Energy transition pathways to a low-carbon Europe in 2050: the degree of cooperation and the level of decentralization by del Granado, PC, Resch, G, Holz, F, Welisch, M, Geipel, J, Hartner, M, Forthuber, S, Sensfuss, F, Olmos, L, Bernath, C, Lumbreras, S, Kranzl, L, Mueller, A, Heitel, S, Herbst, A, Ramose, A, Wilson, C