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Switchgrass Makes Better Ethanol Than Corn
statemachine writes to mention that the USDA and farmers took part in a 5-year study of switchgrass, a grass native to North America. The study found that switchgrass ethanol can deliver around 540 percent of the energy used to produce it, as opposed to corn ethanol which can only yield around 24 percent. "But even a native prairie grass needs a helping hand from scientists and farmers to deliver the yields necessary to help ethanol become a viable alternative to petroleum-derived gasoline, Vogel argues. 'To really maximize their yield potential, you need to provide nitrogen fertilization,' he says, as well as improved breeding techniques and genetic strains. 'Low input systems are just not going to be able to get the energy per acre needed to provide feed, fuel and fiber.'"
It's true that corn is a pretty poor feedstock for ethanol generation. But I think most people (farmer subsidy lovers) think that ethanol has come into focus because of its potential as a fuel *replacement* for gasoline.
Let me remind you why we have a demand for ethanol in the first place: a replacement for MTBE, a gasoline anti-knock additive (letting the engine run at higher compression ratios, and thus more efficiently) which was found to be leeching into groundwater and concentrating. MTBE is being phased out, and ethanol is a replacement chemical. Whether or not ethanol will be used as an energy source is irrelevant. It's critical today as a fuel additive for gasoline. Beyond that, it's a pretty inefficient energy carrier. Switchgrass may do better, but we're not there yet.
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When you replace oil with ethanol, you stop using carbon that was fixed a long time in the past (and thus did not contribute to present levels of co2), and instead use carbon that was fixed in the last growing cycle. The net co2 added to the atmosphere in a year is zero, because the corn/switchgrass has to fix the co2 before you can later release it in the burn cycle.
"Who is the Journal of Quantum Physics going to believe?" --Stephen Hawking
except that many hops farmers have switched from farming hops on their premium farm land, to farming inefficient corn, thus driving up the price of beer.
it's hard for something to be "free, as in beer" when a bottle of beer is very expensive to make due to a hops shortage.
it never makes sense to burn our food.
This has been circulating around the intarwebs for a few days now, so it spurred me to do some background reading already.
Corn has higher amounts of the simpler sugars that bacteria need to work on to produce the ethanol. Switchgrass and other cellulosic feedstocks, which are largely equivalent in feasbility in general terms, have those sugars bound up in...you guessed it...cellulose. Because of this it requires much more processing prior to fermentation. There are several ways to do this with varying costs and efficiencies, but at the very least is technically viable.
However, this pre-processing and the fact that large-scale cellulosic ethanol production is a new technology means the initial costs are higher. According to Wikipedia (with original sources referenced), corn ethanol plants cost about $1-3 per gallon of annual capacity to construct. The first round of large scale cellulosic ethanol plants now under construction are billed about $7 per gallon of annual capacity. Production costs are expected to run about $2.25 per gallon initially, or about $125 per barrel of oil energy equivalent.
However, as the method is proven, that cost is expected to come down. About $350 million of cost is also being funded by the federal government under the new energy plan. Also, the cost of the feedstock for cellulosic ethanol production is much lower, as it can use switchgrass as mentioned in the summary, corn stover, wood chips, or just about anything else containing plant matter, where as the corn method requires corn (duh), and thus competes with food production.
Of course, the article makes the energy-return benefit over corn ethanol obvious. Elsewhere it has been estimated that cellulosic ethanol production could account for 30% of our transportation energy needs in a couple decades. Obviously far short of weaning us off foreign oil, but a start nonetheless. However, an added benefit of using grasses like switchgrass is the fields don't have to be replanted every year, reducing soil depletion and erosion.
Hemp seed is actually really healthy and contains good amounts of all essential amino acids (and so is high in protein). It provides some iron, good amounts of manganese and magnesium, and is also a good source of omega-3 and -6 fatty acids. Hemp seeds are good for salad toppings, baking, etc (think multi-grain bread). Hemp oil is also highly nutritious and can be used as other vegetable oils are.
It's a shame that prohibition drives the seed prices through the roof.
This means that corn gets you negative amounts of fuel (you'll use more farming it than you'll get out of farming it), while switchgrass gets you fuel.
The only reason corn has been chosen as the main crop for getting ethanol in the US is because of the strong cron lobby. It really isn't a feasible energy *source*, since it uses more energy than it produces.
I get a check every year that disagrees with you.
They may not be sugar-lobby powerful, but they still manage to farm the government well enough.
omnia tua castra sunt nobis
You must have a rather slippery seat.
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IANA Biochemist, but it seems to me like switchgrass should take a back seat to Jatropha? Jatropha would seem to ge the nod because not only does it grow in poor soil conditions, it already has a high oil content. Nor do we have to worry about any GE going on, as it isn't an edible crop. (Although its toxicity may pose other problems.)
You stereotypers are all the same...
For all the people who are complaining about the summary/headline, please know that it is hard to fit all of the math in the headline. Please read the article for that. ScuttleMonkey redid my headline (although slightly more correct, he made it more vague).
For those who say there aren't refineries, ScuttleMonkey took out my quotes and put different ones in. I said the DoE is partially funding new refineries, the first of which will come online in Georgia -- also in the fine article.
Although I credit and thank ScuttleMonkey for greenlighting my submission whereas it was flatly ignored yesterday when I submitted it, please complain about his editing, and not my original content, if you feel the summary was vague or had omissions. You can compare both if you read the firehose submission (complain to me if you don't like that one).
Interesting. I hadn't heard of this before.
It seems that BP is thinking along the same lines too.
BP's Bet on Butanol
BioButanol: a better biofuel (fact sheet)
Jatropha will not grow in the bulk of the US landmass, it is a subtropical plant and can only tolerate a few light frosts. I looked into it for a fuel crop here and even this being Georgia, we are too far north.
