The future use case for hydrogen fuel

[phart010 | 1,708]

I’ve been listening Elon Musk talk about the whole idea behind Tesla. He says his main goal was never to make a profitable company. Instead, the idea behind Tesla was to pave the way for the electric car industry in order to accelerate mass adoption by industry players by as many as 10 years earlier than it would have been adopted in an organic market (by the way I think he said this like 10 years ago). 
 

So there are those that say that Tesla will not continue to grow at the same rate because it has a lot of competition coming to the EV market. If that proves to be true, it would only strengthen Elon Musks claim that he never intended to be profitable, his bigger goal was just to persuade the rest of the car industry to make full EV cars on a massive scale.

His other big goal is to send people to Mars and have a Mars colony by 2050. One of the big hurdles he explains is that Mars is a one way trip due to the amount of fuel that needs to be burned to get there. So immediately from day 1 of landing the first thing that needs to be worked on is a refinery to be able to refuel rockets. A main problem is that we don’t know for certain about the presence of fossil fuels on Mars.

What we do know about is how to make Hydrogen fuel. And the ingredients to hydrogen fuel are on Mars. I wonder why SpaceX is launching rockets with fossil fuel derived rocket fuel. Shouldn’t they be looking into developing hydrogen based rocket fuel? I believe NASA has already come up with a hydrogen based rocket fuel but they don’t really use it because the technology isn’t optimized.

If Elon Musks number one concern is not profitability, he should develop a Hydrogen fueled Tesla. Then they get all kinds of big data from drivers to enhance their understanding and develop the technology. It’s always commercialization of technology that improves the technology over time. If they commercialized hydrogen, then we’d probably learn enough about it to be able to develop good hydrogen fueled rockets and then we’d have a fuel source to have return trips from Mars

Edited March 3, 2021 by phart010

[RH | 4,924]

Zero research into this statement but I have no clue but this is what I recall being the problems with hydrogen.

For rockets, I think the main issue is Oxygen.  Oxygen is free for rockets in typical atmosphere, but once you start getting into the thinner regions, you also have to have O2 tanks with it to be able to burn the Hydrogen.  That becomes a weight issue.  Accelerants that contain Oxygen are likely lighter, but again, I could be wrong.  I think I've heard that, though and that's the main issue.

Regarding cars, I think there were two main reasons why Hydrogen cars have never made their way into the mainstream.  Getting pure Hydrogen and reliably isn't easy.  I think getting pure H2 requires a chemical process where you mix solution A with solution B and a byproduct is pure H2 gas.  Great, but it creates a lot of waste.

The second issue is that Hydrogen is extremely explosive.  I mean, I get it.  A car engine is a controlled, explosion reactor but I think a hydrogen leak + spark is far more dangerous than a lighting a match near an open gas tank.  Plus, you can smell gas and assume there's a problem, but not H2.  This means they would likely add an additive (just as they do to natural gas) so you can smell it and know somethings wrong if there's a leak.  Regardless, one small spark near a hydrogen leak, and the whole thing would likely explode.  This doesn't happen with gasoline because gasoline in it's liquid form is not very flammable.  What is super-flammable is the fumes of gas, and since it's highly volatile, it's easy to get a good ignition source from it.

 

[phart010 | 1,708]

21 minutes ago, RH said:

Zero research into this statement but I have no clue but this is what I recall being the problems with hydrogen.

For rockets, I think the main issue is Oxygen.  Oxygen is free for rockets in typical atmosphere, but once you start getting into the thinner regions, you also have to have O2 tanks with it to be able to burn the Hydrogen.  That becomes a weight issue.  Accelerants that contain Oxygen are likely lighter, but again, I could be wrong.  I think I've heard that, though and that's the main issue.

Regarding cars, I think there were two main reasons why Hydrogen cars have never made their way into the mainstream.  Getting pure Hydrogen and reliably isn't easy.  I think getting pure H2 requires a chemical process where you mix solution A with solution B and a byproduct is pure H2 gas.  Great, but it creates a lot of waste.

The second issue is that Hydrogen is extremely explosive.  I mean, I get it.  A car engine is a controlled, explosion reactor but I think a hydrogen leak + spark is far more dangerous than a lighting a match near an open gas tank.  Plus, you can smell gas and assume there's a problem, but not H2.  This means they would likely add an additive (just as they do to natural gas) so you can smell it and know somethings wrong if there's a leak.  Regardless, one small spark near a hydrogen leak, and the whole thing would likely explode.  This doesn't happen with gasoline because gasoline in it's liquid form is not very flammable.  What is super-flammable is the fumes of gas, and since it's highly volatile, it's easy to get a good ignition source from it.

 

All respect to you for the insights. One thing I want to add is that there was similarly a whole list of reasons that electric cars would not be practical 15 years ago, but the tech has now improved and it’s looking pretty practical for mass use today. And there are actually lithium chemistries that have significantly more power density than the ones currently being used, but they are not being used because they are also much more volatile. But there’s already proven work to essentially eliminate the risk of fire on these as well, it’s just a timely process to get through the commercialization due to patent holders wanting to get their recognition and so on. 
 

I think there’s going to be a solution to each problem; if there’s a will there’s a way.

[LeatherRebel5150 | 1,056]

We tried hydrogen flight once

 

[LeatherRebel5150 | 1,056]

But in seriously, Im sure using hydrogen fuel is the only way to do it on another planet as theres no guarantee of anything else. But we know you cam extract if from minerals as well as oxygen. Also isnt rocket fuel primarily oxygen and hydrogen anyway? or am I misremembering 

[phart010 | 1,708]

3 hours ago, LeatherRebel5150 said:

But in seriously, Im sure using hydrogen fuel is the only way to do it on another planet as theres no guarantee of anything else. But we know you cam extract if from minerals as well as oxygen. Also isnt rocket fuel primarily oxygen and hydrogen anyway? or am I misremembering 

I’m no rocket scientist, but I thought that rocket fuel was kind of similar to jet fuel. Jet fuel is a hydrocarbon, it’s refined from crude oil

Edited March 3, 2021 by phart010

[darkchylde28 | 1,546]

On 3/3/2021 at 4:45 PM, phart010 said:

I’m no rocket scientist, but I thought that rocket fuel was kind of similar to jet fuel. Jet fuel is a hydrocarbon, it’s refined from crude oil

It can be a mix, although the most common rocket fuels consist of things like liquid oxygen, liquid hydrogen, hydrogen peroxide, etc.  There's some limited use of things like highly refined kerosene and liquid methane, but those have only been used in stages which have specifically been designed to operate only at Earth-specific atmospheric pressurization.  Engines that are designed to go out somewhere and come back would have to rely on the non-hydrocarbon fuels since those don't require an atmosphere like ours to create the required amount of thrust for the rocket to lift off and/or reach escape velocity.

https://en.wikipedia.org/wiki/Rocket_propellant