Business energy terms.
Without the fog machine.

A signed document giving a broker or consultant permission to act on a business's behalf with its energy supplier — requesting contract details, meter data, and pricing without the business needing to contact the supplier directly. An LOA does not authorise a broker to switch supplier or sign a contract; it only grants access to information, unless it explicitly states otherwise.

The rate a supplier charges when a business is consuming energy without a formal contract in place — typically because a previous contract has ended without renewal, or a business has moved into a new premises without agreeing terms. Deemed rates are almost always significantly higher than negotiated contract rates and are set unilaterally by the supplier.

Effectively interchangeable with a deemed rate in most contexts — the rate applied once a fixed-term contract expires and no new agreement has been signed. Businesses can end up here through late renewal, missed notice periods, or a change of occupier at a site.

A contract with no fixed end date that continues indefinitely until either party gives notice to terminate. Increasingly rare in commercial energy but still found in older agreements or certain flexible arrangements.

A contract where the unit rate and standing charge are locked in for the full contract term, regardless of how wholesale prices move. This gives budget certainty but means a business won't benefit if wholesale prices fall after the contract is signed.

A procurement strategy — typically used by larger consumers — where energy is bought in tranches over time rather than at a single fixed price, spreading exposure to wholesale market movements. Requires active management and is usually only cost-effective above a certain consumption threshold.

A contract restructuring option where a business partway through an existing fixed contract agrees a new blended rate that combines the remaining old contract with a new extended term — often used to smooth out a price spike or lock in a longer-term deal early.

A form of flexible purchasing where multiple customers' volumes are pooled together and bought as a single "basket" from the wholesale market, giving smaller businesses access to the kind of rates normally reserved for very large consumers.

The formal process of requesting competing quotes from multiple suppliers for a business's energy contract, usually run by a broker or TPI. A well-run tender compares like-for-like terms (contract length, standing charge, pass-through costs) rather than headline unit rate alone.

What happens when a fixed-term contract ends and, rather than moving to a deemed rate, it automatically renews — often at a much higher rate — because the customer didn't act within the supplier's notice window.

A clause within an energy contract stating that it will automatically renew for a further term unless the customer gives notice within a specified window (commonly 30–90 days before the end date). Missing this window is one of the most common ways businesses end up overpaying.

A short period — usually 14 days — after signing a new energy contract during which a business can cancel without penalty. This is a legal right for micro-businesses under Ofgem rules, though the exact terms can vary by supplier.

When a supplier bills a customer for energy used further back than the standard limit (Ofgem's back-billing rule caps this at 12 months for domestic and microbusiness customers) — often arising from a metering error, estimated readings, or an administrative delay.

The formal regulatory term for an energy broker or consultant who acts between a business and an energy supplier. Ofgem maintains a TPI Code of Practice, and reputable TPIs are typically registered and audited against it.

A company or individual who sources and negotiates energy contracts on behalf of businesses, earning commission from the supplier (built into the unit rate) rather than charging the client directly in most cases. See TPI above for the regulatory framing of the same role.

The formal transfer of an existing energy contract from one legal entity to another — for example when a business is sold, restructured, or changes its company name — without needing to negotiate an entirely new agreement.

The date on which a new energy contract officially begins supplying at the agreed rate. There is often a gap of weeks or months between signing a contract and its CSD, particularly when a business is locking in a future rate ahead of an existing contract's expiry.

The period during a supplier switch in which the outgoing supplier can raise an objection — commonly due to an unpaid balance, contract dispute, or mismatched contract end date — that pauses or blocks the transfer to a new supplier.

A unique 21-digit reference number identifying an individual electricity meter point in the UK, sometimes called a "supply number." It's used by suppliers, distributors, and brokers to identify exactly which meter a contract, bill, or query relates to.

The gas equivalent of an MPAN — a unique reference number identifying a specific gas meter point, used by the Gas Transporter and suppliers to track supply to that address.

A meter that records electricity consumption in 30-minute intervals throughout the day, giving suppliers and businesses granular visibility of usage patterns. Mandatory for larger consumers (typically above 100kW capacity) and increasingly common for smaller businesses as smart metering rolls out.

