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More "Miles Per Acre" From Bioelectricity Than Ethanol
CarnegieScience writes "Scientist calculate that, compared to ethanol used for internal combustion engines, bioelectricity used for battery-powered vehicles would deliver an average of 80% more miles of transportation per acre of crops, while also providing double the greenhouse gas offsets to mitigate climate change."
Large powerplants more efficient than vehicle-sized engines. Video at 10.
Personally, I'd like to see someone address the fact that our growing methods are dependent on petroleum-based fertilizers. How can all those ethanol makers in Iowa produce their corn without Arabian-supplied nitrogen?
Almost as useful as miles per gallon...
Comparing energy production density to Corn-based Ethanol is like stealing candy from a baby. Corn-fueled Ethanol has a tough time doing much better than just burning fossil fuels outright in systemic carbon footprint, and in some studies, is actually WORSE than strictly burning gasoline/oil.
Yes, the average is a net improvement of anywhere from 25% to 70% return on investment, but even then, you have to consider the value of the farmland itself! We'd probably do much better by simply growing wild grass on prime farmland, harvesting it, and burying it, when looking in terms of carbon footprint!
So saying that NNN technology is X% better than bioethanol is like saying that doing X is less painful than scraping off your penile foreskin with a cheese grater.
Truthful, but not very useful. Come back when you have something that actually works. For example, what's the benefit of bio-electricity over Photo-voltaics? Now that the latter technology is down to (or better than) $1/watt, this becomes a very, very tough technology to beat, and actually works better on craptastic, rocky soil off in the desert someplace with 3 inches of rainfall per year.
Meaning, we can get back to using farmland for growing food, and stop with this silly "let's raid the kitchen cupboard to feed our guzzling SUVs!" craze that's been on for the last few years.
I have no problem with your religion until you decide it's reason to deprive others of the truth.
I think it's pretty clear what they are saying: with bioelectricity you get more harvastable energy per acre of planting. Crops take space to grow.
but.... then also see: http://tech.slashdot.org/comments.pl?sid=1225951&cid=27864987
food crops->energy = ill advised
If you cannot keep politics out of your moderation remove yourself from the Mod Lottery.. NOW!
If you thought that ethanol production was an ecological problem, then you should rethink your beliefs. Ethanol from corn is a political gambit, government subsidies for corn/ethinol is just a way to but votes. It is not an economical process, in fact it is one of the worst possible ways to create ethanol, and only succeeds in raising the cost of food.
Who would win this election: Andrew Weiner vs Andrew Weiner's weiner.
Aglae can produce oil instead of ethanol. Oil that can be treated just like light sweet crude at the refinery, with a lot less impurities [so it's easier to refine].
So to not do something stupid like Algae Ethanol and do Algae Oil the biggest advantage is it's a potentially carbon neutral drop in replacement that can be used in existing gasoline and diesel engines.
If you can get efficient storage of electricity (like hopefully EEStor isn't full of it) a pure-eletric system will be better - but at the same time we can cut our greenhouse gas emissions massively by using Algal Oil as a drop in replacement for fossil oil.
Now as gas/diesel demand drops down in about 50 years we can do other things with that algae production infrastructure I'd imagine.
If you cannot keep politics out of your moderation remove yourself from the Mod Lottery.. NOW!
But I think we're going to need literally quantum advances in energy storage technology
You mean the absolute smallest possible advances?
Food crops as energy sources was never a good idea, we didn't breed them for their modern harvestable energy content, and even if we did we'd be offsetting fuel crops.
Actually, food crops with a few exceptions (like spices) have always been energy sources. They're just energy sources for people and domesticated animals. I agree that algae oil is a better use than shifting food crops from high value human consumption to low value energy production.
Hydroponic Algae is several orders of Magnitude less complex than Hydroponic food crops.
Algae is a free floating aquatic plant so a lot of the labor intensities go away in the blink of an eye, and it has a higher plant density than hydroponic corn.
Hydroponic Wheat/Corn/etc is more expensive because it's wasteful and increases the energy costs associated.
Need to separate your Algae from the water? Sieve.. isn't so simply for corn, etc as they have to sit in racks and only their roots are being bathed and all kinds of other complexities.
All you need to grow hydroponic algae is water circulation, sunlight, carbon dioxide and some nutrients in the water [clean up fertilizer polluted water anyone?]
and the "wear and tear" on transparent plastic tubes that simply have algae-bearing water running through them isn't going to be nearly as bad as other hydroponics.
In short: bad comparison.
