Glossary

Term

Explanation

A

A/C 

Air conditioning

Air receiver

Components of the compressed air system that receive air and provide compressed air storage capacity.

Air tightness level (buildings)

The degree of air leakage or air infiltration in a building

Amp (Ampere)

A measure of electrical current in a circuit

B

Ballast

A lighting component that controls the current in a lamp.

Bar

A unit of for measuring pressure

Bar(g)

Bar gauge

Black-bulb thermostat

A control thermostat normally used in radiant heating systems

Blank screen-saver (computers)

Computer screen saver that leaves the screen blank.

Blowdown (boiler)

In a boiler, it is the process of expeling water, dissolved and suspended solids in that water and sludge.

Blow-off device (compressed air)

Air amplifying device capable of delivering high volume air flow.

BMS (Building Management System)

An automated system for managing a building's services and other related aspects

Boiler flow temperature

The temperature at which the water leaves the boiler in a wet heating system

Btu

British Thermal Unit: a unit for measuring the quantity of heat energy necessary to raise the temperature of one pound of water one degree fahrenheit.

Building controls

Units or systems used to control building services such as heating or lighting

Burner damper (boilers)

A movable plate used to control air flow to the burner in a boiler

C

Calibrate

The process of checking and re-establishing the accuracy of a measuring instrument, e.g. a digital thermometer

Calorifier (hot water)

A pressure vessel containing tubes through which hot water passes.

Cathodic protection

A treatment used to prevent corrosion of a metal by making the metal a cathode

Centrifugal compressor

Compressors that generate pressure by increasing the air's velocity using a rotating impeller.

CER

Commission for Energy Regulation

CFL

Compact Flourescent Light

CHP 

Combined Heat and Power

Circulating pump (hot water)

Pump used to keep (hot) water circulating through a distribution system

CO₂

Carbon Dioxide

Co-efficient of Performance (COP)

A measure of the effectiveness of an air conditioning unit (or chiller) in converting electricity into cooling or heat. Once you buy a unit, the COP cannot be changed. For a given appliance, the COP in cooling mode will differ from the COP in heating mode. Usually the COP will be supplied with an appliance?s technical literature. If it is not given it may be calculated simply: COPcooling = rated cooling output [kW] / rated electricity input [kW]. < /P > < P >  < /P >< /P >< /P >< /P >< /P >< /P >< /P >

Combined heat and power (CHP)

A unit that simultaneously generates heat and electricity. Also knows as 'cogeneration'

Compact fluorescent lamp

A compact low energy lamp

Compressed air eductor

Air powered device which uses Venturi effects to move air

Condensate (compressed air)

The product of the condensation of water vapour in the air entering a compressor. Condensate is often contaminated with particles and oil and must be removed and properly disposed.

Condensate (steam)

Condensed steam

Condenser (outdoor unit)

The device in which a refrigerant condenses from a gas to a liquid when it is depressurized or cooled in an air conditioning, refrigeration or heat pump system

Condenser coil

The coils through which a refrigerant is circulated and releases heat to the surroundings in an air conditioning, refrigeration or heat pump system.

CRT computer screen

Cathode ray tube computer monitor. These are the traditional 'bulky' screens as opposed to the modern flat screens.

CUSUM

Cumulative sum. A technique for analysing energy data that uses the difference between the base line (expected or standard consumption) and the actual consumption over the base line period of time.

D

DCMNR

Department for Communications, Marine and Natural Resources

Damper (flue)

A movable plate used to control flue gas flow

Degree Days

A unit for measuring the extent to which the outdoor daily average temperature falls below an assumed base temperature, usually 15.5^oC. They are used to take into account the changes in the weather (temperatures) in analysing heating energy use.

DG

Distributed Generation

DHW

Domestic Hot Water

Digital thermometers

Thermometers that display results in digital format.

Discharge lamp

A lamp in which light is produced by an electric discharge through a gas, metal vapour or a mixture of gases and vapours

DSO

Distribution System Operator

E

Electro-magnetic control gear

Lighting control gear that consists primarily of transformer-like copper windings on a steel or iron core 

EMAS

Eco Management and Audit Scheme

EMS

Energy Management System

Energy Manager

The person responsible for the management of energy within an organisation.

Energy Map Audit

An audit of the operation of the Energy MAP.

