A recent study by the National Renewable Energy Laboratory (NREL) indicates a promising future for zero-emission medium- and heavy-duty vehicles (MHDVs) like battery electric and hydrogen fuel cell electric vehicles. By 2035 or even earlier, these vehicles could become cost-competitive with their diesel counterparts, fostering a greener transportation sector. NREL's analysis envisions a transition to Zero-Emission Vehicles (ZEVs) by 2035, potentially reducing emissions by 65% by 2050. Incentives provided by policies like the 2022 Inflation Reduction Act (IRA) play a crucial role in accelerating this transition and driving down emissions by up to 70%. The study, detailed in a recent iScience journal article, underscores the importance of advancements in technology and supportive policies in achieving total cost parity and emissions reduction goals. NREL's TEMPO Model was instrumental in assessing the evolution of MHDV driving costs and emissions across different scenarios, emphasizing the potential of ZEV technologies in transforming the MHDV sector.