Mukesh Ambani, chairman of the world's largest refinery, Reliance Industries Ltd, has said the US' development of shale oil and gas will make the country energy-independent as early as 2018, reported emBloomberg./em For many decades, we have heard that the US will be independent of foreign imports of energy, Ambani was quoted as saying in an interview with emCNN/em's Fareed Zakaria . Realistically, it is my judgment this will happen in the next five to seven years. [caption id=attachment_620292 align=alignleft width=380