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by throwaway5752 2983 days ago
You're unlikely to find a bigger proponent of clean and renewable energy than me, but there's a long time before that is going to hit industrial end use where there are certain constraints.

The energy density of li-ion is .05ish mj/l, vs 50ish for diesel. EVs are about twice as efficient at converting that energy than gasoline ICEs but that's still a large gap (and diesel is much more efficient, but I don't have that ratio handy) where weight and volume are constraints. Also, refueling time is hard to get down economically (you can trade out a full set of battery cells for new/charged ones, but more vehicle weight/complexity and infra to accommodate that).

A more efficient diesel is more meaningful to vehicle trends in Europe than the US, but I think regardless of type of hydrocarbon fuel sources, commuter use cases are closer aligned with EVs and you're right there that this development won't stop the trend there (and non-commercial vehicle usage is an enormous, perhaps largest, source of CO2 pollution).
1 comments
Retric 2983 days ago
IC engines with transmissions take up vastly more space and weigh quite a bit more than electric ones do which limits the impact of energy density.

Electric has ~4,200 lb to work with before weigh for components before you consider the weight of fuel. https://www.energy.gov/eere/vehicles/fact-620-april-26-2010-...

Mack trucks get ~6.5 mpg, so a 350 mile range would take ~5 Tesla battery's ~6,000 lbs. That's a little low, but far from useless just add how battery swaps and it's completely viable.

Long term, the move to in road charging means electric trucks will actually save significant weight over IC engines while also having unlimited ranges. http://money.cnn.com/2015/08/18/technology/uk-electric-cars-...

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throwaway5752 2983 days ago
That magnetic induction charging embedded in lanes in roads is really interesting and I didn't know about it. Thank you!

To be fair, 350 is low. Don't semis vary around 150 gallons of fuel capacity? There will also be a balance to update roads vs choosing rail in a multimodal logistic chain. Maybe the smaller EV range would be appropriate there for last mile. Anyway, I know it's complicated but I sure hope we solve this urgently.

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bmcusick 2983 days ago
Tesla initially had a battery-swap feature at its earliest Supercharger stations, but no one used it. For consumers, the recharge time was good enough even then.

Long haul trucks will probably use it.

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