Penrose triangles of fossil-to-bio-based transition

Transition within the chemical industry from fossil to green feedstocks is a complex process characterized by the generation of commercially viable feedstock–process–product triangles. The research in this area encompasses a great diversity of relevant topics. A number of those topics have been addressed within this volume of Faraday Discussions and are summarized in this paper. They are categorized and discussed along with seven general questions arising from the feedstock–process–product triangles. Opportunities are identified that should make more of these triangles technically and economically feasible. The future role of renewable electricity as the primary energy source for the bio-based industry is emphasized.