Contents. 1 Introduction 2 2 Green Practices at Your Fingertips 3. 3 Reducing Radiant Heat 8. 4 Reducing Standby Power 9 5 Lighting 10

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3 Contents 1 Introduction 2 2 Green Practices at Your Fingertips Green Practices at Home 2.2 Green Practices at Office 3 Reducing Radiant Heat Window Film 3.2 Low-emissivity Glass 4 Reducing Standby Power 9 5 Lighting Luminaire 5.2 Control System 6 Motors and Drives Efficiency Motor 6.2 Variable Speed Drive 7 Air Conditioning Air Conditioner 7.2 Air Distribution for Central Air Conditioning System 8 Electricity Safety 16 9 Smart Power Centre 21 Smart Use of Electricity 1

4 1 Introduction HK Electric is committed to enhancing the environmental awareness of its business partners and educating the public on the smart and efficient use of energy. Electricity has become an everyday necessity. More and more 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 the market vary greatly in energy efficiency performance, 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 smart use of electricity and covers two major areas, namely, energy efficiency and electricity safety. 2 Introduction / Green Practices at Your Fingertips

5 Green Practices at Your Fingertips By implementing the following simple measures at no extra cost, you would be able to save money on the running costs, and at the same time, contribute to the conservation of our environment Green Practices at Home Lighting Turn off the lights whenever not in use Maximise the use of daylight Avoid over-lighting Keep lighting fixtures and lamps clean to maximise efficiency Air Conditioner Turn off the air conditioner whenever not in use Set room temperature to 25.5 C in summer Use ventilation fans instead of air conditioners whenever possible Clean the air filter regularly Close windows, doors and other openings whenever air conditioners are in use Avoid obstructing the air inlets and outlets Turn off unneeded lights and heat-producing appliances to reduce unnecessary loading of the air conditioner Avoid installing the air conditioner under direct sunlight Smart Use of Electricity 3

6 Dehumidifier Clean the air filter regularly to ensure effective performance Avoid obstructing the air inlet and outlet Close windows and doors whenever using dehumidifiers for better performance Computer and Audio-Visual Equipment Switch off the equipment whenever not in use Avoid leaving the equipment in standby mode Refrigerator Keep the refrigerator away from direct sunlight, oven or other heat sources Make sure the door seals properly. Avoid opening the door more than necessary Don t set the temperature excessively low Wrap food before storing in the refrigerator. Uncovered food releases moisture and make the compressor work harder Hot / warm food should be cooled down before storing in the refrigerator Defrost frozen food before cooking Cooker Keep pots and pans covered since water boils faster and food cooks faster in this manner Use the right pan for the right job. Foods will cook faster if you use pots and pans with flat bottoms and tight-fitting lids. Oversized or undersized pans waste energy 4 Green Practices at Your Fingertips

7 Washing Machine Use cold water cycle whenever possible and use less detergent Wait until you have a full-load before washing as a half load uses similar amount of energy Use a lower temperature setting or a shorter program whenever possible Tumble Dryer Whenever possible, dry your clean laundry outdoor Remove as much excess water as possible from your laundry before drying Sort laundry items and dry a full-load at a time Don t overload as this will block the airflow and greatly reduce drying efficiency Clean lint filter after use to improve air circulation Inspect dryer vent periodically to ensure no blockage Water Heater Switch off the heater after use Lower the thermostat setting in summer Use cold water wherever possible Iron Iron all items at one sitting to avoid reheating the iron Iron items that require the highest temperature setting first, then gradually scale down the temperature to suit other fabrics. At the end, residual heat might be considered for fabrics such as silk that requires lower temperature Smart Use of Electricity 5

