AbstractThis paper presents a techno‐economic evaluation of potential Greenfield projects of integrated first‐ and second‐generation sugarcane biorefineries, in which ethanol is converted to bio‐based propylene through metathesis of ethylene with 2‐butene. Two scenarios were tested, considering improvements both in first‐ and second‐generation ethanol production: with and without pentoses fermentation, which increases the amount of ethanol produced. The viability of the proposed propylene production facility was studied through Minimum Bio‐Propylene Selling Price (MBSP), and sensitivity and risk analysis were performed. Results show that, compared to the average propylene prices in recent years, the MBSP (based on the average estimates) would be no more than 85‐90% higher than the price of the conventional fossil‐fuel based product. In addition, three aspects were further assessed: (i) scaling of production plants, (ii) learning effects, and (iii) policies that would result lower capital costs. The results show that the cumulative effect would lead a substantial reduction of the MBSP, leading to a competitive price of 1347 US$/t. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd