1Smart Use of Electricity

1 Introduction 2

2 Green Practices at Your Fingertips 3 2.1 Green Practices at Home

2.2 GreenPracticesatOffice

3 Reducing Radiant Heat 8 3.1 Window Film

3.2 Low-emissivity Glass

4 Reducing Standby Power 9

5 Lighting 10 5.1 Luminaire

5.2 Control System

6 Motors and Drives 13 6.1 EfficiencyMotor

6.2 Variable Speed Drive

7 Air Conditioning 14 7.1 Air Conditioner

7.2 Air Distribution for Central Air Conditioning System

8 Electricity Safety 16

9 Smart Power Centre 21

Contents

2 Introduction / Green Practices at Your Fingertips

HK Electric is committed to enhancing the environmental awareness of its business partners and educating the publiconthesmartandefficientuseofenergy.

Electricityhasbecomeaneverydaynecessity.Moreandmore electrical appliances are being used in business and at home for better productivity and quality of life. Since different types / models of electrical appliances available in themarketvarygreatlyinenergyefficiencyperformance,you are encouraged to select wisely the ones that meet your requirements and use electricity smartly.

This brochure aims to help you understand more about the smartuseofelectricityandcoverstwomajorareas,namely,energyefficiencyandelectricitysafety.

Introduction1

3Smart Use of Electricity

Byimplementingthefollowingsimplemeasuresatnoextracost,youwouldbeabletosavemoneyontherunningcosts,andatthesametime,contributetotheconservationofourenvironment.

2.1 Green Practices at Home

Lighting

• Turnoffthelightswhenevernotinuse

• Maximisetheuseofdaylight

• Avoidover-lighting

• Keeplightingfixturesandlampscleantomaximiseefficiency

2Green Practices at Your Fingertips

Air Conditioner

• Turnofftheairconditionerwhenevernotinuse

• Setroomtemperatureto25.5°Cinsummer

• Useventilationfansinsteadofairconditioners whenever possible

• Cleantheairfilterregularly

• Closewindows,doorsandotheropeningswheneverairconditioners are in use

• Avoidobstructingtheairinletsandoutlets

• Turnoffunneededlightsandheat-producingappliancestoreduce unnecessary loading of the air conditioner

• Avoidinstallingtheairconditionerunderdirectsunlight

4 Green Practices at Your Fingertips

Dehumidifier

• Cleantheairfilterregularlytoensureeffectiveperformance

• Avoidobstructingtheairinletandoutlet

• Closewindowsanddoorswheneverusingdehumidifiersforbetter performance

Computer and Audio-Visual Equipment

• Switchofftheequipmentwhenevernotinuse

• Avoidleavingtheequipmentinstandbymode

Refrigerator

• Keeptherefrigeratorawayfromdirectsunlight,ovenorotherheatsources

• Make sure the door seals properly. Avoid opening the doormorethan necessary

• Don’tsetthetemperatureexcessivelylow

• Wrapfoodbeforestoringintherefrigerator.Uncoveredfoodreleasesmoisture and make the compressor work harder

• Hot / warm food should be cooled down before storing in therefrigerator

Cooker

• Defrostfrozenfoodbeforecooking

• Keeppotsandpanscoveredsincewaterboils faster and food cooks faster in this manner

• Usetherightpanfortheright job.Foodswillcookfaster ifyouusepotsandpanswithflatbottomsandtight-fittinglids.Oversizedorundersizedpanswasteenergy

5Smart Use of Electricity

WashingMachine

• Usecoldwatercyclewheneverpossibleanduse less detergent

• Waituntilyouhaveafull-loadbeforewashingasahalfload uses similar amount of energy

• Usealowertemperaturesettingorashorterprogramwhenever possible

Tumble Dryer

• Wheneverpossible,dryyourcleanlaundryoutdoor

• Removeasmuchexcesswateraspossiblefromyourlaundrybeforedrying

• Sortlaundryitemsanddryafull-loadatatime

• Don’toverloadasthiswillblocktheairflowandgreatlyreducedryingefficiency

• Cleanlintfilterafterusetoimproveaircirculation

• Inspectdryerventperiodicallytoensurenoblockage

Water Heater

• Switchofftheheaterafteruse

• Lowerthethermostatsettinginsummer

• Usecoldwaterwhereverpossible

Iron

• Ironallitemsatonesittingtoavoidreheatingtheiron

• Iron items that require the highest temperature setting first, thengradually scale down the temperature to suit other fabrics. At the end,residualheatmightbeconsideredforfabricssuchassilkthatrequires lower temperature

