AUTHOR=Rixhon Xavier , Limpens Gauthier , Jeanmart Hervé , Contino Francesco TITLE=Taxonomy of the Fuels in a Whole-Energy System JOURNAL=Frontiers in Energy Research VOLUME=9 YEAR=2021 URL=https://www.frontiersin.org/journals/energy-research/articles/10.3389/fenrg.2021.660073 DOI=10.3389/fenrg.2021.660073 ISSN=2296-598X