Based on their calculations, the overall efficiency of biomass “from sun to wheel” is between 0.01% and 0.05%. By contrast, charging electric vehicles using solar power can produce efficiencies of 3% to 20% on the same metric. Electric drivetrains are also “5 to 10 times more efficient than internal combustion engines.” Even if power from conventional fuels is charging the vehicles, overall emissions are likely to be lower. It is also much easier to sequester greenhouse gas emissions from big power plants than to do the same thing with car exhaust.
If you insist on maintaining a car-based society, basing it around electric vehicles charged using renewable energy or fossil fuel generation with sequestration seems to be the way to go. Hybrids are only a minor improvement and hydrogen fuel cells are a non-starter.