A
- #AMR meter
- An automated meter reading meter. It sends readings remotely, so bills are based on actual rather than estimated reads.
- #AQ (Annual Quantity)
- The estimated annual gas consumption for a meter, used to price contracts and set take or pay limits.
- #Availability (kVA)
- Also called Agreed Supply Capacity (ASC). The capacity reserved for your site on the electricity network. You pay for it whether you use it or not, and pay excess capacity charges if you go over it.
B
- #Back billing
- A bill for energy used in the past that was not billed at the time. Under Ofgem rules, suppliers cannot bill microbusinesses for energy used more than 12 months earlier where the supplier was at fault. Billing disputes and back bills
- #Baseload
- The steady minimum electricity a site uses at all times, including out of hours.
- #BICS
- The British Industrial Competitiveness Scheme, which exempts eligible manufacturers from some electricity policy costs from 2027. BICS explained
- #Bill validation
- An ongoing service that checks every energy and water invoice against your contract and meter data, queries errors with the supplier and chases credits. Bill validation
- #BSUoS (Balancing Services Use of System)
- Charges that recover the cost of balancing the electricity system second by second. Since April 2023 they are charged to electricity users only, as a fixed tariff set in advance.
C
- #Capacity Market
- A policy cost on electricity bills that pays generators and other providers to be available at times of peak demand.
- #CCA (Climate Change Agreement)
- A voluntary agreement for energy intensive sectors that gives a discount on the Climate Change Levy in return for meeting energy efficiency targets. Compliance and schemes
- #CCL (Climate Change Levy)
- A tax on business energy use, with reliefs for eligible activities and Climate Change Agreements.
- #CfD (Contracts for Difference)
- A government scheme supporting low carbon generation, recovered through a levy on electricity bills.
- #Change of tenancy (CoT)
- Telling the supplier that a business has moved into or out of a property. Until a new contract is agreed, the new occupier is usually charged deemed rates. Billing disputes and back bills
- #Contract health check
- A free, one off look at a recent bill to check where your current contract stands: rates, end date, reliefs and anything worth querying. Contract health check
D
- #DC/DA
- Data Collector and Data Aggregator, the agents who retrieve and process half hourly meter data for settlement. Metering, MOP and DC/DA
- #Deadlock letter
- A written final response to a complaint, after which the customer can refer the matter to the Energy Ombudsman.
- #Deemed rates
- The rates a supplier charges when you use energy at a property without a contract in place, for example after moving in. They are usually much higher than contracted rates.
- #DNO (Distribution Network Operator)
- The company that owns and runs the local electricity network in your area. Great Britain has 14 distribution areas.
- #DUoS
- Distribution Use of System charges, paid to the local network operator for delivering electricity to your site.
E
- #EAC (Estimated Annual Consumption)
- The industry's estimate of how much electricity a non half hourly meter uses in a year, used for settlement and for pricing contracts.
- #Energy Ombudsman
- The free, independent scheme that resolves complaints between energy suppliers and eligible customers, usually after eight weeks or once a deadlock letter has been issued.
- #ESOS
- The Energy Savings Opportunity Scheme, a mandatory energy audit every four years for large undertakings. Compliance and schemes
- #Estimated read
- A meter reading the supplier has calculated rather than taken. Bills based on estimates can drift a long way from actual use.
- #Export
- Electricity generated on site and sold back to the grid or to another user.
F
- #Feed in Tariff (FiT)
- A scheme that paid small scale generators for the electricity they produced. It closed to new applicants in 2019, but its costs are still recovered through electricity bills.
- #Fixed price contract
- A contract where unit rates are locked for the full term in one purchase. Fixed or flexible?
- #Flexible contract
- A contract where volume is bought in tranches over time, billed at the weighted average price. Risk managed buying
- #Forward curve
- The prices at which future delivery periods are trading today.
G
H
- #Half hourly (HH) metering
- Metering that records consumption every 30 minutes, required for larger sites and used for settlement. Metering, MOP and DC/DA
K
- #kWh and MWh
- Kilowatt hour and megawatt hour, the units in which energy is bought. 1 MWh is 1,000 kWh.
L
- #LOA (Letter of Authority)
- A signed authority allowing a consultant to obtain information and quotes on a client's behalf.
M
- #MHHS (Market wide Half Hourly Settlement)
- An industry programme moving every electricity meter in Great Britain onto half hourly settlement, so usage is settled on actual half hourly data.
