<Li> Natural gas was not a viable portion of US energy as of 2008, since we may have peaked in domestic reserves: U.S. imports of natural gas from Canada tripled since 1973 . <Ol> <Li> However, US gross natural gas production set new all - time record highs each year from 2007 through 2013, due in part to new methods to extract Shale gas . Despite record withdrawals, the volume of US proved reserves still in the ground also stands at an all - time high, according to reserve data for the end of 2011 . US net imports of natural gas peaked in 2007, then declined rapidly, and in 2013 were 60 percent below 2007 . </Li> </Ol> </Li> <Ol> <Li> However, US gross natural gas production set new all - time record highs each year from 2007 through 2013, due in part to new methods to extract Shale gas . Despite record withdrawals, the volume of US proved reserves still in the ground also stands at an all - time high, according to reserve data for the end of 2011 . US net imports of natural gas peaked in 2007, then declined rapidly, and in 2013 were 60 percent below 2007 . </Li> </Ol> <Li> However, US gross natural gas production set new all - time record highs each year from 2007 through 2013, due in part to new methods to extract Shale gas . Despite record withdrawals, the volume of US proved reserves still in the ground also stands at an all - time high, according to reserve data for the end of 2011 . US net imports of natural gas peaked in 2007, then declined rapidly, and in 2013 were 60 percent below 2007 . </Li> <Li> In the absence of breeder reactors or fusion reactors, nuclear power plants aren't a solution to energy independence either, since uranium must be imported: currently, 80% of U.S. uranium is imported, mainly from Russia and Canada . </Li>

When was the united states considered oil independent nation