The Global
Natural Gas Market
Natural gas is the cleanest burning of any fossil fuel.
It has therefore become a global fuel of choice. High demand for hydrocarbons
in established markets like the United States and in emerging markets
like India and China, have significantly increased the global demand
for natural gas.
The global
consumption of natural gas is projected to grow by 70% over the 25 year
period running from 2001 to 2025. At 2.2% growth per annum, the natural
gas sector will far outstrip the annual growth of the oil or coal sector.
By 2025, 150 TCF of natural gas will be consumed annually.
Sustained
high prices for natural gas and strong demand the world over has prompted
a boom in the development of numerous multi-billion dollar LNG projects.
LNG is stored as a liquid at -165 C but at virtually no pressure. The
regasification of LNG into usage compressed natural gas (CNG) for distribution
to consumers requires heating and compression. This requires a costly
regasification facility. In addition, environmental and safety concerns
make it a challenge to site such facilities anywhere near populated
areas in the world, especially in the United States.
Due to
globally increasing demand of natural gas, and the economic limitations
of LNG transporting natural gas, CNG has re-emerged as a viable transport
option.
What is Compressed Natural Gas (CNG)?
Natural gas is often associated with oil as both are
commonly found together in the same reservoir. Non-associated natural
gas is gas that is found without oil.
CNG is
compressed natural gas stored at pressure. It consists primarily of
methane (85-95%), with trailing amounts of ethane, propane, and butanes,
usually ranging between 100 similar to the way it naturally exists in
the Earth's crust. The higher the pressure, the more gas that can be
contained in a unit of space. Refrigerating compressed natural gas further
increases the net volume of gas in a given space. Refrigerating CNG
to -30C can increase the density by more than 50% from ambient temperature.
Why Stranded Gas is a Problem and CNG is the Answer
Approximately one-third (1/3) of the world's discovered
natural gas is considered stranded. Stranded natural gas is that which
is beyond the economical limit of a pipeline or capital-intensive LNG
project. Of the world's stranded gas, over half lies in offshore locations,
ideal for CNG transportation by ship.
There are
several large reserves in the world that would justify an LNG project,
however, due to political risk factors, these same reserves are also
considered stranded. In such cases, CNG may transport this stranded
natural gas, avoiding the necessity of expensive land-based LNG facilities.
As CNG
carriers do not require a regasification facility near populated markets,
natural gas from Trans Ocean Gas carriers can be offloaded through an
offshore mooring buoy and transported to shore through a sub-sea pipeline.
Using a turret mooring buoy, CNG carriers can offload miles away from
populated areas. The loading of CNG can be performed using offshore
mooring buoys as well. There are several submerged loading buoys currently
operating in the world today, potentially providing Trans Ocean Gas
with access to many existing natural gas markets all over the world.
By using
a submerged mooring buoy outside of territorial waters (12 miles), CNG
can be delivered virtually anywhere. Public safety will not be a concern
when the ship is beyond the horizon.
FRP:
The Optimal Solution for CNG by Ship
Trans Ocean Gas is the only CNG proponent in the world
that will use fibre reinforced plastic (FRP) pressure vessels to transport
CNG by ship.
FRP pressure
vessels have been proven safe and reliable through critical applications
in aerospace, in national defense, in the offshore oil and gas industry,
and most importantly in public transit.
The use
of FRP pressure vessels overcomes all the deficiencies of proposed steel-based
methods. The Trans Ocean Gas method using FRP pressure vessels is:
- Light
weight (1/3 that of steel);
- Corrosion
resistant (thermoplastic liner);
- Safe
from rupture (leak before burst characteristic);
- Highly
reliable (probability of failure <10e-5);
- Resistant
to ultra-low temperatures (-60C); and
- Very
cost effective (one-third that of comparable steel-based systems).