- #Microbusiness
- Ofgem's term for a small business customer: broadly one with fewer than 10 employees and turnover or balance sheet of no more than 2 million euros, or one that uses no more than 100,000 kWh of electricity or 293,000 kWh of gas a year. Microbusinesses have extra protections.
- #MOP (Meter Operator)
- The party contracted to install, maintain and certify a half hourly meter. Metering, MOP and DC/DA
- #MPAN and MPRN
- The unique reference numbers for an electricity supply point (MPAN) and a gas supply point (MPRN).
N
- #Net zero
- Reducing greenhouse gas emissions as far as possible and balancing what remains, so that overall emissions are zero.
- #Non commodity costs
- Everything on an energy bill other than the wholesale energy itself: network, policy and supplier costs.
- #Notice period
- The window in which you must tell your supplier you are leaving at the end of a contract. Miss it and some contracts roll over automatically.
O
P
- #P272
- The change that moved larger sites onto half hourly settlement.
- #Pass through contract
- A contract where some non commodity costs, such as network or policy charges, are passed on at actual cost rather than fixed in the price.
- #Peer to peer (P2P) energy
- Buying electricity directly from named renewable generators, matched half hourly to your consumption through a licensed supplier, with any shortfall topped up from the grid. Also called direct renewable supply. Peer to peer and direct renewable supply
- #PPA (Power Purchase Agreement)
- A long term contract to buy power directly from a generator, or for a generator to sell its output.
- #Profile class
- A number from 00 to 08 at the start of the top line of an electricity supply number. 00 means half hourly; 01 to 08 describe how a non half hourly meter is assumed to use energy.
R
- #Reactive power charges
- Charges on some half hourly supplies when equipment draws power that does no useful work, usually a sign of poor power factor.
- #Reduced rate VAT
- VAT at 5% instead of 20%, which applies where business use is small (on average up to 33 kWh of electricity or 145 kWh of gas a day) or where at least 60% of the supply is for a qualifying use. Five common bill errors
- #REGO
- Renewable Energy Guarantees of Origin, certificates evidencing that electricity was generated from renewable sources.
- #Renewables Obligation (RO)
- A policy cost on electricity bills that funds renewable generators accredited under the scheme. It closed to new generation in 2017, but its costs continue.
- #Rollover contract
- A contract that renews automatically, often at higher rates, if notice is not given in time.
S
- #Scope 1, 2 and 3 emissions
- The standard way of grouping a business's greenhouse gas emissions: direct emissions (Scope 1), purchased energy (Scope 2) and the wider value chain (Scope 3).
- #SECR
- Streamlined Energy and Carbon Reporting, which requires qualifying companies to report energy use and emissions in their annual accounts. Compliance and schemes
- #SEG (Smart Export Guarantee)
- A requirement on larger suppliers to offer a tariff that pays small generators, up to 5 MW, for the electricity they export to the grid.
- #SPID (Supply Point ID)
- The reference number for a business water or wastewater supply point in England's water market. Water procurement
- #Standing charge
- A fixed daily charge on a supply, regardless of consumption.
T
- #Take or pay
- A contract term requiring a minimum volume to be paid for whether used or not.
- #TNUoS
- Transmission Network Use of System charges, paid for use of the national transmission network. TNUoS and HV sites
- #TPI (Third Party Intermediary)
- The regulator's term for energy brokers and consultants. How we are paid
- #Trade effluent
- Business wastewater other than ordinary sewage and surface water. It needs consent from the water company and is charged separately.
U
- #Unit rate
- The price per kWh of energy used, shown in pence on your bill.
V
- #Volume tolerance
- The band, usually a percentage either side of your expected usage, within which a contract allows consumption to vary. Using more or less than the band can bring extra charges.
W
- #WAP (Weighted Average Price)
- The volume weighted average of all tranche purchases in a flexible contract, which is what you are billed at.
- #Water retailer
- The company that bills a business for water and handles meter reads and service. In England any eligible business can choose its retailer; the regional water company still supplies the water. Business water retailers
- #Wholesale price
- The price of energy itself on the traded market, before network, policy and supplier costs are added.
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Book a callThese definitions are general guidance in plain English, not advice on your specific circumstances. Scheme rules, thresholds and charges change, so it is worth confirming the detail for your sites before making a decision.