Future electricity supply is the responsibility of the
Electricity Supply Industry Planning Council (ESIPC). For further information refer to the
web site http://www.esipc.sa.gov.au
At the national level the National Electricity Market
Management Company (NEMMCO) is responsible for determining the adequacy of future supply,
and maintains a reserve margin of generating capacity above predicted demand. Each year
NEMMCO publishes supply scenarios for the national market in the Statement of
Opportunities. For further information visit the NEMMCO web site at http://www.nemmco.com.au
The greater part of the States demand for natural gas
is sourced from the Cooper Basin in the far north-east of the State and extending into
south-west Queensland. This gas is processed through the plant at Moomba and transported
through the Moomba to Adelaide pipeline system (MAPS). A failure in operations in the
fields, the plant or the pipeline could have a serious impact on the operations of the
State. However, with the construction of a second pipeline from Western Victoria (See
below) supply security will be enhanced.
Approximately one-third of the States demand for
electricity is supplied from gas-fired generators. Any disruption in the flow of gas may
also impact on electricity supplies.
An interruption to the supply of raw gas to the Moomba
Plant through a field problem is unlikely to impact on the supply of gas to the State. The
Producers will be able to bring on additional fields or withdraw gas from storage to meet
Failure within the Moomba Gas Processing Plant could
severely impact on the supply of gas to the State, depending on the location and nature of
the failure. The ability of the Plant Operators to withdraw gas from underground storage
at Moomba and deliver that gas to MAPS without passing the gas through the Plant provides
some delivery of gas and lessens the impact on the SA market. Raw gas from the Big Lake
field is of such composition that it may be directly mingled with gas from storage, thus
increasing the quantity of gas available to the market. The Plant operators are currently
increasing the quantity of gas stored at Moomba as a contingency plan against plant or
When full of gas, MAPS contains sufficient gas to supply
the SA market for 1 2 days, provided those industrial customers with interruptible
contracts for supply stop using gas and other industries, where possible, revert to
alternate fuels. Torrens Island Power Station (TIPS) is able to burn fuel oil, for a
limited time, in place of natural gas to relieve the pressure on the demand for gas. Where
a short term failure to the gas supply occurs upstream of the (MAPS) transmission line,
gas supply can continue to be delivered to the markets with little disruption.
Where a disruption occurs in the transportation of the gas
(ie. Through MAPS), Epic Energy can quickly isolate the relevant part of the pipeline to
initiate repairs. Repairs to the pipeline can generally be undertaken with minimal
disruption to the overall supply of gas. Interruption to supply to
"interruptible" consumers where possible and the use of alternate fuels will
again minimise the impact of the disruption on the gas consumers.
Origin Energy Asset Management Limited (OEAM), operators of
the distribution systems downstream of MAPS, are able to isolate sections of the system in
which a failure occurs. This localises the impact on the consumers.
In consultation with the gas industry, the Energy SA has
developed administrative procedures to be used to address a shortfall in the supply of gas
to end-users. The authority to ration available gas is provided under the Gas Act 1997.
The Minister has the authority to direct certain consumers not to use gas and to issue a
direction as to the quality of gas suitable for distribution. The procedures ensure the
safe disconnection, and subsequent reconnection, of consumers and that essential services
continue to have access to natural gas for as long as possible.
As indicated above, restricting gas to end-users cannot be
made in isolation of the need for electricity generation. Arrangements are in place to
ensure that any assessment of gas load shedding is based on the prevailing energy market
conditions at the time with a view to achieve the best possible outcome for the good of
The current Gas Sales Agreements to which the Government is
party with the Cooper Basin Producers expire at the end of 2005. Each of Origin Energy and
Terra Gas Trader have their own separate agreements with the SA Producers for a quantity
of gas for a period extending beyond 2005. However, current indications are that further
sources of gas must be identified and agreements in place by around 2005/06 to satisfy the
forecasted demand. Several options are identified below.
The proposed Papua New Guinea to Gladstone (Qld) gas
pipeline, the already commenced Gippsland to Sydney pipeline and the options of connecting
Mt Isa to the Alice Springs to Darwin pipeline or the Mereenie (Northern Territory) fields
to Moomba provide suitable sources of gas to the State. Additional gas from the south-west
Queensland Cooper Basin is also a viable source for future supplies.
SEA Gas Pty Ltd and TXU have commenced the construction of
a 680 kilometer underground natural gas pipeline between Port Campbell, Victoria and
Pelican Point, South Australia. SEA Gas is a consortium including Origin Energy (owner of
the Quarantine power station) and International Power (owner of Pelican Point power
station). TXU is the owner of the Torrens Island power stations. The $500 million project
will provide an alternative source of natural gas to the Moomba-Adelaide pipeline, and
have a potential capacity of 125 petajoules. The pipeline is due for completion in early
2004. The security of supply and competition resulting from the two sources of supply
should assist competitive pricing of electricity in the medium term.