6 Green Practices at Your Fingertips

2.2 GreenPracticesatOffice

Lighting

• Turnoffthelightswhenevernotinuse

• Affix‘SaveEnergy’labelsnexttoswitchesasreminders

• Maximisetheuseofdaylight

• Avoidover-lighting

• Keeplightingfixturesandlampscleantomaximiseefficiency

Air Conditioning and Ventilation

• Turnofftheairconditioningandventilationwhenevernot in use

• Setroomtemperatureto25.5°Cinsummer

• Lowerwindowblindsorcurtainstoreducedirectsunlight

• Settheairconditioningsystemtolowfanspeedasthenormalsetting. Use a high fan speed for increased cooling demand

• Usefanstoincreaseaircirculation

• Cleantheairfilterregularly

• Closewindows,doorsandotheropeningswhentheairconditionerisinuse

• Avoidobstructingtheairinletsandoutlets

• Turnoffunneededlightsandheat-producingappliancestoreduce loading of the air conditioner

Computer

• Turnoffthecomputerwhenevernotinuse

• Whenevernotinuse,setthecomputerto‘Sleep’modeifitmustbe left on

• Reducethebrightnesslevelofthescreentoaloweryetcomfortable level

7Smart Use of Electricity

Photocopier and Printer

• Turnoffthephotocopierandprinterafterofficehours

• Schedulecopyinginbatchestoincreasethelengthoftime that the equipment can be left in standby or off mode

• Use‘powermanagement’or‘energysaving’featuretoreduceelectricity consumption

FaxMachine

• Use‘powermanagement’or‘energysaving’featuretoreduceelectricity consumption

• Divertcallstooneortwounitsafterofficehoursandturnofftheunused units

Battery Chargers and Portable Transformers

• Unplugallequipmentchargersandadapters whenever not in use

Pantry Equipment

• Turnofftheapplianceswhenevernotinuse

• Cleanwell-maintainedequipmenttoenhanceenergyconservation

8 Reducing Radiant Heat / Reducing Standby Power

Electromagnetic energy emitted from the sun may be broken down into spectrums of wavelengths. The three main spectrums are ultra violet,visiblelightandinfraredenergy.Theinvisibleinfraredisabout53% of the solar energy. It penetrates through glass windows and heats up the space.

Reducing Radiant Heat3

Solar heat gain is one of the heat sources in an air-conditioned space and reducing solar heat gain can save energy for the air conditioning equipment. In general, solarheat gain through windows may take up 20% of the indoor air conditioning load of a building. Solar heat control glass and windowfilmcaneffectivelyreducesolarheatgain while maintaining the transmission of visible light into the room.

Detailsofthewindowfilmandglass:

3.1 Window FilmWindow film is generally retrofitted after abuilding is occupied.Beingeasy to install,thefilmcanhelpreducesolarheatgainandhelp maintain a certain amount of visible light to come through the window.

3.2 Low-emissivity GlassLow-emissivity (Low-e) glass is coated with metallic materials such as titanium,silver, bronze, nickel, etc. It can reducesolar heat gain and allow highly visible light transmission. Low-e glass is either soft or hard coated. The hard-coated Low-e glass is more durable than the soft-coated glass while the energy performance of hard-coated Low-e glass is slightly poorer than that of soft-coated Low-e glass.

Solar Energyx-ray

Ultra VioletVisible Light

InfraredMicrowave

Solar Heat Source

ReflectedRadiantHeatSolar Heat Control Glass

or Window Film

Visible Light

9Smart Use of Electricity

4Reducing Standby Power

Thefollowingtipscanhelpreducetheuseofstandbypower:

• Purchaseelectricalapplianceswithenergylabels

• Choosetheapplianceswithlowstandbypower

• Switchoffthoseequipmentimmediatelyafteruse

• If the appliance will be idle for a prolonged period oftime,switchoffandunplugit fromthepowersource.Forappliances like computers, printers or scanners, switchthem off directly after use.

An effective solution for reducing the standby power of AV and computer equipment is to use an intelligent panel/adaptor to turn off the appliances and its peripherals automatically.

Standby power is the power consumed by an appliance under standby mode, i.e. theappliancewill run in the lowestpowerconsumptionmode and is not performing their primary functions. Although this willprovidesomeconveniencetousers,italsoconsumesacertainamount of energy. The standby power is usually 0.5W - 10W but could be up to 15W - 25W. It could even account for around 5 - 10% of total power consumption of an electrical appliance.

