Greenpeace activists scaled a huge cooling tower at a major coal-fired energy plant in central Poland Tuesday demanding the country use more renewable energy, Poland's TVN24 news channel reported, according to dpa. Activists climbed the cooling tower at the Belchatow electrical facility and painted "Stop CO2" in huge black letters on it. A Greenpeace banner was also hoisted on the massive tower. "We are demanding a change in energy policy so that electricity plants such as the one in Belchatow are discontinued and a switch is made to renewable resources which protect the climate," Greenpeace spokesperson Magdalena Zowsik told TVN24. She claims the Belchatow plant, the largest single producer of CO2 in Poland, emits more carbon dioxide per year than do small EU states Estonia and Slovenia combined. A spokesperson for the Belchatow facility, however, claims special filters used at the facility mean it operates in line with EU norms for greenhouse gas emissions and is therefore more environmentally friendly than Greenpeace activists contend. A member of the European Union since 2004, Poland is heavily reliant on coal-fired plants for electrical energy supplies to its 38 million people. "We want to make politicians understand that climate change and global warming have their causes in these kinds of facilities," Greenpeace's Zowsik said. Six Greenpeace activists detained by police at the site were later charged with disturbing the peace and could face up to a year in prison. Ten other activists who painted the "Stop CO2" emissions on the tower will face vandalism charges carrying a penalty of up to five years behind bars.