The article discusses the importance of reducing carbon emissions in the transportation sector, particularly in urban bus transportation. It compares different powertrain types for 18-meter city buses, including gasoline, diesel, hydrogen, and electricity. While fully electric vehicles are currently the most favorable choice in terms of emissions reduction and cost efficiency, the study proposes a positive scenario for 2030 where hydrogen fuel emerges as a promising candidate. Hydrogen-fueled vehicles are highlighted as having the potential for low emissions and cost-effectiveness with the increasing production of green hydrogen. The adoption of hydrogen in the industry, particularly through H2ICE, is seen as a step towards reducing carbon emissions and achieving cost-effectiveness. If the forecasted hydrogen production and distribution scenarios are embraced, a more environmentally sustainable operation can be achieved by 2030. The article emphasizes the need for clean, renewable energy sources in transportation to address global warming and GHG emissions, showcasing the importance of advancements in powertrain technology for urban buses.