Energy MAP Review

A review of the the operation of the Energy MAP. Top management are responsible for carrying out the management review of the Energy MAP

Energy performance indicator

A value against which you compare your energy performance.

Energy Star

A US and European programme for the classification of energy efficient products

Energy Star Label

The label used by the Energy Star programme to identify energy efficient products

Energy Team

A group established to manage energy within an organisation.

Environmental label

Labels used to identify environmentally preferable products.

ESCO

Energy Services Company

European Eco-Label

The environmental label of the European Union used to identify environmentally preferable products and services

European Union Energy Labels

A European Union label that provides information on a product?s energy consumption and rates it on a scale of A to G, with A being the most efficient

.

Evaporator (Indoor unit)

A mechanical device that transforms a liquid into a gaseous state.

Exposed thermal mass

Refers to a building's capacity to absorb heat energy. Materials such as concrete slabs have a high thermal mass, and if left exposed within a building can be used to absorb heat and therefore moderate internal temperatures.

F

Fan coil unit

A unit in which a fan blows air over a heat exchanger coil containing a circulating fluid and distributes heat or cool air to different areas.

FLA (Full load amps)

The current (amperage) drawn by a motor when operating under full load

Flat screens

Modern computer monitors that are 'flat' in appearance and use less energy than the traditional computer monitors. These employ TFT LCD technology used in portable computer screens.

Flow restrictor

Device that reduces the quantity of water flowing through a water tap or pipe

Flue damper

A movable plate used to control air flow in the flue.

Flue gas analyser

A devices for analysing the gas resulting from the combustion of a fuel that is emitted to the flue.

Frost protection thermostat

A heating system thermostat used to prevent damage in the event of frost and low external temperatures.

Full load amps

The current (amperage) drawn by a motor when operating under full load

G

Grip-on ammeter

A portable device that can be freely attached to an electric cable and used to measure current

gW

Gigawatt

gWh

Gigawatt hour

H

Heat removal

The removal of heat from a source or area

Hibernate (computers)

The state of activity of a computer when least energy is being used

High bay fittings (lighting)

Usually refers to industrial or retail lighting mounted at about 5m or more above ground level.

High frequency control gear

Lighting control gear that typically operate fluorescent lamps at high frequencies. These are based on state electronic components and help reduce lighting energy consumption.

Humidistat

A device for measuring the relative humidity in the air

Humidistat control

Control based on the relative humidity of the air in a space

HVAC

Heating, Ventilation & Air Conditioning

Hydraulic tool

Tool that operate using hydraulic principles

I

Infra-red coated halogen lamps

A halogen lamp is an incandescent lamp with a filament that is surrounded by halogen gases. An infra-red coating can be placed on the filament tube to redirect infra-red heat back on to the filament thus increasing its temperature and resulting in less electrical energy being required.

Incandescent lamp

A lamp in which a filament is heated by an electric current to produce light. These are the familiar light bulbs you use at home.

Interdisciplinary design team

A building design team that contains members from different disciplines, such as architects, engineers, quantity surveyors etc.

ISO 14001

The international standard for environmental management systems

Isolation valves (heating system)

Isolation valves: valves that control the distribution of heating or hot water to specific areas or zones

J

Joule

A measure of energy

K

Kilowatt hour (kWh)

A unit of energy. Often in relation to electricity, but also for other fuel sources. One kWh is the energy used by a 1000 Watt device (kilowatt) running continuously for one hour.

kVa

Kilo volt amps, a unit of power

kW

Kilowatt

L

LED

Light emitting diode

Legionella

Bacteria that causes Legionnaires' Disease

Level of Air-tightness

The amount of air leakage or air infiltration in a building

Light meter

A device that measures the light level (illuminance) at a surface or location.

Limescale

Deposits of lime that form as a result of water flow in pipes and equipment

LNG

Liquefied natural gas

Low voltage halogen lamps

Low-voltage tungsten-halogen lamps are incandescent lamps that use a halogen gas surrounding the filament and operate at 6V, 12V and 24V ratings.

LPG

Liquid Petroleum Gas

LTHW

Low temperature hot water

Lumen

The unit that describes the quantity of light emitted by a lamp or received at a surface

Lumens per watt

The amount of lumens produced per watt of power

LUX

The unit used to measure 'Illuminance', which is the amount of light falling on a surface of unit area. One lux is equal to one lumen per square metre.

