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Glossary

There are many acronyms, technical terms and buzzwords used in the renewable energy and associated industries.

Here is a list of many of them with the relevant descriptions. Terms no longer current are shown in [square brackets and italics].

AAU Assigned Amount Units under the Kyoto emissions trading scheme
ABD Association of British Drivers
ACE The Association for the Conservation of Energy; trade association for energy efficiency suppliers
ACMMO The Association of Coal Mine Methane Operators
AD Anaerobic digestion; the production of methane rich biogas from the process of decomposition in the absence of oxygen
ADL1; ADL2 Building Regulations Approved Documents L1 and L2 on conservation of fuel and power in dwellings (ADL1) and other buildings (ADL2)
AEP The Association of Electricity Producers; trade association representing generators
AGR Advanced Gas-cooled (Nuclear) Reactor
ANM Active Network Management
ARODG Access Reform Options Development Group
Availability The percentage of the time that electricity generating plant is available to produce electricity (also see capacity factor)
[BABFO] The British Association for Biofuels and Oils; the former trade association representing the biofuel industry, now merged into the REA
 BEC  Biomass Energy Centre
BEGA Bilateral Embedded Generation Agreement
BELLA Bilateral Embedded Licence Exemptible Large Power Station Agreement
BER Building Emissions Rating; the design value for a building compared with the TER for compliance with Building Regulations
BERR or DBERR The Department for Business, Enterprise and Regulatory Reform of the UK Government  (largely the former DTI)
BEST BioEthanol for Sustainable Transport
BETTA The British Electricity Transmission and Trading Arrangements, which effectively extended NETA to Scotland
BHA The British Hydropower Association; trade association representing the hydroelectric power industry
Biodiesel An alternative diesel fuel that is produced from animal fats or vegetable oils (including recycled restaurant oils).
Bioethanol A biofuel produced by the fermentation of plants rich in sugar/starch (e.g. sugar cane, corn).
Biogas Methane-rich gas produced by anaerobic digestion of biodegradable material, e.g. landfill gas and sewage gas
[Biogas Association] The former trade association representing the biogas industry, now merged into the REA
Biomass Renewable fuels derived from purpose grown energy crops and the biodegradable proportion of industrial, municipal, agricultural and forestry residues
BiPV Building-integrated photovoltaics
Bl 109 litres, a billion litres
BIS  Department of Business, Innovation and Skills
BRE The (now privatised) Building Research Establishment
[British Biogen] The former trade association representing the biomass industry, now merged into the REA
BSC The Balancing & Settlement Code; The governance of electricity dispatch and settlement in England & Wales (and Scotland following the introduction of BETTA)
BSUoS Balancing Services Use of System Charges; the means by which the TSO can recover the costs of balancing the system
Buy-out fund The fund derived from Renewable Obligation suppliers who ‘buy-out’ from their obligation to submit ROCs in respect of a proportion of their electricity sales
Buy-out fund recycling The redistribution of the buy-out fund back to the electricity suppliers in relation to their proportion of the total ROCs redeemed in that year
BWEA The British Wind Energy Association; trade association representing the wind energy industry
C5 Five carbon monomer e.g fructose (a pentose)
C6 Six carbon monomer e.g glucose (a hexose)
CAP CUSC Amendment Proposal
Capacity See Rated capacity and DNC
Capacity factor The ratio of the electrical energy produced by a generating unit relative to the electrical energy that could have been produced at continuous full-power operation during the same period
Carbon Trust A Government-funded organisation to promote carbon reduction in business and the public sector
CBM Coal Bed Methane; gas actively extracted from coal seams
CCA Climate Change Agreement; consumer contract to mitigate climate change impacts linked to concessions under the Climate Change Levy
CCL The Climate Change Levy
CDM Clean Development Mechanism; means whereby Parties not included in Annex I in of the Kyoto Protocol can achieve sustainable development and to assist Parties included in Annex I in achieving compliance
CEC Connection Entry Capacity
CERs Certified Emissions Reductions These are tradable units generated by projects in developing countries under the Clean Development Mechanism (CDM).
CERT The Carbon Emission Reduction Target (previously the Energy Efficiency Commitment - EEC)
CESP The Community Energy Saving Programme a proposed new legal obligation on the energy companies to invest in energy efficiency measures.
CH4 Methane
