In 1979 Jimmy Carter delivered a televised speech bemoaning the increasing US dependence on foreign oil.  In it he outlines his Energy Policy for the coming decades.

“[Foreign Oil is] a cause of the increased inflation and unemployment that we now face. This intolerable dependence on foreign oil threatens our economic independence and the very security of our nation. The energy crisis is real. It is worldwide. It is a clear and present danger to our nation.”

— Jimmy Carter  (http://www.pbs.org/wgbh/amex/carter/filmmore/ps_crisis.html)

Today the US relies on 60% foreign oil (http://www.fueleconomy.gov/FEG/oildep.shtml) in strong defiance of president Carter’s prescient warning.

As far as the US dependence on foreign oil, nothing has changed since the Carter’s clarion call aside from the problem getting far worse.  However, president Carter didn’t live in a world threatened by Global Warming (at least it wasn’t commonly known).   President Carter also didn’t live in a world with two superpopulations, India and China weighing in at a billion people each who are poised to ramp up their consumption.

Clearly oil will no longer do as a source of energy.  Luckily science has provided an alternative: The Hydrogen – Aluminum Cycle.  To be clear, I’m not speaking of hydrogen power alone.  Hydrogen power alone is a red herring of alternative energies.  The catch is that hydrogen is hugely expensive to make and today largely comes from the demethylization of hydrocarbons; ie oil.  No, the Hydrogen – Aluminum cycle is something different entirely.

When we think of hydrogen, some horrible images from the past might emerge.

Here we see the Hindenburg which was filled with hydrogen bursting into flames.  Many see the risks of hydrogen in cars and decry ‘oh the humanity!’.  Well there are no such worries with the hydrogen – aluminum power cycle because the hydrogen is produced in micro amounts and only as needed.  Hydrogen need not be stored in a cryogenic canister with motorists barrelling down the highways with a bomb on board.  This in situ or just in time production solves the danger of using hydrogen in a car.

Next, we must solve the problem of where to find our hydrogen.  Clearly deriving it from oil simply won’t do.  The other current method for obtaining hydrogen is through a process called hydrolysis which splits water into hydrogen and oxygen.  Regrettably, this process is too inefficient to be used on a wide scale.

Enter into the picture aluminum.  Aluminum has a high affinity for oxygen.  Whenever you hold a piece of aluminum it has a skin of oxidation.  This skin, once formed, prevents any further oxidation which is why you never have to worry about rust in components built of aluminum.  Aluminum likewise reacts with water;  A jealous lover of oxygen, it bonds strongly with it, ousting the hydrogen.  While a jealous lover aluminum may be, it is quickly satiated and forms a skin failing to react any further.

Jerry Woodall, a professor of Computer Science and Electrical Engineering at Purdue, discovered in the 60’s that when aluminum, gallium and water were mixed, the aluminum oxidized fully, liberating massive amounts of hydrogen.  It would seem that the gallium acts as a mediator in the reaction and prevents the formation of the oxidation skin on aluminum.  The end results of this reaction are hydrogen gas, aluminum oxide (aka alumina) and gallium.  The gallium is not consumed, and thus can be recycled.  The alumina can be electrically converted back into aluminum and thus recycled.  Burning hydrogen produces only water.

The idea of using hydrogen to power a vehicle is certainly not a new one.  While Woodall was experimenting with gallium in the 60’s, GM was trying to prototype a hydrogen fuel cell vehicle: The Electrovan.  It is recognized as the first hydrogen fuel cell prototype.  The prototype was scrapped due to the high cost of the rare (precious) metals used in its fuel cells and the complexity of storing hydrogen.

The aluminum-gallium-hydrogen cycle may allow us to succeed where the Electrovan failed.  So now, let’s put the pieces together: How does this get you to work in the morning?  Your new, non-polluting car has two fuel tanks, one containing water, the other containing aluminum and gallium flakes.  As hydrogen is needed the water and the flakes are mixed.  The hydrogen is harvested and runs the engine.  Also the heat produces by the chemical reaction may be harvested for energy by a Stirling Engine which is a type of engine which can run off of temperature differentials.

When it comes time to fuel your vehicle, the new filling station attaches three hoses to your car.  One removes the slurry of used alumina to be recycled.  The other two replenish your supply of water and aluminum-gallium flakes.  When it comes time to pay for your aluminum flakes, will it be competitive with gasoline?

“Since standard industrial technology could be used to recycle our nearly pure alumina back to aluminum at 20 cents per pound, this technology would be competitive with gasoline,” Woodall said. “Using aluminum, it would cost $70 at wholesale prices to take a 350-mile trip with a mid-size car equipped with a standard internal combustion engine. That compares with $66 for gasoline at $3.30 per gallon. If we used a 50 percent efficient fuel cell, taking the same trip using aluminum would cost $28.”

—  (http://www.purdue.edu/UNS/x/2007b/070827WoodallNanotech.html)

Next, some may wonder where the aluminum will come from.

Enough aluminum exists in the United States to produce 100 trillion kilowatt hours of energy. That’s enough energy to meet all the U.S. electric needs for 35 years.  If impure gallium can be made for less than $10 a pound and used in an onboard system, there are enough known gallium reserves to run 1 billion cars.”

—  (http://www.purdue.edu/UNS/x/2007b/070827WoodallNanotech.html)

Recall that alumina (aluminum oxide, the waste product) can be recycled electrically back into aluminum.  So it’s not like oil where, once burnt, we can’t reclaim it.  We can electrically reclaim the waste alumina back into aluminum.

Ecologically this is a dream come true.  When thinking ecologically it’s important to think in terms of cycles.  Everythings output must be something’s input cycling back to the original source.  Here we have aluminum going to aluminum oxide (alumina) going back to aluminum.  The alumina to aluminum step can be powered by non polluting nuclear or renewable sources such as solar or wind etc.  The water turns to hydrogen which combines back with oxygen to produce water.  Gallium is never consumed and is recycled continuously.

So there you have it: president Carter’s dream some thirty years later, but not too late.  With the skyrocketing prices of oil the need for this change has never been more clear.  The only missing ingredient in this equation is the political motivation to fund and accelerate the conversion process.  This may prove to be the trickiest part of the equation to balance.

Further reading:

Please don’t take my word on this matter, feel free to do your own research:

http://www.google.ca/search?hl=en&sa=X&oi=spell&resnum=0&ct=result&cd=1&q=aluminum+gallium&spell=1

http://youtube.com/results?search_query=aluminum+gallium&search_type=

There is also a similar approach using boron

http://www.google.ca/search?hl=en&q=boron+hydrogen+car&meta=