M

Mains voltage mini-CFL fittings

Small compact fluorescent fitting that can be connected to the mains voltage

Maintenance strategy

The approach to maintenance, whether it be reactive, planned or other strategies

Maximum Demand

Maximum Demand is the highest level of electrical demand in the monitored period. This is monitored during particular intervals and used for a specific type of electrical tariff where a special meter records the maximum demand for electricity at short intervals, e.g. each half hour or fifteen minute period.

MEC

Maximum Export Capacity

Mechanical heat removal

Removal of heat from a building or process by mechanical means, e.g. by means of extractor fans

Mercury vapour lamp

A lamp in which light is produced by an arc between two electrodes surrounded by mercury vapour.

MIC

Maximum Import Capacity: 

MoU

Memorandum of Understanding

MRSO

Meter Registration System Operator

mW

Megawatt

N

NO₂

Nitrogen dioxide

Natural heat removal

Removal of heat from a building or process by natural means, i.e. without the aid of mechanical or electrical plant or equipment

Night hours (electricity tarriffs)

The period of time during the night used for the application of certain electricity tarriffs. Under Maximum Demand tariffs day and night units are separately metered.

Night load (electricity tarriffs)

Electricity load during night hours

Normalise

Refers to a process of treating energy data in order to deal with external influencing factors

Nox

Nitrogen oxides

O

O & M

Operation and maintenance

Objective

A site goal that is consistent with the energy policy and takes significant energy users and energy saving opportunities into account.

Optimum start

A heating system control that adjusts heating start up times according to external weather conditions. Heating is turned on later on milder days as shorter warm-up times are required.

Oxygen trim control

A method of controling the amount of air (oxygen) delivered for fuel combustion.

P

Parameters and settings of the building control strategies

Criteria used to establish control strategies for building services. Criteria could include operational hours, daylighting, weather conditions and others.

Payback period

The time taken for a project to recover its outlay. For energy saving projects, payback in simple terms is the capital cost divided by average annual savings.

Performance based specifications

Specification of a particular performance level for the item rather than identifying the technical characteristics in detail. In essence, it specifies the end result, but not how to achieve it.

Pneumatic tool

Tool that operate using air pressure

Post project evaluation

The evaluation of a project after it has been implemented.

Power factor correction capacitors

Power factor is the ratio of actual power being used in a circuit, expressed in watts or kilowatts, to the power that is apparently being drawn from a power source. By installing capacitors the Power Factor can be altered.

Power logger

A device for recording electrical power

Predictive maintenance

Maintenance based on analysis of the condition of an item or facility that checks if it is operating as required, and if not, corrective action is taken.

Pressure-regulating valve

Valves that regulate the pressure in a compressed air system

Preventative maintenance

Maintenance actions performed on the basis of a set time or run-time interval.

Process vapour or aerosol

The end result of atomising a liquid using compressed air.

PSI

Pounds per square inch (an Imperial unit for measuring pressure)

Pulsation dampening

The dampening of the pressure pulsations typically associated with reciprocating compressors

PV

Photovoltaic. PVs convert solar radiation (energy from the sun) into electricity.

Q

Quad

One quadrillion (10¹⁵) BTUs: An amount of energy equal to 170 million barrels of oil. 

R

R & D

Research and development

R²

Mathematical notation for 'goodness of fit' or level of relationship between 2 or more variables

Radiant heating

A heating system that transfers heat to objects and surfaces within a space primarily by (infrared) radiation.

Rated cooling output

The cooling output of a device under specific or nominal operating conditions

Rated electricity input

The electrical output of a device under specific or nominal operating conditions

RE

Renewable energy. This includes solar, wind, wave, hydro, geothermal and biofuels such as wood, waste and energy crops.

Reciprocating compressor

Compressor driven by a piston having a reciprocating motion in a cylinder.

Refrigerant sight glass

A 'window' where you can observe the coolant liquid in a refrigeration circuit.

Regression analysis

A technique for analysing energy data that analyses the association between one (dependent) variable and one or more other (independent) variables 

Relative humidity

The amount of water in the air or more precisely the ratio, in percent, of the actual amount of water vapor in a body of air to the maximum amount that body can hold at a given temperature.

