Small Commercial

Business

Energy Audits Recognizing and

addressing the special

requirements of the small

business market segment.

Class 4:

Lighting Fundamentals

Basic Lighting Technology

Advanced Lighting Technologies

The Lighting Survey

Class 4

Reading Assignment Review

Class 4

Why Does Lighting Matter?

Lighting represents about 22% of electricity consumption in typical retail store, not including effect on cooling loads

Lighting retrofits can save 30-50% of lighting energy, as well as 10-20% of cooling energy4

Lighting is a major determinant of workers’ satisfaction with their indoor environment, and has been shown to directly affect productivity

Class 4

Lighting Technologies –

3 Generations

Improving efficiencies (lumens per watt)

Class 4

Incandescent

LED

Fluorescent & HID

Lighting Technology: Efficacy

Class 4

Efficacy = lumens per watt

Source: Virginia Energy Savers Handbook (2005)

Lighting Terminology: Basic

Ballast

Candela

Efficacy

Efficiency

Fixture

Footcandle

Lamp

Life

Lens

Lumen

Reflector

Class 4

Lighting Fixture Types

Discussion: What do you think are the implications of the

different ways these fixture distribute light?

Class 4

Lighting fixtures may send all or most of their light downward (A),

upward (B), or a mixture of the two (C).

Lighting Power Density (LPD)

Expressed as the ratio of lighting power

consumption to floor area:

Watts per Square Foot (W/ft2)

Used in standards and code to define allowable

lighting installations

Let’s do a practice calculation.

Maximum lighting power permitted per unit area of a

building classification or space function.

Class 4

Basic Lighting Retrofit Calculation

Savings = (Existing W – New W) x Burn Hours/yr.

Sample Problem If a fixture currently uses a 60-watt bulb, and is left on 4 hours

per day, how much will you save by switching to a 13-watt CFL bulb for the same number of hours?

DISCUSSION: What happens to the retrofit savings if the

number of burn-hours is reduced by controls?

Class 4

Newer Technologies

T5, T5HO and High-Performance T8

HID sources (metal halide, high-pressure sodium)

LED

Induction lighting (outdoors)

Next generation technologies

Class 4

High-Performance Fluorescents

and HID

T5, T5HO and HPT8 High-output fixtures for high-bay applications

HID – improves characteristics of high-pressure sodium (HPS) and metal halide (MH)

Low-wattage lamps

Good color rendering properties

Higher efficacy, longer average rated life and greater light output than incandescent lamps

DIMMABLE with special ballast – daylight “harvesting”; can be used with occupancy controls

Class 4

T5 and T5HO Lamps

5/8” in diameter – 40% smaller than T8 lamps; almost 60% smaller than T12 lamps

Need special ballasts to operate

Slightly shorter, so cannot replace T8 or T12 lamps without changing sockets and ballasts

Standard output: 14, 21, 28 and 35 watts

High-output (T5HO): 24, 39, 54 and 80 watts

Efficacy equivalent to T8 lamps, but compact size reduces materials used in manufacture, potential for toxic substance contamination, and packaging materials – so may have less environmental impact

Class 4

High Performance T8 Systems

HPT8 can be considered against T5

Fixtures can be re-fitted

Improved lamp and ballast performance

Higher lumens

Longer life

Higher CRI rating

No issues with dimming

Class 4

LED Lighting Systems

Very high efficiency - 20-40% of fluorescent wattage for similar light output

Longer lamp life - up to 100,000 hours (5 - 10 times fluorescent lamp life)

Very effective and efficient for colored light applications, as they require no filtering

Dimmable

Lots of activity in creating retrofit kits

Class 4

LED Lighting Systems

Increase efficiency at low temperatures (where fluorescents lose efficiency)

Makes them especially effective for refrigerated cabinet retrofits

Class 4

LED Lighting Systems

Barriers and Disadvantages

High first-cost, but declining

Point sources – fixture must mask or glare can result

Pure color source – must be blended and/or filtered to produce “whites” at various points on spectrum (“warm-to-cool”)

