Usualy when people takt about future energetic they mostly expect it to be hydrogen based.

I dont understand why there is such impression that hydrogen is best way to store energy?
Can you imagine hudrogen car? if it will use internal combustion motor, total efficiency of all sytem will be less than 100 year old steam machine.
if you use fuel cells it will be simple electric car.

Alsmost everyone knows how hard is to keep and use hydrogen, and how incredibly dangerous it is. Not to mention that you must waste lots of energy just to store it.

We have so many alternatives to hydrogen, zinc-air batteries, flywheels, supercapacitors,High Temperature Batteries, we can aslo easily convert hydrogen to something more usable like gasoline, but none of them bet any significant atention.

Zinc-air batteries are almost perfect even now, all we need is recharge stations, but goverment and media still just talk about some future hydrogen cars, when everything we need is ready for few years already. Do they expect we will drive bombs in future, and explosions that we see in movies will become reality?

I don't think that they are saying it is the best way to store energy, it's just a better way than fossil fuels. It is good because the infrastructure and technology to utilize hydrogen based fuels is a close match to what already exists.
Plus; if you can get enough electricity from alternate non-polluting, renewable resources, then the source of hydrogen is simply water. Until that time, hydrogen can be generated by other means while other methods and infrastructure are being refined.
In the mean time, I think the Hybrid will bring us closer to the electric car.
As Bill Murray says "Baby Steps".

Actually Hydrogen Gas is much safer then Gasoline Vapor.

1 cup of Gasoline, turned to Gas(Fumes) in normal air, will explode when ignited with the force of 5.5 sticks of TNT. The same about of Liq Hydrogen turned to Gas, will burn fast, with about the force of 1.3 Sticks of TNT.

The reason Hydrogen is the appealing choice right now, is that burning it produces a waste product of water.

Where as burning gasoline produces waste products of CO, CO2, NO, HC2N2

Using Hydrogen/Methane/etc in fuel cells isn't that appealing anymore either as it's waste product is heat and CO2.

The other advantage to Hydrogen, is that most gas stations (70%) in the States have LP (liquid Propane) dispensers. It would be a minor matter to change those to dispense Liquid Hydrogen.

__________________
"There is no problem that cannot be solved by a suitable application of high explosives" - US Army Demolitions School

http://worldsofothersuns.home.comcast.net/

Another safety advantage of hydrogen is the fact that if it spills it will quickly dissipate into the atmosphere - the vapors, being lighter than air, rise upward away from the vehicle which greatly reduces the likelihood of burning to death inside a car after an accident.

Hydrogen in an internal combustion engine is a very inefficient use of hydrogen since IC engines only get about 25-35% efficiency. A fuel cell on the other hand has efficiencies of about 90% and so the energy, as represented by hydrogen, is much better used by a fuel cell.

The above listed alternatives are even more limited in scope than hydrogen being used in a fuel cell driven vehicle.

One other thing about exposiveness/flamability of hydrogen: the Hindenburg burned because of the coating applied to the fabric rather than because of the hydrogen. If hydrogen were the main source of fuel in that tragedy then the flames would have harmlessly shot upward with the rising hydrogen gas.

It will be quit hard to vaporize 1 cup of gasoline,and if you spill liquid hydrogen you can expect it to vaporize at once.
also this your argument is against hydrogen usage, because you will need 4 cups of liquid hydrogen for same energy which you can get from 1 cup of gasoline.
you will be forced to store hydrogen under extreme presure, or in cryogenic temperature. botw are terribly dangerous, if some accident will happen results will be worse than suicide bombers can do.


no, NO will be produced with hydrogen too. also CO2 is not so harmfull anyway. just plant more trees and get rid of excess CO2.
m aibe you expect less heat with hydrogen? what about this that first you make electricity of some nuclear rection, efficiency is about 40% , next you make hydrogen from water efficiency somewhere about 90% then you store that beast wasting nearly 20% or more, then you burn that precious product with efficiency of 20% to drive yor car. I expect at least 2 times more heat than from gasoline.
Not so minor, propane is liquid at room temperature, and hydrogen is the hardest gas to liquify in universe. Actualy you can use propane instead of gasoline in Siberia, since it will liquify naturaly in winter time.

