ENERGY EFFICIENCY GUIDELINES FOR STREET LIGHTING IN THE PACIFIC

Transcription

1 ENERGY EFFICIENCY GUIDELINES FOR STREET LIGHTING IN THE PACIFIC Promoting Energy Efficiency in the Pacific (Phase 2)

2 2015 International Institute for Energy Conservation (IIEC) Energy Efficiency Guidelines for Street Lighting in the Pacific International Institute for Energy Conservation (IIEC) 12 th Floor, UBC II Building, Suite Sukhumvit Rd,(Corner Soi 33) Wattana,Bangkok 10110,Thailand Tel : Fax : Published by: International Institute for Energy Conservation (IIEC) Photos Title Page: Photograph Courtesy of All-free-download at all-free-download.com/free-photos/night_traffic_ html Design: International Institute for Energy Conservation (IIEC) Produced under: Promoting Energy Efficiency in the Pacific Phase 2 With funding support of: Asian Development Bank (ADB) Acknowledgement: This document has been produced with the financial assistance of the Asian Development Bank. The contents of this document are the sole responsibility of International Institute for Energy Conservation and can under no circumstances be regarded as reflecting the position of the Asian Development Bank.

3 ENERGY EFFICIENCY GUIDELINES FOR STREET LIGHTING IN THE PACIFIC

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5 CONTENTS 1 INTRODUCTION Objectives of the Guidelines About the Guidelines Who Should Read these Guidelines? Other Energy Efficiency Guidelines 2 2 OVERVIEW OF STREET LIGHTING 2.1 Purpose of Street Lighting 2.2 Basic Lighting Terms 2.3 Standards, Regulations and Recommendations for Street Lighting 3 COMPONENTS OF STREET LIGHTING 3.1 Optical Systems Lamps Control Gears Luminaire Photoelectric Controls 3.2 Structural Systems Poles Mast Arms (Mounting Brackets) Bases and Foundations 3.3 Electrical Systems Grounding Voltage Drop Energy Metering Service Cabinets 4 DESIGNING AN ENERGY EFFICIENT STREET LIGHTING PROJECT 4.1 Understanding Roadway Categories and Lighting Recommendations Classifying Roadways by Category Understanding Lighting Quality Recommendations Determining Actions Retrofits or New Systems 4.2 Shortlisting the Appropriate Lighting Technologies Advantages of LEDs and HPS Lamps A Quick Selection Guide for Replacing FLs and MVs with LED and HPS Lamps (for Retrofit Projects) 4.3 Simulating Lighting Design and Calculating Costs Design Components to Consider Simulating Lighting Design with Computer Programs Conducting a Life Cycle Cost Analysis (LCCA) Calculating Financial Payback Periods 4.4 Measuring and Calculating Average Illuminance Contents

6 5 MAINTENANCE OF EE STREET LIGHTING 5.1 Cleaning Luminaires 5.2 Lamp Replacement 5.3 Electrical Wiring Inspection 5.4 Measurement of Voltage Input 6 APPENDIX 1: LIGHTING TERMINOLOGIES AND BASIC UNITS 7 APPENDIX 2: LAMP REQUIREMENTS AND SAMPLE TECHNICAL SPECIFICATIONS 7.1 HPS Luminaire Requirements 7.2 LED Luminaire Requirements 8 APPENDIX 3: SAMPLE OF LIGHTING MEASUREMENT SHEET APPENDIX 4: LCCA ALTERNATE FORMULA REPRESENTATION, AND EXAMPLE BIBLIOGRAPHY 46 Contents

7 FIGURES Figure 3-1 Figure 3-2 Figure 3-3 Figure 3-4 Figure 3-5 Figure 3-6 Figure 3-7 Figure 3-8 Figure 3-9 Figure 3-10 Figure 3-11 Figure 3-12 Figure 3-13 Figure 3-14 Figure 3-15 Figure 3-16 Figure 3-17 Figure 3-18 Figure 3-19 Figure 3-20 Figure 3-21 Figure 3-22 Figure 3-23 Figure 3-24 Figure 3-25 Figure 3-26 Figure 3-27 Figure 4-1 Figure 4-2 Figure 4-3 Figure 4-4 Figure 5-1 Figure 8-1 Figure 9-1 Typical HID Lamp and Control Gear Circuit 7 Typical LED Array and Driver Circuit 7 Cobra Head Style Luminaires 8 High Mast Style Luminaires 8 Vertical Mount Style Luminaire 9 Shoebox Style Luminaires 9 LED Style Luminaire 9 Basic Functions of Reflector, Refractor and Lens in Street Lighting Luminaires 10 Reflectors used in HID and LED Luminaires 10 Refractor of a Cobra Type HID Luminaire 10 How LED Lenses Control Light Distribution 11 Cutoff Characteristics Full Cutoff 11 Cutoff Characteristics Cutoff 12 Cutoff Characteristics Semi-cutoff 12 Cutoff Characteristics Non-cutoff 12 IESNA Lateral Light Distribution Classification Types 13 Ingress Protection (IP) 14 Mechanical or Impact Protection 15 Internal and External Installation of Photoelectric Control 16 Single-sided Configuration 17 Staggered Configuration 17 Opposite Configuration 18 Twin Central Configuration 18 Mast Arms (Mounting Brackets) 19 Base and Foundation for Lighting Pole 19 Pad Mounted Service Cabinet 21 Pole Mounted Service Cabinet 21 Designing an Energy Efficient Street Lighting Project Flowchart 23 Geometry of Street Lighting 28 Illustration of Illuminance Field of Calculation and Measurement 31 Calculation of Lighting Quality Parameters using an Excel Spread Sheet 33 Comparison of Lamp Replacement Frequency of HID Lamp and LED 35 Sample of Lighting Measurement Sheet 42 Example of LCCA between 100 sets of MV and LED Street Lighting Systems 45 Figures

8 TABLES Table 2-1 Table 3-1 Table 4-1 Table 4-2 Table 4-3 Table 7-1 Table 7-2 Table 9-1 Lighting Terminologies and Basic Units 4 Types of Lamp Technologies 6 Recommended Illumination Level for Different Classification of Roads 25 Recommended HPS Lamp Wattage and LED Luminaire for EE Retrofits 27 Lighting Design Software Tools 29 HPS Luminaire Requirements 38 LED Luminaire Requirements 40 Life Cycle Cost Analysis, Mercury Vapor Luminaire vs. LED Luminaires 44 Tables

9 ADB CCT Cd CDM CIE CRI E EE GEF GHG HID HPS IEC IIEC IESNA IK IP J kwh L LCCA LED LLD Lux lm MH MV PDMCs PEEP2 PNG RETA U 0 U 1 UNFCCC USD UV W Asian Development Bank Correlated Color Temperature Candela Clean Development Mechanism Commission Internationale de L Eclairage Color Rendering Index Illuminance/ Illumination Energy Efficiency Global Environment Facility Greenhouse Gas High-Intensity Discharge High-Pressure Sodium International Electrotechnical Commission International Institute for Energy Conservation Illuminating Engineering Society of North America Mechanical Protection [from Impact] Ingress Protection Joules Kilo Watt Hours Luminance Life Cycle Cost Analysis Light Emitting Diode Lamp Lumen Distribution Luminous Flux Per Unit Area Lumen Metal Halide Mercury Vapor Pacific Developing Member Countries Promoting Energy Efficiency in the Pacific Phase 2 Papua New Guinea Regional Technical Assistance Overall uniformity of Luminance Uniformity of Luminance United Nations Framework Convention on Climate Change United States dollar Ultra Violet Watt ACRONYMS Acronyms

