Brazil's ethanol yields nearly eight times as much energy as corn-based options, according to scientific data. Yet heavy import duties on the Brazilian product have limited its entry into the United States and Europe.

The above comment is journalistically sloppy.  Ethanol is ethanol.  Sugar cane likely yields 8 times the amount of ethanol as what you would get from a comparable biomass of corn.  (more sugar=more ethanol) and I'll even believe at an 8-1 ratio.

So, in a tropical clime, in a rich alluvial basin, it's possible at present to grow lots more sugar faster than in a temperate clime on worn out soil.  Because of climate and longstanding overuse of arable land in our role as the global foodbasket, the U.S. likely does not have a rich sugar production option even remotely approaching Brazil's.   

Barring some phenomenal breakthrough in enzyme chemistry, which enables an exponentially greater sugar recovery from bulk cellulose (like switchgrass or hemp) I don't believe it's possible for the U.S. to emulate Brazil - at our current rate of energy consumption - using sugar as the raw energy source.

This is a USDA report on ethanol EROEI  (1995)
http://www.ers.usda.gov/publications/aer721/aer721.pdf

Here is a web site for the Minnesota dept. of agriculture. The info posted on this web site is not only misleading or even BS, it comes close to being an out right lie. There is little possibility, they do not understand the deception of their post. 
http://www.mda.state.mn.us/Ethanol/balance.html

Fuel * Energy yield Net Energy(loss)or gain
Gasoline 0.805 (19.5 percent)
Diesel 0.843 (15.7 percent)
Ethanol 1.34 34 percent
Biodiesel 3.20 220 percent

Ethanol and biodiesel are not presented in the same context as Gas & diesel. Using the deceptive Minnesota numbers produces the following rather depressing results.

To produce 805 btu's of gas requires 1000 btu's of energy in, so you use 195 Btu's to produce 805 btu's of gas for an ERoEI of 4.13 or a net loss of 19.5 % of 1000 btu's. =413% gain

To produce 843 btu's of diesel requires 1000 btu's of energy in, so you use 157 Btu's to produce 843 btu's of diesel for an ERoEI of 5.37 or a net loss of 15.7% of 1000 btu's. =537% gain

To produce 1340 btu's of ethanol requires 1000 btu's of energy in, so you use 1000 Btu's to produce 1340 btu's of ethanol for an ERoEI of 1.34 or a net loss of 74% of 1340 btu's. = 34% gain

To produce 3200 btu's of biodiesel requires 1000 btu's of energy in, so you use 1000 Btu's to produce 3200 btu's of biodiesel for an ERoEI of 3.20 or a net loss of 31% of 3200 btu's. =220% gain

To produce 843 btu's of diesel requires 1000 btu's of energy in, so you use 157 Btu's to produce 843 btu's of diesel for an ERoEI of 5.37 or a net loss of 15.7% of 1000 btu's. =537% gain

In this case, the calculation is done usint the difference between the btus of energy input (1000) and diesel output (843), to "use" 157 bts.

To produce 1340 btu's of ethanol requires 1000 btu's of energy in, so you use 1000 Btu's to produce 1340 btu's of ethanol for an ERoEI of 1.34 or a net loss of 74% of 1340 btu's. = 34% gain

In this case the calculation "uses" the full number of btus input.

Why?

Good kwestin magne....,

Because in the production of diesel, you only wind up using a fraction of the petroleum you've recovered from the ground to power the entire recovery and distillation process.  This makes diesel or any petroleum fuel extract for that matter a net energy source. 

Whereas with ethanol, though it's still an energy source, it's much less of a source than petroluem.  I'd put it between petroleum which is a pure concentrated energy source, and hydrogen which is not an energy source at all, but rather, an energy transport.  With ethanol, though you gain 340 BTU, you must expend 1000 btu's of petroleum energy to produce 1340 btu's of ethanol energy.  If it was a pure transport, you'd have something ridiculous like 600 btus of ethanol energy *produced* by consumption of 1000 btu's of petroleum energy.  

I haven't looked into current hydrogen generation schemes, but I suspect you'd find some large coal fired electrical power generation going into an electrolysis of water to liberate hydrogen.  So you'd convert X BTU's of coal power to generate X-Z BTUs of hydrogen - cause cars won't be coal powered - but they might conceivably be hydrogen powered if the infrastructure to build hydrogen stations is ever deployed.

With ethanol, though you gain 340 BTU, you must expend 1000 btu's of petroleum energy to produce 1340 btu's of ethanol energy.

Why not expend 1000 btus of ethanol energy to get your 1340 btus?

Never mind. I can't play like this very long. Sorry, but this in particular is pure snow-job.

This isn't a question of logical equivalency,

Flat wrong on all points.

If you'd said that about hydrogen, you would've been correct.  However, for a simple volatile liquid handled and stored at room temperature, the infrastructure to distribute ethanol already exists en masse.  Gas stations work just fine with ethanol.  The process is already fully in use on an industrial scale in Illinois where I've been working the past several months - no modifications required.

If you don't get the physical inequality between stored energy locked in holes in the ground (oil) and cultivated source material (sugar) requiring the use of stored energy (oil) to manufacture at a tiny fraction of the capture and use efficiency, then it's time to give up on trying to get you to understand the difference between energy sources and energy transports.

