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Driving on Starch
Posted by
Zonk
on Sun May 27, 2007 12:16 AM
from the oh-mr.-fusion-you're-so-efficient dept.
from the oh-mr.-fusion-you're-so-efficient dept.
Roland Piquepaille writes "Using sugar contained in corn or potatoes to build hydrogen-powered fuel cells has already been done. But now, a team of U.S. researchers has developed a new sugar-to-hydrogen technology. Why not put the starch inside the tank of your car? With the help of 13 specific enzymes, 'a car with an approximately 12-gallon tank could hold 27 kilograms (kg) of starch, which is the equivalent of 4 kg of hydrogen. The range would be more than 300 miles, estimates one of the researchers. One kg of starch will produce the same energy output as 1.12 kg (0.38 gallons) of gasoline.' The beauty behind this idea is that no special infrastructure would be needed. Starch could be distributed by your local grocery store."
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Hay (Score:2)
Re:Hay (Score:5, Funny)
I have one that burns rice.
Parent
Hey! (Score:2)
Re: (Score:2)
Done. [wikipedia.org]
Pop and junk food or ... human fat ! (Score:3, Interesting)
That should curb obesity in this country. But then we have all this energy already stored as fat on our bodies. Well, we'll just have to design a car that runs on human fat. Just cut that love handle, toss it in a gas/fat tank and there you go, drive to the store and buy more Twinkies to put that lost chunk of fat back and keep going...
The only infinite resource is "human stupidity" (Score:5, Funny)
I'm sure a breakthrough can't be too far away, most modern SUVs are already running on 50% stupidity, we just need to improve the yield.
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Re:Pop and junk food or ... human fat ! (Score:4, Funny)
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Question (Score:5, Interesting)
Re:Question (Score:5, Interesting)
Yeah, someone isnt thinking energy alternatives through again. 1,000 people a day probably visit my grocery store. How are they going to pull 13 gallons of starch each? Where will by store put 13,000 gallons a day. In the cereal aisle?
You will need a gas station like place to move this much product.
Secondly, where is this stuff coming from? etc etc etc
Parent
Re: (Score:2, Informative)
From TFA:
So all of these people drive 300 miles a day?
I see your point regarding the s
Re:Question (Score:5, Insightful)
The question is - how many gas stations are there and how many grocery stores are there. Then find out how many people go to the gas stations and fill up every day - then look at what kind of traffic that means for the grocery store. I'm willing to bet that the gp is right in that the number is large.
What do people normally buy at the grocery store in 12 or 13 gallon quantities right now?
And when you say do those people drive 300 miles a day - that's not accurate either. I don't think too many people go to the grocery store every day. I go 1 or 2 times a week. We fill our car about once a week. So in my case, the number of trips to a gas station and grocery store are similar now. But when I buy gas - there are 3 or 4 gas stations near where I live - and one grocery store.
The numbers are all guesses, but like I said, the intent of the gp is probably pretty much right. The current distribution system for groceries (in the US anyway) is not sufficient to handle also providing fuel needs for the public on top of the food.
Parent
Re:Question (Score:5, Insightful)
Perhaps you don't realize how little that actually matters. It's one thing to build an infrastructure that's inherently incompatible with existing infrastructure. It's another thing entirely to extend and amplify an existing infrastructure.
Let's take your "tank a week" scenario. It's roughly on par with Gasoline per unit of weight (Kg) so we're talking about a 10-gallon tank in your average 4-5 seater car. Gasoline weighs about 6 pounds per gallon, so that's about 60 lbs per week to meet a not-atypical situation. I buy a 50-lb bag of dogfood every other week thanks to my large golden retriever.
What's important is the cost of entry - not the total cost. It doesn't really matter what the total cost is, as long as the initial cost can be made up in profits quickly. Once the enterprise is profitable, it doesn't really matter much what the costs are, since the enterprise is, by definition, profitable and thus has the means to grow.
Here, we're talking about starch as merely an additional product that I can buy, along with the 50-lb bag of dog food. The initial cost of entry to sell starch to early adopters is so low as to be inconsequential.
Compare/contrast that with typical hydrogen scenarios, with expensive retrofits of existing fuel stations, special tanks, special dispensation stations, etc. See the difference?
Yes, your local grocery mart probably isn't going to provide enough fuel for everybody in town next to the dog food aisle. But they can start there, and then as the profits grow, roll out more specialized stations as the demand justifies it. See the difference?
Parent
Re:Question (Score:5, Insightful)
My one fear is the process that releases the hydrogen gas might not be as fast as we can demand it from a red light and once the process is started can we shut off the car and not have it wasted. If there is a storage tank that meters in hydrogen to keep a constant reserve available for quick use and a way to store the excess after pulling into the driveway, then it might be ok. This all adds weight and complexity not discussed in the article. They make it sound like all you'd have to have is a tank full of starch. Where are the reacting agents stored and how do we refill those? What waste products to the chemical reactions give off and are they containable or toxic? What about the liquids that would be needed to move the starch and reactive agents around the system, or are we dealing with pellets of starch and have to have a hopper system like in pellet stoves? I think that these are the concerns that people should be asking rather than will Walmart have enough starch to run my new starch SUV. That's jumping the gun a bit in my opinion. Or in slashdot pun style, putting the cart before the horse.
