There has been ever increasing interest in understanding the various aspects of available resources and production, in terms of need and supply, conservation and environmental impacts and so on. From the current energy scenario, it is very clear that there are serious challenges related in achieving energy sustainability and security worldwide. The aim of this book is to present an overview of progress made towards energy sustainability addressing concerns regarding carbon emission and clean energy resources. Keeping this in mind, the book has chapters on all major energy sources which are being utilized at present, along with those having potential prospects for future.