The economic part of the studies aim at analysing energy systems, energy markets and technology, studying the dynamics of technological development, and its implications for fusion (dependence of production costs on plant engineering, learning and experience, internalisation of externalities, development of the demands, regulations and policies), and preparing, possibly together with stakeholders of other energy options, fusion relevant sustainable energy scenarios with models that incorporate the 4 E´s: economy, engineering, energy, and environment.