Glossary of Renewable Energy Terms

A

A-rated:
Energy Performance Certificates ( EPCs) were introduced by the Government in 2008 to encourage improvements in the energy performance of buildings in line with the Kyoto Protocol (see under K). Buildings are rated on a scale of A to G with most modern commercial buildings achieving a rating of C.

Air-conditioning:
Air Conditioning is used to cool air in offices and homes. A compressor compresses a refrigerant gas such as freon so that it heats up. This then runs through an expansion valve, cooling it down. The colder gas then passes through coils and absorbs the heat from air that has been extracted from the building, cooling it down. This cool air is then blown back into the building.

Air source heat pumps
See Heat Pumps

Alternative energy
Usable energy intended to supplement or replace energy derived from fossil fuel sources.

B

BREEAM ( Building Research Establishment Environmental Assessment Method):
An assessment method to rate the environmental performance of buildings. It is the leading and most widely used environmental assessment method for buildings. It sets the standard for best practice in sustainable design and has become the de facto measure used to describe a building's environmental performance.

C

Carbon Dioxide:
Often referred to as CO2, this greenhouse gas is mostly produced by the combustion of fossil fuels, it is an odourless gas which is harmful to the environment.

Carbon Monoxide:
Often referred to as CO, this is a colorless, odorless, and tasteless gas which is slightly lighter than air. It is highly toxic to humans and animals in higher quantities

Carbon footprint
Total amount of greenhouse gas emission caused directly and indirectly by a business or activity.

Carbon Trust
The Carbon Trust works with UK business and public sector to cut emissions of carbon dioxide, and reduce climate change. An independent, not-for-profit company set up and funded by the government to help the UK meet its international climate change obligations; the Carbon Trust creates practical solutions to help businesses cut their emissions, bringing both business and environmental benefits.

CHAS ( Contractors Health and Safety Assessment Scheme):
CHAS is established as the market leader for health and safety pre-qualification in the UK. It is a non-commercial scheme available to suppliers (those who provide goods and services) and to organisations (buyers) looking for suitably competent suppliers.

CO
See Carbon Monoxide.

CO2
See Carbon Dioxide

Climate Change:
A significant change from one climatic condition on Earth to another, currently also referred to as Global Warming (see Global Warming).

Conservation:
Reducing the use of energy by combatting waste and increasing energy efficiency.

Cost effective:
When the money saved by renewable energy and energy efficiency more than pay for the capital and maintenance costs over a given period .

D

DECC
Department for Energy & Climate Change (formerly Department for Environmental Food and Rural Affairs, DEFRA)

E

Emission:
Any substance discharged into the air, earth or water.

Energy efficiency:
The ratio of energy input to energy output. ‘Energy efficient’ usually refers to any change in energy use that results in an increase in net benefits per unit of energy used, thus reducing waste.

Energy Performance Certificates (EPCs):
See A-rated

Energy Saving Trust ( EST)
EST is a largely government funded, independent, non-profit organisation created to manage and co-ordinate various programmes to improve energy efficiency, with a particular focus on the domestic sector.

Energy sources:
There are three categories: Fossil fuels (oil, coal, gas); Nuclear (fission of fusion); Renewables (wind, hydro, geothermal, solar, biomass and wave).

F

Feed-in Tariff
Feed-In Tariffs (also known as FITs) are the electricity part of what some people call Clean Energy Cashback, a scheme that pays people for creating their own "green electricity". The second part of the scheme is the Renewable Heat Incentive, a similar measure for heat.
The tariffs have been introduced by the Government to help increase the level of renewable energy in the UK towards our legally binding target of 15% of total energy from renewables by 2020 (up from under 2% in 2009).

Fossil fuels:
Fuels that are derived from organic matter sediments and formed underground. Common examples include natural gas, coal and petroleum.

G

Global warming:
An increase in the average near surface temperature of the Earth. Usually used to describe the predicted rise in this temperature due to the increase in emissions of greenhouse gases.

Ground source heat pumps
See Heat Pumps

H

Heat Pump:
An energy efficient electric compressor that takes a high volume of low-level heat from one source. This is then transferred to another place as a lower volume of high-grade heat. It operates as a heating and air-conditioning system that uses a refrigeration cycle (where a refrigerant is compressed as a liquid and expanded as vapour to absorb and emit heat.) The heat pump transports heat to a space to be heated during winter and reabsorbs heat from the same space to be cooled during the summer. Heat can be absorbed from the air, ground or ground water.
Types of heat pump:
• Air Source Heat Pump: The most common type of heat pump, it absorbs heat from the outside air and transfers it to the space to be heated. Or, in cooling mode, the heat pump absorbs heat from the space to be cooled and rejects it to the outside air.
• Ground Source Heat Pump: A heat pump in which the refrigerant exchanges heat with a fluid circulating through the ground or ground water. The fluid is contained in a variety of vertical and horizontal pipe layouts depending on the temperature of the ground or water and the ground area available. These heat pumps can use the waste heat from an air conditioning system to provide hot water in the summer.