You shoudl not mistake hydrogen as fuel, it is just for energy storage, we have no hydrogen sources, or you expect some perpetual motion enzyme which splits water into O2 and O2 ?
all tecnology is totaly diffrent, and very lossy.

ok, imagine this scenario car hits something at 100km/h speed in town. Quite likely that will be another car. if we use high presure tanks then you can expect them to explode and release all gas. it will be enough energy for small explosion even if hydrogen will not ignite.
Or if we use cryogenic srorage, prepare for 5% loss of fuel each day.

ok what wrong with alternatives? hydrogen cant be used in combustion engine anyway, if you care about efficiency.

Not on this forum, nor anywhere where "people" are informed about the matter.
In my experience, the people most enthusiastic about hydrogen do not even realize that hydrogen is energy storage, not energy source.

__________________
Fiction has to be plausible. Reality is under no such constraint.

Of course! Why hadn't we thought of this before. Now if only we can put an end to the world's dependence on wood and wood products. And I'm sure the loggers will stop cutting down forests if we just tell them we need the trees as CO2 scrubbers, they'll be reasonable and listen.

Oh wait, nevermind.

Maybe we should make giant Lithium Hydroxide canisters instead. It seems a bit more plausible

__________________
I was just sitting here contemplating the immortal words of Socrates who said, "I drank what?"

"Think of the rivers of blood spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot." --Carl Sagan "Pale Blue Dot"

no, NO will be produced with hydrogen too.

How do you figure that?

if you use fuel cells it will be simple electric car.
.....We have so many alternatives to hydrogen, zinc-air batteries, flywheels, supercapacitors,High Temperature Batteries

Let's do a little thought experiment here. Say we both have get give a brand new Tesla Roadster. Yours is the standard package, lithium batteries, 250 mile range. Mine is modified a bit, I have fuel cells, but the same range. Off we go. Fine and dandy, we can hoon along the interstate at 70 mph until... Oh dear our charge is running low. Quick best pull into the energy station and recharge. You plug in your car and buy a good book because you're going to be sitting there a long time. I simply simply attach the line of CHG (compared to CNG) and refill my fuel cells, wave goodbye and carry on.

Now of course there is a slightly different option in that I can just opt for a standard car modified to guzzle Ethanol instead of Petrol, cheaper green and better all around.

As to CHG being a danger, no more (in fact less) than CNG and that has been powering vehicles for years without them all blowing up, even in accidents.

__________________
Howling from the Shadows

It must be fun to lead a life completely unburdened by reality. --- JayUtah

You can't reason an irrational person out of an irrational belief. --- Noclevername

Apollo: The History and the Hoax
Enter the World of Athran

I doubt hydrogen will ever take off for use in cars. If I want to cut down on fossil fuel use and reduce CO2 emissions I can use a hybrid. If I use one that gets about 30 kilometers to the liter under normal driving conditions then I will emit about 380 kilos of carbon a year. Paying to lock up that carbon from the atmosphere might increase my gasoline bill by about $40. A plug in hybrid that enables me to use grid power around town would save even more fuel and lower the cost of locking up the resulting carbon even more. And none of this requires any additional infrastructure to be built.

Hydrogen seems to be presented as an alternative product for the oil companies to evaluate. Who else would have the infrastructure and money to go in this direction?
Yes, hydrogen used in an IC engine will produce NO (unless we get oxygen into the game, and leave the air alone!). However, I never heard that a fuel cell will produce CO2 from hydrogen. Where does this carbon come from?

Compressed hydrogen is not the preferred means of storage. Lithium hydroxide is one of many non-pressurized systems considered, but the advances in graphite storage looks much better. Hydrogen can be safer than gasoline.

Propane is liquid at room temperature? Only if your room is at -42c!

Yes, zinc-air batteries (with solar panels!) would be a fantastic means of propelling our vehicles, but there's that charge-time previously mentioned that's going to be a big problem.

Most likely hydrogen will eventually replace gasoline. However, the price will have us longing for the good-old-days when we were only paying $3 a gallon for fuel.

There are other alternatives. One is hydrazine. It's not too difficult to produce, and combustion produces water and CO (and likely NO as well). Also, it sounds more COOL!

Not really. You get more energy per unit of pollution from regular gasoline than you do from burning ethanol. Also, you have to make the ethanol, which creates as much pollution as creating gasoline.

