With continued improvements in vehicle and fuel technologies (in line with U.S. Department of Energy
targets and vetted with industry), zero-emission vehicles (ZEVs) can reach total-cost-of-driving
parity with conventional diesel vehicles by 2035 for all medium- and heavy-duty (MD/HD) vehicle
classes (without incentives).
• Assuming economics drive adoption, ZEV sales could reach 42% of all MD/HD trucks by 2030,
reflecting lower combined vehicle purchase and operating costs (using real-world payback periods).
• In this scenario, ZEV sales reach >99% by 2045, and 80% of the MD/HD stock transitions to
ZEVs by 2050, reducing CO2 emissions by 69% from 2019.