1 Analysis of cost-environmental trade-offs in biodiesel production incorporating waste 1 feedstocks: a multi-objective programming approach 2 Carla Caldeira* ,a,b,1 , Fausto Freire a , Elsa A. Olivetti c , Randolph Kirchain d , Luís Dias b,e 3 a ADAI-LAETA Department of Mechanical Engineering, University of Coimbra, Polo II, Rua Luís 4 Reis Santos, 3030-788 Coimbra, Portugal 5 Email: caldeira.carla@gmail.com; fausto.freire@dem.uc.pt 6 7 b INESC-Coimbra University of Coimbra, Polo II, Rua Sílvio Lima 3030-290 Coimbra, Portugal 8 9 c Department of Materials Science & Engineering, Massachusetts Institute of Technology, 77 Massachusetts, Cambridge, MA 02139, USA Email: elsao@mit.edu 10 11 d Materials Systems Laboratory, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA Email: kirchain@mit.edu 12 13 e CeBER and Faculty of Economics, University of Coimbra, Av Dias da Silva 165, 3004-512 14 Coimbra, Portugal 15 Email: lmcdias@fe.uc.pt 16 17 18 1 Present address: Joint research Centre of the European Commission, Directorate of Sustainable Resources, Bioecomomy Unit, Ispra, Italy