A meter that records total consumption but not the half-hourly breakdown — readings are typically taken periodically (monthly, quarterly) and consumption is estimated between reads using a standard profile. Common in smaller commercial premises.

A meter that automatically sends readings to the supplier at regular intervals, removing the need for manual or estimated reads. In the UK, business smart meters generally fall under the SMETS2 standard (see below).

The first generation of the UK's Smart Metering Equipment Technical Specification. Many SMETS1 meters lost some smart functionality when switching supplier and have since been migrated onto the shared SMETS2 network infrastructure.

The second-generation smart meter standard, designed so that smart functionality is retained even when a business switches supplier — unlike the earlier SMETS1 meters, which often reverted to "dumb" mode after a switch.

A metering system that automatically transmits consumption data to the supplier, similar in principle to smart metering but typically referring to older or dedicated commercial/industrial systems installed ahead of the smart meter rollout.

A classification (Profile Classes 1–8 in Great Britain) used to estimate a non-half-hourly meter's consumption pattern across the day, based on typical usage for that type of customer (e.g. domestic, small commercial, off-peak).

An "actual" reading is taken directly from the meter (manually, remotely, or via smart data); an "estimated" reading is calculated based on historical usage when no actual reading is available. Bills based on estimates are later reconciled once an actual reading is obtained.

A measure of the total electrical capacity available to a site, combining both the "useful" power (kW) and the reactive power the system also has to supply. A site's kVA capacity — agreed with the DNO — determines its maximum available supply and its capacity charge.

A measure of real, usable electrical power — the actual work being done, as opposed to kVA which includes reactive power. Business electricity bills are generally based on kWh (kilowatt-hours) consumed over time.

A charge levied by the DNO, based on the maximum kVA capacity a site has agreed to have available, regardless of how much of that capacity is actually used. Sites with capacity far exceeding their actual peak demand may be able to reduce this charge by having their agreed capacity lowered.

The organisation responsible for installing, maintaining, and servicing a half-hourly meter and its associated equipment. The MOP contract is typically separate from the energy supply contract itself and carries its own charges.

The organisation responsible for the ongoing management and data services of half-hourly metering equipment — often, but not always, the same company as the MOP.

The organisation that owns the physical metering asset itself, as distinct from the MOP (who maintains it) and the MAM (who manages the data). In practice these three roles are frequently, though not always, held by the same supplier or third party.

A code applied to a half-hourly electricity meter that accounts for the small amount of energy lost as electricity travels through the distribution network from the point of generation to the point of consumption. The LLF applied depends on the meter's voltage level and location, and it's used to adjust billed consumption to reflect these network losses — meters closer to generation (e.g. on the transmission network) typically have a lower loss factor than those further down the distribution chain.

A two- or three-digit code that defines which time-of-use structure applies to a meter — for example, whether it has a single flat rate, or separate day/night/weekend rates, and how many registers the meter uses to record them. The MTC tells a supplier exactly how to interpret and bill the readings coming off a particular meter.

The price energy suppliers pay to buy gas or electricity on the wholesale market, before any of the additional network charges, levies, and margin are added to arrive at the retail price a business actually pays.

The final price a business pays per unit of energy, made up of the wholesale price plus non-commodity costs (network charges, levies, supplier margin) and VAT.

A fixed daily charge applied regardless of how much energy is consumed, covering the fixed costs of supplying and metering a site. It's charged in addition to the unit rate, not instead of it.

The price charged per kWh (or per therm for some gas contracts) of energy consumed — the variable part of a bill that scales directly with usage.

A billing structure — common on meters with an appropriate MTC — where different unit rates apply depending on the time of day or day of week energy is consumed, typically to reflect cheaper off-peak wholesale pricing.

A historic UK transmission charging mechanism (being phased out under wider reforms) where a portion of a large consumer's annual network costs were based on their electricity usage during the three half-hour periods of highest national demand each winter. Businesses could reduce their Triad exposure by lowering demand during those windows.

Charges levied by the local electricity distributor (DNO) for the use of the local distribution network that brings electricity from the transmission grid to a business's premises. DUoS charges vary by time of day and region.

Charges levied for the use of the national high-voltage transmission network that moves electricity around the country. Historically linked to Triad periods, these charges are being reformed to a flatter, more predictable structure.

