At a Glance

Last week, Las Vegas announced that it has achieved its goal of switching to exclusively renewable energy.Las Vegas set the goal nearly a decade ago, and the switch is expected to save the city about $5 million annually.

There's certainly one thing that's clean in Sin City: Its energy.

Las Vegas has officially reached its goal of running all city buildings and parks entirely off renewable energy, the city announced a week ago. According to the Las Vegas Review-Journal, it's a goal , and authorities are overjoyed to see a guarantee fulfilled.

"When we say something’s going to happen, it’s going to happen," Mayor Carolyn Goodman told the Review-Journal.

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The Las Vegas Strip is shown behind solar panels during a dedication ceremony to commemorate the completion of the 102-acre, 15-megawatt Solar Array II Generating Station at Nellis Air Force Base on Feb. 16, 2016 in Las Vegas, Nevada.

(Ethan Miller/Getty Images)

The move to renewable energy has saved the city an estimated $5 million annually, the report added. The project has included the installation of solar panels at many city offices and parks, but because space is so limited, additional solar facilities have been built in the Eldorado Valley, the report added. This gives the city as many options as possible to capture the power of the abundant sunlight that shines down onto the desert.

To achieve their goal, Vegas didn't stop at ordinary energy generators like solar arrays or hydropower from the Hoover Dam. The city leaped to the forefront of innovation, going as far as to install smart street lights who walk the Las Vegas sidewalks, according to Engadget.

Popular Mechanics said last week's announcement means Las Vegas , surpassing Burlington, Vermont, which completed its switch in 2014.

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