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Ethanol to Hydrogen Reactor Developed
guacamolefoo writes "CNN reports that researchers at the University of Minnesota have developed a small (2 ft. high) hydrogen reactor that turns ethanol into hydrogen and then uses a fuel cell to turn the hydrogen into electricity. It notably does not use fossil fuels in the process. I knew that liquor would save us all some day."
One item of interest is that this new technique converts ethanol to hydrogen at a 60% efficiency rate, compared to the 20% efficiency rate with current technology.
The IOP web site here claims that ethanol to electricity is 3x more efficient than ethanol for powering vehicle engines.
Ever noticed how most foods and drinks are sweetened with "high fructose corn syrup", rather than the simpler "sugar", and thought it was a bit odd? I'd always just assumed that it was to disguise the ingredient, but that seemed pointless given the nutritional listing of sugar content. Apparently the resolution is that the US government mandates a price for sugar which is about twice the global one. It does not mandate such a price for corn syrup, so corn syrup is cheaper. The major manufacturer of corn syrup (Archer Daniels Midland) "donates" generously to both parties to ensure the continuation of this policy.
(ADM also runs a mammoth ethanol boondoggle based on government subsidies. Every dollar of profits earned by their corn sweetener operation costs consumers ~10$, every dollar earned by their ethanol operation costs taxpayers ~$30.) (ADM also runs a mammoth ethanol boondoggle based on government subsidies. Every dollar of profits earned by their corn sweetener operation costs consumers ~10$, every dollar earned by their ethanol operation costs taxpayers ~$30.)
I call bullshit.
It's true that energy is required to make ethanol, but the most of that energy is bioenergy from the yeast, converting the starch to ethanol + C02. The starch must be heated before it can be converted (gelatinized), and there is some energy required for that but typically done simply from the heat of crushing the corn.
The bulk would be the distilling process, but you could EASILY create a solar distillery or gelatinizing process, too, which is where the bulk of any added energy comes from.
Point is, you can be as inefficient as you like and claim that it's some corn cartel. But I'm not pulling out my tinfoil hat just yet.
As an aside, it's fairly trivial to get a BATF license to distill for fuel.
But there are two considerations to make here that are not part of the above statement:
But the real trick is reducing the costs of processing cellulose to ethanol to make it competitive with processing glucose from corn (which is more easily broken down) into ethanol. This is trivial when you eliminate all the subsidies, it's just a bit harder when you consider the heavy corn ethanol subsidies. However, companies like Iogen have been producing much more efficient techniques such as enzymatic hydrolysis for breaking down cellulose into an easily fermentable form - which they goes into the yeast fermentation process. The technology is already being deployed at modest scale factories.
So the answer is that yes, yeast do the fermentation. And to make fossil fuel-free, net energy positive ethanol, you just add some weak acid or strong enzymes to the mix earlier on to make sugars that are more easily fermented. As for carbon emissions (as CO2 or otherwise), which you mention, ethanol from cellulose "consumes" as much carbon in the growing plants as it releases when combusted, and in that sense it is both renewable and net-carbon-neutral to the environment. So does ethanol from corn, though the fact that the overall energy production is negative in that case means that the energy deficit has to be made up, generally by burning fossil fuels to generate energy for growing and havesting corn.
Which brings us back to many people complaining here on Slashdot that ethanol is bad for the environment. They just don't understand that ethanol != corn ethanol.
Growing all that corn also takes a Lot of Water. more water than rain.
I grow corn in wisconsin and am very surprised to learn that it takes more water than rain. We, for reasons of topology, don't irrigate and our corn and still grow 125-150 bushel corn.
In short, the parent should be modded -1 overgeneralized.
Using power from our very own stellar fusion reactor located at a convenient approximate 18 light minutes, is much cleaner.
That's 8 light minutes, and there are no solar panels yet that are efficient enough to drive a car, much less a tractor. Have you taken a look at how many watts it takes just to get one horsepower? You'd need a small nuclear reactor to produce enough watts to get the 450 horsepower of a tractor! (A 335 Kilowatt reactor to be exact.) Not to mention the number of batteries it would take to keep a tractor running at night.
Solar power is a niche market. It has its uses, but general power generation is not one of them.
Javascript + Nintendo DSi = DSiCade
If ethanol is actually to play an increasing role in the energy needs of the first world (or the US specifically), it will not come from corn, it will be a result of the refining of sugar cane in Latin & South America & the Caribbean. Sugar cane has a much higher energy level and is much easier to convert to ethanol.
Quick quiz: which nation is the largest producer of ethanol, and what is its feedstock?
And as long as we are injecting facts into this discussion (yes, I'm new here...), while corn production does require lots of water, less than a third of US corn production is irrigated.
And finally, as for all of the "Does producing ethanol require more energy than it uses" discussion, the real question is whether ethanol is an efficient mechanism to capture solar energy and store it in chemical form. The evidence is mixed. The professor at Cornell who is frequently cited is David Pimentel, an entymologist. According to those who specialize in energy, the conclusion for corn-based ethanol is much, much more nuanced. Newer processing plants (those built in the last 3 years) fed by farmers using appropriate nitrogen application techniques are energy-positive. But there are many legacy plants (as well as legacy farmers). Again, in the long-term, the cost of conversion & transport from warmer climes is actually more relevant, though.
And yes, by the way, IAAAE (I am an agricultural economist). In fact, IAAGE (I am a grains economist for a Big Ten University)
Answer: Brazil, sugar cane.
I assume you mean 125-150 bushels per acre?
;-)
Yes. In the vernacular "100 bushel corn" is 100 per acre.
Not being of an agricultural bent, I don't know if this is a realistic yield or not.
For my area it is a good yield. I suppose some people might go as low as 80-100, but they aren't making anything at that. Really pro farmers on really good soil might go 175 or even 200 if the weather works with them.
Is this measured on the cob or off?
Off.
For each bushel, how much waste (stalks & cobs, etc) is produced?
A ton. Perhaps literally.
Would burning 150 bushels' worth of (sun-dried) waste produce enough heat to distil 150 bushels' worth of mash?
Dunno. But it may not be the right question anyway. It may well be better to cut the corn like you would for silage and use the entire plant for mash, then use the increased energy production to heat to mix. I'm just speculating though, I haven't fact one to back up that guess.
How much gas does your tractor take to plant & harvest a 1 acre cornfield?
None. We use deisel.
In truth that answer depends on how many times you have to pass over the field. A no-till planter is going to cost you half a gallon an acre and combining is about a gallon and a half.
However, you will typically double or triple that without getting into nutty scenarios. If you are doing zone building that's going to be another gallon and a half, fertilizing can vary between a tenth and a half. If you chop for silage (as I suggest above) you burn three and a quarter per acre right there.
So, the amount varies widly depending on what you're doing.