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11 1 INTRODUCTION 1.1 Objectives of the Guidelines Based on a consultation process conducted in 2007 on behalf of the Global Environment Facility (GEF) Pacific Alliance for Sustainability, five Pacific Developing Member Countries (PDMCs) the Cook Islands, Papua New Guinea (PNG), Samoa, Tonga, and Vanuatu assigned high priority to reducing their use of fossil fuel. In response, the Asian Development Bank (ADB) approved Regional Technical Assistance (RETA) for promoting energy efficiency in the Pacific in September This project was implemented in 2 phases. The first phase concluded in May 2011, and focused on identifying a pipeline of specific energy efficiency projects for funding and co-financing by ADB, GEF, and other sources. The objective of the second phase Promoting Energy Efficiency in the Pacific (PEEP2) was to improve the efficiency of electrical power for end-users in the residential, commercial, and government sectors across the 5 PDMCs. This goal was addressed with several complementary methods: building stakeholder knowledge, mainstreaming government policies, implementing energy in new and existing buildings, and disseminating information to build awareness and change behavior. These actions resulted in: enhanced energy security, reduced energy costs for end-users, and overall reductions in greenhouse gas (GHG) emissions. The Energy Efficiency Guidelines for Street Lighting in the Pacific were developed under PEEP2 in order to help achieve energy and financial savings, while increasing public safety for drivers and pedestrians. The guidelines help achieve these goals by providing methods and techniques for enhancing efficiency and quality of street and public lighting in the Pacific. 1.2 About the Guidelines The Energy Efficiency Guidelines for Street Lighting in the Pacific were designed in accordance with the specific needs and requirements of the PDMCs, which have limited resources due to their geographical placement. The utilities, public and private sectors have limited experience in developing and implementing energy efficiency projects capable of making considerable impact in the region. These guidelines were designed taking the above factors into consideration, and are intended to significantly reduce costs, save energy, and lower GHG emissions. These guidelines employ a simple and effective approach for achieving such reductions; they provide guidance on how utility and municipal staff can improve the energy efficiency and performance of street and public lighting. They also provide methods for reducing the operation and maintenance cost of public lighting in order to ensure on-going quality and functionality. These guidelines provide a range of easy to follow techniques and methodologies on the different steps in design, installation and maintenance of energy efficient street lighting in the Pacific. Introduction

12 1.3 Who Should Read these Guidelines? The Energy Efficiency Guidelines for Street Lighting in the Pacific are developed for utilities and municipalities in the Pacific. This document will be particularly helpful for: 1.4 Other Energy Efficiency Guidelines Energy Efficiency Guidelines for Hotels, Commercial, and Public Buildings in the Pacific are also available. To receive a digital copy, please contact IIEC or visit Introduction

13 2 OVERVIEW OF STREET LIGHTING 2.1 Purpose of Street Lighting Street Lighting (or Roadway Lighting) is one of the most common forms of exterior lighting 1. The general purpose and importance of street lighting is to allow drivers and pedestrians to travel safely, see hazards, recognize objects and have a sense of security, as a result of improved night time visibility. Properly designed and maintained street lighting can provide comfort and safety during nighttime conditions for both vehicle and pedestrian traffic. In fact, street lighting does more than just reduce nighttime traffic accidents, and it can also: Reduce the level of petty crime and personal robbery, and give citizens a better feeling of security; Help road users without head lamps (e.g. the non-motorized, two-wheelers, etc.) to see potholes and small obstacles; On multi-purpose roads, it can enhance commercial and social activity during the hours of darkness, particularly after dusk; small installations in village centers, even operating for a few hours, can enhance community life; Make urban centers more attractive, especially for visitors and tourists. Some of the major issues concerning the design and specifications for roadway lighting include the light level, colour quality, light distribution, maintenance and initial cost. In recent years, energy efficiency has also become a priority consideration particularly in countries where electricity tariffs are high due to the long operating hours of most outdoor lights. Increased energy efficiency in street lighting systems significantly reduces operation and maintenance costs. Through cost-effective energy efficiency measures, energy and monetary savings of 20%- 50% can be achieved. The initial investment cost associated with more efficient lighting technologies is easily outweighed by the lower overall life-cycle costs 2 of efficient lighting. 2.2 Basic Lighting Terms Important lighting terminologies and basic units are summarized in Table 2-1. Detailed descriptions are given in Appendix 1. 1 Other exterior lighting applications include landscape, building facades, monuments, and signage, retail and commercial establishments 2 A life-cycle cost is defined as a sum of an initial purchasing price of equipment, installation costs, as well as maintenance and energy costs incurred throughout the equipment life time. More details on Life-Cycle Cost Analysis (LCCA) are given in Section 4 and Appendix 4. Overview of Street Lighting

14 Table 2-1: Lighting Terminologies and Basic Units Term Quantity is a Measure of Symbol English Unit Metric Unit Definition of Unit Luminous Intensity Ability of source to produce light in a given direction I candela (cd) Approximately equal to the luminous intensity produced by a standard candle Luminous Flux Total amount of light φ lumens (lm) Luminous flux emitted in a solid angle of 1 steradian by a 1 candela uniform point source Illuminance (Illumination) Amount of light received on a unit area of surface (density) E fc=lm/ft 2 lx=lm/m 2 One lumen equally distributed over one unit area of surface Luminance (Brightness) Intensity of light per unit area reflected or transmitted from a surface L cd/ft 2 cd/m 2 A surface reflecting or emitting light at the rate of 1 candela per unit of project area Note: 1 meter (m) = 3.28 ft; 1fc = lux 2.3 Standards, Regulations and Recommendations for Street Lighting The International Commission on Illumination (Commission Internationale de L Eclairage - CIE) has published various technical reports, recommended practices, and developed design guides and guidelines for roadway lighting applications. These include: The above-mentioned documents provide ways of improving nighttime visibility, and enhancing nighttime road safety. These CIE publications also give recommendations concerning average illuminance levels and overall uniformity of illuminance for different classes of roads, as well as measurement of street lighting illumination quality. CIE technical reports and recommendations have been referenced by regional and national standards agencies around the world in the formulation of specific lighting standards, including ones for roadway lighting applications. The AMS-II.L CDM methodology on demand-side activities for outdoor and street efficient lighting technologies, (approved by UNFCCC Executive Board in 2011) also references the aforementioned CIE documents. Keeping in line with recognized international recommendations and standards for roadway lighting, this document references the recommendations for average illuminance levels and overall uniformity (U 0 used in these guidelines, are fully consistent with the AMS-II.L CDM methodology. Detailed recommendations concerning illumination and uniformity, as well as measurement guidelines, are discussed in Section 4 of this document. For other applicable recommendations pertaining to street lighting luminaires and their components, please see relevant recommended standards, published by the International Electrotechnical Commission (IEC) 3. 3 The International Electrotechnical Commission (IEC), founded in 1906, is the world s leading organization for the preparation and publica tion of International Standards for all electrical, electronic and related technologies. These are known collectively as electrotechnology. Overview of Street Lighting

15 3 COMPONENTS OF STREET LIGHTING The components of a street lighting system are classified based on their respective functions. They are generally described as: Optical Systems: consisting of lamps, control gears and luminaires Structural Systems: consisting of poles and pole bases (foundations) Electrical Systems: consisting of control systems (which include service cabinets) During the design phase, these systems, and their component parts should be selected in order to meet all road and lighting recommendations at a minimum life-cycle cost. To achieve an effective, energy efficient design, it is essential to select the proper optical system. Careful selection of lamp/ballast and luminaire combinations will yield higher system efficiency while meeting design requirements and minimizing both glare and light pollution. 3.1 Optical Systems The optical system consists of the lamp, (also referred to as the electric light source ) control gears, and the luminaire body. These three components are described in more detail below Lamps The lamp is the most important component of the illumination system because it is largely responsible for determining the quality of light, system efficiency, and operating costs of the overall illumination system. The lamp transforms electrical energy into visible electromagnetic radiation, or light (lumens). The rate at which this conversion takes place is called luminous efficacy, and is measured in lumens per watt (see Appendix 1 for more details). The lamp s luminous efficacy, the color and distribution of its light, the depreciation 4 of light output over the lamp s lifespan, and the lamp s overall lifespan are all factors that affect the cost and effectiveness of its installation and maintenance. As such, these factors should all be considered when selecting a given light source. Various types of lamp technologies are currently available for street lighting application. These technologies vary greatly in their luminous efficacy, color rendering properties, lamp life, etc. (Please see Appendix 2 for description of terms). Most roadway lighting installations over the past decades use one of three types of high-intensity discharge (HID) lamp: high-pressure sodium (HPS), metal halide (MH) or mercury vapor (MV) lamps. Light-emitting diodes (LED) technologies have recently become more popular and affordable for roadway lighting, and these solid-state lighting technologies are more energy efficient than their predecessors, particularly in terms of the efficiency of overall optical system. A brief description of the different types of lamp technologies that can be used for street and outdoor lighting are provided in Table Depreciation refers to the degradation of light quality over a luminaire s lifespan. Such depreciation occurs to all luminaire s; however, the rate at which this process occurs varies both by make, and individual unit. Components of Street Lighting