Must provide for high heat dissipation at electronics

New technology – early failure risk

Class 4

Photo Credit: U.S. Dept. of Energy

Next Generation

Fiber Optic

Fiber Optic cable excited by source, such as solar or LED

High CRI provides bright, accurate illumination – purest white light available

No UV radiation, so no material fading

Lights without transmitting heat through the cable, so reduces ambient temperature and heat risk to merchandise

Many light points serviced by only one illuminator allowing for easy access for routine maintenance

Class 4

Next Generation

Induction Lighting

Contain no electrodes or filaments, so has an extremely long lamp life (up to 100,000 hrs.)

Can produce a substantial amount of light in a relatively compact package

High installed cost, but can be cost-effective in applications where maintenance is difficult, hazardous or costly (e.g., escalator wells, high-ceilinged spaces, parking garages, signage, exterior pedestrian lighting)

Lower-wattage induction lamps (20 and 23 watts) also available as direct replacements for medium-base and CFL lamps

Class 4

Photo Credit: Philips

The Lighting Survey

Class 4

Used to

compile

detailed

information

on lighting

systems from

an electrical

and light

distribution

standpoint.

The Lighting Survey: Key Steps

Identify, define, designate AREAS that will be surveyed – rooms and other areas, by building, floor, etc.

Identify, designate and document the types of fixtures and lighting technologies, including controls

Determine operating hours in various spaces

Conduct the room-by-room survey

Measure lighting levels for a sampling of all types of areas and fixtures

Class 4

The Lighting Survey: Other

Considerations

Method of hanging

Height of tasks & fixture mounting height

Ceiling type

Lighting quality issues

Room surface reflectances

Colors of major objects and room surfaces

Occupant feedback/complaints

Strategy: Use a tablet computer to help make your lighting survey more comprehensive. Take photos of spaces and fixtures; sketch a floor plan

and add details during your walkthrough; refer to spec sheets on the fly.

Class 4

Small Commercial

Business

Energy Audits Recognizing and

addressing the special

requirements of the small

business market segment.

Class 5:

Lighting Controls & Commissioning

Lighting controls

Schedule- and Occupancy-based

Daylighting

Lighting Quality (Intro)

Commissioning

Class 5

Reading Assignment Review

Class 5

Controls

Scheduling at lighting control panels

Occupancy sensors

Automatic dimming controls & daylighting

Class 5

Occupancy Sensors

Good application for rooms or areas with periodic use

patterns

Provide cost-effective energy savings without

compromising lighting service to occupants

Sensor performance is based upon:

Sensitivity – degree to which sensor can detect motion

Field of view – angle of view, determining both coverage

area and coverage pattern

Coverage area – physical limits of sensor’s ability to

detect motion

Class 5

Occupancy Sensor Types

Class 5

PIR (Passive Infrared)

Changes in temperature across

segmented field of view

Ultrasonic

“Doppler Shift” of frequency of

bounced sound waves

Sound waves not blocked by

partitions, corners

Hybrid

Combines both technologies in a

single device

Performance & Application

Class 5

Proper Specification

Matters

Sensor location: Wall,

ceiling

Sensor location: Range

of detection and obstructions

Sensor selection: Wrong

type for kind of motion

in the area

Sensor Issues & Strategies

Class 5

Operational Issues

• False triggering

• Failure to turn on

• False turn-off (failure to see occupant)

“Vacancy Sensor” – manual on, automatic off

Design Strategies

• Automatic on-switching for public areas; manual for private/semi-private areas

• Reduce sensitivity of sensor or reposition to prevent false triggering

• Make sure people can see which luminaires are turning on and off when they push a manual switch

• Make sure controlled luminaire groups correspond to occupancy patterns

Ultrasonic waves reflecting from a

moving object, changing in pitch and bouncing back toward sensor

Occupancy Sensors:

Bi-Level Lighting

Use when you don’t want

to turn off lighting

completely

Control alternate fixtures

Pre-wired fixtures

Class 5

Daylighting

Benefits

Energy savings

Reduced operational costs

Reduced maintenance

(shorter burn hours)

Look for architectural features and opportunities.

