LED Outdoor Area Lighting
Outdoor Area Lighting: LED vs. MH or HPS
Light Emitting Diode (LED) lighting for many general outdoor lighting applications, such as to illuminate landscape features, attract shoppers to retail areas, illuminate outdoor sales areas like gas stations and car sales lots, illuminate pedestrian and bicycle pathways in parks and campuses, light athletic fields, and more.
Item ID: 79
Residential, Commercial, Industrial, Agricultural
Technical Advisory Group: 2009 Lighting TAG (#1)
Light is used outdoors at night to illuminate landscape features, attract shoppers to retail areas, illuminate outdoor sales areas like gas stations and car sales lots, illuminate pedestrian and bicycle pathways in parks and campuses, light athletic fields, and more.
LED technology is now competing economically and with good performance in some of these applications, and continues to develop at a rapid pace with performance improvements, increased product offerings, and cost reductions. Numerous products are on the market. Because this is not a one-size-fits-all technology, careful evaluations are required to determine which products will work in specific applications.
Government programs and manufacturers continue to push the development and demonstration of this technology and raise the performance standards to make it easier for potential buyers to obtain the LED products they need. The use of "self-cleaning glass or coatings" on fixtures could reduce the need for cleaning which would make the most of long-life and reduced maintenance claims.
Baseline Description: 70W HPS lamp
Baseline Energy Use: 425 kWh per year per unit
Unit is 70W outdoor high pressure sodium lamp (97W luminaire power), taken from the table from the Gateway project: http://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/gateway_palo-alto.pdf , on 12 hours per day.
Manufacturer's Energy Savings Claims:
Currently no data available.
Best Estimate of Energy Savings:
"Typical" Savings: 57%
Low and High Energy Savings: 40% to 70%
Energy Savings Reliability: 5 - Comprehensive Analysis
The LED replacement lamp is compared to a high pressure sodium (HPS) baseline. To achieve this level of savings as of early 2014, the new lamp would produce fewer lumens than the incumbent technology, but LED outdoor lighting provides a higher color quality and more even light distribution. By taking full advantage of these factors and the inherent directionality of LEDs, equal or better visual acuity can often be achieved with 70% savings in energy.
Energy Use of Emerging Technology:
182.8 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.))
The emerging technology energy use is consistent with a 40W LED light source.
Potential number of units replaced by this technology:
Based on Navigant's 2011 report for U.S. DOE SSL Program, "Energy Savings Estimates of Light Emitting Diodes in Niche Lighting Applications" http://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/nichefinalreport_january2011.pdf
Regional Technical Potential:
0.48 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
It is difficult to pinpoint a typical range of installed costs for this technology because there is no average cost and there are many types of outdoor lighting. At the Federal Aviation Administration Technical Center Gateway Demonstration project, the luminaires cost 25-50% more than the HPS fixtures. LED costs vary widely and, in general, are expected to decrease. Because of the relatively long life of LEDs, life cycle cost analysis should be used when looking at costs.
A Seattle City Light project for 100-150W HPS street light retrofits started when the proposed technology cost $350 per fixture, but the price had dropped to $290, enabling them to expand their scope more rapidly. When Seattle City Light starts a project on arterial streets next year, the expected cost will be $800 per fixture.
Simple payback, new construction (years): N/A
Simple payback, retrofit (years): N/A
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.
As stated in the U.S. DOE’s Energy Efficiency of Outdoor Area Lighting publication, linked below,
“As a new technology, LED luminaires currently cost more to purchase than traditional fixtures lamped with commodity-grade HPS or MH light sources. The reduction in relamping cost and potential power savings with LEDs may reduce the overall lifecycle cost. Economic evaluation of LED outdoor luminaires is highly site-specific, depending on variables including electric demand (kW) and consumption (kWh) rates; labor costs, which may be bundled in a broader maintenance contract for the site; and other options available for the site. LED outdoor lighting demonstrations documented by DOE to date have shown estimated paybacks from three years to more than 20 years, depending on the assumptions and options assessed.”http://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/outdoor_area_lighting.pdf
The GE Lighting website offers a lighting payback calculator that may be helpful: http://www.gelighting.com/na/business_lighting/education_resources/tools_software/outdoor_led_calculator/
Light is used outdoors at night to illuminate landscape features, attract shoppers to retail areas, illuminate outdoor sales areas like gas stations and car sales lots, illuminate pedestrian and bicycle pathways in parks and campuses, light athletic fields, and more. Light Emitting Diodes (LEDs) are being developed for many of these applications, from broad areas to narrow paths. Factors that buyers consider when installing outdoor lighting include a good visual environment, control of unwanted light pollution, and energy efficiency, and LED lighting increasingly offers features that address all of these factors. LEDs perform well in cold temperatures, have long lives that reduce maintenance costs, and are expected to offer many control options in the future.
