Low Tech vs Interstellar societies...

[atpollard]

Something ELSE has to generate the electricity that is needed for BOTH use cases.

Hydrogen is not created from electricity … it comes from chemical manipulation of OIL (just as most Elecltricity is generated from fossil fuels). So both start out as 100 watts of “coal/oil/natural gas”, but the Electric Car ignores the 66% energy loss generating electricity while the Hydrogen Car is charged for the 25% loss in generating the Hydrogen.

That is an deliberately dishonest comparison.

 

[McPerth]

Think about Atmosphere: A-C type worlds with Fluid Oceans that are not composed of H2O, but from other molecular substances.

Well, I guess much will depend on what are those fluid oceans made of. Hydrogen may be taken from other soruces than water, for what I know...

And, in any case, I guess in those not-friendly worlds most people live in domes, and personal transport is less needed than mass transport, where pure electrical means are less an issue, so I mostly think on friendly ones, where people roams free on the atmosphere with personal (utilitarian) means.

Hydrogen is NOT quick to refuel. It's also ridiculously expensive (in the real world).
Take your usual petroleum fuel price and multiply it by 6-10x (or more!) and that's the typical hydrogen refueling station price.

But, as you say yourlef above in the post, with ample and cheap power and better superdense materials for storage, this will no longer be the case.

Zaragoza, Spain you say?

Yes

You no longer need to make an overnight stay in Zaragoza at a (low power) destination charger before completing your road trip between Barcelona and Madrid. Simply plan for a 30 minutes (or less) charging session at the Supercharger station (get out of the vehicle, stretch your legs, use the water closet, get a drink, etc.) before resuming your journey. So ... 6-8 hours in an electric vehicle too.

Well, you can really have a good lunch in Zaragoza, as food is good there ...

Nonetheless, unless this has also improved, those quick charges burn the batteries quite faster than slow ones, and they are the most expensive part of your car...

Fuel Cells have their niche roles, including Air Independent Propulsion (AIP) in non-nuclear power submarines(!) while submerged ... but they aren't a panacea and they aren't "best in slot" for every single use case where you need power. However, those use cases tend to be in "challenging environments" (such as in space or submerged in the ocean) rather than in terrestrial vehicles (cars, busses, trains, etc.).

Well, I see it the opposite way: once those problems are solved, fuel cells are the default for small power plants (car, motorcycle, small to medium planes, etc.) in friendly planets, while batteries are the alternative when they may have problems (including non-friendly plantets, though they will use colosed environments and so less such personal transport). Both have issues, but I see easier to solve and probably cheaper...

By the way, may I ask you a favor? Try to avoid using so many acronyms, as they make reading it slower for those of us not used to them (not to tell if English is not your native language, as it's my case).

 

[Spinward Flow]

Hydrogen is not created from electricity … it comes from chemical manipulation of OIL (just as most Elecltricity is generated from fossil fuels). So both start out as 100 watts of “coal/oil/natural gas”, but the Electric Car ignores the 66% energy loss generating electricity while the Hydrogen Car is charged for the 25% loss in generating the Hydrogen.

That is an deliberately dishonest comparison.

I see that there is a rather marked lack of education and knowledge on the subject of hydrogen engineering among our posters in this thread, to a degree that is rather worrisome.

Therefore, I'm assigning some "homework" to anyone who wants to be Better Informed™ about the topic.

But, as you say yourlef above in the post, with ample and cheap power and better superdense materials for storage, this will no longer be the case.

With "enough high tech" you can solve almost any problem.
The trouble is that right now (in the real world) the necessary technology/engineering prowess to "master" the hydrogen fuel challenge has not been reliably accomplished. As evidence, I offer recent NASA issues with hydrogen leaks causing delays in multiple launches (not just the current one for Artemis 2 that got delayed). Hydrogen, especially liquid hydrogen, really doesn't want to stay confined inside of containers.



Be kind of hilarious if the most reliable method to "contain" hydrogen wasn't a (made of matter) pressure vessel that atomic hydrogen LOVES to permeate through ... but instead what you need is a "gravitic bottle" that uses (artificial) gravitic fields to confine hydrogen (much more safely) within a container/tankage volume at an acceptable level of long term reliability.

Well, you can really have a good lunch in Zaragoza, as food is good there ...

It's Spain.
By definition, the food is going to be better there than almost anywhere that is an English speaking country.

 

[Spinward Flow]

Nonetheless, unless this has also improved, those quick charges burn the batteries quite faster than slow ones, and they are the most expensive part of your car...

As I said before, your information/knowledge on this subject is out of date.

With modern (last 5 years?) battery management systems, quick charging no longer imposes a "penalty" on battery life ... which is basically what you're asserting.

OLDER battery pack systems, especially those which lacked a battery management system (heating, cooling, power load balancing, the whole thing) or are unable to update their battery management system (for conversational purposes, that means every vehicle company except Tesla) were either not designed to handle fast charging or otherwise were unable to accept power at fast charging speeds.

Current "new" vehicles are being built with battery management systems already integrated which permit incredibly fast charging speeds. In fact, the Chinese battery manufacturers and car companies are racing ahead to develop and field faster and faster charging speeds without worrying about the economic tradeoffs involved in that race. As evidence for this assertion, I'll cite these references which were posted in the past week:

And as for the question of "how soon will autonomous driving become a reality?" ... well ... the answer is ... SOON™ ...

 

[McPerth]

The trouble is that right now (in the real world)

I trust you knowledge in current real world, but here we're also talking about Travller universe, and that's what I mean when I talk about superdense materials and cheap power to produce Hydrogen...

As I said before, your information/knowledge on this subject is out of date.

I already warned you this might be the case...

With modern (last 5 years?) battery management systems, quick charging no longer imposes a "penalty" on battery life ... which is basically what you're asserting.

And yet, I'm warned by people who (unlike me) claims to know about the issue not to recharge batteries too often if I want them to last...

And as for the question of "how soon will autonomous driving become a reality?" ... well ... the answer is ... SOON™ ...

From the engineering point of view, maybe, from the legal one, I'm not so sure...

 

[Enoki]

An alternative to hydrogen for portable fuel is ammonia, specifically anhydrous ammonia. In terms of Traveller, you can get this almost directly from many gas giants as it's already present in the atmosphere. That means it takes little energy other than to collect and filter it to make it into a fuel.

 

[King Midas]

If you look at that gray tractor, "none" of those parts can be made locally. They all need specialty manufacturing. No one is going to pound any of those parts out at a blacksmith.

Nobody builds carburetors in their garage (not those types of garages). Can someone mate a foreign carburetor salvaged from another machine? Oh, for sure (with obvious caveats). That's a different problem. But making one out of raw materials, not so much. That requires specialty manufacturing not just for the carb body, but for the small parts, the jets, the springs. About the only thing that might be more locally available is the gaskets if you can find some suitable gasket material (but those also require specialty manufacturing -- tree bark likely won't work).

You might be able to make one with foundry that can cast the body, then machine out the holes and such, but even that it likely above a typical machinist.

Then, of course, there's the tubing...

Showing my age here. I saw this when it was first broadcast. We all know gaskets are easily available from common kitchen supplies: