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Re: biodiesel is a nonstarter
notarboca   4/23/2012 12:23:36 PM
It is good to see two opposing viewpoints being debated without degenerating into a flame war.  Try that on most other internet boards:-)  Keep up the good work, gentlemen.

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Re: biodiesel is a nonstarter
jeffbiss   4/23/2012 11:49:37 AM
No argument there. Although we're not impoverished, there's no need to subsidize delusion. But the corruption of special interest money in our politics is another discussion.

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Re: biodiesel is a nonstarter
warren@fourward.com   4/23/2012 11:45:27 AM
But biodiesel is subsidized by an impoverished nation (us) to the tune of at least $1.00 a gallon, and that is certainly unsustainable.  Plus it is causing famine in many areas of the world as we convert food to fuel. 

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biodiesel is a nonstarter
jeffbiss   4/23/2012 11:29:46 AM

Biodiesel not a finite commodity? It most certainly is:

Soybeans yield: (48 gal/acre/yr)(125 kBTU/gal) = 6000 kBTU/acre-yr

Soybean biodiesel equivalent acres: (3.8325 10E13 kBTU/year petroleum use)/(6000 kBTU/acre-yr) = 6.3875x10E9 acres planted with soybeans/year

(6.3875x10E9 acres soybeans/year)/(320.9x10E6 total acres planted in 2009) = 1990.5% acres required to produce biodiesel to replace oil as compared to current agricultural use.

For sake of comparison, the USDA reports that the US planted and harvested 75.208x10E6 acres of soybeans in 2011. According to "Green fuel for the airline industry" by David Strahan 13 August 2008 From New Scientist Print Edition the aviation industry uses 5x10E6 bbls/day. Therefore:

Soybean BTU yield: (75.208x10E6 acres)(6000 kBTU/acre-yr) = 4.51x10E11 kBTU/yr

Aviation use: (5 x10E6 bbls/day)(42 gal/bbl)(365 days/year)(125 kBTU/gal) = 9.58x10E12 kBTU/year

Soybean yield as percentage of current use: (4.51x10E11 kBTU/yr)/(9.58x10E12 kBTU/year) = 4.71 %

I don't see that as sustainable. The jet fuel test only serves to delude people into thinking that we can engineer our way out of this problem. The only way to sustainability is to reduce human population and become ever more efficient.

Rob Spiegel
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Re: Bluer Skies
Rob Spiegel   4/23/2012 10:36:59 AM
I agree, Warren, that cost in an important factor. But cost changes. As demand for energy increases -- and it will dramatically as the world emerges from this downturn -- and as oil becomes more and more difficult to extract, the relative cost of alternatives will change as compared with oil.

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Re: An invasive specie
RNDDUDE   4/23/2012 10:31:07 AM
Wow, God got brought into this really quickly. Firstly, the term biofuel covers a variety of products created from a variety of feedstocks. I would agree that corn-based ethanol is a bad idea on many levels, but the article was about biofuel compatable with jetfuel, which would be a biodiesel, not ethanol. I was actually surprised that they were using a biodiesel formulated from waste cooking oil, nothing wrong with that, but it is a rather difficult fuel to assign cost to....if you can get the waste oil for free, it can be relatively economical, as many home-based biodiesel brewers will attest. The more interesting biodiesels are being made from non-food based crops and show a good potential. Unlike cars, the aviation industry will always be using liquid fuels, the promise of using biofuel is that it ultimately removes the feedstocks from petroleum and shifts it to organic-based, which means it in no longer a finite commodity.

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Re: Bluer Skies
Stuart21   4/23/2012 10:27:09 AM

Warren said "Global warming is another unsubstantiated and foolish claim that ignores reality- solar flares."


"Plus, one volcanic eruption has more effect on our climate than any thing we can do."

Absolutely untrue. If that were the case, the CO2 record from Mauna Loa would show not spikes, but huge jumps whenever a Pinatubo or and Iceland volcano blew off. However, there is NO visible change from the steady climb which fits the record of fossil fuel use by man. Google & view it for yourself.

The planet emits ~ 200 million tons of CO2 p.a. Man emits 8,500 million tons. 42.5 times as much. (NOAA figures - other estimates are 100 to 200 times as much!)

The steady state CO2 level for mans current emissions is 1.2%.

"But this is a big old world, and we are a very, very small part of it."

