Hydrogen has the potential to dominate the market for zero-emissions trucking in the US, but there is no chance of it making even minor gains into the passenger vehicles sector, the federal government has indicated.
In a US National Blueprint for Transportation Decarbonisation, released yesterday (Tuesday), four departments of the US government — the Departments of Energy, Housing and Urban Development, Transport, and the Environmental Protection Agency — laid out a roadmap for decarbonising the entire US transportation sector by 2050, encompassing cars and vans, heavy goods vehicles, rail, aviation and shipping.
According to the blueprint’s technology opportunity matrix (see below), hydrogen has the greatest long-term potential of all fuels in the long-haul segment, outstripping both battery-electric vehicles (BEVs) and sustainable liquid fuels.
The blueprint, which will be used to inform transportation policymaking and long-term planning, champions a systems approach to decarbonisation, in which the entire transport supply chain is considered at once, from power grids, urban planning and refuelling to vehicle manufacture and fleet management.
It outlines three strategies: convenience, which is essentially smarter urban planning that minimises the need for transport use; efficiency, to minimise emissions and encourage use of public transport; and the transition to clean options such as zero-emissions vehicles.
But transitioning to zero emissions vehicles will yield by far the most emissions reductions, it said, with the first two strategies serving to “ease the challenges” of the third.
Hydrogen vehicles are “appealing” for future long-haul operations requiring greater vehicle range and faster refuelling times than batteries, the departments said, highlighting the research into both H2 fuel-cell electric trucks and the use of hydrogen in internal combustion engines (ICE).
And hydrogen also has potential in the rail and maritime sector, when the use of hydrogen to make ammonia and methanol for shipping are factored in.
But the cornerstone of US government’s transport decarbonisation strategy hinges on the uptake of battery-electric vehicles (BEVs), which Washington expects to dominate the market for zero-emission light-duty (passenger) vehicles — which currently accounts for 49% of all US transport sectors emissions — by 2050, and much of the medium-duty market as well.
This is fuelled by BEVs’ advanced penetration into the market, the ready availability of vehicles and refuelling infrastructure, as well as an astounding 90% reduction in battery costs over the decade to 2020.
By comparison, the use of hydrogen in passenger vehicles will be negligible, the matrix suggests.
Even medium-haul road freight is likely to see a high penetration of BEVs, the government added.
The blueprint gives no explicit explanation as to why H2 will lose out in these segments, but several reports have found that hydrogen will be too expensive to use as a fuel in all but the most niche road freight applications, such as heavy duty, long-range trucking where the vehicle needs to be refuelled fast.
The impact on the electricity grid will also be a factor in future systems planning, according to the blueprint, which noted that hydrogen and e-fuels (synthetic fuels made from electrolytic hydrogen and captured CO2) will require two and four times as much electricity per mile travelled, respectively, than BEVs, which are expected to become the largest source of load growth in the US.
“Widespread transition away from fossil fuels for transportation will have far-reaching consequences for energy and electricity systems, including new opportunities for significant electricity load growth, while also requiring greater co-ordination for planning and operation between the transportation and electricity sectors,” it added.
Hydrogen remains a contender in maritime, via the use of H2 derivatives ammonia and methanol, and rail, the government noted, but warned that more research is needed to determine their life-cycle emissions and pollution potential. And hydrogen could yet fuel sustainable aviation, but technological progress on the fuel is unlikely to have any emissions impact until 2050, due to the long lifecycles of commercial aircraft, it said.
Both battery-electric and e-fuels could have a role to play in aviation alongside hydrogen, it added, but the use of sustainable aviation fuels (some of which are made from hydrogen) will yield the most emissions reductions until mid-century.
“The Department of Energy is prepared to implement this blueprint alongside our partners within the Biden-Harris Administration to ensure all Americans feel the benefits of the clean transportation transition: good-paying manufacturing jobs, better air quality, and lower transportation costs,” said Jennifer Granholm, US secretary of state for energy.