A charge covering the cost of balancing electricity supply and demand in real time across the national grid — historically variable by time of use, moving towards a fixed rate under ongoing charging reforms.

A UK government environmental tax added to business energy bills, charged per kWh of gas and electricity consumed. Certain energy-intensive industries and specific usage types can qualify for CCL exemptions or reduced rates via a Climate Change Agreement.

A now-closed-to-new-generation government scheme that required electricity suppliers to source a proportion of their supply from renewable sources, or pay a penalty — the cost of which was passed through to business energy bills as a non-commodity charge.

A scheme (closed to new applicants since 2019) that paid small-scale renewable generators for the electricity they produced and exported to the grid. The cost of legacy FiT payments is still recovered from all electricity bills as a non-commodity charge.

Non-commodity costs (network charges, levies, and other third-party costs) that a supplier passes directly on to the customer at cost, rather than fixing them within the headline unit rate — common in flexible and semi-flexible contracts.

A pricing structure where the supplier bundles all non-commodity costs into a single fixed unit rate for the full contract term, giving the customer complete price certainty but less transparency over how much of the rate is wholesale versus pass-through cost.

The collective term for everything added to the wholesale price to arrive at the final unit rate — network charges (DUoS/TNUoS/BSUoS), policy costs (CCL, RO, FiT), and supplier operating costs and margin. Non-commodity costs now make up a substantial and growing share of the total bill.

An Ofgem-mandated settlement reform that moved certain profile classes of business meter from estimated, profiled billing onto actual half-hourly settlement — meaning many smaller businesses now have their consumption billed and settled in the same granular way as larger HH sites.

A non-commodity charge that funds the Capacity Market, a mechanism ensuring enough electricity generation and demand-side capacity is available to keep the lights on during periods of peak demand.

A small non-commodity charge that funds a rebate scheme for electricity distribution in the North of Scotland, where distribution costs are disproportionately high due to geography.

An informal, umbrella term for the various government environmental and social policy costs added to energy bills — including RO, FiT, and CCL — reflecting the cost of funding renewable generation and energy efficiency schemes.

A voluntary agreement between energy-intensive businesses (in eligible sectors) and the UK government, allowing a reduced rate of Climate Change Levy in exchange for meeting agreed energy efficiency or emissions targets.

The Office of Gas and Electricity Markets — the UK government regulator for the gas and electricity markets, responsible for protecting consumers, licensing suppliers and networks, and overseeing the TPI Code of Practice that reputable brokers work under.

An independent, out-of-court process for resolving disputes between a business and its energy supplier or broker when a direct complaint hasn't been resolved. Ofgem requires suppliers and registered TPIs to belong to an approved ADR scheme.

A mandatory UK government scheme requiring large businesses (based on employee numbers, turnover, and balance sheet thresholds) to carry out energy audits every four years, identifying cost-effective energy-saving opportunities across buildings, transport, and industrial processes.

A UK reporting requirement obliging large companies to disclose their energy use and greenhouse gas emissions in their annual reports, intended to increase transparency and drive energy efficiency action at board level.

The regional company responsible for the physical electricity distribution network — cables, substations, and local infrastructure — that delivers electricity from the transmission grid to homes and businesses. DNOs charge DUoS fees for use of their network.

A DNO alternative that owns and operates the electricity distribution network for a specific site or development — often newer housing or commercial developments — rather than the regional incumbent DNO.

The company responsible for the physical pipeline network that moves gas from the national transmission system to individual premises within a region, equivalent in role to a DNO for electricity.

A GT alternative that owns and operates the gas pipeline network for a specific site or development, rather than the regional incumbent Gas Transporter.

A designation used in gas transportation charging that groups geographic areas by the cost of transporting gas to that location from the national transmission system — exit zone affects the transportation element of a gas bill's non-commodity costs.

Electricity generation (such as a solar farm or wind turbine) connected directly to the local distribution network rather than the national transmission system — this can affect DUoS charging for other users connected to the same part of the network.

The three distinct metering responsibilities on a half-hourly meter — Meter Operator (installs/maintains), Meter Asset Manager (manages data services), and Meter Asset Provider (owns the asset) — which may be held by one company or split across several, each carrying separate contractual charges.

