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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."
Miles per acre? What's that in rods per hogsheads?
...now all we need is a fuel that comes in the form of a long string, and we can finally express fuel efficiency as a dimensionless number.
BTW, 20 miles per gallon works out to 3.4409911e+10 inverse acres. Or, to look at it another way, one gallon per 20 miles is 2.9061395e-11 acres, or about 0.12 square millimeters. That's the diameter of the imaginary thread of gasoline that your vehicle is gobbling, Pac-Man-like, as you drive down the highway.
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.
The real blow-it-out-of-the-water numbers are when you eliminate "bio" from the equation, period. Corn yields 300-450 gallons of ethanol per acre. Sugarcane, about 550-850 gallons or so. Switchgrass can theoretically yield over 1000 gallons per acre and algae 5000, although those numbers are likely to get way smacked down by reality (especially the algae numbers). But let's just go with them. CAFE average is ~24mpg, and you get less mpg on ethanol, but hey, let's just say our cars get 40mpg. The average driver goes 12k miles per year, so corn can support 1.3 drivers/acre, sugarcane 2.3 drivers/acre, switchgrass 3.3 drivers/acre, and algae a way-over-optimistic 16.7 drivers/acre.
A compact linear fresnel reflector solar thermal generating station produces about 1MW nominal capacity for every 4 acres and has about a 20% capacity factor (in non-optimal sites). That's an actual MW per 20 acres, or 488,288,000Wh/acre-year. The Volt and Tesla Roadster both use about 200Wh/mi, so let's go with a more pessimistic 300Wh/mi after losses and with less efficient designs. That's 121.7 drivers per acre. I.e., it beats the pants off even the highly speculative numbers for algae. And it uses no water or fertilizer -- and we use *way* too much water as it is.
If you want land efficiency, converting the sun directly to electricity and using that electricity directly rather than having the intermediary stage of "plants" is the way to go. And we farm too darn much of this planet as it is already.
You're not made of Tuesday!