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Posted on 05/17/2007 4:09:52 AM PDT by saganite
Mass produced solar produces about 100 watts/square meter when the sun is shining. Maybe about 1kwh per square meter/fair whether day. You are not going to make much aluminum with that.
You also need to heat the ore to melting point before electrolysis requiring some sort of fuel.
Transportation is going to require fuel.
Also figure that PEM fuel cells are less than 50% efficient.
You are going to end up with less than 400 watt hours per square meter/ day of solar panel to drive you car. That might get you about a mile and a half down the road.
I’m pretty sure that they’re not talking about using this as a fuel (expended), but like a battery (recharable). Hydrogen likes to get absorbed into metals. The challenge for storing it is on a number of fronts:
* How dense can you store it?
* How much energy does it take to get the hydrogen in?
* How much energy does it take to get the hydrogen out?
* How much does the medium weigh?
* Is the storage medium safe?
* How expensive is the storage medium?
The first three are the really big challenges. It’s hard to get a nice combination of all three. There’s another implied issue which is that, in general, the more you want to get out (or in), the more energy it takes to do so. So, for example, you might have a material that stores plenty of hydrogen, and doesn’t take much energy to store or retrieve it... but only for, say, 10% of the hydrogen that you’ve stored. Want to take more in or out, you have to expend a lot more energy.
That just may be. But the headlines are "run your car on water". That strongly implies free (free as water) energy, no more need for gasoline
Bookmarked
You can do the same thing with Freon, and you don't have to worry about poisonous clouds of vapor, should you spring a leak.
. . . but you sure would need electricity from somewhere, which is not true of the use of gasoline.
Been thinking about this all day, as I was “solar collecting” with a chain saw. Question : does the gallium, with a 30 deg C melting point reduce the Al melting point at 660 deg C, by some sort of diffusion process? If so a possible use : emergency home generator package-system. Let’s say you save up over the years, some 20,000 # of Al cans, scrap. That provides, at 1KWH/.5#, power for nuclear winter(42 months).
Then you have a fuel cell that lasts those 3.5 years. Of course you’d have to learn how to recycle the pellets yourself, and the unit would be in your(well insulated)living space. Does this start to make sense, or would good old lye be a better cost option than trying to recycle gallium on your own?
1 KWH/HR isn’t a whole lot of energy but perhaps enough for a submersible well pump(water source), HWH, a few lights, ref...and process heat WARMTH.
I helped out Dr Woodall on this project for awhile. I built the first pressurized hydrogen generator for him from a new Freon “recovery” cylinder.. It is essentially a BBQ propane cylinder, but about half the size. Your idea for an emergency home generator is a good one and that is what Algalco (the startup co.)is currently doing as a demonstration project for the process.
Some engines have a few issues (but solvable) running
on hydrogen. Mainly
1) tendency to backfire..can be reduced by such things
as changing valve timing (so intake and exhaust valves
don’t open at the same time), putting a “screen” to
prevent flashback in the air intake manifold. Others
have used water injection spray to prevent backfiring
and prevent NOx formation when running ICE engines
on hydrogen.
2) hydrogen is less dense than gasoline, so engine
(non turbo) will only deliver around 70% of the horse
power as it does on gasoline. not an issue for turbo.
3) Way to safely deliver the H2 to the engine and
carburation. Use propane carb, etc. Need safety system to
shut off H2 flow incase engine stops for some reason
like low oil, etc. In the lab, you can just stick an H2
hose in the air intake of a gasoline generator and pull
the cord.. fires right up. Gasoline vapor in air has
in ignition range of about 2-8% (volume) in air. H2 is
around 4-75% in air. Engines on H2 can be idled down
to very low rpms and still keep running.
Due to H2 high ignition range, engine can run very
lean for good economy. However, you must watch the EGT
(exhaust gas temp) and avoid high power operation
when lean, since the excess hot O2 in the exhaust
will burn the valves. I lit a charcoal Grill with LOX
and can assure you that steel burns like magnesium in
hot oxygen.
Diesel.
Others have shown that diesel engines will run well
injecting H2 into the air intake. They still need
around 10% diesel to provide reliable ignition, but
can have about 90% of their power from H2 with little
if any modifications. My personal opinion is that this
hydrogen system may be well suited for Diesel
locomotives and long haul diesel semi trucks.
