36
LNG
INDUSTRY
MARCH
2016
require less than 50 million ft
3
/d of gas, floating
regasification is still a strong competitor to other solutions,
such as shore-based terminals and pipelines.
FSRUs provide safe, reliable and efficient service faster
and at a fraction of the cost of traditional LNG terminals,
particularly for small island markets where FSRUs can act as
a hub for small scale LNG deliveries. The old belief that the
Caribbean can not afford to invest in the infrastructure
needed to import natural gas is no longer applicable. A
potential solution for the Caribbean could be utilising an
FSRU, which acts as the central hub for LNG storage, a
loading point to small scale carriers using ship-to-ship (STS)
transfer technology, and enables the smaller LNG vessels to
distribute LNG to nearby consumption points. Small scale
LNG provides an effective solution for delivering
clean-burning natural gas to consumers who, due to either
geographic location or low demand, do not have access to
pipeline networks.
STS transfer
STS transfer may be conducted for routine commercial
reasons or in the case of an emergency. It occurs in the
open ocean, in a protected body of water at a location
between the LNG load port and the market delivery point,
or at a GasPort or Gateway terminal. During STS transfer,
a conventional LNG carrier moors alongside the FSRU and
transfers its cargo to the FSRU via hard arms across a jetty
located inside of a port or offshore environment, or by using
flexible cryogenic hoses. Cryogenic hoses allow flexibility
and remote access, which is especially helpful in spot
trading and emergencies.
One key prerequisite to the STS operation is metocean
conditions and parameters. For an STS transfer with the
vessels adrift, a location is chosen for the STS transfer,
which allows adequate room for the length of the operation.
Prior to mooring, the masters of the delivering LNG carrier
and the receiving FSRU establish communication via very
high frequency (VHF) radio and exchange key information via
email. The two vessels work with an LNG ship/shore
checklist developed by the Society of International Gas
Tanker and Terminal Operators (SIGTTO) that is adapted for
this particular operation. If the sea state is acceptable (i.e. if
the wave height and period are within agreed limits), the
final approach is made and the two vessels are moored
together. Mooring wires and Dyneema mooring lines
(jumper springs) are utilised to connect the two vessels
according to a specified pre-planned mooring arrangement.
Some FSRUs are fitted with quick release hooks (QRH)
replicating shore-side moorings where jumper springs are
not required.
In benign harbours throughout the Caribbean, or
wherever the metocean conditions permit, small LNG
volumes can be transferred between larger delivery vessels
to smaller LNG receiving vessels, thereby omitting the need
to utilise a terminal.
Conclusion
Floating storage and regasification for the region allows the
following:
A continuous supply of natural gas at the volumes
required.
LNG storage that is on the vessel as opposed to onshore
storage where the lack of portability may be a deterrent.
Reduced CAPEX.
The ability to bypass the need to use a small scale
terminal to capture LNG volumes.
Excelerate’s perspective on small scale LNG, and the
Caribbean in particular, is that the issue is primarily a
challenging logistical problem. The ability to utilise a handful
of assets to serve various islands in close proximity to each
other helps achieve the economics that projects need to
take off.
When it comes to the commodity itself, the company
believes that it can demonstrate a strong value proposition in
sourcing low priced LNG cargoes out of the global
marketplace and breaking them down (break-bulking), rather
than by entering into long-term contracts for supply at smaller
terminals. The LNG market has changed enormously over the
past months, making capturing cargoes outside of traditional
trade lanes even easier, and the ability to contract natural gas
at a competitive rate and on a short-term basis a reality.
Excelerate is actively developing marine assets for both
LNG transport and regasification that are
simple, economical, and with a minimal
maritime and environmental footprint,
with the primary objective to deliver
natural gas to the Caribbean islands.
LNG access can be provided to this
emerging market with uncomplicated,
scalable designs. Lastly, since a
significant amount of fuel consumed on
the Caribbean islands goes to the
transportation sector, the company is
not only engaged in delivering gas for
power generation, but to secondary
markets as well. This adds value by
connecting the dots between delivering
LNG for the power plants’ usage and
enabling bunkering projects and small
scale distribution for other industrial
users.
Figure 3.
Offshore ship-to-ship (STS) LNG transfer.
