Inorganic Chemistry - Hydrogen Economy

Wait, as in hydrogen fuel? Please report back with the clarification.

yup as in a fuel.

Here's a comparison of hydrogen fuel and fossil fuels.

Production

Hydrogen readily combines with other molecules. The three ways generally used to liberate hydrogen are: using heat and catalysts to “reform” hydrocarbons or carbohydrates; electricity to split (electrolyze) water; experimental processes based typically on sunlight, plasma discharge or microorganisms. Fossil fuels are non-renewable source of energy. They were formed from the organic remains of prehistoric plants and animals and have been transformed into to carbon-containing fuels by geological action over millions of years.

Emissions

Hydrogen-fueled vehicles emit no greenhouse gases or other pollutants. During combustion, hydrogen produces only water vapor. On the other hand, the combustion of fossil fuels is the largest source of atmospheric pollution. Combustion of coal and petroleum are said to be responsible for the release of greenhouse gases such as carbon dioxide and nitrous oxide into the atmosphere.

Efficiency

Hydrogen fuel is very efficient. More energy is extracted from this fuel source than with conventional power technologies, according to Tobin Smith for Billion Dollar Green. Fossil fuels have a high combustion rate and are capable of releasing tremendous amount of energy.

Cost

Hydrogen is currently expensive because it is difficult to generate, handle and store. Fossil fuels are less expensive in comparison.

Future

Fossil fuels serve as the primary source of energy at present. However, fossil fuel reserves are gradually depleting. Although hydrogen fuel is being used on an experimental level at present, it has great potential for the future.

You raise scientifically complicated and politically charged issues. Hydrogen is presented as the "clean burning" alternative for fossil fuels, but the dream is neither so simple nor clear. Put aside for the moment that the technology of producing, storing, distributing, and burning hydrogen (in air) is not in place and the associated engineering problems and economics are daunting. A few examples fished from a large school of problems. Hydrogen has very large flammability limits. That's good news in some respects, but it also places tight constraints on engine design, because "hot spots" in the cylinders (assuming an internal combustion engine) will result in pre-ignition, "pinging" as it is known in the hydrocarbon world. The flame temperature of the combustion of hydrogen is higher than hydrocarbon fuels. This high temperature (in principle) is a benefit, but since air is 80% N2 the high temperature can result in the formation of higher levels of nitrogen oxides. That is the bad news. Just how enough H2 can be manufactured economically, and the infrastructure to distribute it nationally, even globally, is unsolved. If you compare H2 to CH4 on an equal mass basis it appears that there is a 16/2 advantage (the molecular weights) in favor of hydrogen; however, on an equal energy basis: H2 + 1/2O2 = H2O compared with CH4 + 2O2 = CO2 + 2H2O all components in the gaseous state the advantage is only ~ 3.6 because considerable energy is derived from the formation of CO2. But I am saving the best (or worst), and most neglected issue for last. One that has been neglected, like the proverbial elephant in the living room. WATER IS A POTENT GREENHOUSE GAS. I have searched in vain for climatological studies that have factored in the effect of the release of millions of tons of water vapor into the atmosphere. We may be trading smog for fog! The hydrogen age is politically correct these days, but the scientific and engineering realities are being swept under the carpet.

what other alternatives do you guys suggest other than the use of hydrogen as a fuel.
May be ethanol?

Yeah or biodiesel.