CHP Combined Heat & Power; the use of both heat and electrical power from a thermal power station
CHPA The Combined Heat and Power Association; trade association representing CHP operators and developers
CISG Charging Issues Sub Group
CLA The Country Land and Business Association, representing land-owners
CLG or DCLG The Department for Communities and Local Government of the UK Government
Climate change The long term variations in the world and regional climates, now commonly attributed to the impact of mankind
CMG Compressed Methane Gas
CMM Coal Mine Methane; the gas continuously emitted by coal mines especially non-working mines
CNG Compressed Natural Gas
CO2 Carbon dioxide
Co-firing The burning of mixed fuels (typically refers to biomass with fossil fuel in a coal-fired power station)
COG Commercial Operations Group (of DNOs in the ENA)
COP Coefficient of Performance - the ratio of the energy output divided by the energy input - a measure of the effectiveness of a heat pump
CPA The Construction Products Association; a trade body for the suppliers of building products
CPET  Central Point of Expertise on Timber
CROC Co fired ROCs
CUSC Connection & Use of System Code; Governance arrangements for connection to the transmission system
CVA metering Metering that is registered in the Central Volume Allocation system (typically larger generation and consumers at the ‘wholesale’ level). See also SVA metering
D Code Covers all major technical aspects relating to connections to, and the operation and use of, the distribution network
DC Data collector; agent responsible for obtaining metering data on behalf of the electricity supplier and preparing it for electricity settlement
DCISG Distribution Charging Implementation Steering Group
DCRP Distribution Code Review Panel
DCUSA Distribution Connection Use of System Agreement
DDGS Distillers Dry Grains with Solubles
DECC  The Department of Energy and Climate Change of the UK Government
DEFRA The Department for Environment, Food and Rural Affairs of the UK Government
DETI or DETINI The Department of Enterprise Trade and Investment of the UK Government in Northern Ireland; equivalent of BERR
DfT The UK Government Department for Transport
[DGCG] The Distributed Generation Co-ordination Group; body which advised Ofgem and the DTI on the effects of distributed generation on the UK electricity network now replaced by ENSG
DGEN Distributed Generation & Electricity Networks (A DTI programme)
Disclosure The requirement (under the IEMD) on electricity suppliers to provide details to consumers of the fuel sources of the electricity they have purchased
DISI Direct Injection Spark Ignition
Distributed generation Power generation embedded in (connected to) an electricity distribution network (as compared to centralised generation connected to the transmission network)
Distribution Code The code of practice, which covers all major technical aspects relating to connections to, and the operation and use of, licensed distribution networks
Distribution network The network for electricity distribution at voltages below that of the transmission network
DME DiMethyl Ether
DNC Declared Net Capacity; a correction factor applied to the rated capacity of some intermittent generation sources to enable like-for-like comparisons with typical thermal plant capacity
DNO Distribution Network Operator
DPCR Distribution Price Control Review
DPFS Diesel Particulate Filter System
DRM Distribution Reinforcement Model
DSM Demand Side Management
[DTI] The Department of Trade and Industry of the UK Government, now reconstituted mostly into BERR – see above
DUKES The Digest of UK Energy Statistics from BERR
DUoS Distribution Use of System
DWG The Distribution Working Group; a body advising Ofgem and BERR on the effects of distributed generation on the UK electricity network
E100 Ethanol fuel type using 100% bioethanol fuel (As opposed to E85)
E85 Ethanol fuel type Ethanol vehicles can take up to 85% ethanol and 15% petrol mix to run
EA The Environment Agency; The regulator for the environment, including rivers and waste disposal
[EA] Electricity Association; a trade association representing the ESI, which was disbanded in 2003, its primary activities having been transferred to the AEP, and the new ENA and ERA
ECA Enhanced Capital allowance; a tax allowance for investment in certain prescribed items of equipment, including some renewable energy devices
[EEC] Energy Efficiency Commitment whereby companies can be rewarded for obtaining agreed improvements in energy efficiency now called CERT
EFV Environmentally friendly vehicle
EfW Energy from waste
EGR Exhaust Gas Recirculation
EI The Energy Institute, created from the merger of the former Institute of Petroleum and the Institute of Energy
EIC 1 Energy Industries Council; a Trade Association for UK companies that supply capital goods and services to the energy industries world-wide
EIC 2 Energy Information Centre
EIC 3

