If the European energy and transport sectors are to meet the 2050 energy and climate policy targets, major sociotechnical change (transition) is necessary. Along with new technologies, changes are required also in other societal functions such as business models and consumer habits. The transition will require cooperation between public and private actors. This paper discusses the socio-technical change towards a 2050 road transport system based on renewable energy. More precisely, it proposes a novel, participatory foresight approach in the context of biofuels in Finland. The participatory and prospective value network analysis outlined in the paper combines elements from the fields of foresight, sociotechnical change on multiple levels and value network analysis. It presents a novel, policy and business-relevant application with a set of practical tools to support development of implementation strategies, but also to boost new business opportunities in the fields of energy and transport.