Posted on 11/12/2007 10:45:42 PM PST by Rick_Michael
CHICAGO (AFP) - US researchers have developed a method of producing hydrogen gas from biodegradable organic material, potentially providing an abundant source of this clean-burning fuel, according to a study released Monday.
The technology offers a way to cheaply and efficiently generate hydrogen gas from readily available and renewable biomass such as cellulose or glucose, and could be used for powering vehicles, making fertilizer and treating drinking water.
Numerous public transportation systems are moving toward hydrogen-powered engines as an alternative to gasoline, but most hydrogen today is generated from nonrenewable fossil fuels such as natural gas.
The method used by engineers at Pennsylvania State University however combines electron-generating bacteria and a small electrical charge in a microbial fuel cell to produce hydrogen gas.
Microbial fuel cells work through the action of bacteria which can pass electrons to an anode. The electrons flow from the anode through a wire to the cathode producing an electric current. In the process, the bacteria consume organic matter in the biomass material.
An external jolt of electricity helps generate hydrogen gas at the cathode.
In the past, the process, which is known as electrohydrogenesis, has had poor efficiency rates and low hydrogen yields.
But the researchers at Pennsylvania State University were able to get around these problems by chemically modifying elements of the reactor.
In laboratory experiments, their reactor generated hydrogen gas at nearly 99 percent of the theoretical maximum yield using aetic acid, a common dead-end product of glucose fermentation.
"This process produces 288 percent more energy in hydrogen than the electrical energy that is added in the process," said Bruce Logan, a professor of environmental engineering at Penn State.
The technology is economically viable now, which gives hydrogen an edge over another alternative biofuel which is grabbing more headlines, Logan said.
"The energy focus is currently on ethanol as a fuel, but economical ethanol from cellulose is 10 years down the road," said Logan.
"First you need to break cellulose down to sugars and then bacteria can convert them to ethanol."
One of the immediate applications for this technology is to supply the hydrogen that is used in fuel cell cars to generate the electricity that drives the motor, but it could also can be used to convert wood chips into hydrogen to be used as fertilizer.
The study appears in the Proceedings of the National Academy of Sciences.
This process produces 288 percent more energy in hydrogen than the electrical energy that is added in the process,
I didn’t say you couldn’t do it just not as well.
Natural gas compresses to a much more energy dense state making useful ammount much easier to store and goes through metal pipes without causing metal to become brittle.
Hydrogen in general is produced where it is used.
If you are looking at using biomass as a gassified fuel, it makes more sense to make methane, propane or butane.
1 watt in and 1 watt out is 0% MORE energy.
1 watt in and 2 watts out is 100% MORE energy.
1 watt in and 3 watts out is 200% MORE energy.
Get it?
At least in this case...
The added energy is chemical energy from the acid that is consumed in the process. The process requires two energy sources to produce the resulting hydrogen, electricity and “aetic acid” (which is probably missing a ‘c’).
;-)
Darn.
Depends on the efficiency of the production process. I doubt that any gasifier reaches the levels of efficiency they quote (though those are likely to go down as the process is scaled up).
"Hydrogen in general is produced where it is used."
Gee, you need to tell Air Products that, they might want to switch from the thousands of cylinders of hydrogen they ship out on a daily basis. In METAL TANKS, no less. Gosh, I wonder why those tanks haven't "gone all brittle" and "lost their hydrogen", since the problems with hydrogen storage are so severe. Excuse the sarcasm, but I get really tired of seeing that bullshit trotted out on every thread about hydrogen. I'll say this one more time---at room temperature, these things are NOT A SIGNIFICANT PROBLEM. At elevated temps, yes, but at ambient temps, the rates are so low that any significant effect would take decades, if not centuries, to show up.
Acetic acid -- the active ingredient in vinegar.
It would make for a long day.
I’ve heard that you can’t control what direction the trip will be.
Bottled hydrogen in a very small part of the hydrogen market.
There is not enough energy in a bottle of hydrogen to be feasable for fuel use.
The hydrogen bottles are designed for hydrogen. Black pipe infrastructure is not.
Hydrogen has many disadvantages and only one advantage. If you believe that man made CO2 is causing global warming then hydrogen allows you to move the CO2 production from the tail pipe to a plant where you can capture it.
Your sarcasm was noted and ignored.
I haven’t read this article yet, but it might be suitable for the renewable energy ping list.
Efficient? Not at all. But as a means to get energy independence it won’t hurt anything but the budget.
This process produces 288 percent more energy in hydrogen than the electrical energy that is added in the process,
Just ignore the man shoveling sh!t into the system.
The aether.
288% more ELECTRICITY than it consumes. The electricity used is just a catalyst to collect the hydrogen after bacteria have broken down the biomass.
It is almost meaningless to even mention the electricity used. It is like saying a gas furnace only uses X amount of electricity. While true, it says nothing about the gas burned to create the heat, only the electricity to run the fans to distribute the heat.
vinegar.
Having distinguished the difference between power and energy, I pose the question: what kind of power can this new approach yield? Is it practically useful or just theoretically amusing? If generating 288% more energy takes 288% longer to accomplish, you haven't really made any progress.
With oil @ $100/bbl, you better get used to it. And there's nothing wrong with all the work going on for oil alternatives. Something viable may come out of it, and we'll all be better off, well, except for the nutjobs in the ME. They can drink their oil.
So let them explore, and study and come up with news things. It's the American way.
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