When looking at the distribution of energy from a geographic viewpoint, the world marketplace can be broadly divided into three areas: industrialized nations, developing nations, and Eastern Europe∕former Soviet Union. This provides a fairly simple breakdown for the discussion of global energy supply from a pipeline perspective. It is also compatible with various other sources of information on the topic, including that of the Energy Information Administration (EIA 2007).
Prior to reviewing the world fossil energy reserves and supply, it is best to first provide an overview of energy usage over the years and as far back as possible and extend it to the future for assessing relevant trends.
In this regard, there have been a number of attempts to look at world energy over a long time span.