which account for more than half the LNG-fueled vessels in the new build order book.
- The inability to distinguish between individual onboard emissions sources which makes it impossible to quantify levels of methane slip associated with specific engine technologies.
- Measurements were focused on atypical vessel operating conditions and engine load factors. The study focuses on exhaust emissions from ships during port stays and manoeuvring in and out of ports, representing less than 10% of ships’ operational conditions. Related to this, the majority of observations were taken with engine loads of around 0-30%. Main engines are designed to run at loads of between 60% and 100%, the range at which they operate for the majority of voyage time. At these loads, engines show the lowest levels of methane slip.
As regards regulation, it is SEA-LNG’s view that the emissions factors used in EU and IMO regulations should be based on certified operational measurements of the exhaust gas emissions from different propulsion and auxiliary engine technologies. Regulations should also allow these emission factors to be updated as engine manufacturers continue to improve the emissions performance of their new engines and technology providers develop methane abatement technologies which can be retrofitted to existing engines.
We encourage ongoing research, innovation, and collaborations, such as MAMII, within the maritime industry to develop and implement more sustainable LNG-fuel solutions. SEA-LNG welcomes constructive dialogue and collaboration with all stakeholders to achieve our shared environmental goals.
… said SEA LNG in their statement
