For the hydrogen-powered fuel cell electric vehicle scenario, we assume that FCEVs are added later in time than the PHEVs, displacing ICVs, HEVs, and PHEVs in proportion to their number sold in the PHEV scenarios.  Note that this model assumes a very gradual introduction of FCEVs, with much slower market penetration than for HEVs or PHEVs. FCEV sales do not exceed 50% until mid-century, and do not reach 50% of cars on the road until 12 to 15 years after that as older cars retire.

The two secondary scenarios, the battery EV scenario and the hydrogen ICE HEV scenario use this same market penetration rate, with the BEV or H2 ICE HEV replacing the FCEV sales.  In other words, this model does not consider both BEVs and FCEVs, but treats them separately to clearly demonstrate their differences. In reality BEVs and FCEVs will share vehicle sales, with BEVs serving as smaller city cars with limited range, and FCEVs serving as full-function, long range passenger vehicles and trucks and buses, as suggested by three major auto companies: GM, Toyota and Daimler.

The total number of FCEVs on the road in this model is compared with the FCEVs assumed in the 2008 NRC report, and also compared with the goal for FCEVs set by the public/private partnership in Germany which they call “H2 Mobility,” scaled to the US market. for example, the “H2 mobility goal is to deploy 600,000 FCEVs by 2020 in Germany. But the total vehicle light duty fleet in Germany is 41.1 million vehicles, compared to 135.2 million in the US in 2007 (latest data available). Scaling the German committment of 600,000 FCEVs to the US yields: 600,000 x 135.2/41.1 = 1.973 million US FCEVs. these number of FCEVs would correspond to 1.5% of the total 2007 vehicle fleet in both countries. 

This model is more conservative (slower build-up of FCEVs) than both the NRC model and also the German “H2 Mobility” commitments of German auto companies and hydrogen fueling suppliers

[HEV Scenario] [Gasoline PHEV Scenario] [Biofuel PHEV Scenario]