The literature review presented here soon makes clear how diverse is both the field of study and its analysis. There is no unequivocal definition of community energy, nor are there a clearly delineated set of theories of community energy. Whilst groups of people have been pursuing community energy initiatives for decades, it is only in recent years that this activity has been resurgent and salient in the eyes of policy and research. As such, dialogue between different research insights and the forming of an overall picture is still in its infancy. However, the diversity, dynamics and context sensitivity of community energy suggests any comprehensive theory or picture of the field will remain elusive. Rather, what is available is a rich body of work that is of more or less relevance depending upon ones research and practical interests in community energy over time. In our case, we have related the literature to our concern for sustainable energy innovation in grassroots settings.