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RE:Fuel Cell vs. hydrogen in ICE

[iiioiii]

@SORNG1, here is an excellent series of videos that describe the merits and drawbacks of using hydrogen as a fuel in an ICE (Internal Combustion Engine) in comparison to a fuel cell:

Why Hydrogen Engines Are A Bad Idea:
https://youtu.be/1Ajq46qHp0c

The DIfference Between Gasoline and Hydrogen Engines:
https://youtu.be/l6ECwRnJ0Sg

How Hydrogen Fuel Cells Work:
https://youtu.be/0jnZFGx_4kY

There are good reasons why a fuel cell is superior to an ICE run on either gasoline or hydrogen. If hydrogen is used alone by an engine optimized for the gas, it's a more inefficient method compared to a fuel cell as you'll see. This is a poor way to burn a still expensive fuel especially if you're building an engine specifically for this purpose.

There's occasionally been discussion, primarily amoung amateur enthusiasts, of even mixing gasoline with hydrogen. While the videos don't go into combining some sort of gas/hydrogen hybrid engine, you'll see that this would still be a more inefficient approach given the losses incurred primarily due to the waste heat produced by an ICE. Further, the refit would be overly complex for any exisiting engine, not only because mixing the hydrogen with the vaporized gas within the cylinder would and does require some serious finess in an already cramped engine bay, but also due to the different physical properties of the two fuels and the subsequent changes in the engine required to optimize efficiency.

When discussing which is cheaper, I think the problem here is an issue of considering both the life-cycle of the options and the benefit of economy of scale. For the sake of argument we'll say the hydrogen ICE is cheaper to produce than the fuel cell. Remember from the videos that the final efficiency of fuel cell is approximately twice that of the hydrogen ICE; therefore twice as much fuel will be used for the same distance. So, since the difference in up-front cost is fixed, the more inexpensive choice is then dependant on the relative life of the two options. I didn't take a look at some actual specifics but I'd hazard a guess that they are comparable to eachother, which I'm also assuming is long-lived, and so fuel costs will have an important effect on which option is ultimately cheaper with an advantage to the fuel cell.

Further, as fuel cell technology is adopted more fuel cells are made and the economy of scale results in cheaper fuel cell production costs. This reduces the up-front cost and narrows whatever initial advantage the hydrogen ICE had compared to the fuel cell. I'd expect that since hydrogen engines are rather uncommon (thus suffering the same production inefficiencies of fuel cells - if not more) and that fuel cells are more fuel efficient, the fuel cell therefore will ultimately be the more cost effective option.