8 2.2 Green Practices at Office Lighting Turn off the lights whenever not in use Affix Save Energy labels next to switches as reminders Maximise the use of daylight Avoid over-lighting Keep lighting fixtures and lamps clean to maximise efficiency Air Conditioning and Ventilation Turn off the air conditioning and ventilation whenever not in use Set room temperature to 25.5 C in summer Lower window blinds or curtains to reduce direct sunlight Set the air conditioning system to low fan speed as the normal setting. Use a high fan speed for increased cooling demand Use fans to increase air circulation Clean the air filter regularly Close windows, doors and other openings when the air conditioner is in use Avoid obstructing the air inlets and outlets Turn off unneeded lights and heat-producing appliances to reduce loading of the air conditioner Computer Turn off the computer whenever not in use Whenever not in use, set the computer to Sleep mode if it must be left on Reduce the brightness level of the screen to a lower yet comfortable level 6 Green Practices at Your Fingertips

9 Photocopier and Printer Turn off the photocopier and printer after office hours Schedule copying in batches to increase the length of time that the equipment can be left in standby or off mode Use power management or energy saving feature to reduce electricity consumption Fax Machine Use power management or energy saving feature to reduce electricity consumption Divert calls to one or two units after office hours and turn off the unused units Battery Chargers and Portable Transformers Unplug all equipment chargers and adapters whenever not in use Pantry Equipment Turn off the appliances whenever not in use Clean well-maintained equipment to enhance energy conservation Smart Use of Electricity 7

10 3 Reducing Radiant Heat Electromagnetic energy emitted from the sun may be broken down into spectrums of wavelengths. The three main spectrums are ultra violet, visible light and infrared energy. The invisible infrared is about 53% of the solar energy. It penetrates through glass windows and heats up the space. 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, solar heat gain through windows may take up 20% of the indoor air conditioning load of a building. Solar heat control glass and window film can effectively reduce solar heat gain while maintaining the transmission of visible light into the room. x-ray Solar Energy Ultra Violet Infrared Visible Light Microwave Visible Light Solar Heat Source Reflected Radiant Heat Solar Heat Control Glass or Window Film Details of the window film and glass: 3.1 Window Film Window film is generally retrofitted after a building is occupied. Being easy to install, the film can help reduce solar heat gain and help maintain a certain amount of visible light to come through the window. 3.2 Low-emissivity Glass Low-emissivity (Low-e) glass is coated with metallic materials such as titanium, silver, bronze, nickel, etc. It can reduce solar 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 hardcoated Low-e glass is slightly poorer than that of soft-coated Low-e glass. 8 Reducing Radiant Heat / Reducing Standby Power

11 Reducing Standby Power Standby power is the power consumed by an appliance under standby mode, i.e. the appliance will run in the lowest power consumption mode and is not performing their primary functions. Although this will provide some convenience to users, it also consumes a certain amount 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. 4 Standby Power 5 ~ 10% The following tips can help reduce the use of standby power: Purchase electrical appliances with energy labels Choose the appliances with low standby power Switch off those equipment immediately after use If the appliance will be idle for a prolonged period of time, switch off and unplug it from the power source. For appliances like computers, printers or scanners, switch them 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. Smart Use of Electricity 9

12 5 Lighting Lighting 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 can further save energy. 5.1 Luminaire The traditional incandescent lamp converts only 10% of the electrical energy into light while 90% of the energy is converted into heat. With the advance of technology, energy-efficient lighting equipment effectively reduces energy wastage but produces high luminosity. The operating principles and energy efficiency performance of some modern energy-efficient lighting equipment are: i. Fluorescent Lamps The ballast of a fluorescent lamp produces high voltage and 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 lamp is ionized after starting so the ballast can maintain the current at a lower voltage to sustain the discharge. T5 lamp has a smaller diameter (16mm) and an improved luminous efficacy up to 100 lm/w as compared to the conventional T8 lamp. When used with high frequency electronic ballasts, customers can enjoy up to 50% energy saving, lower maintenance 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 nanotechnology material. With the dimension and curvature properly designed, the jacket can reflect incident light to the surrounding with uniform distribution and illumination could be enhanced by 30% without additional energy consumption. 10 Lighting

