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Hydrogen Fuel Cells Running On Sunflower Oil
tigersaw writes "You've heard about Biodiesel , Greasecars, and Fuel Cells for a while now. At yesterday's meeting of the American Chemical Society, researchers from the University of Leeds in England described a novel approach that combines these ideas in a fuel cell device that employs steam and two separate catalyts to generate hydrogen using sunflower oil. Experimental results show a hydrogen yield of 90 percent, versus 70 percent in other hydrogen fuel cell technologies. 'The sunflower oil used is the same type found on grocery shelves. "We would happily toss our salad with it," says the researcher, who adds that the process can also work with other types of vegetable oils.'"
I disagree. On Alan Alda's "Scientific American Frontiers," they showed a novel approach in which hydrogen is produced "on site." That is, it uses a reverse fuel cell in every "hydrogen station" to develop hydrogen, then it is liquified, and delivered via hydrogen pumps, much like the way you pump gas, but with a slightly different hookup. That, in my opinion, is a better means of distribution as it completely eliminates the need for transport, pipes, large factories, and so forth.
A blog like any other.
But where does the energy to make the H2 come from? Currently, it takes a cubic assload of electricity to generate hydrogen, so the distributed production model would need huge increases in the electrical power generating infrastructure, which is already near maximum utilization.
The alternate is producing the H2 at a location with cheap power (hydro, desert solar collectors), and then shipping the H2 where it needs to be. But that has its own issues, as you pointed out.
I'll be honest - I'm not holding out for the "hydrogen economy" in my lifetime. Sounds to much like shale oil - grand idea, sounds good politically, and goes precisely nowhere. (Kind of like Carter's other big idea - Middle East Peace)
"As God is my witness, I thought turkeys could fly." A. Carlson
You don't know? Didn't even stop to ask?
I didn't think so.
Being a wet blanket bugs me sometimes, but somebody has to do the dirty work of dragging everything back down to earth and facing facts. Here are some:
- The reactor doesn't generate hydrogen with 90% efficiency, it generates hydrogen of 90% purity. Given that the off-gas is about half methane (RTFA) it appears to me to be very inefficient. (Note: neither the author nor your Slashdot editor bothered to RTFA either.)
- There are already engines, and even fuel cells, which can burn hydrocarbons directly. Sunflower oil makes reasonable diesel fuel as-is. Solid-oxide or molten-carbonate fuel cells can reform fuels internally, and while they might coke up on straight sunflower oil they'd probably work just fine after it had been steam-reformed a bit.
- Hydrogen as a motor fuel suffers from huge problems with storage. People see it as sexy but for all the wrong reasons.
I could see this as another technology for making compact laptop power supplies whose fuel couldn't be used to bring down an airplane (just TRY making a fuel-air bomb with sunflower oil). The key to renewable energy? Gimme a break.Time is Nature's way of keeping everything from happening at once... the bitch.
one point to filter for emissions
That's not necessarily a good thing. Basically you would be concentrting all of the resulting pollution in one area instead of spreading it out more or less evenly. Assuming nature cleans up the pollution at a certain rate (say, as by density of plant life and large bodies of water to absorb and recycle CO2) then you actually made the problem much worse in some areas.
no car pollution in cities
Ah, well, as long as it's not in your back yard I guess it's okay then!
an easy upgrade path when you replace your coal plant with biodiesel or solar or fusion or whatever
Except that the existing power distribution system is already strained and aging such that it can barely keep up with peek demands today. It would cost billions upon billions to construct new powerplants and additional infastructure to handle the additional demand of the now millions of electrical vehicles feeding off of it.
possible economies of scale
See above. In general you try not to build powerplants too far from where the power is used (obvious?). And you will definately need more of them right from the start.
Now take a straight biodiesel economy model:
Virtually no infastructure costs. Everything you need to produce, transport and distribute liquid fuel is already in place.
Less pollution on the grand scale. BD burns cleaner than the oil and coal (especially coal) used in powerplants, and the resulting pollution is spread out evenly such that nature can process it more effectively. If you're worried about soot (which BD produces less of anyway) there are already very effective filtering systems for small vehicles in widespread use.
Excellent scaling economics. Unlike electricity you CAN produce/refine all of the BD in one spot for the entire country (even though you probably wouldn't want to). There is basically no restriction on the location of the refineries, and the distribution infastructure of trucks, boats and pipes is more flexible than high voltage transmission lines.
The only problem is "where does te energy come from in the first place?", which the centalized electric system doesn't address either. Fusion power has to actually exist before you can even consider it, and all of the other possibilities such as oil, coal and nuclear all rely on the very same sources we're trying to get away from.
I have read articles about the possible use of algae for BD production. According to the article (which I found a version of on google) you can farm a high-oil content algae species for the purpose, which eliminates basically all of the problems of cultivating and fertilizing land for growing plants (algae doesn't need tilling...) Simply excavate a shallow lake somewhere relatively low and let gravity fill it with seawater, then start growing. If you're clever you can use a system of dykes to let the tide purge the lake for you and filter off the algae as the lake drains. Then you run it through a giant juicer and add a little methanol and lye to remove the glycerin from the product, and you got Biodiesel ready to burn in just about any existing vehicle.
=Smidge=