If you use the word universe instead of world, yes I could agree with you. But man is well on the way to destroying the earth (for human habitation) and vested interests such as Heartless Inst. et al are doing everything they can to stop any efforts to prevent catastrophe. Yes, a - real - conspiracy.

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An invasive specie
jeffbiss   4/22/2012 7:26:33 PM

First, Miscanthus X Gigantheus is a hybrid of a Japanese grass, and so is an invasive specie in North America and so does affect native species. Second, there is the problem of production to meet our current energy needs:

Gasoline energy content: 125 kBTU/gal
Ethanol (E85) energy content: 80 kBTU/gal

Grass ethanol yield: 3,250 gal eth/acre-year

Oil consumption/yr: (20 x10E6 bbls/day)(42 gal/bbl)(365 days/year)(125 kBTU/gal) = 3.8325x10E13 kBTU/year

Ethanol equivalent acres: (3.8325 10E13 kBTU/year)/[(80 kBTU/gal)(3250 gal eth/acre-year)] = 147.4x10E6 acres planted with grass/year

(147.4x10E6 acres grass/year)/(320.9x10E6 total acres planted in 2009) = 45.9% additional acres under cultivation to produce ethanol to replace oil.

While we will not be totally replacing oil with ethanol, this serves to show what scale would be required. Corn is even worse as its ethanol yield/acre is less. Also, you must account for the resources, for example fuel and water, required to plant, grow, harvest, convert, transport, etc. the crop for ethanol production. The same goes for biodiesel but with a different crop and yield (see http://en.wikipedia.org/wiki/Table_of_biofuel_crop_yields).

As biodiesel has about the same amount of energy as diesel, the number of acres required for any given crop that can be grown in the US is staggering, for example soybeans yield 48 gal/acre-year (6000 kBTU/acre-yr) and while peanuts produce more, 113 gal/acre, they can't be grown all over the US. This bodes ill for wildlife, such as orangutans as palm oil yields 635 gal/acre and so with the push for carbon-neutral "green" fuels, Indonesia will be destroying orangutan habitat, and thus killing orangutans, to create palm oil plantations to meet the demand of clueless "greenies".

So, while grass has a higher energy yield than soybeans, 260x10E3 kBTU/acre/yr compared to 6000 kBTU/acre/yr, nothing we do is sustainable at the current human population and resource use.

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It's about population
jeffbiss   4/21/2012 7:16:06 PM

I don't believe in god, so that lord thing doesn't fly. The fact is that there are far too many people using finite resources, period. For example, the US has about 5% of the world's human population and uses about 25% of the earth's resources. That means for everyone to enjoy our standard of living the earth can sustain only 1.2 billion (300 million x 4). Therefore the only reason that 7 billion can exist is that so many do with so little. We are past peak oil and peak coal, which means that the era of cheap food is over. Also, China cannot feed itself and is leasing land in other nations to grow its crops, which means that those nations have less capacity for their own populations, which are forced to encroach into wildlife habitat.

So, the only political issue at hand is deluding ourselves into thinking that population isn't a problem.

As for global warming, it's obvious that it's not about global warming but the economic implications. You, being a free market ideologue, simply don't like the fact that the free market is wholly incapable of solving problems and so political will is required, such as mandating greenhouse gas emission limits and efficiencies for everything we do and use. It is a fact that the denier community has nothing to back up their denial except economic arguments, which are invalid in this discussion, and ideological arguments, such as we are too insignificant, god designed the earth for us and so it cannot fail, technology will provide a solution, and the free market will solve any problem, all of which are simply false.

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bobjengr   4/21/2012 3:48:43 PM
The company I own has a client in South Georgia (USA) involved with planting 30,000 acres of a grass called Miscanthus X Gigantheus.  The specific purpose being (after processing ) for the creation of biomass and eventually biofuel.  I will admit, I was very skeptical at first but I have seen the data relative to yield and there is a viable market for the product.  We will also be taking carbon credits for his investment.   One other thing, it does not take away from edible foodstuffs AND can replinish neutrants lost from seasonal planting.  Planting the rhizomes is the main difficulty because suitable equipment to automate the process is quite expensive--coming down in cost each year but still very expensive.  I find this to be fascinating technology, even for a mechanical engineer.   If you go online, look up Mississippi State University, ecology. There is a weath of information realtive to that particular crop and others.  Thanks

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