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Driving on Starch
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."
I want my car to burn hay!
I have one that burns rice.
God spoke to me.
Wouldn't that be a lot of starch? I mean, wouldn't we then have a shortage of it? I know it's more renewable than gas, but could they even produce enough? They're having a hard enough time with 10% corn for gas. 12 gallons of starch is like, 110 or so bags of starch at the store...
The abbreviations are: PPP, pentose phosphate pathway; G1P, glucose-1-phosphate; G6P, glucose-6-phosphate; 6PG, 6-phosphogluconate; Ru5P, ribulose-5-phosphate; and Pi, inorganic phosphate. The enzymes are: #1, glucan phosphorylase; #2, phosphoglucomutase; #3, G-6-P dehydrogenase; #4, 6-phosphogluconate dehydrogenase, #5 Phosphoribose isomerase; #6, Ribulose 5-phosphate epimerase; #7, Transaldolase; #8, Transketolase, #9, Triose phosphate isomerase; #10, Aldolase, #11, Phosphoglucose isomerase: #12, Fructose-1, 6-bisphosphatase; and #13, Hydrogenase.
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?
Sigs are too short to say anything truly profound so read the above post instead.
Unfortunately, this would be far from commercialization. I can forsee two problems.
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 consequent enzyme degradation could accelerate this. Cost again, to replenish the enzymes. Freezing and thawing in the winter might be very bad for the enzymes as well.
I think that this process is only viable on a factory scale, where skilled people can manage it under controlled conditions.
Well, what need to do is bring back external combustion engines. Then we can simply burn anything: Garden waste, wood, coal, anything that will burn. There is enough coal on this planet to fire up steam engines for thousands of years...
Excuse me, but please get off my Pennisetum Clandestinum, eh!
Now that oil is getting near to being all used the big plan is to use food crops to run you cars? Brilliant, what can go wrong?
You're right, it is not a power source. Nothing is a power source if we were to take it to a certain degree, oil based products got their energy from the sun, so does ethanol, and this new system using starch.(the sun gets its energy from the fusion, so I guess you could say that is a power source, but that gets its power from the mass, which gets its power from... well... magic!)
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 instead use plants (corn/sugar for ethanol, or long dead plants for oil) that changes it into chemical energy that we change into a different chemical energy that is then used for kinetic/thermal energy to drive our cars, which then goes entirely to thermal in the form of friction.
Enough with being pedantic and onto the being practical.
Oil is a power source in the sense that it is readily available stored energy. The difference between it and hydrogen is that hydrogen manufactured through electrolysis is manufactured at a 1:1 ratio of energy put in verses energy removed (under perfect conditions). This starch process allows hydrogen to be produced at a rate much closer to a perfect 0:1 (from our point of view, yes I know energy cannot be created) which is similar to oil.
The question now is, are there enough of these enzymes to go around? Does processing the starch via enzymes leave a byproduct which ends up in our cars? will people be willing to modify their cars to run on hydrogen (a fairly simple process, but try convincing someone of that)? will there be enough starch to go around? In other words, yes it works out chemically, but does it work out practically?
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 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.
I was wondering who actually made that inane grocery store comment, only to find out it was Roland P. No fucking surprise there! What a retard.
you are correct that you put more energy into a system in this case hydrogen production than you get out but hydrogen is meant to be an energy carrier not a true energy source. it is useful when your battery technology relies on crummy Ni/Cd or lead acid technology. it's useful when you can make more usable power from gasoline once it has been converted into hydrogen and carbon dioxide. it isnt the least bit pathetic as you suggest.
Sigs are too short to say anything truly profound so read the above post instead.
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...
Now, I know this probably will never get seen by anyone, but none of the posts so far were appropriate to reply to.
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.
The only infinite resource we have is "human stupidity". When we figure out how to split water molecules using stupidity we'll have the problem licked fer sure.
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.
No sig today...
The grocery stores allow you to get around the bootstrapping problem. Otherwise no one would buy the cars until infrastructure was in place and no one would build the infrastructure until there were cars to buy the fuel.
This will cause world-wide ooblick shortages! Won't someone think of the Children?
-- My Sig is a P228.
I think you're totally missing the point here. The source of the starch will be plant material, which will be the result of photosynthesis. This means that the production process will take out of the atmosphere exactly as much CO2 as will be released when the starch is split up again.
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.
If intelligent life is too complex to evolve on its own, who designed God?
Diesel engines are available now, get *way* better mileage then gasoline engines, are absolutely prefect for SUV-sized vehicles whose owners are convinced they might need to tow something or go off-road, and we know how to make it with almost zero-sum CO2 emissions from human waste.
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?
No sig today...