An ADR scheme (referenced by its ADR Ref in TPI accreditation, such as Telnergy's E3561) specifically handling disputes between businesses, brokers, and suppliers relating to billing, contracts, and service issues.

A set of Ofgem-mandated safeguards ensuring suppliers identify and provide additional support to vulnerable customers — though these protections are primarily aimed at domestic and micro-business customers rather than larger commercial consumers.

When a business's supply is switched to a new supplier in error — without valid consent, or to the wrong meter point — triggering a formal Ofgem-governed process to reverse the transfer and return the customer to their original supplier and rates.

A state in which the greenhouse gas emissions a business or country produces are balanced by an equivalent amount removed from the atmosphere — through reduction, capture, or offsetting — resulting in no net addition to atmospheric carbon. The UK has a legally binding target to reach net zero by 2050.

The practice of compensating for greenhouse gas emissions produced in one place by funding an equivalent reduction or removal elsewhere — commonly through projects like reforestation, renewable energy development, or methane capture. Offsetting is generally considered a last resort after genuine emissions reduction, not a substitute for it.

A long-term contract in which a business agrees to buy electricity directly from a specific generator (often a renewable energy project) at an agreed price, rather than from a supplier's general pool. PPAs can provide price certainty and a verifiable renewable energy claim, but usually carry longer commitment terms than a standard supply contract.

A certificate proving that a given unit of electricity was generated from a renewable source, allowing suppliers to back "green" tariffs with evidence. Businesses on a REGO-backed tariff can claim their electricity is 100% renewable, though critics note REGOs don't guarantee the electricity used at any given moment was actually green.

The internationally recognised framework for categorising a business's greenhouse gas emissions: Scope 1 covers direct emissions from owned sources (e.g. company vehicles, on-site combustion); Scope 2 covers indirect emissions from purchased energy; Scope 3 covers all other indirect emissions across the value chain (supply chain, business travel, waste) and is typically the largest and hardest category to measure.

A rating (A to G) indicating a building's energy efficiency, required when a commercial property is built, sold, or let. Minimum EPC standards for let commercial property are tightening under UK regulation, with implications for landlords and tenants alike.

The process of reducing the amount of carbon dioxide (and other greenhouse gases) emitted by an organisation, sector, or economy — through measures such as switching to renewable energy, electrifying heat and transport, and improving efficiency.

The total greenhouse gas emissions caused directly and indirectly by an organisation, product, or activity, usually expressed in tonnes of CO2 equivalent (CO2e).

A Power Purchase Agreement specifically between a corporate energy buyer and a renewable generator, as distinct from utility-scale or government-backed PPAs — increasingly used by larger businesses to secure both price stability and verifiable renewable credentials.

An energy tariff marketed as supplying renewable electricity, typically backed by REGO certificates. The strength of the "green" claim varies significantly between suppliers depending on whether they also directly invest in renewable generation.

A general term for certificates (such as REGOs in the UK) that verify a given quantity of electricity was generated from a renewable source, used by suppliers and businesses to evidence green energy claims.

Certificates issued to accredited renewable generators under the (now closed to new entrants) Renewables Obligation scheme, which suppliers were obliged to acquire or pay a penalty for — the origin of the RO non-commodity charge still seen on bills today.

See also Regulatory & Compliance — a voluntary scheme letting eligible energy-intensive sectors access a reduced Climate Change Levy rate in return for meeting agreed efficiency or emissions targets, making it as much a sustainability lever as a compliance one.

An organisation that validates corporate emissions-reduction targets against the level of decarbonisation required to limit global warming in line with the Paris Agreement, giving businesses an externally verified benchmark for their net zero commitments.

The practice of a business adjusting its electricity consumption — reducing, shifting, or increasing it — in response to signals from the grid or a supplier, usually in exchange for payment. DSR helps balance the grid at times of peak demand or excess generation, and can generate a meaningful revenue stream for businesses with flexible loads.

On-site battery systems that store electricity — often generated on-site via solar, or bought cheaply during off-peak periods — for use later when demand or prices are higher. Increasingly paired with solar PPAs and DSR participation to maximise revenue from a single asset.

