It is a great pleasure to welcome you to the 2nd International Conference on Energy & Environment: bringing together Engineering and Economics, ICEE, in Guimarães, Portugal, June 18-19, 2015.The conference is organized by the School of Engineering, University of Minho and the School of Economics and Management, University of Porto.ICEE brings together leading academic scientists, researchers and scholars from the energy and environment science community to interchange knowledge, to discuss and to disseminate new ideas towards a low-carbon, sustainable future. Indeed, energy and environment transition issues require much more than pure technology knowledge. Instead, they involve processes of technological transfer where economics, social sciences, and even politics play decisive roles.