If you cannot keep politics out of your moderation remove yourself from the Mod Lottery.. NOW!
Algae is a free floating aquatic plant so a lot of the labor intensities go away
Hydroponics isn't expensive because of labor. The labor on a hydroponic farm is, if anything, lower than on a conventional farm. It's expensive because of the massive amount of plastic and steel that you need. You're talking endless *acres* of plastic. And all plastics suffer UV degradation to some degree.
Hydroponic Wheat/Corn/etc is more expensive because it's wasteful and increases the energy costs associated.
Hydroponic *everything* is expensive because of capital costs. Staples are simply not grown in hydroponics because nobody wants to pay a fortune for them. The only things that are generally economically justifiable to grow in hydroponics are things that are *already* expensive due to labor costs.
Sieve.. isn't so simply for corn,
I take it you've never heard of a combine.
Again, it's not the harvesting that's the issue. It's not marginal costs at all. It's capital costs.
All you need to grow hydroponic algae is water circulation, sunlight, carbon dioxide and some nutrients in the water
You've made it obvious that you've never done hydroponics in your life.
and the "wear and tear" on transparent plastic tubes that simply have algae-bearing water running through them isn't going to be nearly as bad as other hydroponics.
Again, you make it quite obvious. UV creates free radicals in the plastic which causes crosslinking, making the plastics brittle. It happens in all plastics. Untreated thin film polyethylene (the cheap stuff) generally lasts for under a year before it becomes semi-opaque and so brittle even the stresses of a light breeze can break it. About the longest you'll get is thick, rigid, UV-treated polycarbonate, which is probably good for about 10 years in this kind of role, but I doubt they'd even dream of paying for that. They'd probably go with UV-treated PVC thin film tubing, good for 2-3 years. Or they might use some sort of fluorinated thin film. But that's still monstrously large capital costs for this kind of coverage, for such tiny revenue per acre (~$10k/year).
You're not made of Tuesday!
Ahh, but their forgot the time aspect of this: that acre of land produces only so much grass per unit time, so technically the units should be miles per (acre * year) or some such.
In other words,
d/(d*d*t) or 1/(d*t)
So it really is an area swept through space-time rather than a line through space.
www.eFax.com are spammers
No, you were right first time. Pac-Man is a two dimensional game and you gave mm^2 which is a two dimensional result!
Nick
And their design was apparently conservative: you could build it, starting TODAY.
No one has demonstrated sustained useful greater than unity energy yields from fusion outside of bombs and stars. It is entirely possible that their design would work, but the track record of fusion attempts says its unlikely. Now don't get me wrong, I'm all in favor of fusion research, and I think it's worth spending money on. But, when the fundamental concept your engineering project relies upon has not been demonstrated in a manner that obviously scales to your project, calling it conservative is a stretch. In fact, calling it engineering is a stretch -- it's scientific research. Once they have a scale model and *strong* reason to believe it will scale properly, then you can call it a viable design -- but until it or something like it has been demonstrated at scale, you can't call it conservative.
Google doesn't agree:
1.0 mpg = 86 furlongs per firkin
Sometimes, Google gets it wrong, and it did so in this case. Both the gallon and the firkin are defined differently in US and imperial units. I explicitly said US gallons and US firkins, and supplied a link where the unit definitions could be found. A US firkin contains 7.875 US gallons (29.81 L). An imperial firkin contains 9 imperial gallons (40.91 L). Here are the conversions including mixed units:
1 mile per gallon (US) = 63 furlongs per firkin (US)
1 mile per gallon (US) = 86.46 furlongs per firkin (imp)
1 mile per gallon (imp) = 59.95 furlongs per firkin (US)
1 mile per gallon (imp) = 72 furlongs per firkin (imp)
So Google was apparently using US gallons and imperial firkins - a real screw-up and an astonishing inconsistency! It's worth checking up on Google's answers, rather than blindly accepting them.
To be absolutely pedantic, of course, we must note that these calculations use US liquid gallons, not the smaller US dry gallons, and that the US firkin is a quarter of a standard US barrel, not the very slightly smaller beer barrel or the rather larger oil barrel (neither of which would result in the 86 figure, anyway).
Those who can make you believe absurdities can make you commit atrocities. - Voltaire
1 mile per gallon (imp) = 59.95 furlongs per firkin (US)
should be:
1 mile per gallon (imp) = 52.46 furlongs per firkin (US)
if it actually matters to anyone, that is...
Those who can make you believe absurdities can make you commit atrocities. - Voltaire