Local governments will play an important role in the transition towards fully renewable energy systems. In order to develop new roles for themselves in climate and energy planning, they have to be creative and find new ways of acting within existing regulatory frameworks. The objective of this paper is to explore the kinds of arguments and discussions local key actors use and encounter when developing innovative activities. We study two exemplary cases using a qualitative research approach based on interviews with key informants: a municipality-owned nearshore wind farm, and a local funding scheme for energy-efficiency refurbishment in single-family houses. Our findings indicate that i) innovative projects grow out of the momentum of previous visions and experiences; ii) key actors balance ‘green’ and economic arguments in order to gain project approval; and iii) innovative projects can sometimes only be realized by drawing on resources from outside the municipal sphere. Even though committed key actors may be successful, it is worth considering how the grip of narrow economic motives can be loosened in order to support the local experimentation and innovation that will become more and more important in green energy transitions. •Local authorities need to experiment towards smart energy systems.•Unprecedented local energy action is risky and needs convincing arguments.•Key actors balance wide and narrow societal commitments to promote new initiatives.•Space is needed for wider societal commitments in local experiments in the future.