At the turn of the millennium high expectations were connected to fuel cells. Various energy companies, politicians as well as many initiated public-private partnerships were of the same opinion: a Hydrogen Economy would combine economic growth with environmental concerns and security of energy supply and that was crucial for the future. But this was not the first time there were high expectations on fuel cells and in this article we map the changes 1978-2005 from energy transformers over to batteries and then end up as energy sources. We take their heterogeneous character for genuine and analyse how they are part of different discourses by following the construction of them by actor-networks. The article discuss how fuel cells and hydrogen had to change to fit together with the discourse of ecomodemisation, or to put the question differently, we analyse which aspects of the heterogeneous fuel cell technology are emphasised when connected to the iscourse of ecomodernisation. This analysis and the conclusions drawn contribute to a better understanding of technological change and also show important lessons for practitioners. Copyright (c) 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.