With the current state of automotive electrification, very large
uncertainties preclude predicting which electrification pathway is likely to
be most economical over a 10- to 30-year outlook. Therefore, the development
of a range of technologies should continue including statically charged
battery electric vehicles (BEVs), fuel cell electric vehicles (FCEVs),
plug-in hybrid electric vehicles (PHEVs), and electric vehicles designed for
a combination of plug-in and electric road system (ERS) supply. The most
significant uncertainties are for the costs related to hydrogen supply,
electrical supply, and battery life. Consequently, efforts should focus on
the techno-economic analysis of these parameters.
The cost of green hydrogen will depend on many factors, including
electrolyzer and fuel cell costs, life spans and efficiencies, distribution
and storage costs, the time-based cost of renewable electricity, and the
extent to which more efficient electrolyzers with heat recovery methods can
be used. Green hydrogen will be required as an industrial feedstock for
difficult-to-decarbonize areas such as aviation and steel production and for
seasonal energy buffering in the grid. The leveling effect of this flexible
demand must be considered with respect to time-dependent electricity costs.
Greater certainty around hydrogen leakage rates—as well as the impact of
producing composite tanks and fuel cells—is required to determine the carbon
intensity of a hydrogen energy system.
Variation in estimates for the electrical distribution costs linked with
different pathways is largely the result of differences between geographical
regions. Unit costs are well established for power converters and cabling
associated with transmission and distribution. What is required here is a
greater number of region-specific cost models, especially for ERSs.
An improved understanding of vehicle battery life is vital in evaluating the
cost of battery and hybrid vehicles. For ERSs, it is critical to understand
how battery life will be affected by frequent cycling and the extent to
which battery technology from hybrid vehicles can be applied. ERSs must also
now be tested on busy public roads to establish maintenance costs.