Environmental Industries Commission; a company which lobbies on behalf of members in the environmental industries
Elexon The company that administers the Balancing and Settlement Code
Embedded benefits Commercial benefits arising from generation connected to distribution networks, e.g. the avoidance of BSUoS, TNUoS, BSC charges, transmission losses and Residual Cashflow Reallocation
Embedded generation See distributed generation
ENA Electricity Networks Association; trade association representing electricity and gas transmission and distribution network operators, formed following the disbanding of the EA
End-fuel A fuel that can be used directly to power a vehicle
Energy efficiency The amount of useful output achieved for each unit of input energy. Energy efficiency can be improved by reducing wastage both in the equipment and its use
Energy mix The distribution of different energy sources within the total supply
Energy security The extent to which a nation’s or region’s energy supplies are robust against potential disruption, including factors such as depletion of natural resources, variability and the political stability of regions where the energy supplies are obtained or trans-shipped
EFIP  English Forest Industries Partnership
ENSG Electricity Network Strategy Group
EPBD Energy Performance of Buildings Directive
EPC Energy Performance Certificate; a component of the HIPs
EPI Environmental Performance Indicator
EPSRC The Engineering and Physical Sciences Research Council
ERA Electricity Retail Association; trade association representing suppliers formed following the disbanding of the EA
ERD European Renewables Directive
ERUs Emission Reduction Units These are tradable units generated by projects in developed countries under the emissions trading Scheme
ESA The Environmental Services Association; a trade body for the waste management industry
ESCo An energy services company
ESI Electricity Supply Industry
ESQCR Electricity Safety Quality and Continuity Regulations 2002; The statutory instrument in relation to the distribution of electricity
EST The Energy Saving Trust; a Government organisation to promote energy efficiency to domestic, business, local government and trade sectors
ETBE Ethyl Tertiary Butyl Ether
ETG The Emissions Trading Group; a body now constituted as an industry association advising the UK Government on the implementation of the EU ETS, and its inter-relationships with UK ETS, CCAs and other measures
EtOH Ethanol
[ETSU] The Energy Technology Support Unit formerly of the DTI, now the privatised Future Energy Solutions
EU ETS The Emissions Trading Scheme of the European Union
EUA EU Allowance These units are specific to the EU emission Trading Scheme, (EU ETS)
 EWGS  English Woodland Grant Scheme
Externalities The external impacts associated with power generation, but not traditionally costed into the energy price
FAME Fatty acid methyl ester
FC Stack Fuel cell stack
F-Cell See Fuel cell
FCEV Fuel Cell Engine Vehicle
FCHV Fuel Cell Hybrid Vehicle
FCHV-BUS Fuel Cell Hybrid Bus
FCV Fuel Cell Vehicle
Feed-in Tariff A renewable energy support mechanism used in certain countries, where producers are rewarded at a nationally prescribed level for renewable electricity fed into the grid
FFV Flex Fuel Vehicle
Fischer Tropsch A catalytic system for reformulating gasifier-derived syngas
FSL Final Sums Liabilities
FTSE4Good Index Stocks and shares ratings of companies with 'good' social, ethical and environmentally responsible ratings
Fuel Cell A device that derives energy from (normally) liquid fuels such as hydrogen by chemical conversion
G(number) Engineering recommendation documents, published by ENA
g/km Grams per kilometer - unit measurement of CO2 used to categorise the emissions of different vehicles
GBSQSS Great Britain Security and Quality of Supply Standard
GCOF Government Carbon Offsetting Fund A fund to offset travel from official and Ministerial air travel
GCRP Grid Code Review Panel
GDUoS Generator Distribution Use of System
GEMA Gas and Electricity Markets Authority; regulatory part of Ofgem
Generation The energy output of a generating plant over a period of time
GJ Gigajoule (109 joules, one thousand MJ)
Global warming A widely used expression for Climate Change
GO; GoO Guarantee of Origin
GRC Gross Registered Capacity
Green smear-back See buy-out fund recycling
Greenhouse gases; GHG Gases whose emission contributes to climate change; The Kyoto Protocol identifies these as Carbon dioxide, Methane, Nitrous oxide, Hydrofluorocarbons, Perfluorocarbons and Sulphur hexafluoride
Grid Code The code of practice, which covers all major technical aspects relating to connections to, and the operation and use of, the transmission system
GTNUoS Generator Transmission Network Use of System (charges)
GW; GW(e); GW(th) Gigawatts (109 watts, one thousand MW); gigawatts electrical; gigawatts thermal
GWh Gigawatt-hours
Ha Hectare = 10,000m2
HBF The House Builders Federation; a trade body for the house building industry
HCA The Homes and Communities Agency
Hexose Six carbon (C6) sugar e.g glucose
HFCs Hydrofluorocarbons
HIPs Home Information Packs; a legal requirement for the sale of certain houses in England and Wales, including an Energy Performance Certificate (EPC)
HMSO Her Majesty’s Stationery Office
IC Internal Combustion
ICEV Internal Combustion Engine Vehicle
I Chem E The Institution of Chemical Engineers
ICRP Incremental Cost Related Pricing
ICW Industrial and Commercial Waste
[IEE] The Institution of Electrical Engineers (now part of IET)
IEMD Internal Electricity Market Directive
IET The Institution of Engineering and Technology, created from a merger of the previous IEE and IIE
IFI Innovation Funding Incentive – a mechanism to encourage DNOs to invest in appropriate R&D activities
[IIE] The Institution of Incorporated Engineers (now part of IET)
I Mech E The Institution of Mechanical Engineers
Intermittency