16 Table 3-1: Types of Lamp Technologies Lighting Technology Lifespan (hours) Lumens per watt Colour Temperature CRI (Colour Rendering Index) Ignition Time Mercury Vapor Light 12,000 24, ,000K up to 15 min Metal Halide Light 10,000 15, ,000 4,300K 80 up to 15 min High Pressure Sodium Light 12,000 24, ,000K 25 up to 15 min Low Pressure Sodium Light 10,000 18, ,800K 0 up to 15 min Fluorescent Light 10,000 20, ,700 6,200K up to 15 min Compact Fluorescent Light 12,000 20, ,700 6,200K 85 up to 15 min Induction Light 60, , ,700 6,500K 80 instant LED Light 50, , ,200 6,400K instant Source: adapted from Issues to Consider Very inefficient, UV radiation, contains mercury UV radiation, contains mercury and lead, risk of bursting at the end of life Low CRI with yellow light, contains mercury and lead Low CRI with yellow light, contains mercury and lead UV radiation, contains mercury, prone to glass breaking, low wattage Low life / burnout, dimmer in cold weather (failure to start), contains mercury, low wattage Higher initial cost, contains lead, negatively affected by heat Relatively higher initial cost Components of Street Lighting

17 3.1.2 Control Gears The control gear generally serves the following three functions: Provides initial voltage and current to start the lamp. Keeps the lamp operating within its design parameters (input current and voltage). This prevents it from reaching high levels and getting destroyed during normal operation. Adapts the lamp to any supply voltages available, for example 240 volts or 120 volts which are commonly used by South and North Pacific Island countries respectively. In the case of HID and fluorescent lighting, ballasts are the main component of the control gear. Some HID lamps require an additional igniter to achieve proper starting voltage and current. For LED lighting, a small electronic power supply, called an LED driver, converts the supply voltage into low voltage direct current. Figure 3-1: Typical HID Lamp and Control Gear Circuit Phase Ballast Capacitor Igniter Lamp Capacitor Igniter Neutrol Ballast Photograph Courtesy of Lumitron Lighting International Co.,Ltd., Figure 3-2: Typical LED Array and Driver Circuit Phase + LED Array LED Driver LED Driver LED Array Neutrol _ Photograph Courtesy of Lumitron Lighting International Co.,Ltd., Components of Street Lighting

18 3.1.3 Luminaire The term luminaire can be defined as a complete lighting apparatus consisting of the housing and all integral parts necessary for both mounting, and function. This includes the light source (lamps), optical control parts, control gears, wiring assembly, and structure. Luminaires for roadway lighting are typically made of metal or plastic, and are shaped in the "cobra head" style, high mast style, vertical head style or shoebox" style (see Figure 3-3 to Figure 3-6). LED luminaires (Figure 3-7) are available in various designs and shapes. Most LED luminaires are available in modern flat rectangular designs, and others look similar to luminaires for HID lamps (such as the cobra head design) Luminaire Design and Construction Features The housing for luminaires is generally made of heat-treated, die-cast aluminum or aluminum-alloy, and is painted with an electro-coated grey paint finish. Luminaires should be corrosion-proof or be protected by finishes approved for corrosion-resistance. In generally, no special tools should be needed for inserting and withdrawing lamps from the luminaire body. The common test standard for luminaires referenced by luminaire manufacturers is IEC , which specifies general recommendations for luminaires, covering: classification of luminaire, marking, mechanical construction and electrical construction. This test standard should be referenced when purchasing street lighting luminaires. Below are common luminaire designs for HID lamps and LED for street and outdoor lighting. Figure 3-3: Cobra Head Style Luminaires Figure 3-4: High Mast Style Luminaires 5 The specific IEC standard for luminaires for road and street lighting is IEC Particular requirements Luminaires for road and street lighting. Components of Street Lighting

19 Figure 3-5: Vertical Mount Style Sy Luminaire Figure 3-6: Shoebox Style Luminaires Figure 3-7: LED Style Luminaire Optical Control The optical element of a luminaire, (such as the reflectors, refractors and lenses) controls the light output distribution of a luminaire. It does so by reflecting and refracting the light output in order to obtain the desired distribution. These optical elements absorb light or redirect it in such a way that only a percentage of light emitted by the lamp escapes the luminaire. This percentage is the efficiency of the luminaire. Components of Street Lighting

20 Figure 3-8: Basic Functions of Reflector, Refractor and Lens in Street Lighting Luminaires Reflector Lens Refractor Reflector A reflector is used to change the direction of the light output. Its purpose is to redirect the otherwise wasted light output in the desired direction. The reflector is intended to efficiently direct the light into the required directions, while reducing it in directions where it might cause discomfort from glare. Figure 3-9: Reflectors used in HID and LED Luminaires HID Luminaire LED Luminaire Reflector Refractor Photograph Courtesy of Lumitron Lighting International Co.,Ltd., Refractors Refractors are a type of lens that use a prismatic shape to redirect both the light emitted by the system s lamp, and the light coming off the reflector. Refractors are often referred to as prismatic lenses. Refractors are most often used in cobra head luminaires, and have the double function of helping to protect the lamp from external damage. Figure 3-10: Refractor of a Cobra Type HID Luminaire Refractor Photograph Courtesy of Lumitron Lighting International Co.,Ltd., Components of Street Lighting

21 Lenses Light from LEDs can be focused and shaped by lenses. Such lenses are being used with increasing frequency in street lighting applications, as they can be used to redirect light, reduce glare, and even serve to protect the LEDs from water and ingress. Lenses in LED luminaires are usually classified as secondary optics and are fitted directly on the LED. Lighting manufacturers claim that LED lenses offer an optical efficiency of more than 90%, while luminaires with traditional HID lamps generally offer reflector efficiency of around 70%. Lenses allow light to be directed to exactly where it is needed, reducing light pollution and dramatically improving system performance compared to conventional light sources. Type I Type II Type III Figure 3-11: How LED Lenses Control Light Distribution Type IV Type V Source: Khatod - Optical Solutions for LED Lighting Photograph Courtesy of Lumitron Lighting International Co.,Ltd., Photometric Distribution Luminaires with different combination of optical control elements offer different patterns of light distribution. The basic characteristics of vertical (cutoff) and horizontal light distribution of luminaires are discussed below. (See Appendix 1 for description of lighting terminology) Cutoff Characteristics Full Cutoff A luminaire s light distribution is considered to be a full cutoff when the candlepower per 1,000 lamp lumens does not numerically exceed 0 (0%, at or above a vertical angle of 90 above nadir (horizontal) and 100 (10%) at or above vertical angle of 80 above nadir. This applies to any lateral angle around the luminaire. Figure 3-12: Cutoff Characteristics Full Cutoff Full Cutoff 90 o 80 o Components of Street Lighting

22 Cutoff A luminaire s light distribution is considered to be a cutoff when the candlepower per 1,000 lamp lumens does not numerically exceed 25 (2.5%) at or above a vertical angle of 90 above nadir (horizontal) and 100 (10%) at or above a vertical angle of 80 above nadir. This applies to any lateral angle around the luminaire. Figure 3-13: Cutoff Characteristics Cutoff Cutoff 90 o 80 o Semi-cutoff A luminaire s light distribution is considered to be a semi-cutoff when the candlepower per 1,000 lamp lumens does not numerically exceeds 50 (5%) at or above a vertical angle of 90 above nadir (horizontal) and 200 (20%) at or above a vertical angle of 80 above nadir. This applies to any lateral angle around the luminaire. Figure 3-14: Cutoff Characteristics Semi-cutoff Semi-Cutoff 90 o 80 o Non-cutoff When there is no candlepower limitation in the zone above maximum candlepower, the light distribution is considered to be non-cutoff. Figure 3-15: Cutoff Characteristics Non-cutoff Non-Cutoff 360 o Components of Street Lighting

23 Lateral Light Distributions As with vertical light distribution, lateral light distribution is also a characteristic of the given luminaire. The Illuminating Engineering Society of North America (IESNA) established a series of lateral distribution patterns. They are labeled: Types I, II, III, IV, and V (see Figure 3-16). Type I and V luminaires are regularly mounted over the center of the area to be lighted. Type I is used more often on rectangular patterns over narrow streets, while Type V is more frequently used in areas where light needs to be distributed evenly in all directions. As a result, High Mast lighting systems tend to use types V, and modified Type Is. Types II, III and IV are regularly mounted at the edge of areas needing light. Type II luminaires are used on narrow streets; type IIIs are used on medium width streets, and type IVs are used on wider streets. Figure 3-16: IESNA Lateral Light Distribution Classification Types Type I Type II Type III Type IV Type V Luminaire Protection International standards and recommendations have been used to classify luminaires according to the degree of protection they have against the ingress of dust, solid objects and moisture Ingress Protection Ingress Protection Ratings, or IP codes (sometimes referred to as the luminaire s International Protection Rating ) are published in IEC They are commonly used by street lighting luminaire manufacturers and lighting designers to define the ability of a given luminaire to protect itself from the intrusion of dust, water, and other objects (such as hands and fingers). Figure 3-17 illustrates how IP Codes work. Different ratings are assigned to different levels of protection against threats of intrusion a higher rating indicates a higher degree of protection from harmful intrusion, and a 0 or X rating indicates no protection at all. For example, IP54 refers to protection against dust (no harmful deposits), and protection against water splashing in all directions. 6 IEC Degrees of protection provided by enclosures (IP Code) describes a system for classifying the degrees of protection provided by the enclosures of electrical equipment. The current edition at the time of preparation of the guidelines was published in September Components of Street Lighting