Pretty much all that is needed is a separate hand
throttle, to control H2 into the air intake, and
leave your foot off the pedal (so it runs at idle
diesel with upto 90% from the hand throttled H2)
see http://hydrogen.ecn.purdue.edu
—ghg
Well, good for you, a DOER in the energy sector, developing new concepts. Did another BOTE calc : if gallium costs $180/# and aluminum(retail)$1/#; and 1# of Al produces 2KWH, and I only need 1KWH in survival mode with a home emergency generator, that’s 12# consumed for a 24 hr day. That in turn requires some $2160 for the gallium to start with, assuming a 1:1 alloy ratio, and being a metallurgy guy each and every DAY recovering the Ga and recasting into beads of alloy, ie, a SLAVE to the thing.
For say 3 years of operation and 12# of Al/day = 13,140# of Al. That works out to about a 4’4” solid cube of Al, or a big pile of scrap aluminum. Since scrap aluminum is MUCH cheaper than ingots = save up your old beer/soda cans by shredding them for the next few years.
That still leaves the problem of recycling the gallium into the Al/Ga alloy, obviously everyone is not suited to be metallurgy workers. Sure, the Ga comes out of the white rust Al2O3 at 30 deg C melting point, but Al’s M.P. is 660 deg C = some kind of small home recycling furnace, something your aunt millie can’t do.
That then suggests the alternate lye-in-water on shredded beer cans approach, I’ve done that myself, it works. On a $ per $ basis, which wins as the best H2 producer? Lye certainly doesn’t cost $180/#, esp in bulk prices.
Then there’s internal combustion engines vs fuel cells, which will be the competitive winner there? Personally I’d prefer the H2/air fuel cell as it’s quieter. So is this Ga/Al idea viable, or impractical?
Speaking of diesel semitrucks, an idea I had : aerotails on rear doors to eliminate rear drag, either a balloon or open weave, stretchable fabric for freeway speeds. It inflates above 35 mph, then recollapses onto back doors for slowing to a stop/tight traffic. On a frame that swings 270 deg for loading/unloading. It would boost diesel mpg about as much as the aeroshell-over-cab does, a fish tail to go with that fish head.
I envision a curved pyramid like the rear shroud emplaced on the shuttle for its piggyback ride on a 747. Also google DYMAXION CAR, Bucky Fuller’s 1933 invention of a fish-form car. Some say that the kamm effect means a 30’ to 40’ long tail is required whereas a shorter tail would get rid of MOST of the rear drag, an example of the PERFECT being the enemy of the GOOD. Also note the clam shell tail on the “busted up sky truck” in the movie : Flight of the Phoenix. It certainly isn’t 30’-40’ long....
So, as you follow a semitruck you’ll notice the layer of dust/dirt on the back doors, many see, few PERCEIVE.
Thank you for your educated comments about this technology.
I look forward to seeing more about it as things progress.
Please post articles here, and if you do, please ping me.
What, over 150 posts and no picture of Mr. Fusion!
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Does this not apply as regards the recycling mentioned in this article?
No, the "recycled aluminum" they are talking about is still metallic aluminum.
After going through this process, the aluminum is in the form of aluminum oxide, or like the original ore.
Ga is a “waste” product from Al refining, and
that is highly purified to semiconductor grade
(five 9’s), hence the high cost now. If the Ga
was less pure (prob with the impurity being Al),
it would cost much less. For the home ‘emergency’
system, that sits unused for years, the current
high Ga price bites. If it is used over and over,
like a diesel locomotive, then the cost is amortized
out.
—ghg
We do not produce enough gasoline in America to fuel our ICE cars.
We have coal in abundance. We can build nuclear plants. We have an abundance of untapped wind energy. If direct thermo-electric conversion pans out, even solar would be cost competitive.
As we speak, the first practical solid oxide fuel cells are rolling out of the labs. Combine this with plasma incinerators (a product now on the market) and our refuse stream alone would provide the majority of electricity needed for transportation.
We do not have adequate petroleum supplies but we do have other resources and eventually the market will adjust to that fact.
Gasoline engines are a primative way to power a car. It is so familiar to us that it is hard to stand back and see it that way but it is an overly complex and inefficient. How many moving parts are there in an engine. You have metal banging and grinding away with only splashes of oil and a water jacket keeping the whole thing from melting down. And when your done, you are throwing away 80% of the expensive fuel as waste heat.
There is also the whole fuel infrastructure. You start out with oil in some forsaken part of the globe, pipe it, put it on a boat, pipe it again, refine it, pipe it again, put is on a truck, pump it into a gas station where you have to drive to pump it in your tank.
Your kilowatt of electricity can come from any number of sources and is delivered directly to your house with high efficiency. The electricity is easy to find. It is also a higher form of energy, it is ready to light your house, run your computer or turn a motor without converting it to heat then trying convert that heat into usefull energy.
Your gallon of gasoline could be very hard to find if Iran scuttles a few tankers off their shore or if a third world thug wants to see us squirm and turns off the spigot.