Standby Power5 ~ 10%

10 Lighting

T5 lamp has a smaller diameter (16mm) and an improved luminous efficacy up to 100 lm/W as compared to theconventional T8 lamp. When used with high frequency electronicballasts,customerscanenjoyupto50%energysaving, lowermaintenance costs, increased system’s life,and improved quality of light.

Illumination level can be further increased with the use of luminosity enhancement jacket made of nano-technology material. With the dimension and curvature properly designed, the jacket can reflect incident light tothe surrounding with uniform distribution and illumination could be enhanced by 30% without additional energy consumption.

i. Fluorescent LampsTheballastofafluorescent lampproduceshighvoltageand an electric discharge which in turn excites the mercury vapour inside the lamp to produce ultraviolet light. The ultraviolet light then hits on the phosphor coating on the glass to produce visible light. The gas inside the lampis ionizedafterstartingsotheballastcanmaintainthe current at a lower voltage to sustain the discharge.

The traditional incandescent lamp converts only 10% of the electrical energy into light while 90% of the energy is converted intoheat.Withtheadvanceoftechnology,energy-efficientlightingequipment effectively reduces energy wastage but produces high luminosity. The operating principles and energy efficiency performance of some modern energy-efficient lighting equipment are:

Lighting5Lighting constitutes an average of 20% and 30% of the total electricity consumption of domestic and commercial customers respectively. Apart from the green practices for lighting suggested in Chapter 2, there are various energy-efficient lighting equipment which canfurther save energy.

5.1 Luminaire

11Smart Use of Electricity

iii. Light Emitting Diode (LED) LED lamp is a semiconductor diode supported by a reflector and encapsulated with an epoxy lens forcontrollinglightdistribution.Forgeneralpurposes,itis necessary to rectify the AC supply to DC supply for operating LED. Unlike incandescent lamp that radiatesacontinuousspectrum,LEDemitsanalmostmonochromatic light of a particular colour which depends on the material used. LED is an emitting luminescence and no energy is wasted to generate unwanted heat so it is more energy efficient thanan incandescent lamp. Further, LED lamp also hasthe advantages of robustness and being extremely compact.

LED signages can substitute neon signages. By varying thecompositionofmaterialsusedinthesemiconductor,different colour can be produced. LED is operated in DC voltage.Alogiccontroller,isaddedtocontroltheONandOFF of the independent groups of LED and thus provides the animation effects. The advantages of LED signage are long life span of up to 50,000 hours, robustnessand high reliability as there is no oxidizing filament orbreakable glass bulb. It is also capable of providing versatilecolorchange,dimmingandrespondingquicklyto control commands.

LED tube is formed by many small LED units which are connected in both series and parallel. The tube is driven by DC power so the tube will need internal circuits to operate from AC voltage and heat management element such as heat sink. LED tube can offer longer service life and higher energy efficiencythananordinaryfluorescentlamp.

ii. Compact Fluorescent Lamp (CFL)The working principle of a compact fluorescent lamp(CFL) is the same as a common fluorescent lamp.Its bending glass tube is affixed onto a base whichholds theballastand the lampcanfit intoanordinary light-bulb socket. CFL can convert 40 to 50% of the input energyintolight,i.e.around4timesmoreefficientthanan incandescent lamp. A 25 W CFL is as bright as a 100 W incandescent lamp.

ForproperdisposalofCFLs,pleasevisittheGovernment’swebsitewww.wastereduction.gov.hk.

LED chip

reflecting cup

anode lead

molded epoxy lens

cathode lead

emitted light

anode wire

Cover

Phosphor coating

Mercury vapor

Argon

Ballast

Ballast housing

Base

Lamp

12 Lighting/MotorsandDrives

i. Occupancy ControlInsteadofswitchingoffthelightingmanually,occupancysensorscanautomaticallyturn lights off in unoccupied spaces. Occupancy sensors can be installed based on usage pattern and can save up to 15% - 25% power consumption.

ii. Automatic Lighting ControlDifferent activities need different levels of luminance. While most lighting systems have already been designed to certain desirable luminance levels, the actualluminance levels when in use may be different. Automatic lighting control helps maintain the indoor luminance level at an optimal level while preventing energy waste. If the luminance level is higher than the default value, the controllerwillreduce the luminance output level. If the luminance level is lower than the default value,theluminanceoutputlevelwillbeincreaseduntilthedefaultvalueisreached.

