Fuel Vaporization and fuel economy

WHERE is it naturally occuring? I know there is free hydrogen in outer space, but extremely little here on earth. On earth if is too reactive and is combined with other elements in compounds. The very fact that you get a lot of energy from combining it with other elements means you need a LOT of energy to get it back free again.

I think hydrogen would be a GREAT vehicle fuel once someone comes up with an economical way to generate/liberate hydrogen. Till then, however, not much usefulness.

I think the government and auto research labs should be working much harder on this "source" of hydrogen than on fuel cells. We don't NEED fuel cells to use hydrogen in automobiles. Current IC engines can readily be adapted to burn hydrogen, with same favorable environmental impact.

The main thing you are compressing inside the cylinder is air. The fuel is by percentage only about 1/15th of what you are compressing. So the state of the fuel has little bearing on the compression.

The only time when there is a problem is during a starting situation when so much liquid fuel has entered a cylinder that it FILLS the cylinder and you can get hydraulic lock. This is a problem with radial aircraft engines who have cylinders pointed downward, or in race cars that have push starting, but extremely rare in passenger cars.

Hydrogen can be made with electrolysis, but that is a very expensive process. The big problem at the moment, as I understand it, is storing it in a form that isn't explosively dangerous to the public. Remember the Hindenberg.

Lg

The Hindenberg crash was three-quarters of a century ago. We've made great strides in handling hydrogen since then. NASA in particular did very good work- they use it on many launch vehicles and the shuttle. Natural gas and propane are quite explosive too, though not as bad as hydrogen. Still, we use natural gas and propane all the time.

When gasoline was first proposed as a motor fuel many laughed at the idea- way too explosive.

No, we can handle it- the problem is the source. Yeah, you can electrolyze water, but it takes more energy to do that than the energy you get from the Hydrogen. Now, if we ever get a low cost source of electricity, then using electrolysis to generate H2 as transportation fuel would be okay.

The problems with hydrogen are similar to those with natural gas. Storage. Propane and butane liquify at relatively high temperatures and low pressures, so you can take a steel propane bottle that ways 20 pounds or so and fill it with 5 gallons of liquid propane that will run your gas grill for a LONG time (or a 30 gallon bottle that will run your car a LONG time). Natural gas and hydrogen can be liquified, but it takes low temperature and/or much higher pressure, neither of which are practical for on-the-road vehicles. Natural gas vehicles use

*compressed* (but not liquified) natural gas, and the tanks are very heavy to handle the high pressures and they still aren't good for enough fuel to travel long ranges. Its not a safety question so much as it is a question of getting high energy density in the storage tank.

Not to mention that the Hindenberg crash/fire was the aluminum powder in cellulose binder that the skin was painted with, for all intents and purposes the Hindenberg skin was literally solid rocket fuel. Best guess on ignition was corona discharge, actually witnessed by one of the witnesses. Hydrogen burns in the UV and isn't visible to the eye or to camera technology of that era, so the flames seen had nothing to do with the hydrogen. In fact, the slow rate of fall of the airframe was due to the fact that the rubber bladders were withstanding the flames and maintaining their integrity for a fairly long period of time, and when each bladder finally failed from the fire the hydrogen, not having enough oxygen to combine with, simply sailed up through the skin flames until it was far enough above the craft to ignite, where it burned invisibly.

It takes so much disposable and nearly free electricity to make and cryo commercial quantities of hydrogen that it would be cheaper per mile driven to distribute the electricity directly to homes to charge fully electric cars.

The only viable sources for large quantities of hydrogen now and for the foreseeable future are natural gas and related hydrocarbons, which is why Bush wants to develop a "hydrogen" economy, he's just looking out for number one.

JazzMan

What is wrong with metal hydrides for hydrogen storage?