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Re: (Score:3, Informative)
Re: (Score:3, Interesting)
One other thing to consider is the viability of having this enzyme process run in the tank of a vehicle. Even the most robust kinds of these reactions require a relatively stable environment. It might be possible to do this in a reactor in one's garage, but not in a vehicle that gets parked in the hot sun or below zero winter temperatures vehicles encounter. Additionally, is this process throttleable? It doesn't seem so. In other works, w
Re:Question (Score:4, Funny)
Beer! 24oz cans, 10/$10 at Krogers!
Parent
Re: (Score:2, Interesting)
Why, in a big tank [google.com] of course. Doesn't your local grocery store have one of these in the cereal aisle?
Not that you'd have each customer filling their gas tank, from empty, every day. But sure, figure a thousand tanks per week - that's only 6 an hour for a 24-hr 'starch st
Re: (Score:2)
The fuel system is going to need a complete redesign, so there's nothing to stop them from putting a funnel with a vibrating channel to the tank to keep it moving. Just dump it in.
Re:Question (Score:5, Insightful)
I think you're a bit unfair here. What I think he means to say is "The starch could be distributed by your local grocery store," or "It could be starch distributed by your local grocery store." The point is not that all vehicle fuel will henceforth be bought at grocery stores, but that the substance is already widely available, and wouldn't need a new, special infrastructure the way mass distribution of hydrogen would.
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"Diesel", the word you're looking for is "Diesel" (Score:3, Informative)
Most people wouldn't even notice the difference between gas/diesel SUVs unless you told them.
So:
a) Which part of that isn't "win"?
b) Which part doesn't make "starch" or "ethanol" look like a silly idea?
bio-diesel may be affecting cooking oil prices... (Score:2)
Re:bio-diesel may be affecting cooking oil prices. (Score:2)
http://news.com.com/Biodiesel+to+drive+up+the+pri c e+of+cooking+oil/2100-11389_3-6114425.html [com.com]
And here is the tinyurl for it:
http://tinyurl.com/esxef [tinyurl.com]
That Michael Kanellos article in Cnet was dated 2006/9/12 and was entitled, "Biodiesel to drive up the price of cooking oil".
Re: (Score:2)
Re: (Score:2)
Well, our synthetic methods for capturing sunlight are inefficient, plants are better at it. So, plant-originated ethanol/hydrogren/etc is a compelling solution. And it turns out that high-energy plants.... tend to be food sources, imagine that.
Has anyone done long-term economic forecasts of the effect of using the same source for both food and fuel? While it would drive up prices in the short term (before supply ramped up to meet demand), there's some chance that the larger volume would result in low
Re: (Score:3, Funny)
You'd finally have a use for the mega-sized box of starch at Costco...you'd need only 11 of those. :-)
Doesn't really discuss costs. (Score:2)
As far as a storage mechanism goes it sounds like it might have advantages but how complicated is the process to break it down for hydrogen? How much does it cost to make the enzymes and what not needed to break it down as well?
Overall
from the article (Score:5, Informative)
it looks like they built it like this: starch=>glucose [amylase]=>glycolysis=>pyruvate decarboxylation=>TCA cycle and finally liberating the hydrogen from protons and electrons from the TCA. I wonder from this is how they deal with the enzyme's need for cofactors, corrosion, stability of enzymes and side reactions. it looks promising for sure but it looks like they have a lot of work ahead of them. there is also the problem of the starch settling in the tank and thus being unavailable for the reaction unless that is where it happens in that case what about H2 build up? lastly, with the problem of corn shortages being possible for ethanol, what exactly will happen when starch is used instead as it is also taken from food plant sources?
Re:from the article (Score:4, Interesting)
Parent
Wave the magic wand? (Score:2, Insightful)
First would be the effective rate of production of hydrogen. Demand for high hydrogen production rates, as in throw the starch into your tank and get your ass on down the road, would probably demand high levels of these enzymes. Which would mean cost.
Second would be the fact that enzymes are protein-based and therefore have finite lifetimes before catalytic activity is lost totally. Potentially, bacterial contamination and
External combustion engines (Score:4, Interesting)
Re:External combustion engines (Score:5, Insightful)
Parent
Re: (Score:3, Interesting)
Beiging is not burning carbon-neutral fuels. Nor are they filtering emissions. Don't confuse the issue here.
Anyone who automatically things combustion is bad needs to start with themselves first. We burn sugar all day long.
If we can find a way to produce carbon-neutra
Re: (Score:3, Interesting)
That coal/oil burning/swamping CO2 into the atmosphere in what? 2 centuries or so of accumulated solar energy which took maybe millions of years to build up is exactly what the dilemma of global warming causes (some still dispute that it is actually happening or discredit any argument towards it).