5.2 Control SystemForgreaterenergysaving in lighting,some lightingcontrolssuchasoccupancycontrol and automatic lighting control may be considered.

Light Signal amplifierTimerPhotoelectric lighting controller

Segment lens

Infraredsensor

Electronics

Person, Animal, Car

Source of heat

13Smart Use of Electricity

6.2 Variable Speed DriveA variable speed drive (VSD) can be regarded as a frequency converter rectifyingACvoltage fromthemainssupply intoDCvoltage,and thenmodifies this intoACvoltagewithvariableamplitudeand frequency tochange continuously the speed of motors. It can be incorporated into an induction motor with a variable load.

Pumpand fansystemsareusually sizedto handle maximum load conditions, sothat they might waste energy under part load conditions. Power is proportional to the cube of speed. When the motor speed isreducedto50%oftheratedvalue,themotor will consume only 12.5% of the maximumpower.Assuch,theuseofVSDto change the speed of motors under part load conditions is a cost-effective investmentinraisingenergyefficiency.

6MotorsandDrivesElectric motors are the major prime movers of various mechanical systemssuchasairconditioningsystems,waterpumpingsystemsand other industrial machines. Due to their wide applications,improvement inmotor efficiency can certainly help reduce energyconsumption.

6.1EfficiencyMotorCompared with conventional standard motors,highefficiencymotorsaredesigned tominimiseloss when converting electrical energy into mechanical energy. According to IEC 60034 Energy Efficiency Classification, the motors canbeclassifiedasbelow:

EFF3EFF2

14 Air Conditioning

Air Conditioning7

TipsforSelectinganAirConditioner:

• Chooseanairconditionerwithanenergylabelofhighergradetosaveenergy.

7.1 Air Conditioner

Window Type Air Conditioner

A window unit is a self-contained packaged air conditioner. All components are housed within the unit. It is installed through an opening in the wall and no inter-piping connection is required.

Split Type Air Conditioner

A split unit comprises two parts - the outdoor Condensing Unit (CDU) and the indoor Fan Coil Unit (FCU). The CDU consists of a compressor and a heat rejecting condenser coil. The FCU is a cooling coil. Interconnecting piping between CDU and FCU is required to run this system.

• Decidewhichcategoryandfeaturesyouwouldliketohave:

Category Description 1 A window type air conditioner with cooling function only

2 A window type air conditioner with cooling and heating functions

3 A split type air conditioner with cooling function only

4 A split type air conditioner with both cooling function and heating function

• Choosetherightcoolingcapacitytosuitthesizeofthepremises.Excessivecoolingcapacity wastes energy.

Approximate Indoor Floor Area Covered (m2) Cooling Capacity Needed (kW) Below 7.5 2.05

7.5 – 12.0 2.64

12.0 – 23.0 3.52

23.0 – 35.0 5.27

15Smart Use of Electricity

7.2 Air Distribution for Central Air Conditioning System

Constant Air Volume (CAV) System

InasimpleCAVsystem,theairflowrateisconstantandthefanmotorsarerunningatfullspeed,leadingtoawastein the fan power consumption under part load conditions.

Variable Air Volume (VAV) System

In a simpleVAVsystem, the speedofmotors is varied todeliver therequiredairflowandthusreducesthefanpowerconsumptionduringpart load conditions.

Tofurtherreducethefanpowerconsumptionunderlowloadconditions,thestaticpressureresetcontrolforVAV,whichisanadvancedcontrolscheme,cansaveenergyby loweringthestaticpressuresetpointofthe supply air fan.

CAV

VAV

16 Electricity Safety

Electricity Safety8Today, we enjoy modern living with different kinds of electricalappliances.However, ifwedonotpayattentiontoelectricalsafety,accidents may occur and can be costly. Here are some safety tips on theuseofelectricity:

Living Room

Plugs, Adaptors and Extension Units- Don’tunpluganelectricalappliancebypullingitsflexiblepowercord

- Replace the plug if its enclosure is broken and with exposed conductive parts

- Don’tbuyoruseanyadaptorsorextensionunits with irregular holes or without safety shutter

- Onlybuyanduseplugs,adaptorsandextension units which comply with the safety requirements

- Don’ttouchelectricalappliances,socketsorswitches with wet hands

Electric Fan- Clean the fan regularly. Excessive dust on the

fan motor may prevent heat dissipation- Ensure enough space for its operation- Prevent sticking the blades- Ifanyabnormality(e.g.excessivenoise,vibrationorabnormalsmell)isfound,stopusing and arrange for repair

Television- Ensure enough space for ventilation- Avoid placing the television under direct sunlight orinahumid,dustyandhotenvironment

Vacuum Cleaner- Don’tuseavacuumcleanertopickupwater.Otherwise,itmaycauseleakageof electricity.