Electricity generation (such as rooftop solar or an on-site combined heat and power unit) located on the customer's side of the meter, used to offset consumption directly rather than being exported to the grid.

A Power Purchase Agreement specifically for solar-generated electricity, where a business hosts solar panels (often installed and owned by a third party) on its site and buys the electricity generated at an agreed rate, without the upfront capital cost of installing the system itself.

The infrastructure and energy management required to charge a business's electric vehicle fleet — encompassing charge point installation, load management to avoid excessive capacity charges, and often integration with off-peak tariffs or on-site generation.

A centralised system that monitors and controls a building's energy-using equipment (HVAC, lighting, metering) automatically, optimising consumption and enabling participation in demand-side response without manual intervention.

A form of grid balancing service where businesses with flexible assets (generation or demand) automatically adjust their output or consumption within seconds to help keep the national grid's frequency stable at 50Hz.

A grid balancing contract where businesses agree to reduce demand or increase on-site generation at short notice when National Grid ESO/NESO needs additional reserve capacity, in exchange for availability and utilisation payments.

The ongoing, real-time process of matching electricity supply and demand across the national grid, using mechanisms like frequency response, STOR, and the balancing mechanism to prevent instability or blackouts.

Any small-scale power generation or storage asset located close to where the electricity is used — solar panels, battery storage, or small-scale generators — as opposed to large, centralised power stations.

A localised group of electricity sources and loads that can operate connected to the main grid or independently ("islanded") from it, often used on large sites or campuses to improve resilience and enable local renewable generation.

Reducing electricity consumption during periods of highest demand (and therefore highest cost) — through battery discharge, generator use, or temporarily reducing non-essential load — to lower both energy costs and capacity charges.

Moving energy-intensive activities to off-peak periods when electricity is cheaper, rather than reducing overall consumption — for example, running industrial processes overnight rather than during the day.

The process by which a half-hourly meter's consumption data is used to calculate exactly what a business owes, based on actual usage in each 30-minute period rather than an estimated profile — see also P272, which extended this to smaller businesses.

A device attached to a meter that records consumption data at regular intervals for later retrieval or transmission, used particularly where full smart or AMR connectivity isn't in place.

Technology that allows a business's demand-side response participation to happen automatically — via a BMS or dedicated controller — without needing manual action each time a balancing signal is received.

The system National Grid ESO/NESO uses to balance electricity supply and demand in real time, buying and selling additional power from generators and large consumers in the final minutes before delivery when the market itself hasn't balanced perfectly.

A mechanism that pays generators and demand-side providers to guarantee they'll have capacity available during periods of peak demand, ensuring enough total capacity exists across the system to keep the lights on — funded via the capacity market charge on bills.

The organisation responsible for operating the electricity system across Great Britain in real time, balancing supply and demand second by second. Formerly National Grid Electricity System Operator (ESO), now the independent National Energy System Operator (NESO).

The 24-hour period the UK gas market operates on, running from 6am to 6am rather than midnight to midnight — a quirk that affects how gas trading, balancing, and billing periods are defined.

A daily average price for gas balancing, published by National Grid, used as a reference point for various gas market charges and settlement calculations.

A graph or dataset showing the current market price for energy to be delivered at various points in the future — used by buyers and brokers to assess whether current contract offers represent good value against where the market expects prices to move.

The practice of locking in a price for future energy delivery to protect against adverse price movements — the basis of fixed contracts, and central to how suppliers manage risk when offering fixed rates to customers.

The market in which energy suppliers, generators, and traders buy and sell gas and electricity in bulk, ahead of it being retailed on to end consumers — the foundation on which all retail energy pricing is built.

A wholesale trading market where electricity is bought and sold for delivery the following day, allowing suppliers and generators to fine-tune their positions closer to real-time demand.

Wholesale trading that happens on the same day as delivery, used to make final adjustments to a supplier's or generator's position as actual demand becomes clearer.

The wholesale electricity market mechanism where the price paid to all generators is set by the most expensive generation source needed to meet demand at that moment — often gas-fired plants — meaning even cheap renewable generation is paid the higher marginal rate.