Digix, there are many people working on this because there are good reasons to use hydrogen. Typically, they don't store it as H₂, but as something like diesel fuel or methanol. I'm not certain what current commercial models (like the Vancouver bus cells made by Ballard) use, but it's generally not compressed hydrogen. So there isn't much of a safety factor, nor do you lose fuel over time, as you suggested. A lot of research goes into finding better ways of storing hydrogen... if only we had a huge supply of palladium....

The biggest reason has been mentioned: efficiency. Conversion of power from the grid into fuel through water electrolysis is very efficient. (I think I read that there's a team which is going to take a boat around the world next year just on hydrogen cells, using solar to build up hydrogen reserves during the day, and using that power during the night.) In addition, vehicles that can use regenerative braking are efficient -- you can't do this well with most gas-powered vehicles. Finally, conversion of hydrogen fuel into useable energy in the engine is efficient.

Currently, most hydrogen is made from hydrocarbon fuels, so there isn't much environmental benefit there, but the idea is that it is possible.

__________________
"It's turtles all the way down."

Because you could say you're running your car on rocket fuel!

How does hydrazine produce CO? Where does the carbon come from?

__________________
"It's turtles all the way down."

If hydrogen is so expensive we'd be better off without it. I could drive a plug in hybrid off electricity around town and then use whatever was the cheapest liquid fuel on longer trips, whether it be made from coal, plants, sewage, petroleum, or whatever. Carbon released from using fossil fuels could be trapped at a cost of perhaps 4-10 cents per liter of fuel.

If you feed it to an IC engine, you'll get NO the same way as with hydrocarbon fuel. Obviously, it isn't an issue with fuel cells.

As I've mentioned before, I suspect that a methanol economy - methanol produced using hydrogen and other carbon sources (atmospheric CO2, among other things) would have an advantage over a hydrogen economy. It's a more compact fuel, easier to handle, can be easily worked into the current infrastructure and can also be fed to fuel cells.

__________________
I say there is an invisible elf in my backyard. How do you prove that I am wrong?

Disclaimer: Avatar is not an official NASA image and does not imply any specific interplanetary or interstellar capability.

The Leif Ericson Cruiser

Using hydrogen in an Internal Combustion engine is a possibility but not an attractive one considering the net efficiency:

45% - efficiency of electrical power generation
90% - efficiency of electrolysis
30% - efficiency of IC engine

Net Efficiency:

45%*90%*30% = 12.15%

I read of using electricity to create "manufactured" gasoline to burn in IC engines but even if the gasoline making process were 100% efficient it would only have a net efficiency of:

45%*100%*30% = 13.50%

Using any of the above two schemes with IC engines would require double the energy production from the electrical grid as currently delivered from the oil industry.

You think wrong. Lithium hydroxide is good way to store hydrogen , but it will be super expensive, and basicaly you will have LiION battery or we may call it LiMH-air battery, I think NiMH batteries are cheaper, and they use exact same way.


Each gas have critical point, for propane this temperature is far more than room temperature so all you need ir to create moderate presure. for example water have critical temperature about 500C for ptopane it should be more than 100C

hydrogen temperatures are far below anything tha can be created without multistage cooling systems.

zinc-air batteries are not rechargeable, you must replace containers with zinx to recharge. or also you can use some zinc emulsion which you fill into your fuel tank.

Any engine which have high termperature + high presure and uses air will produce NO


First hydrogen will cost more than electricity. If I use zinc-air battery, all I need to do is replace used zinc containers, or refill zinc emulsion, and give my used ZnO to recharge station. Within 10 min I will be ready to continue trip.
not even specalized recharge station is required, any supermarket will be ok.

And if you will require hydrogen refil, expect to go into something similar like nuclear weapon storage, dangerous zone with high security. I dont think you will easily find places to recharge. Or they will be neat targets for terorists.
I dont know if you will be even alowed to enter hydrogen station area.

If you expect hydrogen to be storen in hydride form then it is already done we have NiMH battery example, of course we can modify them to Air-MH battery which will be same as zinc-air, but I wonder why care nickel balast when you can use zinc and store far more energy in same weight.

Anyone who expects IC engine with hydrogen must be insane, because of incredibly low efficiency.