Technology

a couple of notes: those cargo ships (the ones built after @1995ish) almost all use bunker oil or fuel oil to drive electric turbines, generating more torque and smoother power bands than traditionally driven props directly off diesel engines. it's still burning the worst of the worst in vast quantities, so it's a marginal upgrade at best, and one that only counts for the newer 30 years of production.

re: semi trucks - apparently there are some drivers who LOVE them and won't consider returning to ICE, but I imagine they're edge cases still. https://axleaddict.com/news/truck-driver-loves-teslas-semi-trucks

Most if not all freight locomotives are diesel electric as well.

You’re just not going to beat the energy density of diesel. 1 gallon of diesel fuel has roughly 40kwh worth of energy in it. Modern diesel motors are around 35% efficient.

So you’re looking at ~14kwh of useable energy from 1 gallon of diesel, weighing 7 pounds. So 1kwh is around 0.5lbs.

1kwh of EV battery currently weighs ~13-14lbs based on the model 3s battery capacity and weight as well as the Hummer EV.

So on a train or truck with a 5,000gal tank (just using the AC600X locomotive as an example), you’re talking 35,000lbs of carried fuel and 70,000kWh of useable energy.

To carry the same energy, you would need 910,000-980,000lbs of batteries. Twice the weight of the locomotive itself. Even if we increase the density by a factor of 10, you still need almost 3x the weight of batteries as you do diesel.

And the time to charge a 70MWh battery would be insanely prohibitive. Like a few days each time. With a 1MW charger you’re looking at minimum 70 hours if you could run at peak power with no losses. Realistically more like 80 hours with how chargers slow down as the battery gets full and charging losses.

Natural gas could used to be a little bit cleaner, but CNG vehicles use 12-15% more fuel to get the same power than diesels so it would really be a wash on CO2 emissions. And you would have to replace every diesel engine out there along with all the infrastructure just for a less efficient power source. Natural gas is phenomenal for large scale power plants, not as much for ICE vehicles.

It’s the same issue with large ships. You just can’t beat the energy density of petroleum. And ships use the nastiest byproducts of oil refining already because they’re so cheap. Banning using bunker fuel would just cause them to switch to diesel for a little more rather than go full EV. Going back to sail boats is going to happen before EV boats lol.

Same with planes. Batteries are just too heavy for aircraft in any large capacity. Plus it’s not like we really want a bunch of giant flying lithium bombs overhead. Putting out an EV fire is already insanely difficult. Imagine trying to put out the fire from a battery 10x larger that crashed in the woods somewhere.

Diesel isn’t going anywhere any time soon. I would imagine we start producing more biodiesel before the really heavy machinery goes full electric. And as long as there is diesel in use, it’s gonna make its way to consumers in large pickups because diesel can’t just sit around forever and companies are gonna do whatever they can to keep production high to make money.

Part of the trouble with alternative energy sources is that ICE engines, and their liquid hydrocarbon fuels, are really very good at both energy density and power output. Trying to power a ship like that on just solar panels would be completely impractical, even if the entire ship had a solid roof of solar panels above it. It just wouldn't have enough power. For energy storage, batteries won't help much. Between their weight and their lower energy density compared to liquid fuels, it just wouldn't be possible to power the whole ship with Lithium ion Batteries. And that's even before concerns about seawater, corrosion, or thermal runaway are taken into account. Wind would not mean powering generators, so much as it would just be a return to effectively sailing ships, even if it's done with a more efficient airfoil type sail.

The long and short of it is, we're really a very long way from replacing the power source of things like cargo ships and aircraft. This is where things like alternative liquid fuels can be valuable. There have already been successful experiments in capturing atmospheric carbon and using sunlight (not solar electricity, heat from concentrated sunlight) to drive a reaction that transforms that captured carbon into a diesel-compatible fuel. It will always involve a net loss, as far as an energy source, but the resulting fuel can still work in systems that traditional renewables can't replace, while being as close to carbon neutral as possible.

It’ll become rarer, but will never go away. As long as diesel is being made, heavier duty trucks will have a diesel option.

Even if it becomes a solely biodiesel option. You’re just not going to beat the efficiency, energy density, and quick refueling of an internal combustion engine until you can have a battery 1/15 the mass for the same energy, and can charge the thing in under half an hour, and doesn’t cost more than the vehicle itself when it’s time to replace it.

ICE engines, and diesels in particular can run for millions of miles. The record for a semi mileage is just over 3 million miles on the engine. You’re not going to find a battery pack that can go anywhere remotely close to that long. Especially in a heavy use vehicle like a truck that will be constantly going through charge cycles.

Just looking at the Tesla semi, the 500 mile range battery is 900kWh. A 100kWh model S battery costs $15,000 to replace, with $13,500 of that being the battery itself. Scaled up, the semi battery would be in the $90-100k range to replace.

The average semi runs around 100,000 miles per year. If you can get 1,000 full charge cycles out of the battery, you’d be replacing one every 5 years to the tune of nearly $100k each time. Not to mention replacing the electric motors themselves at several grand pop, and those don’t tend to last as long as the battery. Especially in a truck hauling 82,000lbs.