Heavy duty decarbonization

Start by presuming electrification and forcing yourself to justify any departure, for two compounding reasons. Clean electricity is cheap as an energy input, and Lubershane expects it to stay cost-effective against biofuels, clean hydrogen and electrofuels even as power prices rise over the coming decades. On top of that, a battery electric drivetrain reaches something like 80% efficiency from electricity into the vehicle to motion, better than any alternative including hydrogen fuel cells. Two things then constrain it. The obvious one is energy density: a lithium-ion battery holds a couple of megajoules per liter where gasoline and diesel hold around 35, and the gap by weight is worse still, with fossil fuels at 45 to 50 megajoules per kilogram. The interesting move is what Lubershane does with the expectation of progress. He thinks it reasonably safe to assume at least a 50% density improvement for high-performance lithium-ion within five to ten years, that doubling is not crazy and tripling is theoretically possible over a longer arc, with the caveat that gains now appear to cost either money or charging speed. And then the point: even a two- to threefold improvement leaves batteries at an enormous disadvantage. Improvement does not rescue the hardest cases, so the density argument holds because of optimism about batteries rather than in spite of it.

The second constraint gets less attention and in some places binds harder, which is the power needed to charge things. Lubershane’s example inverts the intuition the density discussion builds. Drayage trucks at a port are close to the ideal electrification candidate, with short repetitive trips, heavy stop-and-go duty that batteries handle well and no meaningful range problem, and the Port of Long Beach has roughly 1,600 of them. Charge those slowly overnight at 100 kilowatts each and you have still created about 1.6 gigawatts of new peak demand concentrated around the port, which the port’s own study translates into adding 90 megawatts to every existing substation in the area if you had to stay within the current footprint. That is multiple transmission lines’ worth of power into one of the densest operational environments there is. The precedent he cites fixes the timescale: a project begun in 2011 to electrify cargo handling equipment and provide shore power to docked ships took a decade and required Southern California Edison to build a new 66-kilovolt line and four new substations. So a vehicle can be technically and economically viable while the place it refuels is not, and no better battery fixes that.

Mapping both constraints onto modes gives the ranking. Aviation is where density binds hardest, since flight has always been a fight against weight and volume, and Lubershane effectively rules out electrification almost entirely, allowing only very small short-hop aircraft that he calls meaningless for total aviation emissions. Shipping he calls less of an outright no-go, and there the binding measure is volumetric rather than gravimetric, because space consumed by batteries is cargo you do not get paid to carry. Ground transport is the opposite case: he sees a plausible path to high, though not necessarily complete, electrification of even Class 8 trucks over the coming decades, with heavy off-road and mining equipment a possible exception. His preferred bridge there is partial electrification, including battery swapping, which he argues solves three problems at once. A smaller battery costs less range and payload; swapping refuels nearly as fast as diesel rather than the 15 to 30 minutes fast charging optimistically needs; and the removed battery can charge slowly instead of demanding the roughly 8 megawatts that filling a 2-megawatt-hour truck battery in 15 minutes would take. He is candid that he is a sucker for the idea, and Kann supplies the objection he does not answer.

For what electrification cannot reach, biofuels come before hydrogen, because they are already in use at scale and their ceiling is visible. About 40% of the US corn crop already goes to ethanol and roughly 30% of soy to biodiesel, which Lubershane reads as close to tapped out, and the lifecycle benefit of those first-generation fuels is only 25% to 40% against fossil fuel, which he thinks fairly raises whether the food-crop tradeoff is worth it. Second-generation cellulosic feedstocks are more abundant with better carbon intensity, and he argues that is where the transport market should go first, while conceding that maxing out that resource globally and directing all of it to aviation would still solve only about half of aviation’s problem given expected demand growth. Hydrogen and its derivatives are therefore step three. Hydrogen beats fossil fuels by weight and loses badly by volume, only about two to three times better than a battery, so it still forces vehicle redesign, which is why he expects the answer to be upgrading hydrogen into denser molecules by adding carbon, ultimately captured from the air. That is the most expensive route available, since you pay for clean hydrogen, for carbon capture and for the synthesis. His conclusion is that paying it can still be correct, and here the episode turns on itself. If the real constraint is replacing long-lived vehicles and rebuilding hubs that cannot stop operating, then a drop-in synthetic fuel that requires changing neither is worth a large premium. Kann frames the hub as cutting both ways: concentrated enough that fixing it fixes most of the market, and far harder to change than adding chargers house by house.