First generation biofuels are widely available because the production technologies are well developed. However, growth of the raw materials conflicts with food security, so that first-generation biofuels are not so promising. The second generation of biofuels will not compete directly with food but requires several energy intensive processes to produce them, and also increases land-use change, which reduces its environmental and economic feasibility. The production of third-generation biofuels avoids the issues met with first-and second-generation biofuels, namely food-fuel competition, land-use change, etc., and is thus considered a viable alternative energy resource. On all dimensions of sustainability (environmental, social and economical), a life cycle assessment approach is most relevant to avoid issues in problem shifting. The utilization of organic waste and carbon dioxide in flue gases for the production of biomass further increases the sustainability of third generation biofuels, as it minimizes greenhouse gas emissions and disposal problems. (C) 2011 Society of Chemical Industry