Aspen, Colorado is best known for its ritzy ski slopes, but it also just became the third American city to run fully on renewable energy.
The city joins the ranks of Greensburg, Kansas and Burlington, Vermont, which went 100 percent renewable in 2013 and 2014, respectively.
Aspen made the switch from 75 percent to fully renewable in August when it signed a contract with the Municipal Energy Agency of Nebraska, a wholesale electric energy provider. This allowed wind power to take the place of coal, former city project coordinator Will Dolan told the Denver Post.
The rest of Aspen’s energy sources are domestic, too: The city receives wind energy from Nebraska and South Dakota and hydropower from within Colorado itself.
Although Aspen has a year-round population of fewer than 7,000, its green efforts have been underway for over a decade. In 2005, they created the Canary Initiative, which identifies mountain communities like Aspen as "canaries in the coal mine" because they are affected by climate change before other locations.
The city frames its achievement as part of a larger citywide goal to reduce Greenhouse Gas Emissions 30 percent below 2004 levels by 2020 and 80 percent below 2004 levels by 2050.
The area's transition has been facilitated by the steep decline in price of renewable energy source, including solar, geothermal and wind, over the last few years.
The three other cities that have successfully made the clean energy leap present lessons for other American cities that want to follow their lead.
All these areas have high-level direction from their municipal government. For instance, the mayor of Greensburg devised a "master sustainability plan" to go fully renewable after the town was devastated by a tornado in 2007. It achieved that goal in just six years thanks to parallel infrastructure projects like the Greensburg Wind Farm.
Greensburg is even smaller than Aspen, with about 850 residents, which likely helped it make the switch so swiftly. But Burlington, the third fully renewable city, is actually the largest city in Vermont, with a population of more than 42,000.
Burlington is part of a statewide movement in Vermont to get 90 percent of all its energy from renewable sources by 2050, as reported in the Boston Globe. As in Aspen, utility officials in the notably liberal city of Burlington started planning for 100 percent renewable energy over a decade ago.
If recent government investments are any indication, it will be even easier for American cities to go renewable. As HuffPost reported this month, the U.S. just made its largest-ever investment in solar energy in Arizona. And due to the Obama administration’s regulations, fossil fuels are getting more expensive by the day.
As Aspen energy official David Hornbacher told the Aspen Times, the city has shown how “a small, progressive community can work together to be a pathway for others…[and] we hope we can inspire others to achieve these higher goals.”
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