IJGEI is a refereed, international journal providing an international forum and authoritative source of information, analyses and discussions on renewable and non-renewable energy resources, energy-economic systems, energy and environment, international energy policy issues, technological innovation and new energy sources. Since the 1970s, attention has been focused on energy resources in the search for sustainable and environmentally non-destructive economic development. The confrontation of ecological limits to growth is not only a technological challenge. Economic, social and natural sciences must be brought together in new perspectives, responding to the concerns expressed worldwide for ecological, social, economic and political dimensions of sustainability.