A pejorative term often misused for renewables which are variable in output. Large (non-renewable) generators are much more intermittent as when they fault, their output goes to zero instantaneously.
ISG Implementation Steering Group for the Structure of Electricity Distribution Charges
J Joule
JI Joint Implementation A means for companies in developed countries to undertake emission reduction projects in other countries with a Kyoto target
kJ Kilojoule (103 joules, one thousand Joules)
ktoe Thousand tonnes of oil equivalent
kVA One thousand volt-amps; similar to one kW
kW; kWh Kilowatt (103 watts, one thousand watts); kilowatts electrical; kilowatts thermal
kWh Kilowatt hours
LANTRA Sector Skills Council for Environment and Land Based Sector
LATS Landfill Allowance Trading Scheme
LCBP The UK government's Low Carbon Building Programme
LCPD Large Combustion Plant Directive
LCV Light Commercial Vehicle
LEC (Climate change) Levy Exemption Certificate
LEG Licence Exempt Generator; an electricity generator too small (<100MW) to be required to hold a generation licence
Load factor See capacity factor
LowCVP Low Carbon Vehicle Partnership
LPG Liquid Petroleum Gas
LRIC Long Run Incremental Cost
LZC Low and zero carbon
Magnox 1st Generation of commercial nuclear reactors in the UK
MBT Mechanical / biological treatment of waste
MBT Mechanical and Biological Treatment
MCS Microgeneration Certification Scheme setting standards for onsite renewables products and installers, and linked to the REAL Code
MeOH Methanol
Merton Rule A planning requirement applied by local authorities to mandate energy efficiency and renewable energy as a condition for planning approval. The first was applied by Merton Borough Council requiring 10% onsite renewables for developments over 1,000m2
Mha 106 ha
MI 106 Litres
MITC Main Interconnected Transmission Circuits
MJ Megajoule (one thousand kJ)
MO; MOA Meter Operator (Agent); responsible for installation, safety and maintenance of metering equipment on behalf of the electricity supplier/meter registrant
MPAN Metering Point Administration Number; The registration number of a metering point used in electricity settlement
MPV Multi-purpose-vehicle (People carriers)
MRA Master Registration Agreement; The multilateral framework agreement for the retail (SVA) level procedures of registration and transfer
MSW Municipal Solid Waste
MTBE Methyl Tertiary Butyl Ether
Mtoe Million tonnes of oil equivalent
MW; MW(e); MW(th) Megawatts (106 watts, one thousand kW); megawatts electrical; megawatts thermal
MWh Megawatt-hours
N2O Nitrous Oxide (global warming potential = 310 x CO2)
NAP National Allocation Plan for the level of emissions permitted under the EU ETS
[NETA] The New Electricity Trading Arrangements; introduced in March 2001 for England and Wales and governed by the BSC and replaced in 2004 by BETTA
NFFO Non Fossil Fuel Obligation
NFPA; NFPAS Non-Fossil Purchasing Agency, which administers the NFFO contracts and auctions NFFO energy and ROCs; and the equivalent dealing in SROCs for Scotland
NFU The National Farmers Union; a representative body for UK farmers
NGC; NGT National Grid Company, part of National Grid Transco; the GB Transmission System Operator for electricity and gas under BETTA
NHBC National House Building Council; a body which underwrites the building standards of its members
NIAER Northern Ireland Authority for Energy Regulation; created on 1 April 2003 (see also Ofreg)
NIE Northern Ireland Electricity, part of the Veridian Group
NI-NFFO Northern Ireland NFFO
NIROC Northern Ireland ROC
NIWT National inventory of woodland and trees
NOx Nitrous oxide and other oxides of nitrogen
NPPG National Planning Policy Guidance documents published by the Scottish Executive
[ODPM] The Office of the Deputy Prime Minister, disbanded in 2006 with the major renewable energy related elements now in CLG
Odt Oven dry tonne
OETWG Offshore Electricity Transmission Working Group
Ofgem The Office of Gas and Electricity Markets; the energy regulator for GB and the RO administrator (see also GEMA)
Ofreg The Office for Regulation of Electricity & Gas; the energy regulator for Northern Ireland, see also NIAER
OFT The Office of Fair Trading; part of BERR dealing with consumer protection and trading standards
ON Operational Notification
OTEG Offshore Transmission Experts Group
P(number) BSC modification proposal, published by Elexon
PBS Polybutylene Succinate
Pentose Five carbon (C5) sugar e.g fructose
PFCs Perfluorocarbons
PFE
  Public Forest Estate
[PIU] The Performance and Innovation Unit of the Cabinet Office
PJ Petajoule (1015 joules, one thousand TJ)
PPA / PPC Power Purchase Agreement / Power Purchase Contract
PPO Pure plant oil
PPS [formerly PPG] Planning Policy Statements (formerly Planning Policy Guidelines), published by CLG. PPS22 deales with renewables
PV Photovoltaics
[PV-UK] The UK Photovoltaics Association; the former trade association representing the PV industry, now merged into the REA
R&D Research & Development
RAB The Renewables Advisory Board established by the DTI (now BERR)
Rated capacity The power rating of a generating station, (usually in kVA or MW) at which it would operate under the design operating conditions and input fuel (or resource – e.g. wind speed)
RCEP The Royal Commission on Environmental Pollution
RD&D Research, design and development
RDD&D Research, design, development and demonstration
RDF Refuse derived fuel, usually solid pellets of fuel derived from waste using MBT also called SRF
RDPE  Rural Development Programme for England
RE Renewable energy
REA Renewable Energy Association; trade association representing renewable energy producers of all types – that’s us!
REAL Renewable Energy Assurance Limited, which administers the REA-sponsored REAL Code of conduct for renewables supplied to consumers
REAL Code The Code of conduct for suppliers of onsite renewables sponsored by the REA and administered by REAL. Linked to the MCS.
RECS Renewable Energy Certification Scheme; pan-European certificate trading system
RED European Renewable Energy Directive
REGO Renewable Energy Guarantee of Origin
Renewable energy Energy flows that occur naturally and repeatedly in the environment and can be harnessed for human benefit, which are naturally replenished (renewable).
Renewable Portfolio Standards A renewable energy support mechanism used mainly in certain states of the USA to encourage energy suppliers to produce a certain proportion of their energy from prescribed renewables
RES The UK's Renewable Energy Strategy
RES-E Electricity produced from Renewable Sources (term used in ERD)
RHI Renewable Heat Incentive
RME Rapeseed Methyl Ester
RMIF		 Retail Motor Industry Federation
RO; ROS The Renewables Obligation and the Renewables Obligation(Scotland)
ROCs Renewables Obligation Certificates, the ‘currency’ of the RO
ROCOF Rate of Change of Frequency


