WASHINGTON -- Former Maryland Gov. Martin O'Malley called Thursday for ending the nation's reliance on fossil fuels by 2050 and doubling energy efficiency within 15 years -- making the environment the focus of one of his presidential campaign's first major policy rollouts.
The ideas, outlined in a USA TODAY op-ed, coincided with the release of an encyclical from Pope Francis, who called for a "bold cultural revolution" to address the threats posed by global warming.
"We have come a long way as a nation in making ourselves more energy independent," O'Malley wrote. "Now is the time to take this progress to the next level -- the future of our country and our planet depends on it."
O'Malley, who is staking out positions to the left of former Secretary of State Hillary Clinton, generally won praise from environmentalists during his two terms as governor. He fought efforts last year to slow a wind energy project planned for Somerset County, vetoing a moratorium on the project approved by state lawmakers who were concerned about the impact on Naval Air Station Patuxent River.
The developer, Pioneer Green Energy, ultimately pulled out of the project this year, citing "unanticipated hurdles and roadblocks."
O'Malley wrote that his administration would expand rules to cover large sources of greenhouses in addition to power plants, would adopt a "zero-tolerance policy" for methane leaks from oil and gas production and would oppose the controversial Keystone XL pipeline.
"I would set a national, cross-sector renewable electricity standard so our nation is powered by 100 percent clean energy by 2050, and a national goal of doubling energy efficiency within 15 years," O'Malley wrote.
"Many states like California and Maryland are already leading the way forward for the United States."
The ideas won praise from billionaire environmental activist Tom Steyer, who has a long history of supporting Clinton.
"By calling for the rejection of the Keystone XL pipeline and a transition to 100 percent clean energy by 2050, Governor O'Malley is presenting real, concrete solutions to climate change that will secure our country's economic security -- and break with the dirty energy politics of the past," Steyer said in a statement.