Lighting Workshop

transcript

Fundamentals of Energy Efficient Lighting

Presented By:Ken Currie, PhD, P.E.September 19, 2013

US DOE Industrial Energy Efficiency

Building Lighting Energy

Building Lighting Codes

Lighting Type First Cost

Lighting Type Life Cycle Cost

Lighting Energy Efficiency

Efficient Lighting

Amount of Light

Other Considerations

Lighting Topics

TerminologyLight and ColorLighting Levels/StandardsLamp SourcesControlsTrendsPrinciples of Energy Management Case Studies

Lighting Terminology

IESNALumensLamp EfficacyLamp Loss Factors

Lighting LevelsFoot-candle (Lux)Lamp Rated Life

Electromagnetic Spectrum

Cosmic Rays

Gamma Rays X-Rays UV Infra-

RedMicro-Waves TV RadioElectric

.00001 nm.001 nm 1 nm 10 nm .0001 ft.. 01 ft.

1 ft.100 ft.

1 mi.3100 mi.

400300 500 600 700 1000 1500

Wavelength (Nanometers)

Visible Spectrum InfraredUltraviolet

ABC HEAT

Electromagnetic Spectrum

Violet: 380 - 450 nm*Blue: 450 - 490 nmGreen: 490 - 560 nmYellow: 560 - 590 nmOrange: 590 - 630 nmRed: 630 - 760 nm

* nm = 10-9 meters

Solar Spectrum

Lamp Radiation Spectrum

Light & Color

Color Temperature

Color Temperature is noted in degrees Kelvin* or °K

3,000°K - Warm White3,500°K - Neutral

4,100°K Cool White

* The Kelvin Scale is defined as Celsius plus 273.

Color Temperature Definition

• the electromagnetic radiation emitted from an ideal black body

• 1,700 K Match flame• 1,850 K Candle flame, sunset/sunrise• 2,700–3,300 K Incandescent lamps• 3,000 K Soft White compact fluorescent lamps• 3,200 K Studio lamps, photofloods, etc.• 3,350 K Studio "CP" light• 4,100–4,150 K Moonlight• 5,000 K Horizon daylight• 5,000 K tubular fluorescent lamps or Cool White/Daylight CFL• 5,500–6,000 K Vertical daylight, electronic flash• 6,500 K Daylight, overcast• 5,500–10,500 K LCD or CRT screen• 15,000–27,000 K Clear blue poleward sky

Typical Color Temperatures

Incandescent ……... 2,750°K – 3,400°K Fluorescent ……….. 2,700°K – 6,500°K

Mercury vapor ….. 3,300°K – 6,000°K Metal Halide ……… 3,000°K – 4,300°K High PressureSodium …………...... 1,900°K – 2,200°K Induction …………… 3,000°K – 4,000°K

Color Temperature

Color Rendering Index (CRI)

Color Rendering Index is a scale from 0-100 that indicates the accuracy with which a lighting source can reproduce colors. The higher the CRI value the more accurate the color reproduction.

Color Rendering Index (CRI)

Typical high CRI values: 80 to 90

Typical good CRI values: 65 to 80

Typical poor CRI values: <65

Note: The CRI for standard Low Pressure Sodium lamps is extremely poor.

Typical CRI Values

Incandescent …………….. 100 Fluorescent ………………. 60 - 90

Mercury vapor …………….15 - 30Metal Halide ……………… 60 - 90High Pressure Sodium ….. 10 - 60

Low Pressure Sodium ….. Negative Induction ………………….. 85

LEDs……………………………. 30 - 60

Color Rendering Index - Example

Rated Life of a Lamp

The rated life of a lamp is defined as the point at which 50% of a test sample fails.

Rated Life of a Lamp

For non-HID lamps (incandescent, fluorescent, etc.) the test sample operating time is 3 hours.

For HID lamps (MV, MH, & HPS) the test sample operating time is 10 hours.

Lamp Life Comparison

Light & Distance

The lighting level drops off as the square of the distance.

E = I/d2

Where: E = Illuminance (footcandles or lux) I = Intensity of lighting in Candelas D = Distance from the source

Light & Distance

Therefore, even small changes in the mounting height of a luminaire can have a significant impact on the lighting level.

0%100%50%

Lumen Maintenance

% Rated Life(Lumen output of all light sources depreciates as they age.)

