Los Angeles swapped 140,000 of its 210,000 streetlights for LEDs over four years; energy use fell 63%, well past the 40% promised, saving $7 million a year on a $57 million programme

While cities often come up with greener plans, few can back them up with figures as convincing as these. According to a U.S. Department of Energy case study on Los Angeles’s streetlight replacement, the new LED streetlights were expected to cut energy use by about 40 percent. However, in reality, the decrease was much higher, 63%, and the retrofit involved 140,000 of the 210,000 streetlights in Los Angeles between 2009 and 2013.

Building the largest LED retrofit in the country

Los Angeles has the second-largest street lighting network in the United States, covering about 4,500 miles of streets. Retrofitting such a large number of fixtures on a neighborhood-by-neighborhood basis could be quite time-consuming. According to the Los Angeles Bureau of Street Lighting, Los Angeles’s 2013 retrofit of more than 140,000 standard cobra-head lights was one of the largest projects of its kind undertaken by any U.S. city at the time. The fixtures replaced the familiar old high-pressure sodium bulb, the kind that gives streets their orange hue.


Why the real numbers beat the projected ones

The problem with sodium lights is that they lose a lot of energy as heat. By contrast, LEDs convert more of their energy into light and less into heat, which helped drive savings above projections. However, there was yet another factor at play. In a DOE-produced interview, Ed Ebrahimian, director of the Bureau of Street Lighting, said that when the retrofit was first being planned, fixtures cost about $700 apiece, but by the time the program actually launched, the price had already dropped to about $400. Energy savings are the figure most often cited, but they are not the only savings the project produced. The Bureau of Street Lighting has also pointed to reduced maintenance needs for the whole system. Because LEDs last significantly longer than the high-pressure sodium lamps they replaced, the need for maintenance is low. In a project worth $57 million, the Bureau and independent reporting on the retrofit indicate the total savings in energy and maintenance would pay for itself in about seven years.

The environmental gains were just as notable as the financial ones. The first phase of the retrofit cut carbon emissions by an estimated 47,583 metric tons a year, equivalent to removing about 10,000 cars from Los Angeles roads annually. By the time Phase II wrapped up, the completed system was delivering 64% energy savings, or 114 gigawatt-hours saved each year, while cutting emissions by roughly 67,000 metric tons. That scale of carbon reduction is rare for a project centered on something as ordinary as a streetlight bulb.

Brighter streets, and what the research says about safety

City officials at the time said some residents assumed extra lights had been installed, when in reality, the same fixtures were just doing a better job. That claim is hard to prove on its own, but it is consistent with research on street lighting and crime. A randomized study titled ‘Can deterrence persist? Long-term evidence from a randomized experiment in street lighting,’ published in Criminology & Public Policy, led by economist Aaron Chalfin and colleagues, found that outdoor nighttime index crimes in public housing facilities in New York City fell by at least 36% in those neighborhoods where additional lights were introduced. The authors say the reduction persisted over time and did not come with a later increase in arrests, suggesting the crime drop was not just a displacement effect from stricter enforcement. However, the New York study involved adding new light towers to darker areas, not swapping an existing sodium fixture for a brighter LED one as Los Angeles did; so, along with the fact that it was conducted in a different city, it cannot show the exact effect of LA's retrofit. Still, it helps explain why cities now take this approach to lighting.

What other cities can take from this

If your city lights up in the familiar orange hue, Los Angeles offers a quiet sneak peek of what can happen when a retrofit is done at scale. Smaller cities could also benefit, since they would have fewer fixtures to replace. The broader lesson is not just about streetlights; it's a reminder that unglamorous infrastructure upgrades, the kind that never trend online, can quietly save millions of dollars while making everyday city life a little better.