13 Lamp Cover 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 which holds the ballast and the lamp can fit into an ordinary light-bulb socket. CFL can convert 40 to 50% of the input energy into light, i.e. around 4 times more efficient than an incandescent lamp. A 25 W CFL is as bright as a 100 W incandescent lamp. Phosphor coating Mercury vapor Argon Ballast Ballast housing For proper disposal of CFLs, please visit the Government s website Base iii. Light Emitting Diode (LED) LED lamp is a semiconductor diode supported by a reflector and encapsulated with an epoxy lens for controlling light distribution. For general purposes, it is necessary to rectify the AC supply to DC supply for operating LED. Unlike incandescent lamp that radiates a continuous spectrum, LED emits an almost monochromatic 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 than an incandescent lamp. Further, LED lamp also has the advantages of robustness and being extremely compact. molded epoxy lens anode lead cathode lead emitted light anode wire LED chip reflecting cup 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 efficiency than an ordinary fluorescent lamp. LED signages can substitute neon signages. By varying the composition of materials used in the semiconductor, different colour can be produced. LED is operated in DC voltage. A logic controller, is added to control the ON and OFF 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, robustness and high reliability as there is no oxidizing filament or breakable glass bulb. It is also capable of providing versatile color change, dimming and responding quickly to control commands. Smart Use of Electricity 11

14 5.2 Control System For greater energy saving in lighting, some lighting controls such as occupancy control and automatic lighting control may be considered. i. Occupancy Control Instead of switching off the lighting manually, occupancy sensors can automatically turn lights off in unoccupied spaces. Occupancy sensors can be installed based on usage pattern and can save up to 15% - 25% power consumption. Segment lens Source of heat Electronics Infrared sensor Light Signal amplifier Timer Photoelectric lighting controller Person, Animal, Car ii. Automatic Lighting Control Different activities need different levels of luminance. While most lighting systems have already been designed to certain desirable luminance levels, the actual luminance 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 controller will reduce the luminance output level. If the luminance level is lower than the default value, the luminance output level will be increased until the default value is reached. 12 Lighting / Motors and Drives

15 Motors and Drives Electric motors are the major prime movers of various mechanical systems such as air conditioning systems, water pumping systems and other industrial machines. Due to their wide applications, improvement in motor efficiency can certainly help reduce energy consumption Efficiency Motor Compared with conventional standard motors, high efficiency motors are designed to minimise loss when converting electrical energy into mechanical energy. According to IEC Energy Efficiency Classification, the motors can be classified as below: 6.2 Variable Speed Drive A variable speed drive (VSD) can be regarded as a frequency converter rectifying AC voltage from the mains supply into DC voltage, and then modifies this into AC voltage with variable amplitude and frequency to change continuously the speed of motors. It can be incorporated into an induction motor with a variable load. EFF3 EFF2 Pump and fan systems are usually sized to handle maximum load conditions, so that they might waste energy under part load conditions. Power is proportional to the cube of speed. When the motor speed is reduced to 50% of the rated value, the motor will consume only 12.5% of the maximum power. As such, the use of VSD to change the speed of motors under part load conditions is a cost-effective investment in raising energy efficiency. Smart Use of Electricity 13

16 7 Air Conditioning 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. Tips for Selecting an Air Conditioner: 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. Decide which category and features you would like to have: 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 Choose the right cooling capacity to suit the size of the premises. Excessive cooling capacity wastes energy. Approximate Indoor Floor Area Covered (m 2 ) Cooling Capacity Needed (kw) Below Choose an air conditioner with an energy label of higher grade to save energy. 14 Air Conditioning

17 7.2 Air Distribution for Central Air Conditioning System Constant Air Volume (CAV) System In a simple CAV system, the air flow rate is constant and the fan motors are running at full speed, leading to a waste in the fan power consumption under part load conditions. CAV VAV Variable Air Volume (VAV) System In a simple VAV system, the speed of motors is varied to deliver the required air flow and thus reduces the fan power consumption during part load conditions. To further reduce the fan power consumption under low load conditions, the static pressure reset control for VAV, which is an advanced control scheme, can save energy by lowering the static pressure set point of the supply air fan. Smart Use of Electricity 15

