Dear Colleagues,

In recent years, challenges related to both climate change and the energy transition need to be faced simultaneously. The energy sector’s transition toward carbon neutrality presents many challenges, such as reducing energy consumption, improving system efficiency, and integrating renewable resources. Due to the favorable ratio of H atoms to C atoms and its higher knock resistance, methane combustion allows reducing CO₂ formation of about 25% and the Global Warming Index of about 15% with respect to gasoline fueling. In this regard, methane-based fuels such as compressed natural gas (CNG) and liquefied natural gas (LNG) are considered transitional fuels in the route to climate neutrality.

In the near future, the role of natural gas in propulsion systems is expected to attract growing interest in the transport sector. With a view to sustainable mobility, both CNG and LNG can be used not only in conventional propulsion systems but also in combination with electric ones. Methane-based hybrid propulsion systems, also considering the limitations of the local infrastructure of fully electric ones, could be a viable solution in energy transition. In this Special Issue, authors are invited to share their knowledge about the natural gas used in conventional/electric hybrid systems and other combined conventional/battery/fuel cell propulsion systems.

Dr. Roberto Ianniello
Dr. Davide Lanni
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Methane is an international peer-reviewed open access quarterly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1000 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

• advanced LNG and CNG combustion concepts
• modeling and experimentation of rotary engines fueled with CNG and LNG
• modeling and experimentation of steam engines, gas turbines, and combined propulsion systems burning CNG and LNG
• modeling and experimentation of hybrid propulsion systems fueled with CNG and LNG
• chemical kinetic mechanisms for CNG and LNG combustion and pollutant emissions prediction
• emission reduction technologies in LNG and CNG engines and hybrid systems
• exhaust–aftertreatment systems for LNG/CNG propulsion systems
• interaction of CNG/LNG combustion systems with supply and support infrastructure