LED Outdoor Wall Wash Luminaires
Outdoor Wall Wash Lighting: LED vs. HID or Fluorescent
Luminaires for decorative lighting and highlighting walls of buildings, stages, parks, plazas and commercial building facades.
Item ID: 397
Exterior wall-wash lighting is an application where LED products are beginning to emerge. These wall-wash lights are designed for decorative lighting of buildings, plazas, stages, etc.
Outdoor lighting luminaires employing LED technology are widely available from a number of manufacturers. The U.S. Department of Energy (USDOE) is encouraging research, development and market penetration of the technology and is providing resources for developing objective, updated information about the technology. Of the almost 22,000 products listed in the USDOE LED Lighting Facts database as of December 2014, over 6,400 (29%) are commercial outdoor products. Of these outdoor products, there are about 50 identified specifically as wall-wash luminaires with an average efficacy of over 70 lumens/watt.
Energy savings over traditional outdoor wall-wash lighting may be significant—up to 30-75%, depending on design light levels, technology and controls. Lamp life could be significantly longer than other systems in use, making this product especially good in hard-to-access locations. The white light is available in a range of color temperatures. Because of the directionality of LED light sources, LED wall-wash lighting can accurately and efficiently illuminate the desired area. Additionally, the USDOE predicts continued improvement in efficacy and decline in price for LED lighting.
Baseline Description: 70W MH lamp
Baseline Energy Use: 312 kWh per year per unit
Assuming 95 W (input watts) * 3285 hr/yr / 1,000 W/kW = 399 kWh/yr. Operating hours at 9 hr/day for building exterior lighting. (Navigant, 2012 Pg Table 4.29, pg 54)
Manufacturer's Energy Savings Claims:
Currently no data available.
Best Estimate of Energy Savings:
"Typical" Savings: 50%
Low and High Energy Savings: 30% to 80%
Energy Savings Reliability: 6 - Approved Measure
Savings range 30-80%. Typical energy savings is based on replacing the baseline 70W (95W input) MH with an LED fixture consuming 48 W. The assumed replacement was developed based on a review of wall wash products listed on the LED Lighting Facts database with similar, but slightly lower, lumen output. Typically, LED fixtures can provide suitable lighting performance with lower lumen output than the traditional source due to the directional nature of LED lighting.
Energy Use of Emerging Technology:
156 kWh per unit per year
Energy Use of an Emerging Technology is based upon the following algorithm.
Baseline Energy Use - (Baseline Energy Use * Best Estimate of Energy Savings (either Typical savings OR the high range of savings.))
Potential number of units replaced by this technology:
Assuming Northwest potential of 4% of national potential (Northwest is about 4% of the population of the U.S.). Assuming national potential of 10% of flood lighting units, based on Navigant's 2011 report for U.S. DOE SSL Program, (Navigant , 2011).
Technical Potential = 4% * 10% * 43,200,000 = 200,000 units.
Regional Technical Potential:
0.03 TWh per year
Regional Technical Potential of an Emerging Technology is calculated as follows:
Baseline Energy Use * Estimate of Energy Savings (either Typical savings OR the high range of savings) * Technical Potential (potential number of units replaced by the Emerging Technology)
Installed first cost per: unit
Emerging Technology Unit Cost (Equipment Only): $390.00
Emerging Technology Installation Cost (Labor, Disposal, Etc.): $68.00
Baseline Technology Unit Cost (Equipment Only): $290.00
Costs for wall wash luminaires were developed from an Internet pricing review. The price premium for LED wall wash luminaires as compared to metal halide is about 30%, although prices for LEDs are expected to continue to decline.
Labor costs to replace an existing wall wash with a new LED are estimated at $68, assuming 0.75 hr at $90/hr.
Simple payback, new construction (years): 7.1
Simple payback, retrofit (years): 32.6
Cost Effectiveness is calculated using baseline energy use, best estimate of typical energy savings, and first cost. It does not account for factors such as impacts on O&M costs (which could be significant if product life is greatly extended) or savings of non-electric fuels such as natural gas. Actual overall cost effectiveness could be significantly different based on these other factors.
Reference and Citations:
LED Lighting Facts
U.S. Department of Energy
Energy Savings Estimates of Light Emitting Diodes in Niche Lighting Applications
U.S. Department of Energy, Building Technologies Program
DesignLights Consortium Qualified Products List
DesignLights Consortium, Northeast Energy Efficiency Partnerships, Inc.
Solid State Lighting Program
U.S. Department of Energy, Office of Energy Efficiency & Renewable Energy
Demonstration of LED Retrofit Lamps Host Site: Smithsonian American Art Museum, Washington, DC
PNNL for DOE Solid State Lighting Program
2010 U.S. Lighting Market Characterization
U.S. Department of Energy Building Technologies Program
Resources for Outdoor SSL Applications
U.S. Department of Energy, Federal Energy Management Program