Lighting Standards (IESNA Handbook)

Light Meters

Lighting Levels

• Specific tasks to be performed• Time required for each task• Speed and accuracy• Age of occupants• Safety and security• Aesthetics• System operating cost

Lighting Sources

Sources Efficacy

Tungsten LEDwarm Mercury Vapor LEDcool Fluorescent Induction Metal Halide HPS LPS0

Lighting Source Efficiency

Source Efficacy

Incandescent Lamps

Advantages1. Inexpensive2. Available in many configurations and colors3. No warm-up required4. Not temperature sensitive5. Easily controlled

Incandescent Lamps

Disadvantages1. Inefficient (10 - 25 lumens/watt)2. Short lamp life3. Vibration sensitive4. Over-voltage sensitive

Incandescent Upgrades

Halogen Lamps

Advantages:1. Higher efficacy than standard lamps2. Better color rendering3. Longer life (2,000 hours)Disadvantages:1. Same as standard incandescent2. Higher price

Ballast Functions

Fluorescent Lamps

Lamps are available it the following configurations:

T-5 T-12 (being phased out)

T-8 T-17 (PG-17)

T-10Note: In dual pin configurations, T-8, T-10, and T-12 lamps

have the same pin spacing. Therefore, they can be used in the same fixture.

Fluorescent Lamps T-12 Lamps

Tubular lamp 12/8 of an inch, or 1.5", in diameter.

This type lamp comes in a variety of wattages and configurations.Typical Lamp Wattages: 34W, 40W, 60W, and 95W

Fluorescent LampsT-8 Lamps

Tubular lamp 8/8 of an inch, or 1.0", in diameter. This type lamp comes in several lengths and is typically used with electronic ballasts.Typical Lamp Wattages: 32W, 59W and 86W

2800 lumens (32 watt bulb)

Fluorescent LampsT-5 Lamps

Tubular lamp 5/8 of an inch in diameter. This type lamp comes in several lengths and is typically used with electronic ballasts.

Typical Lamp Wattages: 24W(21.6″), 39W(33.4″) , 54W(45.2″), and 80W(57.0″)

Low Mercury Lamps

In 1980 a four-foot T-12 fluorescent lamp typically contained approximately 100 mg of mercury. By 2000 that value has been cut by over 90%.

Fluorescent Ballasts

Electromagnetic Ballast (no longer produced)

Ballasts perform two basic functions: 1. Provide the higher voltage required to

start lamps

2. Stabilize the lamp current

Solid State Electronic Ballast

Electronic Ballast Advantages

1. Power (energy) savings2. Reduce heat generation – potentially lower

air conditioning requirement3. Longer life than electromagnetic ballasts4. Potentially fewer ballasts required per

fixture5. Additional control flexibility

Electronic Ballasts

Input Wattage Comparison of Four-Lamp Fluorescent Fixtures

Electromagnetic Electronic 144 110 -124

Approximate wattage comparisons

Compact Fluorescent Lamps

Typical Lamp Wattages

9W, 11W, 15W, 18W,

20W, 23W, and 28W(Larger wattages available)

Reflectors

• Reflectors allow the user to direct most of the light downward toward surfaces of interest instead of lighting the ceiling.

• Reduce electric consumption by reducing the number of lamps required for desired light output.

• 3 Types (Reflective Efficiency)– Standard Aluminum Reflector (86%)– Reflective White Paint (91%)– Enhanced Specular Aluminum (95%)

HID Lamp Types

HID Lamp Characteristics

All HID lamps share certain physical and operating characteristics. – All HID lamps utilize an internal arc tube and outer

envelope construction.– They all require a ballast for operation.– All HID lamps require a warm-up period.– They all require a cool-down period before they

can re-strike.– A stroboscopic effect may occur prior to lamp

failure

Mercury Vapor Lamps

Mercury vapor lamps produce a bluish-green color light. Due to their lower efficacy and poor color rendition they are seldom used in new construction.Interior applications are minimal. Most current uses are for outdoor area/ parking lot lighting.

Metal Halide Lamps

All MH lamps offer a number of advantages over MV lamps, including:

- Higher efficacy (~ 100 lumens/watt)- A crisp clear white light- Excellent color rendition (CRI 70 - 80) Also, reduced wattage lamps are available for selected sizes of standard

MH lamps.