A high-voltage cable connecting the British electricity grid to those of neighbouring countries, allowing electricity to be imported or exported depending on relative prices and availability — an increasingly important factor in wholesale price movements.

When a generator (often wind or solar) is instructed to reduce or stop output, typically because the grid or local network can't accommodate the electricity being produced at that moment — a growing issue as renewable generation capacity increases faster than network reinforcement.

The ranking of available generation sources from cheapest to most expensive, used by the system operator to decide which generators run to meet demand at any given time — renewables and nuclear typically sit at the bottom (cheapest), with gas peaking plants at the top.

The minimum, continuous level of electricity demand on the grid (or at a single site) that persists around the clock, as opposed to the additional, variable demand that fluctuates through the day.

The maximum level of electricity demand experienced during a given period — for the grid, typically early evening in winter; for an individual business, whenever its operations draw the most power.

The standard unit of energy consumption used for billing — one kilowatt of power used for one hour. This is the figure multiplied by the unit rate to calculate the variable portion of an energy bill.

Equal to 1,000 kWh — the unit typically used when discussing consumption or generation at a larger, industrial, or grid-wide scale rather than for a single site's bill.

A traditional unit of heat energy still referenced in some UK gas billing and historical contracts, equal to approximately 29.3 kWh. Modern gas bills are calculated in kWh, converted from the volume of gas measured (in cubic metres or feet) using the calorific value.

A measure of the energy content of a specific batch of gas, published daily by the Gas Transporter, used to convert the volume of gas recorded on a meter into kWh for billing purposes. Calorific value varies slightly depending on the source and composition of the gas.

The recorded volume of gas passed through a meter, taken in cubic metres or cubic feet depending on the meter type, and converted to kWh using the calorific value for billing.

The recorded amount of electricity consumed, taken directly in kWh (or, on older meters, converted from a dial or digital display reading).

A cap on the rates domestic energy suppliers can charge customers on default tariffs, reviewed quarterly by Ofgem. It does not apply to business energy contracts, which are unregulated in terms of pricing — a key distinction business customers need to understand when comparing their situation to domestic news coverage.

Business (non-domestic) energy contracts differ from domestic ones in several important ways: no Ofgem price cap, generally longer fixed terms, different consumer protection rules (full protections mainly apply to micro-businesses), and bespoke rather than published tariffs.

The practice of managing energy contracts, consumption, and compliance across multiple business premises under a single strategy — often consolidating contract end dates, standardising suppliers, and centralising reporting for efficiency.

A systematic review of a business's energy use, identifying where and how energy is consumed and where savings could be made — mandatory for large businesses under ESOS, but valuable for organisations of any size.

Software or a combined software-and-hardware system used to monitor, control, and optimise a business's energy consumption across its sites and equipment.

The pattern of a site's energy use across a day, week, or year — used by suppliers to estimate non-half-hourly consumption and by businesses to identify opportunities for load shifting or peak shaving.

An estimate of a gas site's total annual consumption, calculated from historical usage and used by suppliers to set billing and by the Gas Transporter to determine transportation charges — broadly the gas equivalent of an electricity site's estimated annual consumption.

A measure of how consistently a site uses electricity relative to its maximum demand, expressed as a percentage — a high load factor means fairly constant usage, while a low load factor indicates sharp peaks and troughs.

A measure of how efficiently a site uses the electricity it draws, comparing real power (kW) to apparent power (kVA). A poor power factor means a site is drawing more capacity from the network than it productively uses, which can result in reactive power charges.

A charge applied when a site's power factor falls below an agreed threshold, reflecting the additional strain a poor power factor places on the network — often reducible through the installation of power factor correction equipment.

Both are unique meter identification numbers, but MPAN identifies an electricity meter point while MPRN identifies a gas meter point. A dual-fuel business site will have both, and they're never interchangeable — quoting the wrong one to a supplier will pull up the wrong meter's data entirely.

kW measures real, usable power — the actual work being done. kVA measures apparent power, which includes both real power and reactive power. A site's agreed capacity with its DNO is set in kVA, because the network has to be able to supply the full apparent power even though only the kW portion does useful work.

