LED Sports Lighting at Duke UniversityCase Study: Williams Field at Jack Katz Stadium

Casey A. Collins, PE, CEMDuke University Facilities Management Department

27 February 2015

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Williams Field at Jack Katz Stadium

Varsity Field Hockey competition & practice

Intramural & recreational events

Host Site of the 2014 ACC Field Hockey Tournament

Big Problem: Not Enough Light for Competition or

Videography

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Project Execution – How to Improve Light?

Project Decision Milestones:– Add HID or convert to LED?– Any structural issues with existing

poles?– Very tight timeline – less than 3

months to do something Technical Issues:

– Energy reduction– Longevity/Reliability– Siting – light trespass issues– Power quality & surge protection

Economic Issues– Maintenance savings primary– Energy savings secondary (low

electric power rate)– Installation Costs– Life Cycle Cost checks

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Sighting / Neighborhood Concerns

• Williams Field located in an urban neighborhood setting

• Light Trespass and glare are a major concern

• Adjacent to Duke East Campus are Residential & Mixed Use/Retail areas, and main N-S corridor through Durham

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Lighting – Technical Basics for Evaluation

Color Rendering Index (CRI): how “true” colors appears under an artificial light source

Color Temperature (CCT): The color hue of the light source itself

Efficacy: Lumen output per input Wattage

Illuminance: how much usable light ends up on a surface (foot-candles)

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LED solution are 1000W, but only require 56 lamps for more than 7x illuminance

What Does LED Lighting Mean For Duke?

Maintenance Savings: $6K/yr

Energy Savings: 40-50%

Increased Operational FlexibilitySatisfied Coaches & Players

Before Lighting Retrofit: 9 foot-candles After Lighting Retrofit: 75 foot-candles

Happy Broadcasters

Existing Lights were 1000W metal halide lamps, 88 across 6 poles

LED solution avoided an additional 55 MH lamps to increase illumination, and avoided pole redesign due to structural issues

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What’s Next?

Questions & Discussion