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transported with the NGH technology. This is a considerable volume penalty (and hence transport
cost) if considered in isolation, with the cheaper ships for hydrate transport the process could be
economic.
The gas-to-solids option for transporting and storing stranded gas to market has been extensively
researched and laboratory tested for more than a decade. BG Group, Marathon, NTNU (Norway),
and others have worked on a range of gas-to-solids transportation technologies (Fischer, 2001) and
have taken them to small-scale pilot plants. The concepts include storage and transport of gas either
as atmospheric hydrates or as a paste in pressurized insulated containers or as frozen hydrates
mixed with refrigerated crude oil for atmospheric pressure transport. Even though these studies
have proved the concept of storing natural gas in hydrates technically feasible, applications have
not progressed beyond the laboratory stage because of complexities of the process, slow hydrate
formation rates, and costs. No projects are close to commercialization, but technological advances
continue to be made, e.g., forming the hydrates from a surfactant solution (Rogers et al., 2005) that
may make this possible in the long-term.

1.10.6. Gas-to-Wire

Currently, much of the transported gas destination is fuel for electricity generation. Electricity
generation at or near the reservoir source and transportation by cable to the destination(s) (gas-to-
wire) are possible. Thus, for instance, offshore or isolated gas could be used to fuel an offshore
power plant (may be sited in less hostile waters), which would generate electricity for sale onshore
or to other offshore customers.
High voltage direct current (HVDC) transmission lines offer the most technically viable solution

to moving large quantities of electric power over large distances (up to about 1500 km) keeping
line losses less than 10%. However, HVDC is capital intensive and requires costly converter stations
at either end of the transmission line. Additional costs for installing and then operating and
maintaining gas turbines at the remote site would be incurred.
While HVDC cables are now being used more widely to transport electricity tens of kilometers no
projects to develop remote gas fields in this way have yet been sanctioned. Distance, cost, and
efficiency of remote generation make other options currently more attractive. There are other
practical considerations to note such as if the gas is an associated gas, then if there is a generator
shutdown and no other gas outlet, the whole oil production facility might also have to be shut
down, or the gas released to flare. Also, if there are operational problems within the generation

plant the generators must be able to shut down quickly (in around 60 s) to keep a small incident
from escalating. Additionally, the shutdown system itself must be safe so that any plant that has
complicated processes that requires a purge cycle or a cool-down cycle before it can shut down is
clearly unsuitable (Ballard, 1965). Finally, if the plant cannot shut down easily and/or be able to
start up again quickly (perhaps in an hour), operators will be hesitant to ever shutdown the process,
for fear of financial retribution from the power distributors.

1.10.7. Comparison Between Various Methods
As discussed previously, there are a number of options of exporting natural gas energy from oil and
gas fields to market. However, distance to market and potential production volumes (dependent on
the reserves size of the gas resource) influence the technologies that might viably be used to exploit
remote gas fields (see Fig. 1.11).
Any gas energy export route requires a huge investment in infrastructure, and long-term “fail

proof” contracts, covering perhaps 20 years or more. However, improvements in technology,
economies of scale, and synergies will undoubtedly lower capital costs and further improve the
project economics over the next few years. Most of these technologies have reached a stage where
commercialization on a wide scale is only a few years away. However, their use carries risks in
terms of technology, credit worthiness, revenue security, and market competition risks, each of
which needs to be appropriately mitigated.
Gas is currently transported to markets primarily via two long-established methods (pipeline and
LNG technology). Alternative technologies, which have been refined and developed in recent years,

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