Metal Halide Lamps

Disadvantages for MH lamps include: - Shorter lamp life for equivalent sizes, when compared to other HID sources (6,000 to 16,000+ hours) - Higher lamp cost - Orientation sensitive

Metal Halide Lamps

Disadvantages for MH lamps include:

- Color shift near the end of lamp life - NEC 2005 requirements: The use of metal

halide lamps must be- enclosed to provide contamination barrier (Type S lamps) or- used in a lamp holder that will only accept ANSI Type O (shrouded) lamps

Probe-Start Metal Halide Lamps

Pulse-Start Metal Halide Lamps

Electronic-Start MH Lamps

Metal Halide Lamps

• UV Protection

• Can Explode

HPS Lamps

High pressure sodium lamps have been used extensively for both interior and exterior applications. Due to their high efficacy (~120 lumens per watt).

Since the mid 70’s HPS fixtures have been used extensively for street lighting.

HPS Lamps

High pressure sodium lamps provide a golden-yellowish color light. This is due to the fact that they do not produce light in the blue spectrum (450 - 490 nm). While not a concern in exterior applications, some find the resulting color unacceptable for interior use, especially if color is a consideration.

HPS Lamps

In many applications high pressure sodium lamps are being changed to fluorescent. Often, a 460 Watt HPS lamp can be replaced with a 210 Watt T-5 fluorescent fixture or a 220 Watt T-8 fixture

LPS Lamps

Typical LPS Lamp Design

LPS Lamps

Low Pressure Sodium is not an HID source. It is a gaseous discharge type lamp, similar in operation to fluorescent lamps.

LPS Lamps

While very efficient, (producing about 160 lumens/watt), LPS lamps are a monochromatic light source. They produce only one color of light, a dirty yellow.

LPS Color

Color reproduction is so poor that under the Coloring Rendering Index scale the CRI for low pressure sodium is Negative.

Induction Lamps• Electromagnetic transformers create a field around a glass

tube containing a gas• The high frequency ballast creates a flow of free electrons

which collide with mercury atoms and increase their energy state

• When the mercury atoms return to their lower energy state they emit ultraviolet radiation

• The UV radiation is converted to visible light as it passes through a phosphor coating on the surface of the tube

Induction Lamps• Induction lamps are basically electrodeless fluorescent

lamps• Without electrodes the life of the lamp can be extended to

100,000 hours• Efficacy is 85 lumens/watt• CRI is 85

Induction Lamps

Advantages:1. Efficient (~50% less energy consumption)2. CRI of 853. Longer life (100,000 hours)4. Instant On & Off5. 85+ Lumens per Watt

Induction Lamps

Disadvantages:1. Contains Mercury2. Slow Start in the Cold3. Cannot be dimmed or focused4. Produces UV Light

Induction Lamps

LED Lamps

LEDs are made from semi-conductor materials on a die

LED Lamps

An Individual LED Die is Very Small

LED Lamps

Making White Light with LEDs

- Can mix light from Red, Blue and Green LEDs

- Can use phosphor conversion

LED Lamps – Mix RBG Light

LED Lamps – Phosphor Conversion

Blue LED Excites the Phosphor

Excited Phosphor

Emits White Light

LED Lamps

Phosphor Conversion is Similar to Fluorescent Lamp Operation

LED Lamps – White Light with Phosphor Conversion

LED Lamps – Efficacy

LED Lamps – Packaging

LED Lamps – Lamp Life

LED Lamps

LED Lamps - Applications

Lamp Comparison

Exit Signs

Types of Illuminated Exit Signs- Incandescent- Fluorescent- LED- Tritium- Photoluminescent

Illuminated Exit Signs

Incandescent Exit Signs

Incandescent signs typically utilize two 20 or 25 watt tubular lamps.

Inefficient and short lamp life (2,000 hours).

Fluorescent Exit Signs

Fluorescent signs typically utilize one or two lamps.

More efficient that incandescent with longer lamp life (6,000 -10,000 hours).

LED Exit Signs

In new or retrofit applications two lamps are typically used.

Very efficient (4-8 W/fixture), excellent lamp life

(20 years).