HVAC
Heating, Ventilation and Air Conditioning. Name given to air conditioning systems that heat, cool, filter or dehumidify a building.

HVCA (Heating and Ventilating Contractors' Association):
HVCA adds value to members' businesses by providing quality services, promoting excellence and shaping the commercial environment through representation and leadership.
The HVCA represents the interests of firms active in the design, installation, commissioning and maintenance of heating, ventilating, air conditioning and refrigeration (hvacr) products and equipment. HVCA members are subject to regular, third-party inspection and assessment to ensure their technical and commercial competence.

K

Kyoto Protocol
Currently covering 160 countries, the Kyoto Protocol is a protocol to the United Nations Framework Convention on Climate Change, an international treaty to reduce emissions of carbon dioxide and other greenhouse gases.

L

Low carbon economy
An economy which has a minimal output of greenhouse gas emissions.

M

( MCS) Micro-generation Certification Scheme
MCS is owned by the Department for Energy and Climate Change (DECC), it is a scheme devised by the UK government to regulate both products and installers operating within the UK market.
Each product from manufacturers must have undergone testing, and the factories visited by accreditation bodies to ensure compliance with ISO 9001. Each installer must undergo evaluation of process and installation capability by the accreditation body.

Micro-Generation
Any power generation equipment that produces less than 50Kw of electricity is classed as micro-generation. This is a figure achievable in homes and small businesses with the use of products such as solar panels and heat pumps.

N

National Grid
A network utility responsible for maintenance of the UK National Transmission System (NTS), transportation of gas and electricity and monitoring supply and demand to ensure a balanced, functional and safe market.

O

Ofgem
The Office of Gas and Electricity Markets. Ofgem is the industry regulator in the UK.

P

Photovoltaic (PV) solar cell:
A system that changes light from the sun into electricity. Can be integrated into large structures for buildings or PV ‘solar farms’.

R

REA:
The Renewable Energy Association represents renewable energy producers and promotes the use of all forms of renewable energy in the UK.

REAL (Renewable Energy Assurance Limited):
The REAL Assurance Scheme was set up by the Renewable Energy Association (REA). Its aim is to guarantee a high quality experience for consumers wishing to buy or lease small-scale energy generation systems for their homes. The REAL Assurance Scheme logo is a sign that the company has agreed to abide by the high standards set out in REAL’s Consumer Code.

Renewal Obligation Certificates ( ROCs):
Digital certificates which hold details of how a unit of electricity is made, who made it and who consumed it.

Renewable Energy:
Energy that is generated from resources that are unlimited. Renewable energy sources include the sun, the winds, flowing water, biomass and geothermal energy.

Renewable Energy Technology:
Devices that utilise renewable energy resources, such as solar panels and wind turbines.

Renewable Heat Incentive( RHI):
The Renewable Heat Incentive is similar to the Feed-in Tariffs, a comparable scheme for electricity which went live in April 2010. The Feed-In Tariffs have done more than anything else to accelerate the installation of renewable energy capacity in Europe. In July 2011, the first phase of the Renewable Heat Incentive will come into force.

Renewables Obligation (UK)
The new Renewables Obligation and associated Renewables (Scotland) Obligation came into force in April 2002 as part of the Utilities Act (2000). It requires power suppliers to derive from renewables a specified proportion of the electricity they supply to their customers. This starts at 3% in 2003, rising gradually to 10% by 2010. The cost to consumers will be limited by a price cap and the obligation is guaranteed in law until 2027.

Renewable Obligation Certificates (ROC's)
Issued by Ofgem, ROC's are given to accredited generators of eligible renewable electricity generated in the UK (for use in the UK). Suppliers must present sufficient ROC's to meet their obligation. One ROC is issued per megawatt hour (MWh) of eligible renewable output generated.

Renewable Resource:
A resource that can be renewed or replenished over a human time scale.

Renewables (Scotland) Obligation:
See Renewables Obligation (UK)

Return on Investment ( ROI):
The comparative term used to assess the return on initial capital investment. Often expressed as a percentage return per year.

S

Solar panel:
A panel that produces either electricity or heat when light shines on it.

Solar PV ( photovoltaics):
The conversion of sunlight into electricity.

Solar Thermal:
Term used to describe systems that capture the sun’s heat for other uses such as hot water.

Sustainable energy sector:
A sustainable energy sector is one which promotes security of supply over time; delivers a low carbon economy and associated environmental targets; and delivers related social objectives (e.g. fuel poverty targets).

U

UK Low Carbon Transition Plan
A government plan plotting how the UK will meet the 34 percent cut in emissions on 1990 levels by 2020.

UK Renewable Energy Strategy
This strategy explains how and why the government intends to increase the UK’s use of renewable electricity, heat and transport.

V

Ventilation:
Ventilation systems are used in buildings to help moisture and heat escape from the building. This helps to keep the building dry, avoiding damage to the structure or materials. Types of ventilation systems include roof and attic ventilation.

W

Watt (W):
A unit of electrical power used to describe the rate of energy consumption of an electrical appliance. One Watt equals one joule per second.