In this seminar I will share my view on how the energy system might evolve: What is easy? What is difficult; What do we need to do or decide today? What can wait? All of this is ambiguous and widely differing views can sometimes result from subtly different assumptions about environment, technology and society. Scenarios are a useful way to explore these uncertainties and the resulting outcome-space. I will speak from a background in Shell (1988-2016) with strong involvement in scenario making, and one year in academia with fresh insights in many things, including Solar fuels and nuclear fusion – two topics close to heart at DIFFER.