Recently, I assessed the transportation potential for hydrogen outside of automotive uses given the obvious success of battery-electric vehicles at smaller scales. In that assessment, I concluded that there was an opportunity for niche use of hydrogen in long-haul trucking, freight trains, passenger jets, and freight shipping. This does leave potential for the Nikola hydrogen fuel cell truck pictured here or similar vehicles to compete in the future.
But what percentage of total transportation energy needs might be fulfilled by hydrogen in those niches? In the last article, I pointed out that some of these niches are very big, so while hydrogen was off the table for smaller vehicles, that didn’t mean that it was inconsequential.
Increasing the consequence is that these modes of transportation are much more polluting than cars and light trucks, and are typically less efficient in their use of fuel, increasing greenhouse gas emissions as well.
This chart from the US Energy Information Administration is informative. Not all countries will have this same mix, but it’s representative of the categories and is not inaccurate as a basis for broader comparison.
Also in my kit bag is my personal model of potential electrification of automobiles over the coming decades. It suggests that we might see battery electric vehicles start to reduce petroleum use to 2014 levels by 2040 or 2050 in the two scenarios I modeled. This is useful, as it indicates that the majority of forms of transportation will still be using fossil fuels for the next couple of decades. Finally, I recently published an assessment of what factors would play a part in any sophisticated model of oil use (and noted that my model did not include all of these factors).
As the breakdown of energy sources for transportation shows, 91% of US transportation energy comes from oil, with the remainder coming from natural gas and biofuels, mostly ethanol blended with gasoline. The majority of the modes of transportation will shift to battery electric, or in the case of trains, to a combination of battery and trolley-line electric in the 50 year time frame. Fossil fuels will still play a large part in the military, in ocean-going freighters, and in freight trains in many parts of the world. Biofuels, especially biomethane used with hybrid electric systems, will likely take a greater portion of the load. It’s likely that long-haul passenger jets will still be consuming fossil fuels in the 50 year timeframe as well.
What room does this leave for hydrogen?
Based on my read of the potential, we might see the EIA numbers shift in the following ways over the 10, 20, and 50 year timeframes. This is a guesstimate without modeling underneath it, but my guesstimate is based on significant pre-thinking, review of other models, and my own modeling of one use of oil.
I’d projected closer to 5% penetration when I first built this prediction. Based upon the past 20 years of experience with battery electric vs hydrogen vehicles, I suspected that hydrogen would not be as competitive in 50 years as it might seem today for the applications where it still has potential today. As a result, I downgraded the 50 year projection somewhat. Similarly, my original thinking had a higher penetration in the 20 year timeframe, but sober second thought made me realize that given the lifespan of many of the vehicles in these categories, 20 years was too short for significant change. Close to 1% is possibly still too high for two decades of transformation
And I am reasonably sure that the use of hydrogen is unlikely to increase after that period. The cycle of creation, distribution, and use is too inefficient, and it’s unlikely to become significantly more efficient, while putting electricity directly into batteries and using it from them is already much higher efficiency than the theoretical limits of hydrogen and the ratio of battery capacity to cost is improving radically.
This is total use of hydrogen for transportation needs, and that includes hydrogen produced by steam reformation of natural gas, not just hydrogen produced from renewable resources. I expect in 50 years a substantial portion of hydrogen will still be coming from natural gas simply because it will remain the least expensive way to extract hydrogen. Further, emerging prices on carbon will mean that the CO2 emitted is more likely to be captured and used or sequestered. As a result, while this will reduce pollution and CO2 emissions somewhat in these categories, it will still be a higher carbon load than battery electric transportation modes charged from what will be a very low-carbon grid in most parts of the world.
This may seem to downplay the significance of this, but the USA alone uses roughly 220 billion gallons of hydrocarbon fuel a year for transportation. 3.4% of that is still 7.5 billion gallons, and the gallons which will be diverted are the most polluting and have the highest greenhouse gas emissions.