ABSTRACT
Introduction For decades, two factors have made the use of conventional oil and gas problematic for most countries. One is the fact that they are finite resources. The other is the fact that some of the largest deposits are found in parts of the world which are politically unstable. Government planners from around the world have long worried, in the short run, about supply disruptions, and in the long run, about what will eventually replace oil and gas when they become prohibitively expensive to extract either onshore or off.