Now you want to put all kinds of dirty burning junk into your "converter" to accelerate over a ton of steel and plastic and move
Food (Score:4, Insightful)
Re: (Score:3, Interesting)
Oil production does seem to be slowing in growth, if this chart is any indicator:
http://en.wikipedia.org/wiki/Image:WorldOilProduct ion2002-2006Q2.gif [wikipedia.org]
There are plenty of sources for oil, but it's a question of access, cost to get it and how quickly it can be produced. There is supposedly a lot of oil sand and oil shale, but recovering it can be
Roland the Plogger again (Score:4, Interesting)
It's Roland the Plogger again, wrong as usual.
It's been possible to convert cellulose to ethanol using enzymes for a while now. The problem is that making the enzymes is still too expensive for this to be useful as a fuel process. This Wikipedia article [wikipedia.org] provides some background on that. It's a good idea. If the cost of making the enzymes can be brought down, there's plenty of agricultural waste (straw, bagasse, corn cobs, wood chips) available at low or even negative (it costs money to dispose of it) cost. Venture capital is going into developing cost-effective processes.
But it's not likely to be done in a car's fuel tank. Something more like a brewery scaled up to oil refinery size is more like it.
Re: (Score:3, Informative)
Read the research web site [vt.edu], not the press release or the Roland the Plogger misinterpretation. This research involves several approaches of cracking cellulose from agricultural waste down to something more useful. Starches and cellulose are both glucose chains.
The back end of the process is supposed to be a scheme for getting hydrogen from sugar. Their goal is C5H10O5 + 7 H2O --> 12 H2 + 6 CO2, driven by some synthetic enzymes. But they're vague on how far they've actually progressed in this direct
Nope. (Score:2)
WRONG.
It might be that way for the first person who does it, or the first thousand people. But anything connected to transportation requires special infrastructure. Millions and millions of cars and trucks drive millions of miles per day, and consume millions of gallons of gasoline. Your local grocery store is not set up to handle the business your local two dozen gas statio
Re: (Score:3, Insightful)
Nice, but... (Score:2)
...the only way an alternative fuel will gain wide acceptance, manufacturer support, and wide distribution is if you can...
Re: (Score:2)
confusing figures (Score:2)
super cool idea though, i'm impressed that they can even break even and produce enough energy to move the weight of the starch.
Re: (Score:2)
Very impressive. (Score:5, Informative)
I am actually a bioengineer, and I'm actually working in this field, trying to convert ethanol into hydrogen.
And I can say, this process looks excellent. Finding natural enzymes that do the conversion makes everything enormously easier.
Here's the deal. Ethanol has slightly more energy than straight sugar, because the fermentation adds energy to the system. That added energy is negligible in comparison to the total energy. However, you lose a butt-load of energy because you have to heat the sugar up in order to ferment it, deal with transportation costs for the crops, and if you're using it as an additive (instead of reforming 20-25% ethanol in water directly), distill it to 100%, which uses a ridiculous amount of energy (10 times more to get it from 95-100 than from 20-95). However, the plus side is that ethanol is a pretty high energy density liquid, about 85% that of gasoline, and much higher energy density than compressed hydrogen gas. So, with an ethanol+water mixture, you end up getting 6 H2 out of every one etOH molecule. Pretty durn good. (if you think I'm an idiot because I have more hydrogen coming out than are on an ethanol molecule, look up steam reforming instead of making yourself look like a fool)
However, at the end of the day, it's extremely questionable whether or not ethanol itself is net energy positive, because of all the energy that goes into producing it (even though the liquid itself increases in energy density). Sugar, however, is less refined, and so less energy goes into making it. The idea is this -- if the net energy is negative, then you're still using more fossil fuels than you save. But if sugar is energy positive, then you can use 1kg of sugar to produce 2kg of sugar, and use that to make 4kg of sugar, and so on.
Sure, you have to pay attention to the problems of rising food costs. But starch? Don't worry about it, it'll be more efficient than gasoline, and it'll be more efficient than ethanol. You're talking a 3x fold improvement on efficiency right off the bat because it's a fuel cell instead of an I.C.E. Now, your sugar production has to be net energy positive, so multiply that factor (guess would be around 2-3) times the 3x fold efficiency improvement in the fuel cell and you're using 6-9 times less energy to produce the same amount of work. The economy will figure out the rest -- hell, you can get starch out of all sorts of crop waste way more easily than you can get ethanol out of them.
Re: (Score:3, Insightful)
Ooblick! (Score:3, Funny)
Re:Cue the "hydrogen is not a power source" chorus (Score:3, Informative)
But the real important thing is turning it into a form of energy that we can use. We cannot use the sun's energy directly, we ins
Net versus Gross (Score:2)
I'm not impressived by the "net" ammount of carbon dioxide released by one process, if you're going to compare to the "gross" ammount released by the oil/gasoline process.
Try it with your paycheck, compare the gross income or your paycheck to the net income of a coworkers. Don't they have a word for this type of "accounting", specifically when used in the energy sector? Ah yes, they call it E
Re: (Score:3, Informative)
Re:byproducts much? (Score:4, Insightful)
Ultimately this is a "solar powered" system. The energy what goes into the production of the starch comes from sunlight. It also happens to output the energy in a convenient chemical form which has better energy density that current battery technology.
Parent