Well then, it remains to be seen what your developers can come up with as a practical, affordable device. Again, powering all VEHICLES with the Ga/Al concept may be too ambitious to start off with, but a reliable home generator unit/system that aunt millie can operate for 3-5 yeas would be a big sales item.
To wit, do some market studies here first before you put all kinds of money into developing specific systems. Technical history is littered with products that missed the mark, there’s even a museum for them. Thus, with any new concept like this, you first nibble off a tiny slice of market share and then build from there. Many, many in the past had delusions of grandeur...and fell flat on their faces...history is a TEACHER, learn from it...
New Catalyst Produces Hydrogen from Water"We have discovered a catalyst that can produce ready quantities of hydrogen without the need for extreme cold temperatures or high pressures, which are often required in other production and storage methods," remarks Mahdi Abu-Omar of Purdue University. The compound he and his colleagues used is a so-called coordination complex based on the metal rhenium. Originally looking for a method to convert chemicals called organosilanes into silanols, the team combined organosilanes and water in the presence of the rhenium complex at ambient temperature and pressure. After an hour, the reaction had produced hydrogen gas in addition to silanols. According to a report published today in the Journal of the American Chemical Society, the method generates a large amount of hydrogen compared to the amount of water used.
Sarah Graham
Scientific American
August 31, 2005
"The big question is, of course, whether it would be economically viable to create organosilane fuels in the quantities necessary to power a world full of [fuel-cell] cars," Abu-Omar says. "As of right now, there simply isn't enough demand to make more than small volumes of this liquid, and while it's a relatively easy process, it's not dirt cheap."
Hydrogen-fuel storage for cars gets a materials boostLast year a team led by HRL's John Vajo reduced decomposition temperatures substantially by adding substances such as silicon to complex metal hydride systems. Such additives act as destabilization agents. "Essentially the metal and the destabilizer join preferentially and displace the hydrogen," explains Leslie Momoda, director of HRL's sensors and materials laboratory. Using magnesium hydride as a destabilizer for lithium borohydride, for instance, lowers the release temperature from 400 to 275 degrees C. Moreover, the hydride can store 9 percent of its weight as hydrogen, beating the oft-cited target of 6.5 percent. She hopes that HRL staffers can eventually identify a "Goldilocks" compound with sufficient adsorption capacity that will release hydrogen at 150 degrees C or even lower. Momoda admits, however, that the hydrogen pickup rate is still too slow; current materials might take 30 minutes to refuel.
by Steven Ashley
Scientific American
June 13, 2005
Sugar: Future Fuel?This new procedure, which produces hydrogen from glucose and related carbohydrates, was developed by chemical engineers James Dumesic, Randy Cortright and Rupali Davda at the University of Wisconsin-Madison. A platinum-based catalyst breaks down the carbohydrates into carbon monoxide and hydrogen gas. The carbon monoxide reacts with water to produce carbon dioxide and more hydrogen. Everything happens in one container, with the liquid solution under pressure at a relatively low 400?F. That, according to Cortright, makes it well-suited for onboard reforming in a fuel cell car; other reforming methods, he says, have required temperatures four times hotter. Glucose is a renewable sugar. It is already mass-produced from corn and can also be derived from many kinds of biomass waste... DaimlerChrysler... points out that "vast amounts of space" would be required to grow enough plants to fuel America's auto fleet. Still, the auto giant is interested enough in the Wisconsin project to provide some funding for further research.
by Paul Beck
February 2003
Popular Science
Researchers envision tiny spheres storing the gas in carsThe research team is getting started thanks to a $2 million Energy Department grant that's part of President Bush's FreedomCar program — a $1.2 billion initiative to develop cars that run on hydrogen-powered fuel cells. The miniature glass spheres, known as microspheres, "are a much safer method for transporting hydrogen," says Jim Shelby, project leader and professor of ceramic engineering at Alfred University in Alfred, N.Y... At 50 micrometers in diameter and with a wall that's less than a micrometer thick, each microsphere contains a minute amount of hydrogen. But trillions can be bunched together to make for a sizeable storage system that weighs much less than a traditional heavy steel tank. Shelby envisions a day when drivers fill up cars with microspheres the way they pump gasoline. "The refueling process would be in two steps. First, a vacuum would suck the used spheres out and send them to a tank for refilling. New, filled spheres would then be pumped in from a different tank," he says... Made of sand, the microspheres are very light, inexpensive, easily recycled "and can be repeatedly filled and refilled without degradation," he adds... Within four years, the researchers hope to have a "tabletop" device that can drive a fuel cell and show that the concept is practical.
by Miguel Llanos
Updated: 11:06 a.m. ET July 07, 2004
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