Class 5

Simple Daylighting Techniques A mix of top- and side-lighting, light shelves, high-reflectance ceilings, and wall diffusion provides fairly uniform deep-plan daylighting without the glare of direct sun.

Daylighting

Dimmable ballasts

required

Sensor maintains

setpoint lighting level

– dims electric

lighting in relation to

available day light

Control perimeter

fixtures

Class 5

Solatube

Tubular daylighting – uses

passive technology to

balance illumination

intensity, consistency, and

thermal performance

Captures the sun’s rays at

the roof level, then

transfers them indoors

through highly reflective

tubing

Class 5

Commissioning the Lighting System

After Installation

Make sure light levels meet design levels

Make sure color (CCT) is as specified

Aim accent lights

Calibrate lighting controls to ensure all lighting

systems perform as designed

Class 5

Lighting Quality

Goals of an effective and efficient lighting system:

Provide enough light for people to see and work comfortably throughout the day

Provide bright and uniform lighting in a space (with some caveats)

Do not create glare, distracting reflections, or discomfort for workers or visitors

Make colors and skin tones appear natural

Class 5

Lighting Quality: Getting A Retrofit

That Works

Energy

Savings

Client

Satisfaction

Class 5

Lighting Quality: Getting A Retrofit

That Works

Class 5

More Lighting Terminology

Color Rendering Index

Correlated Color Temperature

Glare

Illuminance

Light distribution

Light level

Luminance

Luminous intensity

Luminous efficiency

Class 5

Illuminance Levels

The IESNA Lighting

Handbook provides

recommended

illuminance levels

for various

applications.

Class 5

Small Commercial

Business

Energy Audits Recognizing and

addressing the special

requirements of the small

business market segment.

Class 6:

Lighting Quality

Lighting Quality

Color

Glare and Other

Retrofit Design Considerations

Class 6

Reading Assignment Review

Class 6

Light Meter Lab

Considerations

Different tasks require difference levels of

illuminance

The IESNA provides a reference for recommended

light levels

A light meter is used to measure illuminance, or

the density of luminous power

Equipment

Light meter

Class 6

Light Meter Lab

Exercise

1. Using the light meter, measure the illuminance

levels in four different spaces (indoor/outdoor)

2. Compare your measured readings with those

recommended by the IESNA; note whether your

measurements fall within the recommended

ranges

3. Discuss if those ranges feel appropriate

to you.

Additional Resources

The Lighting Handbook, IESNA, 10th Edition

Class 6

Color and Light

Correlated color temperature (CCT) – specification of the color appearance of the light emitted by a lamp, measured in degrees Kelvin (K)

Gives a good indication of lamp‘s general appearance

Warm = 2,700K, Cool = 10,000K

Color Rendering Index (CRI) – ability of a lamp to render colors, on a scale of 0-100 CRI of 70 or higher assures that colors and skin tones appear

natural

CRI of 80 or higher recommended in high-end retail stores where rendering of skin tones and merchandise is key

Changes in color characteristics may improve a store environment, but should be approached carefully, with pre-retrofit sample installations.

Class 6

Color Rendering Index (CRI)

Class 6

Color rendering

can have a

HUGE impact in

the display of

product!

Correlated Color Temperature

Class 6

Glare Fixtures that are uncomfortably

bright to look at or work under (direct glare)

Fixtures that cause reflections in computer screens (indirect/reflected glare)

Class 6

Luminous intensity: Amount of light coming from a fixture in a particular direction, measured in candelas (cd)

The number of candelas a fixture will produce at various angles will indicate whether comfortable to look at or too bright

Rule of Thumb: Select lighting fixtures that do not direct a lot of light toward people’s eyes or onto their computers.

