You know you’ve hit the big time when New York City sings your praises. In October, Mayor Michael Bloomberg announced a plan to retrofit the streetlight network with LEDs.

As part of the Bloomberg administration’s PlaNYC, a long-term sustainability program that aims to reduce greenhouse gas emissions from city government operations by 30 percent by 2017, the city’s Transportation Department will replace all 250,000 streetlight fixtures with LEDs.

The city expects LEDs to last up to 20 years before needing replacement, in contrast to the six years it currently gets out of high-pressure sodium lights, producing an 80 percent savings for the city on maintenance costs. Calling it a “necessary feat,” Bloomberg touted the project as the largest of its kind in the country, and he expects it to save the city $6 million in energy and $8 million in maintenance a year.

The project caps a major effort already underway since 2011. Thousands of LEDs have been installed along major roadways, bridges and pedestrian paths in Central Park. That effort was launched by two separate studies conducted by the city in 2009. One study found that LEDs provided energy savings of up to 50 percent, and the other study showed 80 percent.

The new project will be completed in three phases, each installing about 80,000 LEDs at a time across the city’s five boroughs. The first phase is expected to be completed by December 2015. The final phase will be completed in 2017.