I agree with the other poster, either switchgrass or industrial hemp are better targets for exploitation for biofuels using marginal land in most areas of the US.
1. Growing corn gets you food OR fuel, not both.
2. Corn is subsidized, thus its true costs are hidden from us.
3. Corn must be re-planted every year from seeds. Switchgrass is a perennial whose 'produce' can be harvested from the same plant each year.
Ironically, the word ironically is often used incorrectly.
Hence the term "Carbon Neutral".
After the fuel is burnt, you end up with the same amount of CO2 in the atmosphere. OTOH, with petrofuels, you end up with more CO2 than you started with.
At the moment, yes. But there's little reason to believe that will always be the case, especially with the advances in wind, solar and tidal power, coupled with increased intrest in Nuclear power.
The excess material was created by removing CO2 from the atmosphere. So burning it is still carbon-neutral.
I'm not sure what the heck you're talking about here. The Energy Balance tab has nothing to do with carbon. It's comparing the energy of the final fuel to the energy required to make it. Energy is energy in that graphic, whether the energy comes from oil or from a nuclear reactor.
Now, if you're talking about the CO2 tab, that one actually does deal with carbon. However, there's several sources of ethanol, so it's not clear what you're referring to. The worst being corn at 22% reduction, and best being celluose at 91%Sugar beets have a high sugar content(therefore can make more EtOH), and can grow in fairly cold, adverse environments. Grows quite well in North America. Corn is being used because of the lobbying effort of Archer-Daniel Midland, a world leader in processing corn, wheat, soybeans. Corn is a lousy product to make ethanol.
Ethanol yield/per acre for sugar beets is about 2x times that of corn, and about 25% higher than sugar cane.
Sugar cane is more efficiently made into ethanol yielding 8 times as much energy as required to make it, sugar beets only about twice. Corn is nearly an even output.
..........FULL STOP.
I would be in favor of more algae research and deployment, but not necessarily in the oceans but in controlled pools/tanks in the desert, in combination with some some solar and geo thermal and perhaps very large greenhouses. And mostly because they will most likely go for genetically modified algae and I wouldn't want to chance such a crop going wild with unintended consequences. I also think they could control it better in pools or tanks than in the wide open ocean. I've worked on the ocean before, it ain't always a flat millpond...
;)
I think the energy question will be answered with an "all of the above" solution, I am not seeing any single one solution fitting all circumstances everywhere. although back to the jatropha, mexico's oil fields are now in decline, it probably wouldn't hurt them a bit to see if they could start to squeeze a few million acres of the plant in there before it goes into fast decline....
Personally I am trying to eventually go full personal production for the fuels I need/use, to decentralize production (doing my bit to be part of the solution rather than just part of the problem), and also pure self interest-keep my wallet stuffed more than "theirs". I am not real far along yet, just wood as primary heating fuel, perpetual supply and carbon neutral, some solar PV,a greenhouse for year round food production (helps drop shipping demand/fuel use/pollution from imported foods, plus it is just better to make your own food onsite, IMO, tastier!), but am working towards liquid biodiesel next, that's why I happened to know about the jatropha, I had looked into it and had to abandon the idea. Most likely we will be looking at using waste chicken litter for a feedstock source, as we have that in rather large abundance
The sugar price supports paradoxically play a big role in hurting Hawaii's sugar industry. The price floor means that the minimum price for sugar from Florida, Louisiana, and Texas is the same as that for Hawaii, so producers in those states make just as much money for their sugar, but have much lower costs for labor and transportation. The supports are also a significant incentive to producers in those other states to produce as much as they can, which negates Hawaii's dramatic per-acre productivity advantage.
"FDA staff reviewers expressed concern about the number of patients who were left out of the study because they died."
>Growing corn gets you fuel, OR food. Farms aren't going to use the
>same crop to produce fuel and food-- they'll produce one or the other.
I am a farmer, and I'm right in the middle of this. I'm hoping to profit nicely from ethanol demand.
The corn I grow is a commodity. I really don't care if the buyer uses it for food or ethanol production. I store it in my grain bins and sell it when the price is right.
Corn is a nicely flexible commodity. I like it.
>Also, should your fuel sources be competing
>with your food sources?
It doesn't really matter. We farmers can grow extreme amounts of corn without much effort. We're so good at it, we've had to hold ourselves back on production for decades.
Switchgrass, on the other hand, doesn't have much use other than (potentially) as fuel. I sure don't want to eat it. I could grow it quite easily if the market demands it, but I'd need to tool up with different equipment and farming techniques. It's a real hassle to bale and store hay...I don't expect switchgrass would be much different. The root system created by switchgrass would make a field hell to get back to where I could plant corn again if it were needed for food.
I can't think of any marginal land where growing switchgrass would make much sense, either. If it's not growing corn, I've got better uses for it, even if it is only grazing land for livestock.
>Growing hemp gets you fuel, food, and fiber.
Don't get me started on that damn ditchweed. It's rough on equipment. My family tried it years ago when it was needed during the wars. We're still trying to reclaim land lost to it. You can't eat it, and you sure as hell can't smoke it. About the only decent thing I can say about it is it's good for erosion control. That's why it's called ditchweed.
>Hemp doesn't produce a sizable amount of food.
Damn straight.
Keep in mind that ethanol doesn't require the nitrogenous components, so most of the "waste" can be put back on the fields.
Yes, there will be loss, but it's not anywhere near as bad as some make out. Any decent organic farmer can lecture for hours on the wonders of compost, and as long as the farmers are careful about irrigation runoff, it isn't too bad.