Energy Term Glossary

Automatic Meter Read (AMR)

AMR is a system that provides automatic meter readings remotely. It uses technology used for telephones and is able to transfer this data into a billing system.

Availability also known as Kilovolt Amperes (KVA)

Availability (kVA) or Agreed Capacity refers to the limit of capacity for a site. For example if a site has an Availability of 200 kVA then maximum demand on that meter should not exceed that figure. It is set and charged by the local Distribution Network Operator (DNO). The kVA fee covers the maintenance costs of the network and can also be referred to as the Capacity Charge. Customers pay a fee per unit according to the agreed capacity for that site.

Carbon Reduction Commitment (CRC)

The CRC is a UK government emissions trading scheme for large organisations which are not eligible for EU Emissions Trading. This scheme is mandatory.

Climate Change Levy (CCL)

CCL is a government-imposed tax to encourage reduction in gas emissions and greater efficiency of energy used for business or non-domestic purposes. CCL is chargeable only on units/kWh used and not on any other component of the bill. The rate of CCL is index-linked and therefore will increase on 1 April each year.


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Data Collector (DC)

An organisation to carry out Data Collection for Half Hourly (HH) Metering Systems. The DC is appointed by the Suppliers to retrieve and validate metering data and forward it, to the Data Aggregator. The DC may be appointed by the customer but must always be accredited and contracted to the customer’s Supplier.

Deemed Contract

A contract which is deemed to apply when a customer begins a new supply at a property and has not signed a written contract for its supply. These contracts have a defaulted rate for supply until a customer requests a fixed price for a fixed period.

Distribution Network Operators (DNO)

Companies that are responsible for operating the networks that connect electricity consumers to the national transmission system and provide interconnection with embedded generation. There are 14 regional distributors who maintain the electrical network.

Distribution Use Of System Charges (DUOS)

These charges are published costs made by each Distribution Company for delivering electricity from the Grid Supply Point to the customer’s premises.

Estimated Annual Quantity (AQ)

This is the estimated annual consumption for your meters on a site. This is calculated by National Grid using historical data. Measured in kWh (electricity) or Therms (gas).

Fixed Charge

A daily, monthly or quarterly charge levied by the supplier and is in addition to the standing charge.

Fixed Term Contracts

Supply contract for a fixed price, over a fixed period of time which gives customers a constant price. Fixed Charges include Standing Charges and Availability Charges.

Gas Transporter (GT)

Responsible for maintaining a gas supply network. They may also be requested by the Supplier via the Shipper to provide a meter for the consumer’s usage.

Half Hourly Data

HHD is the product of the half-hour data meter. This data is made available to customers in the form of an excel spreadsheet.

Half Hourly Meters

Half Hourly meters are mandatory for all sites over 100 kva, and voluntary for sites under 100 kva. This meter sends your consumption data every half-hour to a central bank. The supplier will receive this information from the data collector.

Independent Public Gas Transporter (IGT)

An independent company who has responsibility of the maintenance of a gas supply network.

Kilowatt / Hour (kWh)

A unit or measure of electricity supply or consumption of 1,000 Watts over the period of one hour.

Letter of Authority

Authority required from the customer to enable Energy 4 You to obtain relevant contract information from a Supplier regarding your gas or electricity contract.

Meter Point Administration Number (MPAN)

Meter Point Administration Number or MPAN for short is a unique reference number used by the energy companies to identify your electricity connection to the national grid. It is sometimes called a supply number and is 21 digits long and can be found on your electricity bill.

Maximum Demand

Maximum Demand is the highest peak of usage (kWH) in any Half Hour during a calendar month or between two meter readings measured in either kW or kVA. This value is multiplied by 2 to give the MD on an hourly basis.

Meter Operator (MOp)

The organisation appointed to maintain metering equipment.

Meter Operator Charges (MOp Charges)

This charge covers the cost of maintaining metering equipment.

Meter Point Reference (MPR)

Meter Point Reference or MPR for short is a unique reference number used by the energy companies to identify your Gas connection to the National Grid. It is up to 10 digits long and can be found on your gas bill.

Meter Serial Number

The number stamped on the front of the meter. This changes when meter is exchanged.


Employs fewer than 10 full time equivalent people and has a turnover less than 2 million Euro’s or uses less than 200,000kWh’s of gas per year or 55,000 kWh of electricity per year.

National Grid

The National Grid owns the main transmission systems and is responsible for transmitting the electricity. All electricity generated in mainland UK is put into the National Grid before fed into distribution networks.

Non Half Hourly (NHH) Meters

Unlike HH meter a meter reader must visit the site to obtain readings.

Office of Gas and Electricity Markets (OFGEM)

OFGEM is the Office of Gas and Electricity Markets, regulating the gas and electricity industries in the UK. This is a statutory body representing the interests of gas and electricity consumers in the UK.

Pass Through Charges

Charges that appear on bills to cover the costs of third parties involved in the energy supply chain to deliver power.

Renewable Energy

Renewable energy’ is used to describe the energy produced using naturally replenishing resources. This includes solar power, wind, wave and tide and hydroelectricity. Wood, straw and waste are often called solid renewable energy, while landfill gas and sewerage gas can be described as gaseous renewables.

Renewable Obligation (RO)

This is the main government market mechanism to support renewable energy. It is an obligation on all electricity suppliers to supply a certain amount of their electricity sales from accredited renewable sources under the Climate Change Levy exemption scheme.

Smart Metering

The ability to remotely read non-half hourly (NHH) meters. Data is more reliable and more accurate bills are produced.

Standing Charge

Is a daily or monthly charge to contribute towards installation, maintenance and administration costs for the local Distribution Network Operator (DNO).


The term often used when a property owner installs a separate meter to monitor the consumption of a utility such as water, gas or electricity.

Supply Number

S-Number (also known as MPAN – Meter Point Administration Number). A unique number identifying the distribution company and the location of the metering point.

Take Or Pay

Your usage is estimated when you enter into an energy contract, if your usage falls by 20% or increases by 20% from your estimate your supplier may charge you a penalty fee for doing so.

Transmission Use of System (TUoS)

The charges are incurred for transmitting electricity across the National Grid network from the source of generation to the network of the local distribution company. The level of these charges is usually calculated by applying a rate charge to the TRIAD demand level.

Transportation Charge

A charge made by National Grid for the national transport of the shippers’ gas through the gas network (National and Regional Transmission system and the low and medium pressure distribution system) to the customer. The transportation charge consists of three elements, which are dependent on the locations of the particular terminal and offtake site: capacity charge; commodity charge; and site charge.

Unit Price

The price per unit of energy which includes 3 components only – energy wholesale price (energy at NBP), infrastructure costs and a cost to serve element


A unit used to measure the electromotive force of an electric current.