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Comment by sdkjfwiluf | Hacker News Reader

Hydrogen and hydrocarbon fuels are just sources of electrons. The beauty of a real electric car is the efficiency of going directly from stored electrons to power.

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Refueling time and storage equipment seems like major differences between hydrogen and battery. They both have slightly different use-cases that make different bets on future technology. Maybe one will win out or maybe both will play a role. I'm personally waiting for the Nucleon to come back.

Refueling time (...) seems like major differences between hydrogen and battery.

Unless you do battery swapping, in which case they don't seem all that different: https://www.youtube.com/watch?v=H5V0vL3nnHY

and transportation. Hydrogen is a very inefficient way to transport electrons compared to wires.

I'm not an expert at any of this stuff and this math could very easily be wrong, but I just spent some time with Wolfram Alpha validating that claim. a 40,000 liter hydrogen truck can carry 425 gigajoules of liquid hydrogen; if it drives 500 miles, a diesel tractor trailer getting 5mpg would burn 100 gallons of diesel, that's 14 gigajoules of energy (now keep in mind that much hydrogen only weighs 3000kg - a typical load for a tractor trailer is 10000-20000kg) - if it was a fuel cell truck, it could be twice as efficient as an ICE so would only need 7 gigajoules. 7 gigajoules is 1.6% of the transported 425 gigajoules of energy. A state of the art HVDC transmission line loses 3.5% per 1000 km, so it seems like a hydrogen truck might actually be more efficient than wires.

what about locally-produced electricity ? If an electric car recharges on locally-produced electricity along its journey then we can eliminate transmission losses

There are hundreds of what-ifs that influence which will be a better choice, IMO it's not clear cut that one technology is better enough for all situations that it'll crowd the other one out of the marketplace entirely.

firstly, upvote for doing the calculations!

I wonder what happens when you factor-in maintenance, safety and production costs

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