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Friday, May 25, 2007 Running Cars on Hydrogen Made from StarchA new way to make hydrogen from corn or potatoes could make fuel-cell vehicles more practical. By Kevin Bullis
Using a stew of enzymes culled from several organisms, researchers have developed a way to convert starch, available from numerous sources including corn and potatoes, into hydrogen gas at low temperatures and pressures. The method produces three times more hydrogen than an older enzymatic method does, suggesting that it might be practical to use such enzymes to produce hydrogen for fuel-cell vehicles. While fuel-cell vehicles are appealing because they emit no pollutants, it's been a challenge to find clean and affordable ways to produce, transport, and store hydrogen to fuel them. Most commonly, hydrogen is extracted from fossil fuels. Making hydrogen by electrolyzing water is energy intensive and can be expensive. The new system improves on other experimental methods for creating hydrogen from biomass by using low temperatures, making it potentially more convenient and energy efficient. The researchers--from Virginia Tech, in Blacksburg, VA; Oak Ridge National Laboratory; and the University of Georgia, in Athens--combined 13 commercially available enzymes isolated from yeast, bacteria, spinach, and rabbit muscle. The work is available online in PLoS ONE, a journal published by the Public Library of Science. The hydrogen comes from two sources: the starch and the water used to oxidize the starch. The enzymes facilitate chemical reactions in which the water and starch can be completely converted into hydrogen and carbon dioxide, says Y. Percival Zhang, professor of biological systems at Virginia Tech. (The carbon dioxide released is offset by the carbon dioxide captured by plants that provide the starch.) The new system produces a higher yield of hydrogen than previous experimental systems that used enzymes for converting sugars into hydrogen. But while the yield of hydrogen is high, so far the rates at which the gas is produced are extremely low. That's in part because the researchers used off-the-shelf enzymes and have not optimized the system, Zhang says. The scientists' next project will include analyzing each stage of the process in detail to find the rate-limiting steps. For example, one of the enzymes may be producing a by-product that slows down later steps, says Michael Adams, professor of biochemistry and molecular biology at the University of Georgia. The researchers would then look for other enzymes, or modify current ones, to minimize the by-product. They will also look for enzymes that can operate at higher temperatures. "If you increase the temperature by 10 degrees, most times you can increase the reaction rate twofold," Zhang says. One of the first applications of the system, Zhang says, could be generating hydrogen for fuel cells in portable electronics. The starch could be a safer way of storing energy than using methanol, a current leading option for such small fuel-cell systems. He estimates that it will take about six to eight years to improve the rates enough for such applications. Eventually, he hopes to use his process to solve one of the biggest current problems with hydrogen fuel-cell vehicles: fitting enough hydrogen on board to compete with gasoline-powered vehicles. |
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Making Fuel from Leftovers
11/26/2007
Comments
thmlco on 05/25/2007 at 12:41 PM
4
What we need instead is to figure out how to make hydrogen from something common that's not part of the food chain.
So how about making hydrogen from the common everyday grass? We already have a major industry devoted to growing rich green lawns, cutting then, and then taking the results away for disposal.
Why not put it to use?
Kinch on 05/25/2007 at 1:28 PM
2
deirdrebeth on 05/25/2007 at 2:59 PM
25
http://www.mepartnership.org/mep_whatsnew.asp?new_id=2146
thmlco on 05/26/2007 at 4:53 AM
4
georgesoars on 05/26/2007 at 1:54 PM
1
Figure this, the article states that making hydrogen from starch a solid thing will take about 6-8 years of research. Well after that you still needs resources, biomass, natural gas, water etc. Plus all the energy it will take to process the biomass and the enzymes to make the whole thing work.
I suggest something different, how about we focus our efforts (and money) in making clean renewable electricity (that will pay for itself by leaps and bounds) and in researching better battery technologies for homes and autos (aluminum, li-ion etc). In the long run this research will probably cost less than hydrogen, the distribution system is already in place and by going clean it reduces our carbon footprint.
We have to get away from burning fuels. This link is very telling of how burning fuels is affecting the global atmosphere, http://airs.jpl.nasa.gov/
frogonroad on 05/27/2007 at 5:22 PM
1
Since we are intellegent creative and somewhat responsible beings capable of figuring out all kinds of ways to make our lives better and more profitable, should we not embrace the technologies we NOW have to produce a clean fuel that has no harmful effects on our health and environment?
Harness the massive amounts of energy the sun provides free everyday. Turn it into electricity. Use this electricity directly to power our daily needs. Store the excess electricity in the most lightweight and energy intense battery in the universe, hydrogen, use the hydrogen to power our toys and get on with the business of creating a better world to explore and enjoy.
What?
killian on 05/28/2007 at 9:48 AM
54
If the H2 is produced without first producing electricity, then it should be compared to the efficiency of producing electricity. For example, Tilman's Carbon-Negative Low-Intensity High-Diversity Biomass paper last year estimated that (in the supplementary materials) that producing electricity was better than producing ethanol. So why use 2,000,000 mi^2 of prairie when 1,000,000 mi^2 will do?
killian on 05/28/2007 at 9:37 AM
54
On the other side, all the technology to make great EVs (both battery electric vehicles and plug-in hybrid electric vehicles) already exists. Both Altairnano and A123 systems have batteries with all of the necessary attributes (e.g. long lifetimes, unlike laptop batteries and fast recharge times). The one problem is cost, but since both companies are young and ramping up, I think cost will fall as it has on 18650 LiIon cells (found in laptops).
Getting automakers to build PHEVs however remains tricky. They prefer to talk about 2020 FCVs rather than 2010 PHEVs.
rden on 08/27/2007 at 11:18 AM
5
killian on 05/28/2007 at 9:27 AM
54
Silacon on 05/25/2007 at 3:09 PM
33
Chad on 05/25/2007 at 11:09 PM
6
killian on 05/28/2007 at 11:29 AM
54
dinmu on 06/01/2007 at 7:44 AM
2
For hydrogen to work, it should create a energy and emission balance.
jrandolph on 06/27/2007 at 12:46 PM
1
However, I am a fat person who is not lazy, nor eats too much. In fact other than coffee in the morning...I typically only have one meal (dinner) a day, as I typically work 50-85 hours per week.
I thought your attitude towards larger people had a connection with Hitler as you came across as a cold elitist. Perhaps you should examine your heart to see if bloods is still flowing through it. We could extract the FAT from your HEAD!
johnnizanni on 05/25/2007 at 3:10 PM
7
dmtk on 05/28/2007 at 1:37 AM
3
If we are going to use that land for transportation isnt it better if we cover it all with PV instead of biomass production?
killian on 05/28/2007 at 9:52 AM
54
stuka2 on 05/28/2007 at 3:02 PM
1
kearns on 05/29/2007 at 4:39 PM
23
socalrws on 06/26/2007 at 3:05 PM
1
See their Video for a complete explanation.
http://www.nrel.gov/hydrogen/proj_wind_hydrogen_video.html
More info here-
http://www.nrel.gov/hydrogen/pdfs/utility_hug_briefing.pdf
A Means to the Hydrogen Age: The U.S. Power Industry (PDF 1.86 MB)
http://www.nrel.gov/hydrogen/pdfs/doe_hug_briefing.pdf
DOE Perspectives on the Hydrogen Utility Group (PDF 772 KB)
Colby_W on 06/27/2007 at 2:49 AM
1
JonD on 08/08/2007 at 10:35 AM
4
Wake up.... I have never seen so much Stupidity in educated circles.
rden on 08/27/2007 at 11:17 AM
5
hano on 05/31/2008 at 5:44 PM
3