Third IMO Greenhouse Gas Study 2014

102 Third IMO GHG Study 2014
Year
Table 39 – Annual emissions of refrigerants from the global fleet
and estimated shares of different refrigerants
Refrigerant emissions,
tons, reefer TEU excluded
Low bound, tons High bound, tons %, R-22 %, R134a %, R404
2007 8,185 5,926 10,444 80% 17% 4%
2008 8,349 6,045 10,654 77% 19% 4%
2009 8,484 6,144 10,825 75% 21% 4%
2010 8,709 6,307 11,110 73% 23% 4%
2011 8,235 5,967 10,503 71% 24% 4%
2012 8,412 5,967 10,726 70% 26% 4%
UNEP 2010 7,850
Non-exhaust emissions of NMVOCs from ships
The reported global crude oil transport in 2012 was 1,929 million tons (UNCTAD Review of Maritime Transport
2013). This study applies the same methodology as the Second IMO GHG Study 2009 and uses the net
standard volume (= NSV at bill of lading - NSV at out-turn) loss of 0.177%. This corresponds to 0.124% mass
loss and results in VOC emissions of 2.4 million tons, which is very close to the value of the 2009 study figures
for 2006 (crude oil transport 1,941 million tons, VOC emissions 2.4 million tons).
2.2 Bottom-up other relevant substances emissions calculation method
2.2.1 Method
Three primary emission sources are found on ships: main engine(s), auxiliary engines and boilers. The
consortium studied emissions from main and auxiliary engines as well as boilers in this report. Emissions from
other energy-consuming sources were omitted because of their small overall contribution. Emissions from
non-combustion sources, such as HFCs, are estimated consistent with the Second IMO GHG Study 2009
methods.
2.2.2 Main engine(s)
Emissions from the main engine(s) or propulsion engine(s) (both in terms of magnitude and emissions factor)
vary as a function of main engine rated power output, load factor and the engine build year. The main engine
power output and load factor vary over time as a result of a ship’s operation and activity specifics: operational
mode (e.g. at berth, anchoring, manoeuvring), speed, loading condition, weather, etc. Emissions are also
specific to a ship, as individual ships have varying machinery and activity specifications. The bottom-up
model described in Section 1.2 calculates these specifics (main engine power output and load factor) for each
individual ship in the global fleet and for activity over the year disaggregated to an hourly basis. This same
model is therefore used for the calculations of the other main engine emissions substances.
2.2.3 Auxiliary engines
Emissions from auxiliary engines (both in terms of magnitude and emissions factor) vary as a function of
auxiliary power demand (typically changing by vessel operation mode), auxiliary engine rated power output,
load factor and the engine build year. Technical and operational data about auxiliary engines are often missing
from commercial databases, especially for older ships (constructed before 2000). Technical data (power rating,
stroke, model number, etc.) for auxiliary engines of new vessels can be found much more frequently than for
those of old vessels; however, these form a very small percentage of the entire fleet. There are typically two or
more auxiliary engines on a ship and the number and power rating (not necessarily the same for all engines on
a ship) of each engine is determined by the ship owner’s design criteria. This means that the actual operation
of the specific auxiliary engines, by vessel type and operational mode, can vary significantly from ship to
ship. There are no commercial databases that provide these operational profiles on the basis of operational
mode or vessel class. This lack of data will hinder the determination of auxiliary engine power estimation
using predetermined auxiliary engine load levels. For this reason, the approach taken in this study is based
on the vessel surveys conducted by Starcrest for various ports in North America. These surveys allow the
determination of auxiliary engine power requirements or total auxiliary loads in various operating modes of