Reliability centered maintenance (RCM)

A process used to determine the maintenance requirements of a physical asset in its operating context. Essentially RCM prioritises maintenance according to the importance of an item and the probability of failure and matches these with the resources available.

Resources

Inputs into a process, including capital, labour and land

Retrofitting

The activity of replacing existing plant, equipment, fixtures or fittings

Review

An assessment of performance and operation

Rotary screw compressor

Compressor driven by two rotors within a casing where the rotors compress the air internally

S

Sequence control

The control of two or more equivalent items of plant in order to achieve optimum performance. For example, boiler sequence controls may operate two or more heating boilers in order to achieve optimum performance of the heating system.

Set point

The point at which the desired operating parameter is set

Set point (temperature)

The point at which the desired temperature of a heated or cooled space is set

Short cycling (boilers)

A condition in which a boiler fires even though there may not be a real heating or hot water demand.

SO₂

Sulpher Dioxide

SON

High pressure sodium lighting.

Split air conditioning unit

Small packaged air-conditioning units are proliferating. They are often referred to as DX (direct exchange) units, or split a/c units. Each unit has an indoor unit (evaporator) and outdoor unit (condenser). They are generally installed to provide cooling, but are generally capable of heating too. 

Standby (operation)

The condition in which an item of equipment is ready for operation but not in operation. Stanby conditions should use less power

Standing losses (boilers)

Boiler casing losses and stack ventilation losses during boiler on and off periods.

Steam trap

An automatic control valve that allows for the release of condensate and non-condensable gases while maintianing steam in the system.

Sub-meter (electricity)

Usually refers to meters that are not 'main' meters that directly record electricity supply

T

T5 fluorescent lighting

Fluorescent (tube) lamps with a diameter of 16 mm

Target

A detailed performance requirement (quantified wherever practicable) based on an objective.  The target contributes to achieving the stated objective.

Tariff

The payment scheme used for you electricity/gas use

Temperature setpoint

The point at which the desired temperature of a heated or cooled space is set

Thermostat

A device for measuring the temperature in a space

Thermostatic radiator valves

Valves attached to a heat emitter or radiator that directly control its temperature

Three phase load (3-phase load)

Phase is a term used to describe alternating current. To distribute AC power it is more efficient to use three circuits that are 'out of phase', with the result that there is always voltage in at least one wire. Three-phase power removes the need for a neutral or 'return path'.

Total dissolved solids (TDS)

The solid particles that are dissolved in steam or water.

Total productive maintenance

An approach to maintenance that brings different functions together such as operations, maintenance, purchasing and other support services to develop and implement a formal structure for maintaining a building, plant, fixtures and fittings.

TSO

Transmission System Operator

U

Uninterruptible Power Supply (UPS) system

An alternative power source used to power equipment if normal power service is interrupted or falls below acceptable levels.

Unit of Energy

different fuels are metered in different units: kWh, BTU, litre or M³

V

Vacuum eductor

Device used with compressed air to generate a vacuum. This is a more expensive way of generating a vacuum and should be replaced with motor driven vacuum pumps.

Variable speed drive

Motor drives that can operate at different speeds

Variable speed inverter

Variable frequency controller that controls drive speed

W

Wattless Charges

Wattless Charges are caused by the operation of specific electrical load on your site as some items using power may require an amount of wattless energy for their operation. Wattless charges can be eliminated by the installation of power factor correction capacitors. 

Waste heat

The unused heat produced from a process

Waste heat boiler

A boiler that receives energy input from the combustible exhaust gases from a separate fuel-burning process

Water softening

The treatment of water to reduce its level of lime. Hard water is water that contains greater levels of lime.

Wattage

The number of watts of power

Wattless Power

Power that is ?borrowed? from the load and returned to the power source each cycle. Also called 'reaactive' power

Weather compensation

A heating system control that adjusts the flow temperature in the system in response to changes in external temperatures. Overheating is prevented on mild days.

Winter Peak Demand Scheme

A scheme that offers electricity customers an opportunity to receive payment in return for committing to reducing their demand for electricity for specific hours during the winter months.

X

X-ray

A type of electromagnetic radiation having low energy levels

Xyloid Coal

Brown coal or lignite derived from wood

Xenon

Heavy gas used in specialized electric lamps

Y

No entries for letter Y

 Z

No entries for letter Z