2020 mandatory initiative is not the only factor relevant to the phenomenon of clean
mobility of ships. Indeed, CO 2 emission which is a major culprit in terms of
generation of GHG is a matter of equally serious concern. The correlation between
GHG emissions and LNG usage as marine fuel is therefore quite significant.
The findings of a new study on use of LNG as marine fuel indicate that LNG
bunkering provides a small reduction or even an increase in GHG emissions in
comparison with heavy oil fuel which is the prevailing norm. At any rate, this
depends on various factors including engine design. In the worst-case scenario,
LNG fuel may produce life cycle emissions that exceed those from the use of
heavy oil but can, on the other hand, result in reductions of CO 2 emissions by
30%. Utilization of LNG involves other emission sources which can reduce the net
benefit. In certain instances, methane which is a powerful GHG more so than CO 2 ,
may generate higher GHG emissions than vessels fuelled by heavy oil. The study
referred to concludes that reaching the IMO GHG reduction target of 50% by 2050
may not be feasible by using improvements in efficiency and LNG alone; rather, an
improvement rate of 35% is more likely achievable. Given various other advantages
of LNG use including the low emissions of NOx, SOx and PM may on the whole
render the LNG option relatively attractive in the medium term.
34
It is somewhat alarming that methane emissions from ships using LNG as fuel are
higher than those produced by marine fuel oils currently in use. There is also the
issue of unburned methane emissions known as methane slip, which is significant.
Researchers have commented that in order to retain benefits accruing from LNG
usage in terms of GHG, the question of methane emissions must be addressed. Thus,
there are issues relating to LNG which require further investigation and these matters
are being addressed by expert bodies including the IMO, the European Sustainable
Shipping Forum and the Society for Gas as a Marine Fuel.
35
Needless to say, a robust legal regime relating to GHG implications of LNG
should be articulated particularly in respect of its regulatory control.
5 Concluding Remarks
The legal regimes governing shipboard LNG is to some extent patchy and, as
explained above, there is a notable lacuna in the private law domain with the
emerging use of LNG as a marine fuel. However, this may not be an immediate
concern to the international maritime community as a wide use of LNG as a marine
fuel is not envisaged. Specifically, the feasibility factor of ships using LNG as fuel is
very much dependant on its availability, which in turn depends on the existence of
LNG bunkering infrastructure on a global basis. In other words, whereas the use of
LNG as an alternative marine fuel is desirable, the demand for its use and the supply
34 See Maritime Executive (2019); see also Sharafian et al. (2019).
35 See European Commission (2016).
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J. Xu and P. K. Mukherjee
mobility of ships. Indeed, CO 2 emission which is a major culprit in terms of
generation of GHG is a matter of equally serious concern. The correlation between
GHG emissions and LNG usage as marine fuel is therefore quite significant.
The findings of a new study on use of LNG as marine fuel indicate that LNG
bunkering provides a small reduction or even an increase in GHG emissions in
comparison with heavy oil fuel which is the prevailing norm. At any rate, this
depends on various factors including engine design. In the worst-case scenario,
LNG fuel may produce life cycle emissions that exceed those from the use of
heavy oil but can, on the other hand, result in reductions of CO 2 emissions by
30%. Utilization of LNG involves other emission sources which can reduce the net
benefit. In certain instances, methane which is a powerful GHG more so than CO 2 ,
may generate higher GHG emissions than vessels fuelled by heavy oil. The study
referred to concludes that reaching the IMO GHG reduction target of 50% by 2050
may not be feasible by using improvements in efficiency and LNG alone; rather, an
improvement rate of 35% is more likely achievable. Given various other advantages
of LNG use including the low emissions of NOx, SOx and PM may on the whole
render the LNG option relatively attractive in the medium term.
34
It is somewhat alarming that methane emissions from ships using LNG as fuel are
higher than those produced by marine fuel oils currently in use. There is also the
issue of unburned methane emissions known as methane slip, which is significant.
Researchers have commented that in order to retain benefits accruing from LNG
usage in terms of GHG, the question of methane emissions must be addressed. Thus,
there are issues relating to LNG which require further investigation and these matters
are being addressed by expert bodies including the IMO, the European Sustainable
Shipping Forum and the Society for Gas as a Marine Fuel.
35
Needless to say, a robust legal regime relating to GHG implications of LNG
should be articulated particularly in respect of its regulatory control.
5 Concluding Remarks
The legal regimes governing shipboard LNG is to some extent patchy and, as
explained above, there is a notable lacuna in the private law domain with the
emerging use of LNG as a marine fuel. However, this may not be an immediate
concern to the international maritime community as a wide use of LNG as a marine
fuel is not envisaged. Specifically, the feasibility factor of ships using LNG as fuel is
very much dependant on its availability, which in turn depends on the existence of
LNG bunkering infrastructure on a global basis. In other words, whereas the use of
LNG as an alternative marine fuel is desirable, the demand for its use and the supply
34 See Maritime Executive (2019); see also Sharafian et al. (2019).
35 See European Commission (2016).
700
J. Xu and P. K. Mukherjee