Arterial LED Streetlight Conversions:
City Light will continue to improve customer safety by converting street lights on arterial roadways from high-pressure sodium lights to energy-efficient light emitting diodes, or LEDs. The new LED lights support visibility and safety for pedestrians, bicyclists, and drivers..
The City of Seattle sets regulations based on national standards for how much light should be provided on roadways to maintain safe driving conditions and ensure pedestrian safety. As LED technology continues to evolve, City Light will continue monitoring all studies and stay compliant with all standards.
In late March 2015, conversion work began in City of Seattle's arterial roadways within the utility's service areas between Denny Way and 65th Street from Puget Sound to Lake Washington. The work was completed ahead of schedule which allowed the conversion work to move to the next service area between 65th Street and 145th Street. The majority of the area has been completed with the exception of a small number of roadway segments between 85th Street and 135th Street that have yet to be converted to arterial-grade LEDs. The conversion work on these remaining segments will begin in early June 2016.
At the same time, arterial conversion work has started at Denny Way and will proceed south to Brandon Street from I-5 and east to Lake Washington. Depending on progress, additional conversion work may extend south of Brandon Street. It is expected that all City of Seattle arterial roadways will be completed within 2-3 years. Please see the map
for more details.
Benefits of LED Conversion Include:
Schedule and Map of Arterial LED Streetlight Conversions:
- Approximately 48 to 62 percent lower energy consumption
- High-pressure sodium luminaires, most installed in the mid-1980s, are at the end of their useful lives and failing. LEDs will provide better service reliability and lower maintenance costs.
- Reduction in greenhouse gas emissions:
- In manufacturing
- When LEDs are in use
- Fewer service vehicle trips for repairs will mean a reduction of about 20,000 tons of carbon each year
- Replacement of luminaires with LED fixtures will provide three to four times longer field life than high-pressure sodium
- LEDs are not affected by truck and roadway structure vibration
- Better light quality (whiter/cooler color rendering)
- Light quality improves safety because of depth of field and peripheral vision enhancements without distorted color
Residential LED Streetlight Conversions - Completed Late 2014
- Conversion Schedule Index Maps
- Arterial Conversion Progress - HPS Cobra head streetlights to LED streetlights
Seattle City Light converted its residential streetlights from high-pressure sodium lights to light emitting diodes, or LEDs. The decision was made after thorough evaluation and positive results from pilot projects.
Using the US Department of Energy and the Municipal Solid-State Street Lighting Consortium Retrofit Financial Analysis Tool, City Light estimated the simple payback for LED conversion of residential lights at 7.7 years. It will save the City an estimated $2.4 million in annual energy and maintenance costs.
LED conversion began north of the Ship Canal in 2010 and continued to the north service boundary. In 2012, the project converted residential streetlights from the south service boundary to Brandon Street. The remaining work was completed between Brandon and the Lake Union Ship Canal in late 2014.
LED Streetlights Programs and Information:
DOE Municipal Solid-State Street Lighting Consortium
Former Residential Pilot Area / Customer Surveys
High-pressure Sodium LED Conversion