Third IMO Greenhouse Gas Study 2014

Inventories of emissions of GHGs and other relevant substances 99
Fishing vessels and reefer ships
In Table 36, two distinctions between the existing reports (UNEP, DG ENV) are made. First, the refrigerant
charge carried by the world fishing fleet (“Miscellaneous – fishing”) was based on the DG ENV report, which
describes the use of refrigerants on board the European fishing fleet. In this study, the weighted average
(number of vessels, refrigerant charge carried) of the European fishing fleet (approximately 8,000 vessels) was
used to estimate the air conditioning and cooling needs of the global fishing fleet. The composition of the
EU fishing fleet is likely to be different from the global fleet, and this will be reflected in the estimates of the
refrigerant emissions of the global fishing fleet. The second difference concerns reefer ships. According to both
existing reports (UNEP, DG ENV), the reefer fleet carries 1 ton–5 tons of refrigerants per ship for cargo cooling.
This study takes the average (2.5 tons of refrigerants) and assumes R-22 to be used in vessels built before 2000
(DG ENV, 2007).
Reefer containers
Refrigerants can also be found in the cooling systems of reefer containers, which are used to provide a controlled
environment for perishable goods, like fruit, during cargo transport. The fleet of dedicated refrigerated cargocarrying
vessels has decreased over the years and is slowly being replaced by container ships carrying reefer
containers. According to the DG ENV report (2007), each reefer container carries 6 kg refrigerant charge, of
which 15% is lost annually. The number of refrigerated containers has been estimated in the DG ENV report
(2006 figure) as 1.6 million TEU. In this study the number of refrigerated containers for 2012 was based on
the projected number of reefer plugs of the world container fleet (1.7 million TEU). The reefer container count
was based on the IHS Fairplay data for 5,400 container ships (1.7 million TEU). The projection has some
inherent uncertainty, because reefer plug installations (rather than reefer TEU counts) have been used. Also,
the completeness of the container ship fleet in the data set used to determine the reefer plug count is likely to
have some impact on the reefer TEU numbers, because this data set consists of some 85,000 vessels and so
does not cover the complete global fleet.
Estimated emissions of refrigerants from ships
Both the UNEP and DG ENV reports use the 100 gt limit to indicate a vessel that has refrigerants on board.
This assumption was based on expert judgements on vessels that operate in a variety of climate conditions
and need air conditioning.
In this study, the fleet-wide assessment is made according to the vessel construction year (before 2000,
constructed that year or later) and refrigerant type is assigned on the basis of the vessels’ age. For old vessels,
HCFCs (R-22) were assumed, while new vessels use HFCs (R134a/R404a).
The estimated annual total of refrigerant loss in the global fleet in 2012 is described in Table 37.