Spacing Criteria

Class 6

Fixtures should not be installed too far apart from each other or too far away from the walls

Incorrect spacing causes uneven lighting and areas that will be too dark for people to see properly

Always install within manufacturer’s recommended spacing criteria

Distance between walls and adjacent lighting fixtures should not exceed ½ of manufacturer’s spacing criteria

Special fixtures (wall-wash) can be used to direct light onto walls or to the ceiling (fixtures suspended from the ceiling)

Lighting Design Considerations

Appearance of space and light fixtures should fit the image of the business

Color appearance

Direct glare

Reflected glare

Horizontal and vertical illuminance

Light distribution on surfaces

Points of interest (accent lighting)

Luminance of room surfaces

System control and flexibility

Class 6

Understanding lighting needs

What first impression do you want to have on visitors? (e.g., high-tech, modern, new, bright, spacious)

What does the lighting system have to do?

What tasks or activities?

Will computers be used?

What atmosphere should the lighting create? (intimate like a restaurant vs. bright, spacious like an office)

Class 6

Lighting Types

Ambient: General lighting, usually provided with fixtures mounted on, into or near the ceiling; lighting people need to move around the space

Accent: Lighting that makes the space more interesting or is used to direct people’s attention to areas of interest (e.g., decorative, wall sconces, track lighting)

Task: Provided in particular areas where people will be performing a certain task (e.g., desk lighting offices, lighting over a check-out counter in a retail store)

Class 6

How do these types of lighting

work together?

What is the relationship between ambient

and accent lighting?

How do you reduce the need for ambient

lighting?

Focal highlighting

Quantity of light on displays

Aiming flexibility of accent lighting

Class 6

Lighting Equipment Selection

Basics

Light distribution (diffuse, directional)

Performance characteristics (lumen output,

life, color, wattage)

How light should enter the space (down, up,

sideways)

Class 6

Special Effects

Modeling of object/shadows

Visual priority/organization

Class 6

Store Types and Typical Lighting

Configurations

Store type: Basic

High-activity, self-service

Mass merchandising/discount stores – hardware, fast food, grocery, bulk sales

Lighting purpose: Light all merchandise uniformly; good visibility for reading labels; bright, clean stimulating environment

Lighting strategy: Ambient lighting with limited accent lighting

Lighting Levels: 50-80 fc ambient lighting

Class 6

Store Types and Typical Lighting

Configurations

Store type: Intermediate

Average level of activity, most common type

Clothing, stationery, beauty shop, gourmet shops, accessories, housewares, furniture, small objects

Lighting purpose: Sufficient uniform illumination to see and examine product and read labels

Lighting strategy: Ambient lighting with limited accent lighting

Lighting Levels: 30-50 fc ambient lighting, 75-100 fc accent lighting

Class 6

Store Types and Typical Lighting

Configurations

Store type: Higher-end

Lower level of customer activity, more personalized sales assistance, more expensive/exclusive merchandise

Jewelry, gifts, antiques, fine clothing/accessories

Lighting purpose: Sufficient uniform illumination to see and examine product and read labels

Lighting strategy: Ambient + limited accent

Lighting Levels: 30-50 fc ambient, 75-100 fc accent lighting

Class 6

Color Temperature Lab

Considerations

What is color temperature?

Why is color temperature an important consideration in retail environments?

How does color affect consumer behavior?

Equipment

Chroma meter

Light box or similar setup with multiple bulb types/color temperatures

Sample retail items (e.g., clothing, food, jewelry, makeup)

Class 6

Color Temperature Lab

Exercise

1. Configure light box or similar setup with multiple

light bulb types/temperatures

2. Use Chroma Meter to measure color

temperatures produced by different bulbs

3. Place retail items in light box, observe changes in

appearance; take notes on differences in appearance when viewed under various color

temperatures

Additional Resources

Webinar: Fundamentals of Color, Konica Minolta

Class 6

Case Studies

Energy-related(e.g., delamping may be

possible if using lamps with higher color

temperature [e.g., 4100 K vs. 3500 K] that give

off more blue light)

Behavioral (i.e., light and shopping behavior)

Class 6