The problems with the fossil fuel economy are so great, and the environmental advantages of the hydrogen economy so significant, that the push toward the hydrogen economy is very strong.
Where does the hydrogen come from?
In the hydrogen economy, there is no storehouse to tap into. We have to actually create the energy in real time. There are two possible sources for the hydrogen.
Electrolysis of water-Using electricity, it is easy to split water molecules to create pure hydrogen and oxygen. One big advantage of this process is that you can do it anywhere. For example, you could have a box in your garage producing hydrogen from tap water, and you could fuel your car with that hydrogen.
Reforming fossil fuels-Oil and natural gas contain hydrocarbons-molecules consisting of hydrogen and carbon. Using a device called a fuel processor or a reformer, you can split the hydrogen off the carbon in a hydrocarbon relatively easily and then use the hydrogen. You discard the leftover carbon to the atmosphere as carbon dioxide.
The second option is, of course, slightly perverse. You are using fossil fuel as the source of hydrogen for the hydrogen economy. This approach reduces air pollution, but it doesnt solve either the greenhouse gas problem (because there is still carbon going into the atmosphere) or the dependence problem (you still need oil). However, it may be a good temporary step to take during the transition to the hydrogen economy. When you hear about fuel-cell-powered vehicles being developed by the car companies right now, almost all of them plan to get the hydrogen for the fuel cells from gasoline using a reformer . The reason is because gasoline is an easily available source of hydrogen. Until there are hydrogen stations on every corner like we have gas stations now, this is the easiest way to obtain hydrogen to power a vehicles fuel cell.
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