Energy technology innovation (ETI) is widely considered crucial to both secure affordable energy supplies and cater climate goals. ETI does however not happen in vacuum. Rather, it is subject to a complex interplay between the public sector, private actors and the surrounding institutional environment. This research project focuses on the role of governance and regulation in fostering or preventing energy technology innovation. It assesses a recent technological break-through originating from the US with potentially significant repercussions for Europe: shale gas. Shale gas technology allows generating vital energy supplies domestically by at the same time replacing coal fired power plants, thus reducing carbon emissions. A nascent sector, shale gas provides a unique opportunity to explore the evolvement of regulatory regimes in a new industry; the way how actors and environments play out in different national contexts; and the opportunities and obstacles surrounding technology transfer from one regulatory regime to the other. The project contributes to the academic literature on regulatory governance, regimes and policy transfer. Adopting an interdisciplinary and mixed-method approach, it generates country level data on regulatory regimes in energy and provides for rich comparative insights into the cases of the US, Poland, Hungary and Bulgaria. Finally, it allows drawing policy relevant conclusions on the opportunities and limits of policy transfer in European energy regulation.