Anaerobic digestion often generates 鈥榖iogas鈥?- an approximately 3:1 mixture of methane and carbon dioxide - which has been known to be a 鈥榗lean鈥?fuel since the late 19th century. But a great resurgence of interest in biogas capture - hence methane capture - has occurred in recent years due to the rapidly growing spectre of global warming. Anthropogenic causes which directly or indirectly release methane into the atmosphere, are responsible for as much as a third of the overall
additional global warming that is occurring at present. Hence the dual advantage of methane capture - generating energy while controlling global warming - have come to the fore.
This paper presents an overview of the natural and the anthropogenic sources that contribute methane to the atmosphere. In this context it underscores the urgency with which the world must develop and enforce methods and practices to enhance methane capture.