RPA The Rural Payments Agency of DEFRA
[RPA] Renewable Power Association – the former name for the REA
RPZ Registered Power Zone; areas where DNOs develop and demonstrate new, more cost effective ways of connecting and operating generation on their systems
RTF Renewable Transport Fuel
RTFO Renewable Transport Fuels Obligation
RTMA ROC Trading Master Agreement; the proforma contract for trading ROCs
SAP The Standard Assessment Procedure used to calculate the energy rating of dwellings for compliance with Building Regulations and other purposes
SBEM The Simplified Building Energy Model used to calculate the energy rating of non-residential buildings for compliance with Building Regulations and other purposes
SBP System Buy Price
SCR Selective Catalytic Reduction
SEPA Scottish Environmental Protection Agency
SEPAB The Sustainable Energy Policy Advisory Board which advises SEPN
SEPN The Sustainable Energy Policy Network established by DTI, DEFRA and ODPM
SHETL Scottish Hydro Electric Transmission Ltd
SI Government secondary legislation known as a Statutory Instrument
SME Soya Methyl Ester
Smear-back See buy-out fund recycling
SMMT Society of Motor Manufacturers and Traders
SO System Operator
SONI The transmission system operator for Northern Ireland (NIE)
SO-TO Code System Operator to Transmission Owner Code
SOx Sulphur dioxide and other oxides of sulphur
SPTL Scottish Power Transmission Ltd
SQSS Security and Quality of Supply Standard
SRC Short Rotation Coppice; perennial crop of tree species planted at high density and typically harvested at 3 year intervals
SRF The Scottish Renewables Forum an industry association for renewables businesses in Scotland
SRF Solid recovered fuel, another expression for RDF
SRF
 Short Rotation Forestry
SRO The Scottish Renewables Order; the equivalent of NFFO in Scotland
SROCs Scottish ROCs
SSEG Small-Scale Embedded Generator; a small generating plant connected to the electricity distribution network, for some purposes implies a rating of 16 amps or less per phase
SSP System Sell Price
SU-LEV Super Ultra Low Emissions Vehicle
SVA metering Supplier Volume Allocation Metering. The metering normally required for most smaller generators and consumers and registered by suppliers for electricity settlement purposes. See also CVA metering
SVO Straight Vegetable Oil
SWA
 Small Woods Association
TADG Transmission Arrangements for Distributed Generation
TASG