17Smart Use of Electricity

Bedroom

Air Conditioner- Topreventdamage,don’tswitchitonand

off repeatedly within 3 minutes- Ensure that the air inlets and outlets are

not obstructed- If there is abnormality (e.g. excessive noise,vibrationorabnormalsmell),stopusing and arrange for repair

Personal Computer- Ensure enough space for ventilation to preventoverheatinganddon’tcoverthem with any objects

Lighting- Don’tplacecurtains,rugs,clothes,etc.closetolightingfixturestopreventfire

- Don’tuselightbulbswithpowerratingexceeding that of the lamp holder to avoid overheating

Mobile Charger- Keep the contacts of charger away from

any metallic part to avoid the risks of short-circuitandfire

- Don’tusethechargerwhenitbecomesexcessively hot

18 Electricity Safety

Kitchen

Electric Oven- Wheninuse,don’tleaveitunattended- Usesafetylocksifitiswithinchildren’s

reach

Electric Kettle- Don’timmersethekettleintowater

when cleaning- Dry it out before connecting the supply- Don’taddtoomuchwaterintothekettle

Microwave Oven- Don’tcookeggswithamicrowaveoven- Don’tusemetalliccontainerina

microwave oven- Usesafetylocksifitiswithinchildren’s

reach

Refrigerator- Ensure enough space for ventilation

and keep the refrigerator away from direct sunlight

19Smart Use of Electricity

Bathroom

Electric Water Heater- Don’tinstallanyon/offcontrolvalveon

the outlet of a shower type water heater. It will build up pressure inside the heater and cause explosion.

Washing Machine- Ensure enough space for ventilation- Don’toverloadthewashingmachine- Clean the drainage system regularly

and prevent it from overheating

20 Electricity Safety / Smart Power Centre

a

cTrytoresettheMCBorRCDto‘ON’positionto restore supply. IfMCB or RCD cannotberesetto‘ON’position,callaRegisteredElectrical Contractor to check and repair. DON’Tattempt to repair faultyequipmentor carry out any work on the wiring by yourself.

Scenario 2 : If only your floor or only part of yourbuilding has lost supply, the interruptionmaybecausedbythebuilding’scommunalinstallation.Callyourmanagementofficetofollow up.

Scenario 3 : If the whole building has lost supply, callour Customer Emergency Services Centre at 2555 4000.

bIdentify and isolate the defective appliances or circuit that has caused the tripping.

Check the main Miniature Circuit Breaker(MCB) and/orResidualCurrentDevice (RCD)in the electrical distribution board. If it has tripped,theinterruptionmayhavebeencausedbydefectiveappliances,wiringoroverloadinginyourflat.

Scenario 1 : Ifonlyyourflathaslostsupply

Apartfromtheabovesafetytips,youmayalsowishtoknowhowtohandlesupplyinterruption. Here are some simple guidelines.

How to Handle Supply Interruption

21Smart Use of Electricity

Topromoteenergysavingandenvironmentalcare,HKElectrichassetupaSmartPowerCentreatElectricCentre inNorthPointforcustomerstolearnmoreaboutthesmartandefficientuse of electricity.

Adopting an interactive approach to promote a low carbon lifestyle, theSmartPowerCentre isdesignedtodemonstratevariousenergy-efficientelectricalequipment/appliancesandintroducetipsonthesafeandefficientuseofelectricity.

Customers, electrical contractors / workers and propertymanagement companies are welcome to visit the Centre. Guided tours can be arranged on request. Please call 2887 3455 for details.

Disclaimer

Thecontentsinthisbookletaregeneralguidelinesonly.Incaseofdoubt,youshouldseekadvicefromanexpertoraprofessionalengineer.TheHongkongElectricCo.,Ltd.shallnot be liable for any loss and damage suffered by any persons howsoever arising from or in reliance upon the whole or part of the contents of this booklet.

9Smart Power Centre

Printed on Recycled Paper 2013