By Ben Lefebvre Of DOW JONES NEWSWIRES HOUSTON -(Dow Jones)- The U.S. Department of Energy said Friday it has authorized Cameron LNG to export liquefied natural gas, opening the door wider for U.S. natural gas companies to send their bounty overseas. The permit allows Cameron, a wholly owned subsidiary of Sempra Energy (SRE), a California-based natural gas distribution and marketing company, to ship up to 1.7 billion cubic feet a day of LNG from its facility in Cameron Parish, La., to countries possessing free-trade agreements with the U.S. The permit was awarded on Jan. 17 and is good for 20 years after the first export shipment. U.S. natural gas producers are hoping to sell the commodity to overseas, where it can command prices much higher than in the U.S. New drilling technologies such as horizontal drilling and hydraulic fracturing have unlocked new sources of natural gas in the U.S., increasing supply and helping to drive prices to a 10-year low. Natural gas futures were $2.39 Friday afternoon, nearly $2 lower year over year and down from nearly $14 in July 2008. A Sempra spokeswoman said the company is still waiting for federal permission to export LNG to any country that doesn't have a free trade agreement with the U.S. -By Ben Lefebvre, Dow Jones Newswires; 713-547-9201; ben.lefebvre@dowjones.com