Is it safe?

[Peter234]

Now, we are rushing into a new stage where hydrogen energy as practical energy is being used by millions of people. My question is whether it is dangerous or safe? I would like to know more about the use of hydrogen. I had only limited knowledge about it. What are the pros and cons of this hydrogen-fuelled vehicles hydrogen-fuelled vehicles compared to conventional vehicles?

 

[SZR48207]

I must be really out of the loop if millions of people are now using hydrogen energy vehicles. I thought those fell out of favor 10+ years ago.

 

[JunkdrawerDog]

Yeah...here's my hydrogen fueled car. I keep it in the garage next to my jet pack.

 

[c502cid]

Quite a few of them running around California. I was following one merging onto a freeway. They hit the go pedal and water came gushing out of the exhaust pipe, like someone turned on a hose, it was actually pretty cool to watch, no shortage of power either.

 

[billt460]

Hydrogen is not "practical" because it takes more energy to manufacture than it produces. Claiming hydrogen is "practical" energy, is a lot like claiming a Tesla is "green" when it uses electricity to recharge it's batteries, that is supplied by a coal fired power plant. The only hydrogen powered vehicle that is / was being produced in any numbers was the Toyota Mirai. And they were only available in a few small areas. Where they had an even smaller network of hydrogen refueling "stations". Not to mention if you drove them beyond their range cross country you were SOL, because you couldn't buy fuel to get you back. In that regard they were / are a lot like a Tesla without a recharging station.

Not only that, but the fuel was subsidized by Toyota for the first 2 years of ownership. (Basically "free" because they nailed you for it in the purchase price of the vehicle). After that the hydrogen cost a small fortune to buy if the owner paid 100% out of pocket. Which basically made the resale value of the car worth only slightly more than the metal it contained. These things are much like Tesla's. An expensive novelty for a guy who has to have the latest and greatest. (Or at least what they think is the greatest).

Hydrogen powered vehicles will never be practical, or for that matter economically viable. At least until they come up with some new way to produce hydrogen in abundance cheaply. And I wouldn't hold my breath on that.

 

[BMWTurboDzl]

EV's are comparatively green being that a majority of them are titled in states which do not rely on coal power for recharging.

 

[BMWTurboDzl]

The cheapest way to create hydrogen in sufficient volume is also the dirtiest.

The tanks must keep the fuel in a liquid state for as long as possible but the hydrogen will eventually turn into a gas and slowly get vented into the atmosphere in order to relieve pressure. The tank design used by BMW some 15 or more years ago would be empty in a little over a week.

Hydrogen just doesn't have sufficient energy density to make it viable.

 

[kschachn]

Originally Posted by Peter234
Now, we are rushing into a new stage where hydrogen energy as practical energy is being used by millions of people. My question is whether it is dangerous or safe? I would like to know more about the use of hydrogen. I had only limited knowledge about it. What are the pros and cons of this hydrogen-fuelled vehicles hydrogen-fuelled vehicles compared to conventional vehicles?

Did you just cut-and-paste most of that, and did you get one of your posts deleted?

There is probably no fuel that is less appropriate for a motor vehicle than hydrogen. The energy density is atrocious and providing it as a liquid is silly beyond belief. The thermodynamic penalty of liquefying hydrogen is only exceeded by helium, there is zero opportunity to have a net positive energy balance.

It would be hard to dream up a less appropriate fuel.

 

[Dave Sherman]

I would say the safety is on par with cars and trucks powered by LPG. Maybe even a little safer, since if it leaks hydrogen is lighter than air and rises up. As others have said, not terribly practical to generate it and store it. It might be attractive from the standpoint of having water as the emission and having an ample supply of water from which to create hydrogen, but for the energy needed you would probably be better off with an electric vehicle.

In my youth I though it would be a brilliant idea to have a car that electrolyzed water from a tank to make hydrogen and oxygen, burned it in the engine, then condensed the exhaust and returned it to the tank. Fuel your car with water! Then later on I learned about that pesky second law of thermodynamics...

 

[Kestas]

The last I read of this technology 30 years ago mentioned using a Titanium-based bed in the fuel tank, which would safely tie up the hydrogen, then somehow liberate it for use. I believe one drawback was the weight of the tank. I'm sure it didn't have much significant range.

 

[WyrTwister]

Originally Posted by Peter234
Now, we are rushing into a new stage where hydrogen energy as practical energy is being used by millions of people. My question is whether it is dangerous or safe? I would like to know more about the use of hydrogen. I had only limited knowledge about it. What are the pros and cons of this hydrogen-fuelled vehicles hydrogen-fuelled vehicles compared to conventional vehicles?


To the best of my knowledge , you can not drill a well and pump hydrogen from the ground . It must be manufactured . Which is expensive and requires energy .

So think of it as strictly a energy storage system . As is a battery . And you loose energy in each step of the process / conversion .

Much more practical to use butane or propane to fuel a vehicle .

Or gasoline or diesel . Hey , we already do that ! And no reason to have to change the infrastructure .

Go out and drill a hydrogen well , that is producing cost effectively . Then come back and talk to us . Otherwise , it is just another pie in the sky pipe dream .

 

[cdlamb]

Originally Posted by BMWTurboDzl
EV's are comparatively green being that a majority of them are titled in states which do not rely on coal power for recharging.

Do owners of Electric Vehicles pay a "Road Tax". In Canada a portion of fuel taxes are supposed to go towards maintaining roads. I would wager that once there are enough EV's on the road there will be a "tax" added on to a yearly registration, or onto your electricity bill.

 

[kschachn]

Originally Posted by WyrTwister
Otherwise , it is just another pie in the sky pipe dream .

A pipe in the sky is of course the best solution, but too bad you need a 93,000,000 mile pipe.

 

[BMWTurboDzl]

Originally Posted by cdlamb
Originally Posted by BMWTurboDzl
EV's are comparatively green being that a majority of them are titled in states which do not rely on coal power for recharging.

Do owners of Electric Vehicles pay a "Road Tax". In Canada a portion of fuel taxes are supposed to go towards maintaining roads. I would wager that once there are enough EV's on the road there will be a "tax" added on to a yearly registration, or onto your electricity bill.


A few US states have either implemented or are considering it. At the moment the EV taxes are insufficient to close the funding gap, however current levels of fuel taxes in general have been insufficient for decades. Fuel taxes are a political hot potato in the US because the States can levy their own individual tax on top of the Federal tax. Sometimes a local tax is also applied. Any attempts to raise the Federal Tax gets shot down by politicians who live in States which have a significantly higher State tax.

Note: The figures in this graph include the across the board 12 cent (or whatever it is) federal tax.