Comparative evaluation of sixteen alternative fuels for thermal applications
Thermal Science and Engineering Progress, vol.77, 2026 (SCI-Expanded, Scopus)
- Publication Type: Article / Article
- Volume: 77
- Publication Date: 2026
- Doi Number: 10.1016/j.tsep.2026.104876
- Journal Name: Thermal Science and Engineering Progress
- Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Compendex, INSPEC
- Keywords: Biofuels, Energy, Environmental impact assessment, Fuels, Hydrogen, Life cycle assessment, Sustainability, Thermal engineering
- Yıldız Technical University Affiliated: Yes
Abstract
The escalating climate crisis and concerns over environmental degradation have intensified the global search for sustainable alternatives to conventional fossil fuels. This paper presents a comprehensive, comparative life cycle assessment (LCA) of sixteen alternative and two conventional fuels to quantify and contrast their environmental performance. The fuels assessed in this study include diesel, gasoline, natural gas, propane, liquid petroleum gas (LPG), liquefied natural gas (LNG), kerosene, naphtha, methane, ethanol, methanol, butanol, soy biodiesel, biogas, hydrogen, synthetic gas, formic acid, and dimethyl ether (DME). The analysis is conducted using a standardized well-to-wheel (WTW) system boundary, adhering to ISO 14040/14044 guidelines. The functional unit for comparison is defined as 1 MJ of delivered fuel energy. The CML-IA baseline (v3.06) midpoint methodology is employed within the SimaPro 9.5 software environment, utilizing the Ecoinvent 3.9 database. The eight key environmental impact categories are utilized to assess the selected fuels. The findings reveal a stark contrast between fossil-derived fuels and renewable alternatives. Fossil fuels, particularly diesel global warming potential (GWP: 2.90 kg CO2-eq/MJ) and gasoline (GWP: 2.47 kg CO2-eq/MJ), consistently exhibited the highest environmental burdens across nearly all impact categories, including GWP, ADP, toxicity, and acidification. In contrast, renewable fuels demonstrated significantly superior performance. Hydrogen (produced via renewable pathways) has emerged as the most sustainable option, with a near-zero impact profile across all categories (GWP: 0.003 kg CO2-eq/MJ). Biogas (GWP: 0.53 kg CO2-eq/MJ) and formic acid (GWP: 0.29 kg CO2-eq/MJ) have also showed exceptionally low environmental footprints. Consequently, no single fuel represents a flawless solution, but a multi-criteria assessment reveals clear leaders. Hydrogen, biogas, and formic acid consistently emerge as the most promising sustainable options for decarbonizing the energy and transport sectors.