24 Figure 3-17: Ingress Protection (IP) First Number IP 0 Second Number IP Components of Street Lighting

25 Impact Protection The Mechanical Impact (IK) ratings indicate the degree to which a luminaire s enclosure or casing protects it from external impact. Different IK ratings relate to the ability of an enclosure to resist impact energy (measured in joules (J)). IK ratings are published in IEC standards. Figure 3-18 illustrates how IK Ratings work. Each number indicates a corresponding degree of protection against external impact a higher rating indicates a higher degree of protection, and 0 or x rating indicates no protection. Figure 3-18: Mechanical or Impact Protection IK Code IK IK Code IK Components of Street Lighting

26 3.1.4 Photoelectric Controls Roadway lighting systems need to have a means of efficiently controlling the overall system. Most roadway lighting systems use photoelectric controls these can either affixed on luminaires or external to tem. Photoelectric controls are capable of automatically turning lighting systems on and off whenever necessary, and are able to operate in all weather conditions. Photoelectric controls should reliably provide the ability to switch on and off all types of light sources that form part of a given roadway lighting system. Photoelectric controls should be easy to remove and replace as a single unit, without the need for special tools. It is also important that they can easily be connected and disconnected from the electrical control gear, and that all of their terminals are easily accessible. Figure 3-19: Internal and External Installation of Photoelectric Control 3.2 Structural Systems Poles Type of Pole and Height In most cases, the poles used for mounting luminaires are owned by the local electricity distribution utility. These poles are primarily installed to support distribution and/or service wires, and are typically made of concrete, wood or steel. Since the poles are designed to accommodate additional loads, they are normally capable of supporting installation of additional lighting equipment and luminaires. In cases where dedicated (or independent) lighting poles are used, they should be made of hot-dip galvanized iron and steel products with matte or dull finished surfaces in order to prevent glare. The poles have an average luminaire mounting height of 8-10 meters for the single and double arm installation, and high mast poles have an average luminaire mounting height of 20 meters. Pole height affects the illumination intensity, uniformity of brightness, area covered, and relative glare of the unit. Higher mounted units provide greater coverage, more uniformity, and a reduction of glare, but provide a lower light level. Pole height should be based on recommended values for average luminance and uniformity for the target area (See Table 4-1). Since regulations are sometimes imposed by electricity distribution utilities, nearby airports and residential neighborhoods, it is important to coordinate with relevant officials before purchasing or installing posts. Components of Street Lighting

27 Pole Placement Pole placement is an engineering decision, which should be based on geometry, characteristics of the roadway, soil conditions, physical features of poles, environmental requirements, available maintenance space, available budget, aesthetics, and overall local lighting objectives. Figure 3-20 to Figure 3-23 illustrate some prevalent pole placements/configurations. (a) Single-sided. In this arrangement, all luminaires are located on one side of the road. This is the most common type of arrangement employed by electric utilities. Figure 3-20: Single-sided Configuration Photograph Courtesy of ledlampinchina.wordpress.com (b) Staggered. In this layout, lights are installed in an alternating pattern, on each side of the road in zigzagging, or staggered locations. Figure 3-21: Staggered Configuration Components of Street Lighting

28 (c) Opposite. In this configuration, streetlight poles are placed directly opposite each other along the road. Figure 3-22: Opposite Configuration Photograph Courtesy of ICS Engineering Inc, icsenggroup.com (d) Twin Central. A twin central arrangement is usually adopted on dual carriageways. The luminaires are mounted on T-shaped masts in the center islands of the road. In essence, this is a two (2) single-sided arrangement, placed back-to-back with the two mast arms mounted on a shared steel pole. Figure 3-23: Twin Central Configuration Photograph Courtesy of Philips, wrtl.co.uk (e) Twin Central in Combination with Opposite Arrangement. In certain instances, where adequate illumination cannot be met, a single-sided arrangement is integrated with twin central or staggered arrangements. Typically, streetlights along major roadways are staggered on single-sided posts, on opposite sides of the road. Pole-mounted street lights are typically installed meters apart, but this distance can reach 100 meters when using high masts. Roadside conditions may require that pole spacing be adjusted. Such adjustments should be determined based on the recommended levels of illumination, as indicated in the guidelines (see Table 4-1). Higher levels of illumination than the base levels are justified when overhead structures, safety, and object clearance restrict the placement of poles. It is also advisable to provide higher illumination levels at diverging and merging areas. Components of Street Lighting

29 3.2.2 Mast Arms (Mounting Brackets) Mast arms, mounting brackets, or horizontal brackets are used to support the luminaire at a lateral dimension from the pole. The mast arm length is usually 2-4 meters. The length of the mast arm should have a length that is coordinated with the proper photometric distribution of the luminaire. Figure 3-24: Mast Arms (Mounting Brackets) Photograph Courtesy of nongkhainewsonline.blogspot.com, forgotten-ny.com, millerberndmfg.com (left to right) Bases and Foundations The base or foundation of a lighting system is its central point of contact with the ground. These structures can have various designs (see Figure 3-25) but must always be capable of supporting the weight of luminaire, while remaining resistant to wind, vibrations, and other local variables. Figure 3-25: Base and Foundation for Lighting Pole Steel Base Concrete Base Tower Type Base Components of Street Lighting

30 3.3 Electrical Systems Grounding The metal ground box lids, exposed metal conduit, metal poles, and supplemental ground rods at pole foundations should be connected to the grounding conductor Voltage Drop Voltage drop due to resistance in electric wires and cables is an important consideration when installing new or retrofitting street lighting systems because it helps ensure that voltage at all luminaires is sufficient for proper operation. High voltage drop also indicates inefficient operation of the electrical system, resulting from excessive losses over distribution lines. Street lighting systems should be organized to account for all components, ensuring that even the furthest luminaires in the lighting circuit are able to receive their minimum required level of voltage supply. The amount of voltage drop between the power supply connection point (or feed point) and the furthest luminaires should not excess 3% of the system voltage Energy Metering In cases where lighting systems are not owned by the electric utility, energy meters should be provided and installed in accordance with local utility standards. In cases where utilities do own local lighting systems, end users have the right to request the installation of energy meters Service Cabinets There are two primary kinds of service cabinets pad, and pole mounted. These cabinets serve as the electrical service point (feed point) from electric utility to lighting systems. These service cabinets should be sized to accommodate the number of lights as desired, provided that the voltage drop does not exceed 3%. Street lighting service cabinets should include the following accessories and features: Service cabinet structures should be rain-tight enclosures with a pad-mounting gasket. The cabinet s roof should extend beyond the outer edge of the front door and back wall of the cabinet in order to reduce water build-up in and around sealed areas, such as the cabinet s door. Components of Street Lighting

31 Figure 3-26: Pad Mounted Service Cabinet Figure 3-27: Pole Mounted Service Cabinet Components of Street Lighting

32 4 Energy Efficiency Guidelines for Street Lighting in the Pacific DESIGNING AN ENERGY EFFICIENT STREET LIGHTING PROJECT The design and planning process is an important step in implementing any street lighting project. It is very important to coordinate the interest of municipality, utility and other stakeholders, as it helps provide an effective public service while avoiding ineffective investment. Project designers must understand street lighting recommendations and evaluate the area to be lit in order to make informed decisions on the kinds of lighting technologies to be used, and where luminaires should be placed. Implementing an effective street lighting project is largely dependent on a strong project design. Analyzing local needs, existing infrastructure, and available technology will give project designers a clear understanding of the potential cost and energy savings to be achieved by the overall project. This section provides guidelines on how to design an EE street lighting system it can be applied to both new and retrofitting project designs. The following flowchart in Figure 4-1 illustrates the steps to be taken when designing a street lighting project. Each box in the following chart is marked with a number that corresponds to sections in this chapter (Section 4). Please refer to the flowchart and the corresponding sections for detailed information on how to design a street lighting project. Designing an Energy Efficient Street Lighting Project

