There's been lots of talk about ethanol as a fuel, but I think we'll find that it really won't be viable due to almost all of the ethanol being made for fuel uses corn as a feed stock. Let's face it, corn is one of the worst sources for ethanol. For all of the energy put into ethanol production, we only get a little bit above that amount back in useful fuel.
Ethanol from cellulose-based feed stocks is a great idea, except that no one has figured out how to do that on a large scale. It's still in the lab and not likely to be out there any time soon. But once it is, ethanol will be cheap to make and the amount of fuel gained from the process will be many times the amount of energy put into the process. But like I said, it ain't there yet.
A number of the automakers have been working on fuel-cell powered vehicles. They don't pollute, they're quiet, and extremely efficient. One of the biggest problems with using fuel cells is the fuel - hydrogen.
Producing hydrogen in large amounts is feasible, but not cheap or easy. One of the most common feed stocks for hydrogen production is natural gas. It kind of defeats the purpose of trying to go green if our green fuel uses hydrocarbons pumped out of the ground as a source.
But what if there was a cheaper way of making hydrogen using one of our most abundant resources instead of one that will, at some point, become less plentiful and more expensive? What if all it took was water and sunlight to generate hydrogen?
The Materials Research Institute at Penn State University has been working on a means of using sunlight to separate the hydrogen and oxygen in water.
Most current methods of hydrogen production split hydrogen from natural gas in a process that produces climate changing greenhouse gas while consuming a nonrenewable resource. A more environmentally friendly approach would produce hydrogen from water using the renewable energy of sunlight.
In a paper published online in Nano Letters on July 3, 2007, lead author Gopal K. Mor, along with Haripriya E. Prakasam, Oomman K. Varghese, Kathik Shankar, and Grimes, describe the fabrication of thin films made of self-aligned, vertically oriented titanium iron oxide (Ti-Fe-O) nanotube arrays that demonstrate the ability to split water under natural sunlight.
Previously, the Penn State scientists had reported the development of titania nanotube arrays with a photoconversion efficiency of 16.5% under ultraviolet light. Titanium oxide (TiO2), which is commonly used in white paints and sunscreens, has excellent charge-transfer properties and corrosion stability, making it a likely candidate for cheap and long lasting solar cells. However, as ultraviolet light contains only about 5% of the solar spectrum energy, the researchers needed to finds a means to move the materials band gap into the visible spectrum.
Being able to generate hydrogen by doing nothing more than filling a tank with water and sticking it out on the sun would certainly make the problem of how to provide fuel cells with hydrogen a lot less daunting.
While there are still still details to work out, Penn State scientists believe that they can solve the problem of making the photoelectrolysis process more efficient. Something like this can make the replacement of the petroleum economy with the hydrogen economy far more likely. Using petroleum for fuel seems so wasteful when there are better uses for it, like plastics, lubricants, and other materials.
It can't happen soon enough for me.