Introduction of the Special Issue on SMARTCATs COST Action

The fulfillment of societal energy needs is currently faced with several constrains that are swiftly and continuously changing the possible scenarios of the near future energy market. If global warming is accelerating and, in turn, hasten the request of renewable, green energy systems, on the other hand, geopolitical equilibria keep the grid strictly anchored to wellestablished, traditional energy production systems. This hinders the drastic reduction of greenhouse gas emissions, which is needed to meet the strict goals fixed over the years. Energy carriers coupled with advanced combustion technologies are synergistic twin strategies that can satisfy the two apparently antithetic requirements of geo-political and environmental sustainability and security. Indeed, energy carriers represent a wide category of molecules, including both conventional and bio-derived fuels as well as molecules used to store both conventional and renewable source energy surplus as in power to fuel options. At the same time, to efficiently exploit the large class of locally available energy carriers, fuel-flexible advanced combustion technologies are strongly needed. From this standpoint, a smart energy carrier (SEC) identifies with molecules (derived from standard, alternative, or unconventional sources), locally produced or made available, that can be safely and cleanly transformed into energy by means of the best available combustion technologies. SMARTCATs COST Action (www.smartcats.eu) is a collaborative network of research and academic institutions as well as companies from 30 countries, set up within the Cooperation in Science and Technology European framework (www.cost.eu) under the umbrella of the Horizon 2020 Programme. SMARTCATs is focused on the investigation on chemistry and technologies of SECs: the chemistry and kinetics of oxidation/pyrolysis of energy carriers, the potential formation of new noxious species and the tools needed for process study, monitoring, and control, and the technologies needed for SEC practical use are the key topics driving collaborations and share of facilities, tools, and people actively working in the field. This special issue includes a selection of papers, from fundamental to applied research, discussing results presented at the third SMARTCATs general meeting held in Prague at J. Heyrovsky ́ Institute of Physical Chemistry of the Czech Academy of Sciences. The meeting was organized by Prof. Zdeneǩ Zelinger of the J. Heyrovsky ́ Institute with the collaboration of Dr. Jirǐ ́ Vav́ra from the Czech Technical University in Prague and Dr. Vaćlav Nevrly ́ from the VŠBTechnical University. We thank the Energy & Fuels Editor-in-Chief for giving SMARTCATs participants this opportunity and for taking care of the reviewing process of submitted papers. The papers accepted for publication on this special issue were selected following the traditional high standard reviewing process of the journal. Mara de Joannon Pino Sabia Istituto di Ricerche sulla Combustione, Consiglio Nazionale delle Ricerche, 80125 Napoli, Italy George Skevis Chemical Process and Energy Resources Institute, Centre for Research and Technology Hellas, 57001 Thessaloniki, Greece