Use of LED Technology within a PRW

Michael Lynch Vice President of Engineering

Most warehouse facilities have a variety of functions performed beyond just pallet storage:

Picking operations Packaging Maintenance inventory control

Good lighting is essential in a warehouse to promote worker safety, performance and morale.

Good Lighting: Key to Optimum Warehouse Performance

Per OSHA 29 CFR, 5 foot-candles is the minimum lighting level required for general construction areas, warehouses, corridors, hallways and exit ways.

Industry best practice recommends 10-20 foot-candles for active warehouse aisles.

Some factors affecting aisle light levels: Lumen depreciation Lens clarity Aisle occupancy

Warehouse Lighting Requirements

Current Lighting Technologies

High Pressure Sodium

Pulse Start Metal Halide

Fluorescent T5/T8

LED

Legacy < 2000 1995 - present 2003- present > 2010

Input Watts (w) 465 watts 458 watts 342 watts 160 watts

CRI 22 65 80 78

Efficacy (l/w) 97 51 78 62

Lamp Life (hrs) 23,000 18,000 25,000 90,000+

Lumen Depreciation

20%-25% 25%-30% 8% - 10% 8% - 10%

Mercurycontent (mg)

~15 mg ~81 mg ~5mg 0mg

Cost/Fixture $250 - $325 $300 - $375 $350 - $450 $650 - $750

Less input watts required compared to alternatives Less heat load in freezer compared to alternatives Superior Dimming Capability

Dim down to zero percent (off)

Instant on capability From off to full on instantly

Long useful life in freezer environment 90,000+ hours Less re-lamping and recycling costs

Five year warranty

Benefits of LED Technology

ASHRAE defines the instantaneous rate of heat gain from electric lighting as follows:

Q = 3.14 x (W) x (FUT) x FSA x CLFWhere:

Q = Instantaneous rate of heat gain; btu/hr

W = Input Watts

FUT = Lighting Use Factor

FSA= Special Ballast Allowance Factor

CLF = Cooling Load Factor

Lighting Heat Load Calculations

160 watt High Bay LED

Our companies first LED installation Commissioned October 2010 Daily Cost Summary = Electricity + Refrigeration

24/7/365 day operation 23% aisle occupancy (assumed)

25% room occupancy (average)

Case Study #1: Hazleton, PA

Lighting Option Daily Cost ($)

(107) 350 watt Metal Halide (bi-level @ 50%) $65.33/day

(107) 221 watt 6-lamp T8 (bi-level @ 50%) $49.92/day

(107) 160 watt LED (off after 1 minute) $13.72/day

(107) 160 watt LED (off after 30 seconds) $10.02/day

Zigbee wireless network Programmable settings for light output, sensor delay and

inactive state

Data reporting, analysis and energy management Optimize time and occupant programming

Case Study #1: Hazleton, PA (cont.)

Case Study #1: Hazleton, PA (cont.)

Case Study #1: Hazleton, PA (cont.)

Our companies first LED Retrofit Commissioned December 2010 Replaced (133) 400 watt HPS and (234) 400 watt

MH fixture with (360) 160 watt LEDs

Capital Justification based upon: $432,500 capital cost $131,100 annual savings (energy + refrigeration) $44,750 rebate from pubic utility (Oncor) Internal Rate of Return (IRR) = 25.1%

Case Study #2: Fort Worth, TX

LED instant on capability functional down to -22 F. Forklift operators perception is that aisles are brighter

when in fact they are not. Scotopic verse Photopicperception of light.

Operator apprehension when entering a dark freezer. LEDs may interfere with some freezer door motion

sensors. Adjustment may be necessary.

Upper pallet faces not illuminated as well as previous HID fixture.

LED Lessons Learned (so far)

United States Department of Labor, Occupational Safety & Health Administration; Standard 29 CFR; 1926.56(a)

Complete Guide to Modern Warehouse Management; Jenkins; 1990

ASHRAE Fundamentals Handbook; 2009 Illuminating Engineering Society (IES) WideLite; Philips Electronics N.V. Lithonia Lighting; Acuity Brands Company Digital Lumens AlbeoTechnologies

References

Thank You

Use of LED Technology within a PRWGood Lighting: Key to Optimum Warehouse PerformanceWarehouse Lighting RequirementsCurrent Lighting TechnologiesBenefits of LED TechnologyLighting Heat Load Calculations160 watt High Bay LEDCase Study #1: Hazleton, PACase Study #1: Hazleton, PA (cont.)Case Study #1: Hazleton, PA (cont.)Case Study #1: Hazleton, PA (cont.)Case Study #1: Hazleton, PA (cont.)Case Study #2: Fort Worth, TXLED Lessons Learned (so far)ReferencesThank You