In recent years, the International Maritime Organization (IMO) has strongly committed to climate change mitigation and the reduction of atmospheric emissions. Air polluting ship emissions are regulated by MARPOL Annex VI:
Regulation 13 establishes NOx emission limits for engines with a power output of more than 130 kW and introduces a Tier approach:
Tier II is globally applicable to all ships built since 1 January 2011 Tier III is applicable to Yachts of more than 24 m in load line length, larger than 500 GT, built after 1 January 2016, and operated inside the North American or United States Caribbean Sea Emission Control Areas (ECAs). Tier III will also become applicable to Yachts constructed after 1 January 2021 even below 500 GT, when operated inside the Baltic Sea or the North Sea ECAs. Tier III compliance requires the installation of catalytic mufflers (SCR) and the use of urea solutions (Adblue); this is quite bulky equipment that needs to be installed near the engines, thus requiring larger engine rooms.
As a consequence, the living quarters, the “payload” of a yacht, suffer a consequential contraction; yards and manufacturers are struggling to organise this equipment in the most space-efficient way, but it seems inevitable that there will be an impact.
Regulation 14 sets sulphur content limits on any fuel oil used on board. Already from 1 January 2015, ships operating inside ECAs are required to use fuel oil with a sulphur content of 0.1% or lower. However, from 1 January 2020, ships operating outside ECAs will also be required to use low sulphur fuel oil (max 0.50 % content), unless fitted with an approved Exhaust Gas Cleaning System(Scrubber). The fuels with a sulphur content of 0.50% or lower are reported to be chemically very different from the present ones, and therefore the switch to a new fuel needs to be carefully managed to address the compatibility of the new fuel with the one already present on board: investigation may be needed into the compatibility of the new fuel with existing machinery, and attention must be given to fuel viscosity and low temperature properties, since new fuels may require fuel heating equipment if used in cold climates.
From 1 March 2020, it will be prohibited to carry non-compliant fuel on board (except those ships fitted with scrubbers), in order to facilitate enforcement.
Furthermore, IMO has committed itself via a “strategy on reduction of GHG emissions from ships” to reduce CO2 emissions from ships by 50% by 2050 compared to those in 2008. No concrete steps to reach this objective have been made so far, but expectations are high for the next Marine Environmental Protection Committee meeting in 2020, when specific proposals are expected to be presented by Member States.
Carlo Aiachini, Giovanna Carosi