By Mitch WeissASHEVILLE, N.C. -- When the city launched an ambitious plan to slash its carbon footprint, a major obstacle stood in its way: a massive coal-fired plant on the edge of town. After some progress, Ashville decided to take another step -- passing a resolution calling on Duke Energy ( DUK) to reduce its reliance on coal, a move designed to cut carbon dioxide emissions at the company's Asheville Plant. Environmental groups praised the city's action, saying it would move Asheville from coal-fired electricity toward a clean energy future. And with the move, Asheville joined a debate playing in cities across the U.S. over coal-fired plants and their impact on the environment. "It's a dirty energy source," Sierra Club spokeswoman Kelly Martin said of coal. "It takes bold leadership to do this. Cities all over the country are taking similar action. They're saying: 'We don't want to get our electricity from coal.'" Duke Energy spokeswoman Erin Culbert said the company has been has been working closely with Asheville for years to reduce the city's carbon footprint. But the Asheville plant will continue using coal to generate electricity. "Until there is a practical way to replace the generation from that coal-fired plant, there really aren't a number of alternatives," Culbert said. And she criticized the Sierra Club, saying it misrepresented the city's resolution. "I think it's certainly one more indication that there is a national war on coal," Culbert said. In a way, Asheville's resolution is symbolic. The state -- not municipalities -- regulates utility companies. The city can't force Duke to stop using coal at the Asheville Plant. Still, supporters say it's a meaningful step as the region grapples with the threat of climate change. Scientists assert that coal plants are the major source of carbon dioxide emissions, the primary cause of global warming. For years, environmental groups, including the Sierra Club, have pushed utility companies to transition from coal to clean renewable energy sources, like solar. The groups have started campaigns in communities across the country to bring attention to the problem. Some cities -- like Los Angeles; Austin, Texas; and now Asheville -- have taken local action on climate change.