Glosario del Reino Unido
Archivo original http://www.mmc.gov.uk/rep_pub/reports/2003/fulltext/480glossary.pdf.
1-in-20 peak day security
The requirement on Transco to plan its system to cope with an estimate
of the highest demand that is likely to be exceeded (whether on one or
more days) only in one year out of 20.
1-in-50 severe year demand An estimate of the highest demand that can be expected in one single
year in 50.
Accord Accord Energy Limited, a wholly-owned subsidiary of Centrica.
Associated gas Gas from a field producing predominantly oil and other liquids.
Bacton interconnector The interconnector for the transportation of gas from Bacton in
Norfolk to mainland Europe via Zeebrugge in Belgium, or vice versa.
Bar The unit of pressure that is approximately equal to atmospheric pressure
(0.987 standard atmospheres).
Beach gas Gas delivered to terminals on the Great Britain coast by producers.
Beach swing Variations in input from beach gas supplies.
Beach terminal A reception point for beach gas, where gas can be processed if
necessary and introduced into the NTS.
BG BG plc. Company created, along with Centrica, in the 1997 demerger
of British Gas plc.
BG Group BG Group plc. In 1999 BG changed its name to BG Group plc, which
demerged in 2000 when Transco became part of an independent group
called Lattice Group plc. The remainder of the former BG Group
retained that name. Lattice Group plc merged with National Grid Group
plc in 2002 to form NGT.
BG Storage BG Storage Limited. A subsidiary of BG Group which owned the
Rough and Hornsea storage sites and related assets and was sold to
Dynegy in 2001.
BGT British Gas Trading Limited, a wholly-owned subsidiary of Centrica.
British Gas The brand name used by Centrica in its UK retail gas supply operations.
British Gas plc The former privatized gas utility which demerged in 1997 to form BG
Cash-out Arrangements laid down in the Network Code under which individual
shippers are charged for any imbalance between their supply of gas to,
and demand for gas from, the transportation system on each gas day.
CCGT Combined cycle gas turbine. A type of generating plant in which
turbines, fuelled by natural gas (or an oil distillate) are used to drive
generators and the exhaust gases are passed through a boiler to produce
steam which drives an additional turbine coupled to a generator.
CEMG Centrica Energy Management Group, a business unit within Centrica.
Centrica Centrica plc or the whole Centrica group of companies, according to
Competition Act Competition Act 1998.
Constrained storage facility An LNG storage facility which provides support to the transportation
system and has been designated as constrained in the Network Code,
or subsequently in Transco.s annual Constrained Storage Statement.
Transco has the right to nominate flows of gas held there by shippers
(.constrain on.) when forecast demand downstream of a specified
constraint is higher than a declared trigger.
CSL Centrica Storage Limited, a wholly-owned subsidiary of Centrica. See
Cushion gas Gas that must remain in a storage facility to maintain sufficient pressure
for it to operate.
DGFT Director General of Fair Trading.
Diurnal storage Storage that responds to variation in demand or supply within the day.
Provided largely from gas holders and/or linepack.
DOPUL Dynegy Onshore Processing UK Limited.
Dry field A field producing predominantly gas (ie production of hydrocarbon
liquids is low).
DSL Dynegy Storage Limited, a subsidiary of Dynegy that owned the Rough
and Hornsea storage facilities (prior to the sale of Hornsea to SSE).
DSL was sold to Centrica and its name changed to CSL.
Dynegy Dynegy Inc. A US company which acquired BG Storage in 2001.
Energywatch The Gas and Electricity Consumer Council, established under the
Utilities Act 2000.
FSA Financial Services Authority.
FSMA Financial Services and Markets Act 2000.
FTA Fair Trading Act 1973.
Gas Act Gas Act 1986.
Gas holder A vessel used to store gas at low pressure for the purpose of providing
diurnal storage within an LDZ.
GWh Gigawatt hour. 1 GWh = 1,000 MWh.
HHI Herfindahl-Hirschman Index. A measure of industry concentration
calculated as the sum of the squares of the percentage market shares of
all suppliers in a given market.
HSE Health and Safety Executive.
I&C Industrial and commercial.
The electricity supplier which prior to 1998 acted as a monopoly
supplier of electricity to customers with a maximum demand of less
than 100 kW.
Interconnector A pipeline transporting gas from one transmission system to another.