LED retrofit lamp

Tritium Exit Signs

No energy required, rated life 10 -20 years

However, disposal problems exit

Photoluminescent Exit Signs

No energy required, glow in the dark (non-tritium) exit signs

Rated life 5 -25 years depending on model

Should comply with UL924 for exit signs

Courtesy of American Permalight

Exterior Lighting

• LED Street Lights• Wall Packs– High Pressure Sodium– Mercury Vapor– Metal Halide– Induction

• Controls– Photocells– Timers

Lighting Controls

Occupancy Sensors

Most sensors in commercial applications utilize either passive infrared (PIR) or ultrasonic technology. There are hybrid sensors employing both technologies.

Occupancy Sensors

Typical sensor fields of view

Timeclocks

Timeclocks can be effectively utilized for basic on/off operation of lighting fixtures. By utilizing low voltage relays, large numbers of fixtures can be controlled by a single timeclock, thereby making it very cost effective.

Timed Switches

Timed Switches are switches that incorporate a timed function, to ensure that the fixtures are turned off after a preset interval of time, typically one to two hours.

Timed Switches

They are available in both standard toggle switch and programmable models.

Prior to the controlled fixtures being turned off, these switches will provide a warning; in the form of blinking lights or an audible beeping sound (or both on some models).

Scheduling Controls

Centrailzed Controls

Photocells

Photocells are low cost reliable controls that utilize a photo-sensitive element to control on/off operation of a fixture or fixtures. While primarily used in outdoor applications they can also used in building atriums.

Light Control Panels

Typical Industrial Lighting Panel

Lighting Control Panels

Today, control panels have become very sophisticated, with control capabilities far beyond basic on/off operation, i.e. “smart panels”.

Daylight Harvesting

Building Automation Systems

Twilight Switch

HVAC Impact

Basic Principles of Lighting Energy Management

1. If you don’t need it, turn it off - Employee Awareness, Sensors,

Timers, Photocells, Timed Switches, Energy Management Systems, etc.

2. Proper maintenance - Group cleaning and relamping

Basic Principles of Lighting Energy Management

3. Enhanced lighting control- Photocells and occupancy sensors

4. More efficient sources- Electronically ballasted fluorescent fixtures,- Compact fluorescents- Induction lamps- Light emitting diodes (LEDs)

Case 1: Manufacturer

Case 2: Dairy Product Processor

Electric Rates: Usage: $.0400/kWh Demand: $0.0/kW

Operating Hours of Fixtures: 8,760 hours/yr

Background: Portions of the production area are lit with (125) 2x4 T12 fixtures

(4 – 4’ T12 lamps with magnetic ballasts)Power Rating: 144-watts

Annualized Maintenance Cost per fixture: $17.11

Recommendation: Replace with (125) 2-lamp T8 fixtures with (1) parallel-wired

electronic ballast and reflectors.Power Rating: 55-watts

Annualized Maintenance Cost per fixture: $6.63

Savings:Usage: 97,455 kWh/yr $3,898 / yr

Demand: 134 kW/yr $0 / yrMaintenance: $1,310 / yrTotal Savings: $5,208 / yr

Implementation Cost: $11,100

TVA Rebate: $9,746

Simple Payback Period: 2.13 years (0.26 yrs)

Case 2: Dairy Product Processor

Case 3: Automotive Components Manufacturer

Background: (31) Exit fixtures are equipped with (2) 20-watt lamps each

Power Rating: 40-wattsAnnualized Maintenance Cost per fixture: $25.81

Recommendation: Replace with (31) LED exit fixtures, each with (2) 2-watt LED lamps

Savings:Usage: 9,776 kWh/yr $391 / yr

Demand: 13 kW/yr $0 / yrMaintenance: $511 / yrTotal Savings: 902 / yr

TVA Rebate: $978

Case 3: Automotive Components Manufacturer

Case 4: Auto Parts Manufacturer

Background: There are (114) 400-watt metal halide fixtures throughout the facility

Power Rating: 450-watts/fixtureAnnualized Maintenance Cost per fixture: $19.71

Recommendation: Replace with (114) 220-watt T8 fluorescent fixtures

Savings:Usage: 229,058 kWh/yr $14,889 / yrDemand: 314.6 kW/yr $3,924 / yrMaintenance: $906 / yrTotal Savings: $19,719 / yr

TVA Rebate: $22,906

Case 4: Auto Parts Manufacturer

Questions ???????????

Lighting Workshop

Business