Transmission Access Standing Group
TCMF Transmission Charging Methodology Forum
TCPA The Town and Country Planning Association
TEC Transmission Entry Capacity
TER Target Emissions Rating; the standard value against which the BER is compared for compliance with Building Regulations
TIWG Transmission Issues Working Group
TJ Terajoule (1012 joules, one thousand GJ)
TNUoS Transmission Network Use of System; charges made by the TSO to users of its system
TO Transmission Operator
toe Tonne of oil equivalent
Tonne One thousand kilogrammes
Transmission network The electricity transmission system operating at voltages above 132kV (and including 132kV in Scotland)
Triad 3 Times of Transmission System Peak Demand, each separated by 10 days
[TSG] Technical Steering Group (of the DGCG) now superseded by the DWG of the ENSG
TSO (Electricity) Transmission System Operator
TULS Time of Use Location Specific
TW; TW(e); TW(th) Terawatts (1012 watts, one thousand GW); terawatts electrical; terawatts thermal
TWh Terawatt hours
UCO Used Cooking Oil
UK ETS The Emissions Trading Scheme of the UK, progressively being replaced by the EU ETS
UKBCSE UK Business Council for Sustainable Energy; grouping of participants in the energy sector interested in promoting sustainable energy
UNFCCC United Nations Framework Convention on Climate Change

Variability

The non-continuous nature of some forms of energy generation, e.g. wind power, solar, hydro, wave and tidal which with good forecasting can be very predictable.
 

VED

  

Vehicle Excise Duty (Road Tax)
VERs Voluntary Emissions Reduction Credits Non official carbon credits, not recognised by, and not forming part of, the Kyoto protocol or EU ETS.
VME Vegetable Methyl Ester
VOC Volatile Organic Compounds
WDS Wet Distillers Grains
WFD Water Framework Directive
WID Waste Incineration Directive
WIG Woodland Improvement Grant
WRAP Waste & Resources Action Programme
WVO Waste Vegetable Oil
ZEV Zero Emission Vehicle