Glossary of terms used in the electricity sector

We provide definitions of all terms related to our business

Dictionary
Technical terms
  • A

    • ACCESS AND CONNECTION APPLICATION An official procedure whereby a user requests permission from the distributor to connect to the grid, either to consume or to feed energy into it.
      ACCESS CHARGESThis is the amount paid for the use of the transmission and distribution network. It is payable both when taking out a new supply contract and when requesting an increase in power.
      ACCESS TARIFF CONTRACT A legal agreement that allows a consumer to use the transmission and distribution networks to receive electricity at their supply point.
      ACTIVE ENERGYThe electricity you actually convert into light, heat, or motion; this is the main consumption figure shown on your bill.
      ACTIVE ENERGY METER A device that specifically measures the energy you consume and converts it into useful work (light, heat, etc.). This is the main data used for your bill.
      ACTIVE POWER This is the ‘useful’ energy, the energy that is actually converted into work (such as the light from a bulb or the rotation of a motor) and forms the basis of what we pay for.
      AMPERE (A)A unit measuring current intensity (the number of electrons passing through a point).
      APPARENT POWER This is the total sum of active and reactive power. It represents the total capacity that the grid must support for your equipment to function.

  • B

    • BILLING POWER This is the numerical value (in kW) used to calculate the fixed cost of your bill, based on your contracted power or the peaks recorded by the meter.
      BUSBAR SYSTEMA technical design used in electrical substations where all circuits are connected to a single common conductor (busbar). It is simple, but if the busbar fails, everything connected to it fails.

  • C

    • CHARGING POINTA specific installation designed to supply power to the batteries of electric vehicles
      CIRCUIT BREAKER A safety device (such as a fuse) designed to automatically cut off the flow of current when it exceeds a dangerous level.
      COMMISSIONING The final validation and activation process enabling a new installation to start receiving electricity.
      CONNECTION CHARGESThis is the overall term covering the payments the user must make to the distribution company so that the latter can carry out the necessary works and procedures to provide electricity to a new supply or to extend an existing one.
      CONNECTION TO THE GRIDThe technical and physical process of linking a property’s electrical installation to the utility company’s main electricity distribution network.
      CONSUMPTION The total amount of electricity you use over a given period of time. It is usually measured in kilowatt-hours (kWh).
      CONTRACT FEES This is the fee paid when signing a new supply contract or making changes to an existing one (such as changes in account holder or power rating).
      CONTRACTED POWER This is the maximum amount of energy you have agreed with your electricity supplier to use at any one time. It determines the fixed part of your bill.
      CUPS (UNIVERSAL SUPPLY POINT CODE)This is the ‘ID’ of your electrical installation. A unique alphanumeric code that unambiguously identifies your home or business.
      CURRENTThis is the flow or quantity of electrons circulating through a conductor at any given moment. It is measured in amperes.
      CUSTOMERS RECEIVING INSTALLATIONSThese are the end-use equipment and circuits that receive the energy to power the user’s appliances (light bulbs, electrical appliances, motors, etc.).

       

  • D

    • DIRECT METERING This is the standard metering system where the meter is connected directly to the grid. It is used in households and small businesses where the current is not excessively high.

  • E

    • EARTH LEAKAGE CIRCUIT BREAKER A safety device that trips automatically when it detects a current leak, protecting people from potential electric shocks or electrocution.
      ELECTRIC HOOK-UP CHARGESThis is the fee for the physical process of connecting your property to the distributor’s network. It is charged when you first connect to the electricity supply or when you change your power rating.
      ELECTRICAL INSTALLATION A set of circuits, cables, and devices responsible for receiving, transforming, and distributing electricity safely.
      ELECTRICAL RESISTANCEThis is the opposition or ‘braking’ effect that materials present to the flow of current. The higher the resistance, the more difficult it is for electricity to pass through (generating heat in the process).
      ELECTRICITY GENERATION INSTALLATION A technical system (such as solar panels or wind turbines) designed to produce electrical energy from various sources, either for self-consumption or for feeding into the grid.
      EON (OPERATIONAL ENERGISATION NOTIFICATION)A notification issued by the Distribution System Operator to the owner of a generation facility before the energisation of their internal network
      ESTIMATED CONSUMPTIONAn approximate calculation of electricity usage is made by the company when it is not possible to obtain an actual meter reading at that time.
      EXTENSION CHARGESThese are fees intended to cover the cost of the necessary network infrastructure (cables, poles, transformers) required to bring electricity to your supply point. They remain payable for several years if the contract is terminated.
      EXTENSION INSTALLATIONThis refers to the works or infrastructure required to extend the electricity network from the connection point on the existing distribution network to the location where the supply has been requested.