A contract with an industrial or commercial customer that includes
terms entitling a supplier to interrupt supply of gas to that customer
either for its own purposes or in respect of Transco interruption rights
under the Network Code, which entitle Transco to interrupt supply to
a user of gas, for example where demand exceeds the capacity of any
part of the transportation system or when demand exceeds 85 per cent
of 1-in-20 peak day demand.
IPE International Petroleum Exchange.
IUK Interconnector (UK) Limited, the consortium of European energy companies
that owns and operates the Bacton interconnector.
kWh Kilowatt hour. A measure of an amount of energy.
LDS Local distribution system. LDS mains operate at low pressures, receive
gas from the LTS and deliver it to end-users.
LDZ Local distribution zone. An area supplied by one or more NTS offtakes.
Contains LTS and LDS pipelines.
Linepack The volume of gas within the NTS and LTS at any time. It can be
varied to provide diurnal storage.
LNG Liquefied natural gas: gas stored or transported in liquid form.
LTI contract Long-term interruptible supply contract.
LTS Local transmission system. The pipeline systems operating at pressures
about half those of the NTS that take gas from NTS offtakes and
transport it to end-users/consumers via downstream LDSs, and direct to
some larger users.
Morecambe The North Morecambe and South Morecambe gas fields in Morecambe
Bay owned by Centrica.
MWh Megawatt hour. 1 MWh = 1,000 kWh.
MRS Medium range storage.
NBP National balancing point. A notional point on Transco.s pipeline
system where gas can be traded between counterparties and their daily
imbalances are calculated.
Network Code The document defining the rights, responsibilities and obligations for
all users of Transco.s gas transportation system. It provides all system
users with equal access to transportation services. Other (much smaller)
gas transporters have their own network codes.
NGT National Grid Transco plc.
Nomination Notification by a shipper of the amount of gas it wishes to flow into or
out of the transportation system or other piece of gas infrastructure (for
example, interconnector, storage facility) or the amount of gas a
producer or shipper wishes to deliver/take under a contract.
NPV Net present value. The discounted present value of future cash flows.
NTS National transmission system. High-pressure system consisting of terminals,
compressor stations, other pipeline systems and offtakes.
Designed to operate at pressures up to 85 bar. NTS pipelines transport
gas from terminals to NTS offtakes.
NTS offtake An installation defining the boundary between the NTS and the LTS or
a very large consumer. The offtake installation may include equipment
for metering, pressure regulation etc.
OCM On-the-day commodity market. A screen-based service enabling
anonymous, financially cleared trading between market participants.
Ofgem The Office of Gas and Electricity Markets.
OFT The Office of Fair Trading.
Operating margins gas Gas stored for use by Transco to maintain system pressures under
circumstances, including periods immediately after a supply loss or
sharp change in demand, before other measures become effective, and
in the event of plant failure or the orderly rundown of the system.
OTO The Oil Taxation Office of the Inland Revenue.
Petroleum Act Petroleum Act 1998.
PPI Producer Prices Index. An index that measures the prices of industrial
Producer A company that extracts gas from an onshore or offshore field and
delivers it to a terminal.
SAP System average price. The price set by all Transco and shipper trades
on the OCM on a given day.
SBU Standard bundled unit of gas storage.
Shipper A company holding a shipper.s licence granted by Ofgem. Shippers
may buy gas from producers, sell it to suppliers and employ Transco
to transport it to suppliers. customers. A shipper may also be licensed
as a supplier.
SME Small and medium-size enterprise. Term used in this report to refer to a
non-domestic gas customer using less than 732,678 kWh (25,000
therms) a year.
SSC Storage services contract. A standard contract for the use of storage
capacity at Rough.
SSE Scottish and Southern Energy plc.
SSNIP Small but significant non-transitory increase in price.
STORIT CSL.s web-based information service, through which CSL receives
customer nominations, allocates capacity, supports secondary trading
and publishes information on Rough operations.
Supplier A company holding a supplier.s licence granted by Ofgem. Suppliers
contract with producers to buy gas that is then shipped through
Transco.s network (by a shipper) for supply to consumers. A supplier
may also be licensed as a shipper.
Top-up gas Gas which Transco has to put into store if it assesses that the amount of
storage capacity booked by shippers is inadequate to meet aggregate
demand under 1-in-20 peak day or 1-in-50 severe year conditions.
TPA Third-party access.
Transco Part of NGT. Owns and operates the primary natural gas transportation
system in Great Britain.
TWh Terawatt hour. 1 TWh = 1,000 GWh.
UKCS UK continental shelf.