The Trans
Ocean Gas CNG containment system is fabricated in modular cassettes
for ease of installation and hook-up. The cassette system holds numerous
FRP bottles vertically, with connecting manifolds on both the top and
bottom of each cassette. The vertical mounting allows for the removal
of condensed natural gas liquids at any point during a voyage or on
station. The designed steel cassette frames also help to isolate the
gas containment system from hydro-dynamic movements and vibrations.
The cassette system also allows for 100 percent visual inspection, while
in service. To ensure continuity of the corrosion resistant FRP pressure
vessels, the manifolds and piping network up to the first isolation
valve are fabricated using low-temperature stainless steel.
Trans Ocean
Gas intends to manufacture its FRP containment systems in house. Trans
Ocean Gas will license and lease its CNG systems to gas owners and entities
that wish to transport bulk CNG. This will allow many countries and
gas owners to economically transport their stranded natural gas reserves
to new and existing locations for economic growth, development, and
profit. Relatively little infrastructure will be required to gain access
to this new source of energy through the Trans Ocean Gas CNG solution.
New or
existing ships may be used to transport CNG using the Trans Ocean Gas
method. High-speed voluminous container ship hull forms will make the
most efficient FRP CNG carriers. Existing ships converted into FRP CNG
carriers will have good short-term economics (e.g., for projects with
a 10 year lifecycle). However, for CNG projects with longer lease terms,
new ships may prove to be more cost effective.
Trans Ocean
Gas is also developing a barge-oriented solution for the Gulf of Mexico
and other areas of the world that have relatively benign marine environments.
Such FRP-CNG barges may contain 100 mmscf.
New Market Creation
Many new markets will result from the flexibility of
the Trans Ocean Gas method. There are hundreds of potential new markets
for CNG transportation that do not compete with pipelines or LNG. Through
the Trans Ocean Gas CNG methods, Island nations and remote populations
will for the first time gain access to natural gas for power generation
and for economic development. Due to its many islands and dense population,
Asia is poised to be a major benefactor from the safe and economical
transportation of CNG by ship and by barge.
FRP Verification Testing
A joint industry project to verify and certify the Trans
Ocean Gas CNG method was sanctioned on July 21, 2005. Prototype testing
is currently ongoing. Full certification by DNV is anticipated in the
second quarter of 2008.
For certification,
DNV will witness the testing of the Trans Ocean Gas CNG method. As an
international classification society, DNV is committed to the safety
of life, property and the environment. DNV is recognized as one of the
world's leading organizations in research and development of innovative
technologies for the offshore and maritime industries.
Commercialization Path of TOG CNG Transportation
Once FRP bottles have been certified for CNG transportation
by ship, Trans Ocean Gas will manufacture and lease its FRP systems
for CNG projects around the world. Several potential gas transportation
projects are awaiting certification for sanction.
Trans Ocean
Gas will also qualify its FRP gas containment systems for use in 40ft
inter-modal refrigerated containers (reefer boxes) and tractor trailers.
A reefer box will hold approximately 500 Mscf where as a fifth-wheel
trailer will contain approximately 900 Mscf. A fully loaded reefer box
will weigh approximately 30 metric tons. The reefer boxes will have
the same dimensions and corner locks as standard 40ft ISO modal containers.
Technical
Background Information
FRP pressure vessels are manufactured using a plastic
liner as the mandrel on a computer controlled filament-winding machine.
As the mandrel is spun, a continuous filament of glass fibre is drawn
through an epoxy bath then wound onto the mandrel in a helical formation.
It is the filament windings that provide the strength of an FRP pressure
vessel. When cured, the filament windings are held in place by an epoxy
matrix. A stainless steel port boss at each end allows the FRP bottles
to be connected to upper and lower piping manifolds within each cassette.
The port bosses are connected directly to the plastic liners before
the filament fibre is wound on.
As detailed
on the Competitive Advantages of FRP for CNG
Transportation page, the resulting FRP pressure vessel provides
significant technical and competitive advantages to Trans Ocean Gas.