33 Figure 4-1: Designing an Energy Efficient Street Lighting Project Flowchart 4.1 Understanding Roadway Categories and Lighting Recommendations Classifying Roadways by Category Understanding Lighting Quality Recommendations 4.4 Measuring and Calculating Average Illuminance of Exiting Systems Retrofitting Systems Determining Actions Retrofits or New Systems New Systems 4.2 Short Listing the Appropriate Lighting Technologies 4.2 Short Listing the Appropriate Lighting Technologies Advantages of LEDs and HPS Lamps Advantages of LEDs and HPS Lamps A Quick Guide for Replacing FL and MV Lamps with LED and HPS Lamps (Retrofit Projects) 4.3 Simulating Lighting Design and Calculating Costs Design Components to Consider Simulating Lighting Design with Computer Programs Conducting a Life Cycle Cost Analysis (LCCA) 4.4 Measuring and Calculating Average Illuminance of Retrofitting / New Systems Designing an Energy Efficient Street Lighting Project

34 4.1 Understanding Roadway Categories and Lighting Recommendations Designers should take three key points into consideration when researching and forming their design for EE street lighting systems. First, they must understand the current and predicted needs of the area to be lit. Second, they must understand lighting quality recommendations and how they apply to the given roadway. Third, they must evaluate the financial ability of the owner to meet and address these needs in order to assess whether the project will proceed with retrofits or a completely new system. In cases where recommended lighting standards cannot be met with the available budget, it is generally accepted that some lighting is better than no lighting. Retrofits are generally directed at increasing efficiency to reduce costs and energy use with better (or at least equivalent) lighting quality. Implementing new lighting systems, by contrast, should aim to meet applicable lighting recommendations while achieving cost effective EE Classifying Roadways by Category Roadway categories are mainly defined by their functions, designed layouts and traffic conditions. CIE 115:2010 outlines parameters to be evaluated for determining roadway categories. These include: traffic speed; traffic volume; traffic compositions (types of vehicles); separation of roadways; intersection density; parked vehicles (along the roadway); and traffic control. Note that project designers should evaluate both the current and predicted traffic volumes of a given roadway for sustainable results to project design. These guidelines refer to 5 main roadway categories (as recommended by CIE 180:2007). 1. Residential Areas, Pedestrians and many non-motor vehicles 2. Largely Residential, but some motorized vehicles 3. Major Access Roads, Distributors and Minor Main Roads 4. Important Rural and Urban Traffic Routes 5. High-Speed Roads, Dual Carriage Ways Understanding Lighting Quality Recommendations The second step is to understand the lighting quality recommendations that apply to each roadway classification. Lighting quality recommendations have several components, and project designers should consider each category when planning their lighting project. The primary quality factors to assess include: 1. Average Illuminance Level: This is the measurement in lux of average levels of light distributed across the area being lit. Average illuminance level is among the most important factors to consider when determining lighting because it has implications on roadway safety as well as requisite electricity requirements and operating costs. 2. Overall Uniformity of Luminance, or Illuminance: This is the degree to which light is distributed across the overall roadway. Overall uniformity of illuminance is measured by dividing the minimum point of illuminance by the roadway s average illuminance. This average is important for safety reasons because it ensures that overall visibility between luminaires is adequate. This figure is described by U 0 in the Table Uniformity of Luminance, or Illuminance: Defined as the ratio of the minimum to the maximum, and designated U 1. This ratio indicates whether light distribution is even over the given area; it helps project planners ensure that lighting isn t too dim in any particular point of the roadway. 4. Lighting on Footpath and Surrounding Area: This considers portions of the roadway that are not in direct use. It takes into account a two strips 5 meters wide (one in the road, the other alongside), the illuminance on the off-road strip should be at least 50% of the other. Designing an Energy Efficient Street Lighting Project

35 5. 6. Glare: In highly motorized countries a 10% maximum (of direct luminance) is recommended on highways, while a range between 5% and 30% is acceptable for general traffic routes. These percentages are determined by the amount of light the luminaires project near the horizontal. Decreased glare results in decreased nighttime glow (or light pollution). Guidance: Although glare should be kept low, a small amount of direct light from the luminaires gives a useful sense of the "run" of the road ahead, and can forewarn drivers of upcoming junctions or roundabouts. With an understanding of both the roadway s function and the lighting quality recommendations, project designers can determine the relative lighting needs of their roadway. Recommended illumination levels for different roadways are given in Table 4-1, and can be used to determine respective lighting needs. Table 4-1: Recommended Illumination Level for Different Classification of Roads Category Average Lighting Level U 0 U 1 Residential Areas, Pedestrians and many Non-motor Vehicles 1-2 lux 0.2 n/a Largely Residential, but some Motorized Vehicles 4-5 lux 0.2 n/a Major Access Roads, Distributors and Minor Main Roads 0.5 cd/m 2 8 lux 1.0 cd/m 2 15 lux 1.5 cd/m 2 25 lux Important Rural and Urban Traffic Routes High-Speed Roads, Dual Carriage Ways Source: CIE 180: Determining Actions Retrofits or New Systems When financially viable, implementing a new lighting system allows for a greater degree of flexibility in the selection of different lighting technologies, and in turn provides greater opportunities for increasing light quality, and enhancing efficiency. Though the above lighting quality recommendations should be met whenever possible, some light is still better than no light. Although retrofitting allows for less flexibility and light-quality improvement, it normally requires lower initial investment, and can still be used to enhance system efficiency. In cases where sufficient funding for new lighting systems is not available (and when existing infrastructure already exists), retrofit projects are an effective way of enhancing energy efficiency while maintaining current light quality. When funding is available and new infrastructure is being built, it is important that project designers implement projects that both meet current and anticipated future needs while optimizing installation and system costs by considering high-efficiency luminaires. IMPORTANT NOTE: In the case of retrofitting projects, designers should carefully measure existing lighting quality levels prior to implementation. This provides a quality baseline against which to compare project results. Detailed instruction on how to conduct measurements can be found in Section 4.4. See flowchart at the beginning of this section (Figure 4-1) to understand how measurement should be factored into the project planning process. Designing an Energy Efficient Street Lighting Project

36 4.2 Shortlisting the Appropriate Lighting Technologies After determining the recommended lighting quality for the given roadway, and whether changes are to be made by retrofits or new lighting systems, it is necessary to determine the kinds of lighting technology to be used. Selecting the appropriate lamps and luminaires will have a substantial effect on improving overall system efficiency, while lowering costs, and energy consumption. As such, selecting two or three appropriate lighting technologies and using available tools and software to simulate design options and optimum quality solutions is an important step in the project designing process. Most street lighting installations use one of three types of high-intensity discharge (HID) lamps; high-pressure sodium (HPS), metal halide (MH) and mercury vapor (MV) lamps. HPS is the most commonly used light source for street lighting due to its high efficiency and long service lamp life. MH lamps provide efficiency values often equivalent to those of HPS, but have a significantly shorter lifespan. MV lamps are the least efficient technology for street lighting applications; however they are inexpensive to purchase, and have a relatively long service life. As a result, MV lamps are still prevalent in many Pacific Island Countries. When making street lighting purchasing decisions, it is important to consider more than initial investment costs; this means factoring in luminaire lifecycle and post-installation costs, such as operation, maintenance, and replacement. Higher efficiency and longer expected service life results in considerable reductions to maintenance and operation costs. In many cases, this means that a higher up front investment in durable, high efficiency lighting systems, will result in lower overall costs than cheaper, lower efficiency counterparts. Having factored in current trends and future predictions about efficiency, lifetime cycles, and the supply of commercially available lighting technologies in the Pacific, these guidelines recommend using HPS and LED lighting technologies. Section 4.3 outlines ways to simulate different options of selected lighting technologies and conduct life cycle cost analysis (LCCA) Advantages of LEDs and HPS Lamps On average, LED luminaires have the longest lifespan, and tend to provide the highest efficiency; however, HPS lamps also provide relatively long lifespans and good overall system efficiency. As a result, both LED and HPS systems have the potential to increase municipal lighting efficiency while reducing costs and energy consumption. The following two boxes consider some key features of each lighting technology. It is advisable to conduct detailed simulation and lifecycle cost analysis (described in Section 4.3 below) prior to making a final selection of lighting systems. Basic minimum technical requirements and specifications pertaining to HPS and LED luminaires can be found in Appendix 2 these should be referred to as part of the procurement process. Box1 and Box2 give further information pertaining to HPS and LED lamps. Designing an Energy Efficient Street Lighting Project