As stated in the U.S. DOE’s Energy Efficiency and Renewable Energy publication linked below,
“Recent advances in LED technology have resulted in a new option for outdoor area lighting, with several potential advantages over metal halide (MH) and high pressure sodium (HPS) sources. Well-designed LED outdoor luminaires can provide the required surface illuminance using less energy and with improved uniformity, compared to HID sources. LED luminaires may also have significantly longer life (50,000 hours or more, compared to 15,000 to 35,000 hours) with better lumen maintenance. Other LED advantages include: they contain no mercury, lead, or other known disposal hazards; and they come on instantly without run-up time or restrike delay. Further, while MH and HPS technologies continue to improve incrementally, LED technology is improving very rapidly in terms of luminous efficacy, color quality, optical design, thermal management, and cost.” http://apps1.eere.energy.gov/buildings/publications/pdfs/ssl/outdoor_area_lighting.pdf
The Solid-State Lighting Gateway Demonstration Program has a complete report about LED Walkway Lighting: Federal Aviation Administration (FAA) Technical Center, available from: http://www.eere.energy.gov/buildings/ssl/gatewaydemos_results.html
Lightsearch (http://www.lightsearch.com) and Facility Zone (http://www.facilityzone.com/) are search engines where numerous lighting products may be located.
For many outdoor lighting applications, high pressure sodium (HPS) is commonly used because of its relatively long lamp life and high lumens per watt, but its poor color rendering make it less desirable in many applications. Metal Halide (MH) is used where white light is desired, but it has slow strike and restrike times and a relatively short life.
As stated in the U.S. DOE’s Energy Efficiency and Renewable Energy publication linked below, “Current LED product quality can vary significantly among manufacturers, so due diligence is required in their proper selection and use. LED performance is highly sensitive to thermal and electrical design weaknesses that can lead to rapid lumen depreciation or premature failure. Further, long-term performance data do not exist given the early stage of the technology's development. Interested users should continue to monitor available information sources on product performance and lifetime, such as CALiPER test results and GATEWAY demonstration program reports.” http://www.eere.energy.gov/buildings/ssl/outdoor_overview.html
End User Drawbacks:
Adoption of this technology may be hampered by high first costs and unfamiliar product specifications. The development and adoption of standards for performance is ongoing, and the Lighting Facts label program will help potential buyers understand more about the products. Providing incentives to reduce the cost may also help buyers overcome initial resistance. (Links to these programs are provided in Additional Information below.)
Lack of long-term, in-situ performance data may also be a deterrent, but the Gateway Program of the U.S. DOE Solid State Lighting Program is helping to get more monitored products on the street. In addition, the CALiPER program tests lighting performance and compares test results to manufacturer claims.
Warranties of a few years for a product that is expected to last 20 years or more could be seen by some as a lack of confidence in the product.
Some buyers may also be concerned about finding replacements for products that experience premature failure. Especially for white, it may be difficult to match the color of the original with a replacement. In addition, products are evolving so quickly, that by the time a customer needs a replacement, it is likely that the product is no longer manufactured.
This technology is still new, so some disposal considerations still need to be sorted out. Recycling is likely to be the recommended action. However, not knowing how LED waste will be handled could be a drawback to some, so a take back plan by the manufacturer could help deal with that uncertainty.
Another drawback may be LED light color; the bluer white light may not appeal to those who like warmer sources. Also, “white” light varies from product to product and even the same product in different runs.
Operations and Maintenance Costs:
No information available.
The effective life of this technology is expected to be long, 10 to 20 years or more. Most LED lights are rated at approximately 50,000 hours of service. For an application that is on during all dark hours, averaging 12 hours per day, this is about 11.5 years. LEDs tend not to “burn out.” They simply lose lumen output. End of life is defined by when an LED lamp reduces its output to 70% of the original output. It is likely that an improved product will be available before many of these products reach the end of their useful life. The FAA expects over 22 years of service from their installation.
HPS, MH, pulse-start MH, ceramic MH, induction, fluorescent, electron stimulated luminescence (ID #104), high efficiency plasma lighting (ID #80), and compact fluorescent lamps are lighting technologies that compete with the proposed technology.
Reference and Citations:
Bi-level Smart LED Bollard
University of California, Davis
Provides estimates of energy savings and cost data in comparison to both HID and CFL baselines.
Energy Efficiency of Outdoor Area Lighting
Department of Energy, Office of Energy Efficiency and Renewable Energy
Provides energy savings comparisons of multiple bollard technologies.
Demonstration Assessment of Light-Emitting Diode (LED) Roadway Lighting on Residential and Commercial Streets - Host Site: Palo Alto, California
U.S. Department of Energy
Palo Alto demonstration.
Demonstration Assessment of Light Emitting Diode (LED) Street Lighting, Phase III, Continuation - Host Site: City of Oakland California
U.S. Department of Energy
LED Lighting Facts
U.S. Department of Energy
Demonstration Assessment of Light Emitting Diode (LED) Walkway Lighting, Host Site: Federal Aviation Administration, William J. Hughes Technical Center, Atlantic City, New Jersey
U.S. Department of Energy
Adaptive Exterior Lighting Guide
California Lighting Technology Center, CEC PIER Lighting Demonstration
Energy Efficiency & Renewable Energy
Solid-State Lighting GATEWAY Demonstration Outdoor Projects
U.S. Department of Energy, Office of Energy Efficiency & Renewable Energy
Light at Night and Human Health
Energy Efficiency & Renewable Energy
Lighting Research Center
LEDs: A closer look
LIghting Design Lab