  • F

    • FON (FINAL OPERATIONAL NOTIFICATION) A notification issued by the Distribution System Operator to the owner of a generation facility, allowing them to operate the facility via the grid connection.

  • G

  • H

    • HIGH VOLTAGE (HV)Circuits with a voltage level exceeding 1,000 volts, used primarily to transmit large amounts of energy over long distances whilst minimising losses.
      HIGH VOLTAGE GRID  Large-scale infrastructure designed to transmit massive volumes of energy over very long distances with as little wastage as possible.
      HIGH VOLTAGE SUPPLY A contract for customers requiring very high power (such as large factories or trains) who receive their electricity directly from high-voltage lines.

  • I

    • INDIRECT METERINGThis is used when the current is so high that it would damage a standard meter. Intermediate transformers are installed to reduce the signal so that the metering equipment can record it safely.
      INSPECTION FEESThis is the cost of the technical inspection carried out by the distributor to check that your installation complies with current safety standards before providing the service.
      INSTALLATION (COMMISSIONING)This is the formal and technical process of connecting a facility to the electricity grid for the first time so that it begins to receive power, after verifying that it complies with all regulations.
      INSTALLED CAPACITYThis is the sum of the maximum capacities of all the appliances or generators that form part of a technical installation.
      INSTALLED CAPACITY OF A CONSUMPTION SYSTEM The maximum amount of power that all the electrical appliances and equipment in a home or premises could potentially consume if they were all switched on at the same time.
      INSTALLED CAPACITY OF A GENERATION FACILITYThe maximum production capacity of your energy sources (for example, the combined output of all your solar panels under optimal conditions).
      INTERNAL INSTALLATIONThis comprises all the cables, sockets, and control panels located within the customer’s property, from the meter inwards. Their maintenance is the responsibility of the owner.
      ION (INTERIM OPERATIONAL NOTIFICATION)A temporary permit allowing a generator to operate for a limited period to carry out operational tests before final authorisation. It is a notification issued by the Distribution System Operator to the owner of a generation facility, allowing them to operate using the grid connection for a limited period of time, as well as to commence compliance tests to ensure adherence to the relevant specifications and requirements.

  • J

  • K

    • KILOWATT-HOUR (kWh) The standard unit for billing total energy consumption over a given period.

  • L

    • LOAD CURVES A graphical representation or list of data showing how your energy demand varies throughout the day, helping you to understand your consumption habits.
      LOW VOLTAGE (LV)  This is the electricity that reaches our homes and small businesses, with a voltage safe for common domestic use (usually 230V).
      LOW VOLTAGE NETWORK The cabling we see on poles or building facades carries the final electricity (the electricity we use at home) through the air.
      LOW VOLTAGE SUPPLY The standard contract for homes and small businesses, where the electricity arrives already transformed for direct use.

  • M

    • MAIN CONTROL AND PROTECTION PANEL  This is the panel (usually located near the entrance to the property) that houses all the safety switches protecting your home’s internal circuits.
      MAIN FUSE BOX (CGP)A box containing the fuses that protect a building’s electrical installation against potential faults in the external power supply.
      MAIN CIRCUIT BREAKER (MCB)A safety switch located at the start of your fuse box that protects your entire home’s electrical installation against short circuits or excessive power demand that could damage the wiring.
      MAXIMETERA meter that does not merely total consumption, but records the highest power used at 15-minute intervals. It is essential for businesses that need to know their peak demand.
      MAXIMUM POWERThe highest energy value that a system can handle or has ever drawn over a period of time.
      MEDIUM VOLTAGEThis is the intermediate voltage level (usually between 1 kV and 36 kV). It is used to transmit electricity from substations to large industrial sites or transformer stations, which then step it down for supply to households.
      MEDIUM VOLTAGE NETWORKOverhead power lines that transport energy at intermediate voltages, connecting substations to local transformers.
      MEDIUM VOLTAGE UNDERGROUND NETWORKBuried cables operating at intermediate voltages, common in urban areas to supply transformer stations without visual impact.
      METERThe official device responsible for measuring and recording how much electricity flows from the grid to your property.
      MULTI-RATE METERA device capable of recording consumption during different time bands (e.g. peak, standard and off-peak) in order to apply different prices depending on the time of day.