But it's just oil - there are other fossil fuels, other energy sources, right?

To evaluate other energy sources it helps to understand the concepts of Net Energy, or the Energy Returned on Energy Invested ratio (ERoEI). One of the reasons our economies have grown so abundant so quickly over the last few generations is precisely because oil has had an unprecedently high ERoEI ratio. In the early days of oil, for every barrel of oil used for exploration and drilling, up to 100 barrels of oil were found. More recently, as oil recovery becomes more difficult, the ratio has become significantly lower. Certain alternative energy 'sources' may actually have ERoEI ratios of less than one, such most methods of industrially producing biodiesel and ethanol. That is, when all factors are considered, you probably need to invest more energy into the process than you get back.

Hydrogen, touted by many as a seamless solution, is actually an energy carrier, but not an energy source. Hydrogen must be produced using an energy source such as natural gas or nuclear power. Because of energy losses in transformation, the hydrogen will always contain less energy than was invested in it.

However, for a simple volatile liquid handled and stored at room temperature, the infrastructure to distribute ethanol already exists en masse.

If you don't get the physical inequality between stored energy locked in holes in the ground (oil) and cultivated source material (sugar) requiring the use of stored energy (oil) to manufacture at a tiny fraction of the capture and use efficiency,

If you don't get that you have to count all the energy inputs

EROEI does take into consideration all the inputs. 

Ball's in your court P6, please disclose the alternative energy analysis on which you've hung your hopes.  I'm looking forward to having my careful study of this topic over the past several years debunked.  I'd consider it a damn sight worse to be wrongly Malthusian than to simply have my analytical errors pointed out.  . 

To evaluate other energy sources it helps to understand the concepts of Net Energy, or the Energy Returned on Energy Invested ratio (ERoEI). One of the reasons our economies have grown so abundant so quickly over the last few generations is precisely because oil has had an unprecedently high ERoEI ratio....  Certain alternative energy 'sources' may actually have ERoEI ratios of less than one, such most methods of industrially producing biodiesel and ethanol. That is, when all factors are considered, you probably need to invest more energy into the process than you get back.

Hydrogen, touted by many as a seamless solution, is actually an energy carrier, but not an energy source. Hydrogen must be produced using an energy source such as natural gas or nuclear power. Because of energy losses in transformation, the hydrogen will always contain less energy than was invested in it.

Gentlemen:

I am saying one thing:

To produce 843 btu's of diesel requires 1000 btu's of energy in, so you use 157 Btu's to produce 843 btu's of diesel for an ERoEI of 5.37 or a net loss of 15.7% of 1000 btu's. =537% gain

To produce 1340 btu's of ethanol requires 1000 btu's of energy in, so you use 1000 Btu's to produce 1340 btu's of ethanol for an ERoEI of 1.34 or a net loss of 74% of 1340 btu's. = 34% gain

If you run your calculation differently, your comparison is void.

There's a lot I'm not saying. For instance, I'm not saying a transition from gasoline to ethanol will be simple or easy or that changes in our patterns of activity will not be necessary.

To make matters worse--much worse--if Cnulan were "wrong" and some net energy could be extracted from this process, this would be an unmitigated disaster for the 3rd world as land imperialism became a total preoccupation of the great powers.

Work in progress, because contrary to the ideologues bizarre reality avoidance schemes, polity=way of life.  The implicate order in human affairs (TEP governing subset) has already taken the decision to maintain its current standard of living.  In order to accomplish this, a series of things must happen, and some of the most critical of these have been works in progress for some time now.

1. Privatization of natural resources including water.  (this is the precursor to land imperialism)

2. Die-off - between 4 and 5 billion humans gotta go, gotta go, gotta go....,

3. Permanent Dickensian wealth distribution.  (corporate feudalism)

Of course, implementation of this reality shift is a multi-generational process, in this case, the process began in earnest shortly after the publication of The Limits of Growth by the Club of Rome.

If you run your calculation differently, your comparison is void.

No..., if you run the calculation differently, you wind up with a set of inexplicable assumptions that cannot be realistically associated with resource, infrastructure, social, or political history or reality. This is the most compelling reason to make practical efforts to architect local, high-value, autonomous black partisan models of sustainable resources and relations.  Anything less is simple acquiescence to the momentum and inertia of the Dickensian mainstream..., oh, and most of those folks in the mainstream don't see it coming either.

Cnulan: Work in progress, because contrary to the ideologues bizarre reality avoidance schemes, polity=way of life.  The implicate order in human affairs (TEP governing subset) has already taken the decision to maintain its current standard of living.  In order to accomplish this, a series of things must happen, and some of the most critical of these have been works in progress for some time now.

Word.  In fact, that's the entire raison d'etre of my weblog.  In the 3 years I've been feeding it I've experienced some radicalization as I become aware of things like this.

BTW, that link to eroei.com is really great.  I want to push that hard.

So I'm reading Hobson's Choice and encounter the notion of eugenic imperialism. This seems to me to describe the modus operandi of the U.S. very nicely.  Of the various forms of imperialism which you summarize, which form do you consider most onto our way of life?  How do you see our societal norms holding up under the strains of declining net energy over the next few decades?