The transition away from traditional petroleum gasoline is unlikely to rely on a single replacement fuel, but rather a diversified mix of advanced energy sources tailored to specific transportation applications. Battery electric vehicle technology is rapidly capturing the passenger car and light-duty transit market due to improving battery chemistries and expanding charging infrastructure. Meanwhile, heavy-duty commercial trucks, maritime shipping, and aviation are turning to alternative energy carriers such as hydrogen fuel cells, renewable natural gas, synthetic e-fuels, and sustainable aviation fuels derived from biomass or captured carbon dioxide. These solutions offer the high energy density required for long-distance heavy transport where conventional battery weight remains a significant engineering hurdle.