Los Angeles Saves Millions With LED Street Light Deployment
Next month marks the four-year anniversary of the world’s most ambitious LED street light conversion project. On February 16, 2009, Los Angeles Mayor Antonio Villaraigosa and President Bill Clinton announced a partnership under which the city, advised by the Clinton Climate Initiative, would outfit 140,000 street lights with light-emitting diode (LED) fixtures.
Project planners faced daunting logistics. The City of Los Angeles owns and operates the nation’s second-largest street lighting system: 210,000 street lights (including 70,000 decorative street lamps that will be retrofitted in a second phase) anchored along 4,500 miles of illuminated streets.
The scope of the Los Angeles undertaking, combined with results recorded from the tens of thousands of LED units already deployed, should hasten other cities move to LEDs. Street lighting can account for up to 40% of a city’s electricity bill, according to Pike Research.
On January 23, the Los Angeles Bureau of Street Lighting released a status of the LED conversion project. The results: 114,067 units replaced, $5,325,793 in annual electricity savings, and 63.3% electricity savings over the incumbent high-pressure sodium (HPS) street lights.
The anniversary is a good time to take a closer look at the results and lessons learned, with more than 80% of the LED fixtures planned for phase one deployed. The lessons learned are based on a presentation delivered by Ed Ebrahimian, Director, Los Angeles Bureau of Street Lighting, to the IES Street and Area Lighting Conference convened in Miami in September 2012.
1) Energy savings are real: “As the LEDs improve, and the manufacturers develop the technology, the energy savings are being realized and continue to increase,” wrote Ebrahimian. At the outset, city planners estimated LED fixtures would achieve a 40% electricity savings over HPS units; as noted above, the actual savings is more than 63%. In 2008, Los Angeles spent $16 million for the electricity to run its street lights. When the LED retrofit is completed, annual electricity savings should reach $7.5 million.
According to the city, the $57 million project, funded through a combination of energy rebates, the Street Lighting Assessment Fund, and a $40-million loan, will be repaid over seven years through electricity and maintenance savings alone.
2) Maintenance savings are real, too: In 2008, pre-LED roll-out, Los Angeles logged 70,000 street light repair and maintenance events; in FY 2012, maintenance and repair events fell to 46,300. LEDs are longer lived than the incumbent units they replace (10-15 years versus 4-6 years), which means that maintenance should steadily decline as LED units are fully deployed. A remote monitoring system, installed with the LED fixtures, indentifies problems in real time.
LED fixtures also fail at a lesser rate than incumbent technologies. After 36 months of initial operation, for instance, high-intensity discharge (HID) fixtures in Los Angeles recorded an average failure rate of 10%; the average failure rate for LED fixtures, according to the latest figures, is 0.2% (189 of 98,000 installed). At full LED deployment, Los Angeles expects to save $2.5 million annually on maintenance costs.