The Supplement to vol. 6, 2016 of SCIRES-IT contains the result of CoCoNet (Towards COast to COast NETworks of marine protected areas, coupled with sea-based wind energy potential), a project of the EU Oceans of Tomorrow programme (http://www.coconet-fp7.eu). The European Union requires Open Access to the results of the projects resulting from its support to scientific advancement. This is in full accordance with the policy of SCIRES-IT, an eco-sustainable open-access journal, which joins the main principles of the Berlin Declaration on Open Access with the aims of the International Convention on Biological Diversity. CoCoNet tackled two problems that are closely linked with each other: the protection of the marine environment and clean energy production. Hence, the Supplement is divided into two parts that, together, form a unicum.