The incorporation of renewable energy sources to the market has brought a new golden era for process synthesis with challenges and opportunities. In this work, we give a brief review of the state of the art and then present challenges and future directions in this exciting area. The biggest driver is the rapid improvement in computer technology which greatly increases the number of factors that can be considered during the design process. Thus, some of the key future directions lie in integrating the design process with other aspects of process systems engineering, such as scheduling, planning, control, and supply chain management. In addition, sustainability is now a major consideration. The tools available to address these challenges are limited but we are in a position to develop them based on strong chemical engineering principles following a multidisciplinary approach with contributions from other disciplines including biology, biochemistry, computer science, materials, and chemistry. (C) 2019 Elsevier Ltd. All rights reserved.