Studies are underway into newly-recoverable sources, Ms. Corbeau said. "The gas story is huge. A few years ago the United States was ready to import gas. In 2009 it had become the world's biggest gas producer. This is phenomenal, unbelievable."
The U.S. achieved the change through a technological breakthrough in which firms found a way of using tiny explosions to free gas previously trapped in a common rock - shale. Miss Corbeau said other nations were now rushing to replicate the U.S. success by exploiting gas currently trapped in various types of rock where it was thought to be impossible to access."