Glossary
- SAF
Standard Address Format
- SBP
See System Buy Price
- SD
Settlement Day
- Seasonal Time of Day
Season time of day tariff or pricing. The price varies according to the time of day and the season of the year.
- SEL
Stable Export Limit
- Settlement
Is the mechanism by which how much electricity supplier’s customers have consumed and the wholesale payments that are due by the supplier for each half hour of each settlement day.
- Settlement Agents
The process by which suppliers and generators agree how much electricity was traded, the value of the trades and by whom.
- SFIC
System Fault Information Centre
- Shale Gas
Shale gas is an "unconventional" fossil fuel, which means that additional procedures are required to extract it beyond regular drilling. Many such unconventional sources of oil and gas were formerly too difficult (or uneconomic) to extract until recent advances in drilling technology. A combination of directional drilling and a process called hydraulic fracturing have made accessible large amounts of natural gas locked up in the tight pores of shale formations at depths of 2 km or more. Recent successes in the United States have driven prospecting across Europe. In 2010, Cuadrilla Resources Holdings Limited ("Cuadrilla") began drilling near Blackpool in the Bowland Shale (which runs from Preston to the Irish Sea).
According to the US Energy Information Administration (EIA), during the last decade, US shale gas production has increased fourteen-fold; it now accounts for 22% of gas production and 32% of total remaining recoverable gas resources in the US. By 2030, the EIA projected that shale gas would represent 14% of total global gas supplies.
- Short Position
A position that increases in values if the value of the underlying instrument or market price decreases in value.
- Short Term Operating Reserve
Short Term Operating Reserve (STOR)
A contracted Balancing Service, whereby the service provider delivers a contracted level of power when instructed by the System Operator, within pre-agreed parameters. The System Operator makes two kinds of payments for use of STOR, availability payments and utilisation payments.- SLC
Standard Licence Condition
- SME
Small and Medium Enterprises (SME) sector the SME sector includes a wide range of non-domestic consumers, from relatively large businesses for whom energy is a major cost to much smaller businesses that may closely resemble domestic consumers in their approach to energy procurement.
- SMP
System Marginal Price
- SMRA
Supplier Meter Registration Agent
- SMRS
Supplier Meter Registration Service
- SMRS
Supplier Meter Registration Service also known as MPAS.
- SO
System Operator
- SOIS
System Operator Incentive Scheme
- SoLR
Supplier of Last Resort
- Spark Spread
The spark spread represents the theoretical profit margin for a gas-fired power plant:
1. A positive spark spread implies that the wholesale price of electricity is higher than that of natural gas and that profit can therefore be made by burning gas for power;
2. A negative spark spread suggests that power is priced below the cost of natural gas and it is therefore not profitable to burn the fuel to produce electricity.
The spark spread can be expressed in £’s per megawatt hour (MWh) or £ per million British thermal units (mmBtu) or other applicable units. To express it in £/MWh, the spread is calculated by multiplying the price of gas, for example (in £/mmBtu), by the heat rate (in Btu/kilowatt hour), dividing by 1,000 and then subtracting the electricity price (in £/MWh). Also called a spark arbitrage.
- Spot Market
The market where energy commodities are traded in cash/physically and delivered immediately, not as futures.
- Spot Price
The price for the immediate delivery of a commodity.
- Spot Trading
Refers to trading for delivery on the same day as the trade (within day).
- Spread
The difference between the bid and ask price. Liquid markets are characterised by narrow bid/ask spreads.
- SSA
The Settlement System Administrator – is responsible for the operation of Stage 1 Settlement – the service is currently provided by ESIS.
- SSC
Standard Settlement Configuration
- SSD
Supply Start Date
- SSP
See System Sell Price
- Standard Settlement Configuration
SSC – each metering system is allocated to a Standard Settlement Configuration depending on the number and configuration of settlement registers for the metering system. Normally there is a one-to-one correspondence between the physical registers of a metering system and the settlement, or logical, registers associated with the SSC to which it is allocated.
SSCs distinguish between metering systems on the basis of the number of registers which record consumption and on the Time Pattern Regime (TPR) for each of these registers.
Each SSC has associated with it number of quantities called Measurement Requirements (MR). A MR refers to a value that represents an estimate of the annual rate of consumption recorded for the metering system populated on the relevant settlement register for the SSC.
- Stand-by-Supply
The amount of electricity required by a generator, e.g. for onsite use, when they are unable to generate due to plant failure.
- STC
System Operator Transmission Owner Code
- STOD
See Seasonal Time of Day
- STOR
See - Short Term Operating Reserve
- Structured Contracts
Where energy is purchased directly from generators or producers and are arranged bilaterally.
- STTEC
Short-term Transmission Entry Capacity
- SVA
Supplier Volume Allocation
- SVAA
Supplier Volume Allocation Agent
- SVA Metering System Number
A unique number relating to a metering point and which consists of the following:
- a 2 digit number determined by reference to the Licensed Distribution System Operator
- a 10 digit reference number provided by the relevant Licensed Distribution System Operator
- a 1 digit check number provided by the Licensed Distribution System Operator
- Swap
An agreement whereby a floating price is exchanged for a fixed price over a specified period. It is an off-balance-sheet financial arrangement involving no transfer of physical energy - both parties settle their contractual obligations by means of a transfer of cash. The agreement defines the volume, duration and fixed reference price.
Differences are settled in cash for specific periods - monthly, quarterly or six-monthly.
Swaps are also known as contracts for differences and fixed-for-floating contracts.
- Switched Load
Is a term used to describe metering arrangements where:
- The customer has a dedicated, separately metered circuit for the supply of electricity for heating purposes and this supply is switched by a contractor not under the control of the customer; or
- Electricity consumption taken during a period beginning after 21:00 GMT and ending before 09:00 GMT is separately metered by ‘Low’ register(s) (for low tariff) controlled by a time switch or teleswitch receiver device attached to the metering system.
- System Buy Price
The price paid in the Balancing Market by a party that requires more energy to meet its contractual commitments.
- System Margin
The difference between demand and supply. Otherwise referred to as the system being long or short.
- System Sell Price
The price paid in the Balancing Market by a party that has delivered more electricity than its consumers wanted to buy. Prices are often negative, meaning that a payment would need to be made to dispose of the unwanted electricity produced.