37 Box 1: Light-Emitting Diodes (LED) LED lamps have been commercially available since 1960, and their overall quality has steadily improved since initial release onto the market. In relation to street lighting application, LEDs provide two primary benefits: long service life, and high energy efficiency. The average LED lifespan for street lighting application is around 50,000 hours approximately 13 years at standard 10-hour/day operations. Although purchasing costs of LEDs are generally 2-4 times higher than those of standard HID lamps, their service life is 3-5 times longer than conventional lighting technologies. On average, LEDs consume less than half of the energy of standard lighting systems (with lowest efficiency starting at 90 lumens per watt), and require less maintenance and cleaning. These factors make LED lamps a cost-effective, and environmentally sustainable choice for municipal application, while their high color rendering make them desirable models for street lighting purposes, where high visibility is a requisite feature of lighting. Box 2: High Pressure Sodium Lamps (HPS) HPS lamps are a kind of Sodium Vapor Lamp that provide higher quality light rendering than their low-pressure counterparts. For street lighting applications, HPS are frequently used due to their relatively long lifespan and high energy efficiency. Although average lifespan and energy efficiency ratings are generally lower than those of LEDs, HPS lamps can deliver competitive features. Average lamp lifespans range between 15,000 and 40,000 hours, and deliver a high efficiency of lumens/watt at the beginning of the lamp s lifespan. These features make HPS a cost and servicecompetitive option when considering lamp selection for street lighting application A Quick Selection Guide for Replacing FLs and MVs with LED and HPS Lamps (for Retrofit Projects) When selecting LED or HPS lamps/luminaires, project designers should ensure that the downward lighting output of new luminaires is equivalent to (or better than) the existing ones. Table 4-2 provides recommendations on HPS lamp wattages and LED luminaire wattages for replacing existing fluorescent and MV street lighting in order to achieve energy savings while maintaining similar or better lighting quality. Table 4-2: Recommended HPS Lamp Wattage and LED Luminaire for EE Retrofits Existing Lighting Technology Fluorescent Fluorescent Typical Average Wattage Efficacy (W) (lm/w) Estimated Downward Luminaire Light Output (lm) 1 2,080 4,160 Recommended HPS Lamp Wattage Recommended LED Luminaire Wattage Mercury Vapor , Mercury Vapor , Mercury Vapor , Mercury Vapor , Mercury Vapor , Note: 1 Estimated based on luminaire efficiency of 65%. 2 Estimated based on lamp efficacy of 100lm/watt and luminaire efficiency of 70%; the total HPS luminaire wattage shall consider power losses in control gear. 3 Estimated based on LED efficacy of 100lm/watt and luminaire efficiency of 90%; Power losses in LED driver already included. Designing an Energy Efficient Street Lighting Project

38 4.3 Simulating Lighting Design and Calculating Costs Design Components to Consider Achieving desired lighting quality is largely dependent on the luminaires selected; however, their placement and configuration along the roadway are also of major importance to lighting appearance, and in turn to public safety. Below is a list of the key parameters to be considered by the project designer in order to meet the desired lighting quality recommendations: 1. Mounting Height: The greater the height the more light/power will be needed to achieve a given illuminance, but a more uniform result will be obtained. 2. Layout: Lighting poles can be on just one side of the road or both; pairs of lighting poles can be either opposite each other or staggered (see Section 3). 3. Spacing: The longer the spacing between luminaires, the lower the level of illuminance and the more uneven/patchy; however, small spacing result in greater cost and is not always practical. 4. Lamp Type: These guidelines recommend the use of long service life and high efficacy HPS lamps or new Light-Emitting Diodes (LED). 5. Luminaire: The actual luminaire chosen has to be suitable for the lamp type and power; the detailed information provided by commercial suppliers can be relied upon for this. To further illustrate these design parameters, below is a diagram illustrating street lighting geometry: Figure 4-2: Geometry of Street Lighting Mast Arms (Mounting Brackets) Luminaire Mounting Height Spacing Edge of Roadway Width of Roadway After having selected several viable options for luminaires and luminaire layouts (based on Figure 4-2), it is necessary to evaluate the functionality and overall life cycle costs of each respective option before making any final selection and proceeding with procurement and installation. The final selection should be made based on a clear understanding of how each respective system will look, and how much it will cost for the duration of its life cycle. These two factors allow the project designer to make informed purchasing choices, and to provide municipalities and utilities with estimates concerning performance, economic, and environmental costs Designing an Energy Efficient Street Lighting Project

39 4.3.2 Simulating Lighting Design with Computer Programs A number of computer-based programs can help project designers to simulate projected illuminance outcomes in order to preview different project designs. Due to the large amount of calculation required in this process, it is highly recommended that project designers use one of the many available computer programs to assist in simulating the different options and configurations available to them. Table 4-3 describes the different software available to project designers, and indicates where they can be found. Table 4-3: Lighting Design Software Tools Lighting Design Software Tool AGI32 Calculux Road DIALux SEAD Description AGI32 is a 3D lighting design and rendering software package for electric lighting and daylight analysis. AGI32 produces full-color renderings and predictive lighting system calculations simultaneously for all applications of electric lighting and day lighting in interior and exterior design projects. Complex architectural environments are easily created internally, or externally created 3D environments can be imported via DWG or DXF format files. A comprehensive library of manufacturers lighting product data is included. ( Calculux Road is a software tool that can help lighting designers select and evaluate lighting systems. The software is relatively easy to use. Although the built-in choices of luminaires are only limited to products from Philips Lighting, the software can read additional photometric files in IES and other formats. ( connect/tools_literature/software.wpd) DIALux is a free and complete software developed by DIAL GmbH for professional light planning is open to luminaires of all manufacturers for calculation and visualization of indoor and outdoor lighting systems. DIALux can calculate daylight, interior and exterior lighting, road lighting and emergency lighting. DIALux can import from and export to all CAD programs (e.g. DXF, DWG, SAT) and has photorealistic visualization with an integrated ray tracer. More than 66 free electronic catalogues and photometric files (e.g. IES, EULUMDAT, CIBSE) can be read in. ( The SEAD Street Lighting Tool is a free, easy-to-use calculator that can help purchasers make more informed choices regarding street lighting fixtures to help achieve up to 50 percent in energy savings. Supported by Mexico's National Commission for Energy Efficiency, India's Bureau of Energy Efficiency, Natural Resources Canada, Swedish Energy Agency and U.S. Department of Energy, the tool is designed to make the fixture evaluation process easier by assisting street light purchasers with evaluating light quality, energy use and costs for the most common road layouts. ( License Commercial Free Free Free Designing an Energy Efficient Street Lighting Project

40 4.3.3 Conducting a Life Cycle Cost Analysis (LCCA) An LCCA is a calculation that provides the total cost of a lighting system over its lifetime (from purchase to disposal).the two primary functions of LCCA are to compare different lighting technologies (or other energy-consuming products), and to determine the cost efficacy of corresponding system selection. Conducting an LCCA helps guide purchasing decisions by showing the actual value of a given lighting system from purchase to disposal, allowing cost comparison based on real value as opposed to initial investment costs. A system requiring lower initial investment may use more energy (higher operating cost), require frequent luminaire cleaning, (higher maintenance costs) and have a shorter lifespan (require replacement). Conversely, a system requiring higher initial investment may cost significantly less over the course of its lifespan for inverse reasons. NOTE: Light quality (color) is not factored in to LCCA. LCCA is a tool for comparing economic, and not visual value. As a result, it should be conducted in congruence with aforementioned computer simulations. Box 3: The LCCA Formula Life Cycle Costs = Cost to buy + Cost to maintain it (if any maintenance is required) + cost of energy to run it for its life + Replacement costs - Any salvage value An alternate configuration of the LCCA formula and a practical example which may be useful for engineering staff can be found in Appendix Calculating Financial Payback Periods In addition to an LCCA, a preliminary analysis of a simple financial payback period of a retrofit/new project can be conducted using the below formula: Simple Financial Payback (year) = Initial cost of the retrofit/new project Annual savings in energy and maintenance costs Example: The ABC municipality is considering replacing 100 sets of 250 watts mercury vapor (MV) luminaires with 100 sets of 90 watts LED street lighting luminaires. The electricity cost is $0.3 per kwh. The yearly operating hours of the system is 4,300 hours. Estimated Initial cost: Estimated Annual Savings: 7-90 W = 200 W per luminaire cleaning, changing igniters, ballasts, etc) required by LED luminaires 7 Each 250W MV luminaire consumes about 290W due to additional losses in control gear which are estimated at 15% of lamp wattage. Designing an Energy Efficient Street Lighting Project