18 8 Electricity Safety Today, we enjoy modern living with different kinds of electrical appliances. However, if we do not pay attention to electrical safety, accidents may occur and can be costly. Here are some safety tips on the use of electricity: Television - Ensure enough space for ventilation - Avoid placing the television under direct sunlight or in a humid, dusty and hot environment Vacuum Cleaner - Don t use a vacuum cleaner to pick up water. Otherwise, it may cause leakage of electricity. Living Room 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 - If any abnormality (e.g. excessive noise, vibration or abnormal smell) is found, stop using and arrange for repair Plugs, Adaptors and Extension Units - Don t unplug an electrical appliance by pulling its flexible power cord - Replace the plug if its enclosure is broken and with exposed conductive parts - Don t buy or use any adaptors or extension units with irregular holes or without safety shutter - Only buy and use plugs, adaptors and extension units which comply with the safety requirements - Don t touch electrical appliances, sockets or switches with wet hands 16 Electricity Safety

19 Air Conditioner - To prevent damage, don t switch it on and off repeatedly within 3 minutes - Ensure that the air inlets and outlets are not obstructed - If there is abnormality (e.g. excessive noise, vibration or abnormal smell), stop using and arrange for repair Lighting - Don t place curtains, rugs, clothes, etc. close to lighting fixtures to prevent fire - Don t use light bulbs with power rating exceeding that of the lamp holder to avoid overheating Bedroom Personal Computer - Ensure enough space for ventilation to prevent overheating and don t cover them with any objects Mobile Charger - Keep the contacts of charger away from any metallic part to avoid the risks of short-circuit and fire - Don t use the charger when it becomes excessively hot Smart Use of Electricity 17

20 Electric Oven - When in use, don t leave it unattended - Use safety locks if it is within children s reach Microwave Oven - Don t cook eggs with a microwave oven - Don t use metallic container in a microwave oven - Use safety locks if it is within children s reach Kitchen Electric Kettle - Don t immerse the kettle into water when cleaning - Dry it out before connecting the supply - Don t add too much water into the kettle Refrigerator - Ensure enough space for ventilation and keep the refrigerator away from direct sunlight 18 Electricity Safety

21 Bathroom Electric Water Heater - Don t install any on/off control valve on 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 t overload the washing machine - Clean the drainage system regularly and prevent it from overheating Smart Use of Electricity 19

22 How to Handle Supply Interruption Apart from the above safety tips, you may also wish to know how to handle supply interruption. Here are some simple guidelines. Scenario 1 : If only your flat has lost supply a Check the main Miniature Circuit Breaker (MCB) and/or Residual Current Device (RCD) in the electrical distribution board. If it has tripped, the interruption may have been caused by defective appliances, wiring or overloading in your flat. b Identify and isolate the defective appliances or circuit that has caused the tripping. c Try to reset the MCB or RCD to ON position to restore supply. If MCB or RCD cannot be reset to ON position, call a Registered Electrical Contractor to check and repair. DON T attempt to repair faulty equipment or carry out any work on the wiring by yourself. Scenario 2 : If only your floor or only part of your building has lost supply, the interruption may be caused by the building s communal installation. Call your management office to follow up. Scenario 3 : If the whole building has lost supply, call our Customer Emergency Services Centre at Electricity Safety / Smart Power Centre

23 Smart Power Centre 9 To promote energy saving and environmental care, HK Electric has set up a Smart Power Centre at Electric Centre in North Point for customers to learn more about the smart and efficient use of electricity. Adopting an interactive approach to promote a low carbon lifestyle, the Smart Power Centre is designed to demonstrate various energy-efficient electrical equipment / appliances and introduce tips on the safe and efficient use of electricity. Customers, electrical contractors / workers and property management companies are welcome to visit the Centre. Guided tours can be arranged on request. Please call for details. Disclaimer The contents in this booklet are general guidelines only. In case of doubt, you should seek advice from an expert or a professional engineer. The Hongkong Electric Co., Ltd. shall not 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. Smart Use of Electricity 21

24 Printed on Recycled Paper 2013