These terms describe the same role from two different angles: TPI (Third Party Intermediary) is the formal regulatory term Ofgem uses, while "energy broker" is the everyday commercial term. A reputable broker will describe itself as an Ofgem-registered TPI as a mark of accountability.

A half-hourly (HH) meter records consumption in 30-minute intervals, giving granular, near-real-time data. A non-half-hourly (NHH) meter records only periodic total readings, with consumption between reads estimated using a profile class. HH metering is mandatory above certain capacity thresholds but is becoming more common at smaller sites too, partly driven by reforms like P272.

A DNO (Distribution Network Operator) is the regional incumbent responsible for most of the UK's electricity distribution network. An IDNO (Independent DNO) owns and operates the network for specific sites or developments — often newer builds — operating under the same regulatory framework but as a distinct, smaller-scale operator.

The gas equivalent of the DNO/IDNO distinction: a GT (Gas Transporter) is the regional incumbent pipeline operator, while an iGT (Independent Gas Transporter) owns and operates the gas network for specific developments or sites.

The wholesale price is what a supplier pays to buy gas or electricity on the market. The retail price is what a business actually pays, after non-commodity costs (network charges, levies, supplier margin) and VAT are added on top. The gap between the two has grown significantly as non-commodity costs have risen.

A fixed contract locks in a single unit rate for the full term, providing certainty but no benefit if wholesale prices fall. A flexible contract buys energy in tranches over time, tracking the market more closely — offering potential upside but requiring active management and generally only suiting larger consumers.

The standing charge is a fixed daily cost regardless of consumption, covering fixed supply costs. The unit rate is the variable cost per kWh consumed. Together they make up the two components of every energy bill — a low unit rate with a high standing charge can end up more expensive than the reverse for a low-usage site, and vice versa.

Three distinct roles around a half-hourly meter: the Meter Operator (MOP) installs and maintains the physical meter; the Meter Asset Manager (MAM) manages its data services; the Meter Asset Provider (MAP) owns the metering asset itself. These roles can be held by one company or split across several, each carrying its own contract and charges.

Both are renewable energy certificates, but they serve different purposes. ROCs (Renewables Obligation Certificates) were issued to generators under the now-closed Renewables Obligation scheme, forming the basis of a specific non-commodity charge. REGOs (Renewable Energy Guarantees of Origin) are the certificates currently used to evidence that a unit of electricity came from a renewable source, underpinning today's green tariffs.

Scope 1 covers a business's direct emissions (its own vehicles, on-site combustion). Scope 2 covers indirect emissions from the energy it buys. Scope 3 covers everything else across its value chain — supply chain, business travel, waste, and beyond — and is usually the largest, hardest-to-measure category by far.

"Carbon neutral" typically means emissions have been balanced out, often largely through offsetting, with no requirement to have reduced them first. "Net zero" is a more rigorous standard, generally requiring genuine, substantial emissions reduction first, with offsetting used only for the small residual that can't practically be eliminated.

A PPA (Power Purchase Agreement) is a direct, long-term contract with a specific renewable generator, often providing a verifiable, traceable source of green electricity. A green tariff is a standard supply contract from a regular supplier, backed by REGO certificates — a simpler option but a less direct link between the electricity bought and the renewable generation it represents.

DUoS charges cover the use of the local distribution network bringing electricity to a business's premises. TNUoS charges cover the use of the national high-voltage transmission network that moves electricity around the country. Both are non-commodity charges, but they fund entirely different parts of the network.

AQ (Annual Quantity) is the gas-side estimate of a site's total annual consumption. EAC (Estimated Annual Consumption) is the equivalent figure used on the electricity side. Both serve the same underlying purpose — estimating yearly usage for billing and charging purposes — but apply to different fuels and different parts of the supply chain.

Baseload is the constant, minimum level of demand that persists around the clock. Peak load is the highest level of demand reached during a given period. The gap between the two — and how a business or the grid manages it — has a major bearing on both cost and infrastructure planning.

The Capacity Market pays for capacity to exist and be available, ensuring enough total generation and demand-side resource is in place ahead of time. The Balancing Mechanism is the real-time process of actually using that (and other) capacity to keep supply and demand matched minute by minute. One is about having enough; the other is about using it correctly, right now.