  • N

    • NODE A physical point in the electricity grid where several lines or installations connect. It is like a ‘crossroads’ where energy is joined or distributed.

  • O

    • OVERLOAD Occurs when a cable or appliance is required to handle more energy than it can safely manage, causing it to overheat.
      OVERVOLTAGE A sudden and abnormal rise in voltage (for example, caused by lightning or a technical fault) which can burn out connected appliances if there are no protective measures in place.

  • P

    • POWER This is the capacity or rate at which a piece of equipment consumes or produces energy at a given moment. It is usually measured in watts (W) or kilowatts (kW).
      POWER CHARGE The fixed cost paid for the available connection capacity, regardless of whether you use a lot or a little electricity.
      POWER CONTROL SWITCH A safety mechanism (already built into new meters) that cuts off the power supply if you attempt to consume more power than you have contracted for.
      POWER DEMANDThis is the amount of energy your appliances are drawing from the grid at any given moment whilst they are switched on.
      POWER GENERATION MODULE Any piece of equipment or set of equipment that converts an energy source (wind, sun, gas) into electricity and is connected to the grid.
      PROTECTION SYSTEMA set of devices (such as relays or circuit breakers) responsible for detecting faults and disconnecting the affected section to prevent further damage to the grid or accidents.

  • Q

  • R

    • RATED POWER  The power at which a device has been designed by the manufacturer to operate continuously and safely.
      REACTIVE ENERGY A type of energy that is not consumed but flows through the grid, generated by certain appliances with motors or coils. If excessive, it may result in penalties.
      REACTIVE ENERGY METER A meter designed to record the energy that flows through the grid but is not consumed (generated by motors or coils), which may incur surcharges if it exceeds certain limits.
      REACTIVE POWER A type of energy required by certain devices (such as motors or transformers) to create magnetic fields. It does not generate direct work, but it "occupies" space on the grid and may incur surcharges if excessive.
      REFERENCE GRID MODELThis is a computational and theoretical tool used by regulatory bodies to calculate what an efficient electricity grid should look like and to determine the costs that should be recognised for distributors.
      RIGHT TO CONNECT TO A POINT ON THE GRIDThis is the technical and financial authorisation allowing a private installation to be connected to the general electricity infrastructure at a specific location.

  • S

    • SELF-CONSUMPTION A system where the user generates their own electricity (usually using solar panels) for direct use, reducing the amount purchased from the grid.
      SERVICE CONNECTION The section of the electricity network that connects the main street distribution network to the user’s supply point; it may be overhead or underground.
      SHORT CIRCUITAn accidental electrical fault that occurs when two conductors of opposite polarity come into direct contact, causing a sudden surge in current and a risk of damage or fire.
      SINGLE PHASEThis is the most common type of electrical installation in homes. It uses a single alternating current and two main cables (phase and neutral), which is sufficient for standard household appliances.
      SMART GRIDSNext-generation networks that use sensors and digital technology to automatically balance energy supply and demand, better integrating renewables.
      SMART METER (REMOTELY MANAGED)A modern digital device that records electricity consumption remotely, enabling accurate readings without the need for a technician to visit the property in person.
      SMART MICROGRIDSThese are small-scale energy systems that combine local generation (such as solar panels) with consumption. They can operate connected to the main grid or autonomously in the event of a power cut.
      SUBSTATIONSLarge facilities that step down the voltage of the electricity (from very high to medium, for example) and serve as hubs for controlling and distributing electricity across a region.
      SWITCHA basic mechanism that allows the flow of electrical current in a circuit to be turned on or off (such as the one we use to switch on a light).
      SYNCHRONOUS POWER GENERATION MODULE (SPGM) A specific type of generator that produces electricity in step (synchronised) with the frequency of the main electricity grid.

  • T

    • TARIFF METER Refers to the equipment configured to measure consumption under a specific pricing scheme contracted by the customer.
      TEMPORARY SUPPLY A type of temporary connection intended for specific events with a set end date, such as a fair, a circus, or a concert.
      TIME-OF-USE PRICING A tariff scheme in which the price of electricity varies depending on the time of day it is consumed. It divides the day into periods (peak, standard and off-peak) to encourage saving during hours of lower demand.

  • U

    • UNDERGROUND LOW VOLTAGE NETWORK The system of cables buried beneath the streets that distributes energy to buildings, being more aesthetically pleasing and better protected than the overhead system.

  • V

    • VOLT (V) The unit measuring electrical voltage or pressure. 

  • W

    • WATT (W) The unit measuring the power or rate at which energy is consumed.

  • X