Advanced biofuels: The evolution of international research networks

Alternative fuels for transportation are gaining momentum in the global market. Ethanol has been the most used biofuel as an additive and as a substitute for gasoline in a number of countries. Current technology to produce ethanol based on sugar and starch crops creates price imbalances in the food market and cannot supply a sustainable industry of ethanol in the long term. Second generation technologies based on cellulosebased feedstocks use non‐edible crops and have a positive energy balance. Notwithstanding, they are not yet economic at the industrial level, requiring investment in Research and Development (R&D) to help overcome technological barriers. Many countries recognise the value of collaboration to increase benefits and reduce costs of research, and some of them have in place policy instruments to promote this practice. Given the policy relevance, multidisciplinary characteristics of biofuels, and increasing incentives towards international cooperation, the monitoring of the evolution and patterns of international collaboration in R&D is in place. We map the evolution of the global scientific activity of research on cellulosic ethanol. We carry out a bibliometric analysis by building a publication dataset drawn from the ISI Thompson Science Citation Index database covering the period between 1970 and 2006. We identify the most productive institutions and countries, their historical evolution and interaction patterns.