41 In general, a simple financial payback under 3 to 5 years is considered favorable. In case a more rigorous financial analysis is required to determine financial Return On Investment (ROI) of the project before the final investment decision can be made, many online tools are available for helping with the calculations, for example: Measuring and Calculating Average Illuminance The following procedure should be used in two circumstances. First, in cases where retrofits are being undertaken, the measurement process should be conducted PRIOR to replacements. This provides a quality baseline against which post-installation measurements can be compared. The second point at which the Measurement process should be employed is after the installation process. In both cases, the methodology laid out by CIE 140:2000 should be used. Roadway Illuminance is a measure of the amount of luminous flux falling per unit area lumens/m 2, or lux (lx) and can be used as a method of comparing and verifying illuminance. In the case of retrofits, the baseline measurement taken before replacement of systems should be compared to illuminance present after retrofits. In the case of new roadway lighting systems, this measurement should be compared to the projected illuminance levels anticipated during the simulation process. This measurement and calculation process should be based on specifications provided in CIE 140:2000. CIE 140:2000 provides the basis for determining fields of calculation, the location of measurement or simulation points for lighting calculations, and calculation methods for average illuminance values, as well as uniformity and glare values across the field of calculation as described below. (a) The field of calculation should be typical of the area of the road or intersection that is of interest to the driver and pedestrian, and may include the footways, cycle-ways, and verges. As shown in Figure 4-3, adapted from CIE 140:2000. It should be bound by the edges of the roadway and by transverse lines through two consecutive luminaires. Figure 4-3: Illustration of Illuminance Field of Calculation and Measurement S D/2 D=S/N WL d=wl/3 Centre-line of lane Edges of lane First luminaire in calculation field d/2 Field of calculation Last luminaire in calculation field Source: CIE 140:2000 Designing an Energy Efficient Street Lighting Project

42 (b) (c) (d) For staggered installations, consecutive luminaires will be on opposite sides of the road. The calculation points should be evenly spaced in the field of calculation (see Figure 4-3) and their number should be chosen as follows. In the longitudinal direction, the spacing in the longitudinal direction should be determined from the equation. D = S/N where: D is the spacing between points in the longitudinal direction (m); S is the spacing between luminaires (m); N is the number of calculation points in the longitudinal direction with the following values: for S 30 m, N = 10 for S > 30 m, the smallest integer giving D 3 m. The first row of calculation points is spaced at a distance D/2 beyond the first luminaire (m). (e) In the transverse direction. d = W r /3 where: d is the spacing between points in the transverse direction (m); W r is the width of the carriageway or relevant area (m). The spacing of points from the edges of the relevant area is D/2 in the longitudinal direction, and d/2 in the transverse direction, as indicated in Figure4-3. (f) Luminaires that are situated within five times the mounting height from the calculation point should be included in the calculation. Calculation of average illuminance based on the measurement data can be performed using any spreadsheet tools. Illustrated in Figure4-4. is calculation of lighting quality parameters (average maximum, and minimum illuminance, and uniformity) of measurement data using Excel. A sample of lighting measurement sheet is given in Appendix 3. Designing an Energy Efficient Street Lighting Project

43 Figure 4-4: Calculation of Lighting Quality Parameters using an Excel Spread Sheet Shade of tree Illuminance (Lux) Maximum Average Minimum Uniformity (min/avg) 0.35 Illumination Contour (Lux) Designing an Energy Efficient Street Lighting Project

44 5 Energy Efficiency Guidelines for Street Lighting in the Pacific MAINTENANCE OF EE STREET LIGHTING Street lighting is a necessary but costly public service, requiring a great deal of investment in the overall design, procurement, installation, operation and maintenance of street lighting systems. In order to maximize the value while keeping costs at a minimum, it is important to carry out regular maintenance projects to ensure cost effective, and energy efficient lighting services. The scope of such maintenance projects should include: cleaning luminaires and all corresponding parts (including refractors/lenses, reflectors, lamps, and control gear components); inspection of electrical wiring; measurement of input voltage; and replacement of broken or dysfunctional luminaires lamp, and component of the control system (such as photoelectric controls). The frequency of maintenance must be based on the degree of local pollution, and take into account pedestrian and vehicular traffic, safety, security, and economic constraints. 5.1 Cleaning Luminaires Over time, dirt and airborne pollutants reduce effectiveness of each luminaires light output. The amount of time this will take, and the degree of light obstruction will depend on local pollution levels and the luminaire s level of sealing or protection from the elements. Loss of light output, and respective luminaire cleaning should be taken into account from the start of project design. 5.2 Lamp Replacement Lamps themselves gradually give less light output as they age this is known as lamp light depreciation. In addition, for any large number of lamps installed, there will be a fraction that fail prematurely. In order to address lamp light depreciation and premature failure, lamp replacement is a necessary component to any lighting project. There are two (2) commonly used approaches to lamp replacement: spot re-lamping and group re-lamping. In the case of spot re-lamping, individual lamps are replaced if and only if they fail. While this method has an intuitive appeal, it can be significantly more expensive (particularly in areas where labor costs are high). In the case of group re-lamping, all lamps within a specific group are replaced regularly, based on a predetermined replacement schedule. This is usually the most cost-effective approach, but should be adjusted to exclude lamps that have recently been replaced as a result of random failure. 5.3 Electrical Wiring Inspection All internal and external wiring installations should be inspected to check for broken or cracked terminal lugs, frayed or deteriorated conductor insulations, and the tightness of screws and loose connections. Loose electrical connection may cause overheating and damaged to the lighting system. 5.4 Measurement of Voltage Input Measurement should be conducted to determine input voltage to the luminaire. The required voltage input is necessary for all the electrical components of the luminaires (e. g., ballast, driver, and ignitor) to operate properly. Lower voltage input may damage the luminaire prematurely, causing a shorter lifetime. Maintenance of EE Street Lighting

45 As shown in Figure 5-1, HID lamps require more frequent replacement than LEDs due to shorter average lamp life. Figure 5-1: Comparison of Lamp Replacement Frequency of HID Lamp and LED 100 % Initial Lumens HID 2yrs HID Relamping 75% Output HID Relamping 70% Output L70 10+yrs LED Life Rating LED ,500 (2.8) 25,500 (5.5) 37,500 (8.4) 50,000 (11.2) Hours (Years) Maintenance of EE Street Lighting

46 6 Energy Efficiency Guidelines for Street Lighting in the Pacific APPENDIX 1: LIGHTING TERMINOLOGIES AND BASIC UNITS Ballast. A device designed to operate electric-discharge lamps by providing a starting voltage and current, and limiting the current from reaching a level high enough to destroy the lamp during normal operation. Color Rendering. A term used to describe the effect that a light source has on the apparent (conscious or unconscious) color of an object when it is compared to a reference light source. Color Rendering Index or CRI (of a Light Source). This is measurement system used to evaluate color rendering. This measures the degree to which the apparent color of a single object changes from one light source to another. It makes this measurements based on reference to a single light source, emitting a particular color temperature. Subsequent ratings are based on variance from apparent color from the constant light source. Values assigned to common light sources tend to vary between 20 to 100 CRI units, in which 100 indicates no color shift, and a low CRI rating suggests that the color of an object will appear unnatural under the particular source. Color Temperature. A form of specifying the color appearance of a light source, relating the color to a reference source heated to a particular temperature, measured by the thermal unit Kelvin. The measurement can also be described as the warmth or coolness of a light source. Generally, sources below 3,200 K are considered warm, while those above 4,000 K are considered cool sources. Distribution Utility. An electric cooperative, private corporation, government-owned utility, or existing local government unit, that has an exclusive franchise to operate a distribution system. Electric Utility. A private or government corporation, mainly responsible for the distribution of electricity to end-users or consumers. Efficacy. The number of lumens produced by a lamp for each watt of electrical power it consumes. The unit for measuring efficacy is lumens per watt. Illuminance. The density of luminous flux on a surface, measured in footcandles, fc (or lux, lx). One footcandle is the illumination of a surface one square foot in area on which there is a uniformly distributed luminous flux of one lumen. One footcandle is lux. Illumination. Illumination is the density of luminous flux per unit area on an intercepting surface at any given point. Light. Visually evaluated radiant energy. Appendix 1: Lighting Terminologies and Basic Units

47 Lumen. This is the unit used to describe the quantity of light radiated from a light source. The lumen is the unit for measuring luminous flux, or light flow. It is the amount of luminous flux of light radiated into a solid angle of one steridian by the uniform light source of one candela used to describe the quantity of light radiated from a light source. Luminaires. Luminaires are complete lighting systems: they consist of the lamps, lens, wiring, and reflective materials used to direct light. Luminaire Efficiency. The ratio of total lumen output of a luminaire and the lumen output of the lamps, expressed as percentage. Luminance (Photometric Brightness). This describes the property of light we can see with our eyes. It is the quantity of luminous flux emitted, reflected, or transmitted from a surface in a particular direction, and is measured in candelas (cd) per unit area cd/ft 2 or cd/m 2. Luminous Flux. Time rate flow of light, measured in lumens (lm). One lumen is the amount of light which falls on an area of one square foot, every point of which is one foot from the source of one candela. A light source of one candela emits a total of lumens. Luminous Intensity. The force of luminous flux in a specified direction, measured in candela (cd). Lux (lx). The illuminance produced by a luminous flux of one lumen, uniformly distributed over a surface of one (1) square meter. Visibility. The degree to which something can be detected by the eye. Appendix 1: Lighting Terminologies and Basic Units

48 7 Energy Efficiency Guidelines for Street Lighting in the Pacific APPENDIX 2: LAMP REQUIREMENTS AND SAMPLE TECHNICAL SPECIFICATIONS 7.1 HPS Luminaire Requirements No. Requirement Table 7-1: HPS Luminaire Requirements Specifications 1 Design and Structure The luminaire shall be architecturally stylish in appearance, provided that the optical requirement is met and suitable for the usage area, and powder painted with high corrosion resistance. Luminaire shall be so designed such that installation and maintenance shall necessitate only minimal tools, preferably no tools. Material for the housing of the luminaire shall be made of die cast aluminum. The luminaire shall have appropriate lamp socket and suitable space provision for the lamp. All bolts and other fastening parts shall be corrosion resistant, preferably 300 series stainless steel. 2 Optical Assembly The optical reflectors shall be made of high-purity aluminum reflector. The optical assembly shall have a provision for easy lamp replacement. 3 Wiring The luminaire shall be pre-wired internally and externally in case an electronic photovoltaic control is required. 4 Protection Class (IP rating) IP 55 (for the entire luminaire, inclusive of the cable entry and gland). 5 Supply Voltage 220V - 240V, 50Hz (or the nominal system voltage used in the country). 6 Lamp and Control Gear Lamp Color Temperature (CCT): not less than 2100K Lamp Color Rendering Index (CRI): a minimum of 21 The lamp shall have a rated average life of 24,000 burning hours Lamp shall be clear, elliptical or tubular glass envelope Lamp dimensions shall conform to the requirements of either IEC standard, latest revision Appendix 2: Lamp Requirements and Sample Technical Specifications

49 No. Requirement Specifications Screw caps (bases) shall be E27 for 70-watt and E40 for 150-watt and 250-watt high-pressure sodium lamps. All lamps shall be externally ignited and designed to operate in a universal burning position. The following information shall be distinctly and durably marked on each lamp: a. Mark of Origin in the form of trademark or the manufacturer s mark. b. Rated wattage and voltage. The electronic ballast shall be equipped with thermal protection with a max Total Harmonic Distortion (THD) of 15%. All tests on lamp and control gear shall be performed in accordance with applicable testing procedures and acceptance criteria of IEC standard, latest edition. 7 Test Report IEC Luminaires Part 1: General requirements and tests IEC Discharge lamps (excluding fluorescent lamps) Safety specifications IEC High pressure sodium vapour lamps IEC Auxiliaries for lamps Ballasts for discharge lamps (excluding tubular fluorescent lamps) Performance requirement IEC Lamp controlgear Part 1: General and safety requirements IEC Lamp controlgear Part 2-9: Particular requirements for ballasts for discharge lamps (excluding fluorescent lamps) Equivalent national standards or latest edition of IEC standards shall be referenced. Testing laboratory/ies must be accredited according to ISO17025 and recognized by ILAC/APLAC for testing of HPS lamps, control gears and luminaires 8 Additional Documents Product specification sheet listing the brand name, model/type, type of coating, length and width (dimensions) Photometric data of the proposed luminaire 9 Quality of Production ISO or equivalent 10 Warranty Minimum 1 year Appendix 2: Lamp Requirements and Sample Technical Specifications

50 7.2 LED Luminaire Requirements No. Requirement Table 7-2: LED Luminaire Requirements Specifications 1 Design and Structure Shall primarily be constructed of metal. Finish shall be powder color coated and rust resistant. In case the LED driver unit is mounted internally, it shall be replaceable and accessible without tools. Any parts constructed of polycarbonate or acrylic shall be UV stabilized, any lens discoloration shall be considered a failure under warranty. Luminaire shall consist of heat sink with no fans, pumps or liquids and shall not degrade heat dissipation performance. Adjustable mounting socket shall be provided for mounting with existing mast arms diameter mm. 2 LED Modules/Arrays Color Temperature: a minimum 4000K Color Rendering Index (CRI): a minimum of 70 3 LED Driver Driver unit(s) shall be of constant current or constant voltage type with sufficient capacity to supply rated power required by LED module(s)/array(s) installed in the luminaire. Power factor: 0.9 Surge protection > 2 kv (Line-Neutral). 4 Luminaire Efficiency 90 lm/w 5 Lumen Maintenance At least 70% lumen maintenance at 50,000 hours (L70). 6 Protection Class (IP rating) IP 66 (for the entire luminaire, inclusive of the cable entry and gland) 7 Supply Voltage 220V to 240V, 50Hz (or the nominal system voltage used in the country) 8 Test Report IEC Luminaires General Requirements and Tests IEC Part 2-3: Particular Requirements Luminaires for Road and Street Lighting IEC Luminaire performance - Part 2-1: Particular requirements for LED luminaires IEC : General safety requirements IEC : Particular requirements for DC or AC supplied electronic control gear for LED module IEC 62384: DC or AC supplied electronic control gear for LED module IEC Assessment of lighting equipment related to human exposure to electromagnetic fields. EN 55015: 2006 and 2007 Limits and methods of radio disturbance characteristics of electrical lighting. Appendix 2: Lamp Requirements and Sample Technical Specifications

51 No. Requirement Specifications EN 61547:1995 / +A1:2000 Equipment for general lighting purpose EMC immunity requirements. EN :2006 Limitation of harmonic current emission. EN :2008 Limitation of voltage fluctuation and flicker. IESNA LM 80 LED test report Equivalent national standards or latest edition of IEC standards shall be referenced. Testing laboratory/ies must be accredited according to ISO17025 and recognized by ILAC/APLAC for testing of LED luminaire and its components 9 Additional Documents Product specification sheet listing the brand name, model/type, type of coating, length and width (dimensions) Photometric data of the proposed luminaire Salt spray test report Vibration test report 10 Quality of Production ISO or equivalent 11 Warranty Minimum 5 years (a full replacement of equipment/components and accessories) Appendix 2: Lamp Requirements and Sample Technical Specifications

52 8 Energy Efficiency Guidelines for Street Lighting in the Pacific APPENDIX 3: SAMPLE OF LIGHTING MEASUREMENT SHEET Figure 8-1: Sample of Lighting Measurement Sheet PROJECT: PEEP2 Place: Bypass Road, Ma ufanga (60m from the corner of Salote Road), Nuku'Alofa, Tonga Luminaire: Lamp: BRP371 LED86/CW 90W V DM2E MSP Spacing between luminaires: Street width: meters meters Height: 9.0 meters Tilt angle: 3.0 Degrees Measurement Grid D = 3.0 meters d = 2.4 meters Site Picture: Condition: Date: Time: 28 May hours Moon Phase: Sky condition: New Moon Clear N Result: Shade of tree Maximum Average Minimum Illuminance (Lux) Uniformity (min/avg) 0.35 Appendix 3: Sample of Lighting Measurement Sheet

53 9 APPENDIX 4: LCCA ALTERNATE FORMULA REPRESEN- TATION, AND EXAMPLE Formula: The following formula can be used to calculate the estimated Lifecycle Cost of a given luminaire system. Life Cycle Cost (LCC) = C i + C m + C e + C r - S Where C i ($) = the initial cost of the bulbs or the systems C m ($) = the cost incurred to maintain it in good operating condition. C e ($) = the total cost of electricity/ fuel required to run the bulb for its lifetime (usually cost per kwh ($/kwh)) C r ($) = the cost to replace the bulb (labor and equipment costs) S ($) = the value that the bulb/ luminaires can be sold for after its lifetime is over Example: The following example shows how this formula might be applied: Example: The ABC municipality is considering replacing 100 sets of street lighting. They conduct the LCCA between a set of 250 watts mercury vapor (MV) and 90 watts LED street lighting set. The cost of a single set of LED lamp and mercury vapor is $700 and $100, respectively. The electricity cost is $0.3 per kwh. The yearly operating hours of the system is 4,300 hours. Estimated Initial Cost (for replacement the same housing): two-person crew) = $ Total estimated initial cost = $78,000 (LED) and $18,000 (MV) Appendix 4: LCCA Alternate Formula Representation, and Example