Here's an odd fuel alternative.

[jchnhtfd]

There is a consideration with alcohol fuels (and biodiesel, except when using waste cooking oil and the like) which I haven't seen here, so I'll just wave my little oar...

It takes energy -- from somewhere -- to grow the raw material (e.g. corn) -- and to ferment it, and to distil it. The last time I took a good look at the numbers, sad to say, it took more energy, in fact, to produce the stuff than the stuff contained. Ethanol is used in motor fuels not because it saves on crude oil use -- it doesn't, it increases it -- but because when burned in the average automotive engine it tends to reduce the amount of hydrocarbons and carbon Monoxide in the exhaust, thus reducing some forms of air pollution (e.g. that famous LA smog).

[Overmod]

We had a recent thread about biodiesel IIRC... probably more than one.

To expand a bit on Dave's comments above: vegetable oil technically 'burns just fine' in many kinds of compression-ignition engine; what normally happens is that the chemical composition of "commercially-cost-effective" oil (usually a code-word or euphemism for spent frying oil from restaurants) is modified, e.g by treating it with a base like lye, to make it behave more predictably when run through precise injectors in small quantities, and to form a proper spray and oxidize with appropriate speed and completeness when injected. Naturally, the amount of modification you do has an impact on the cost... and hence the potential profit... from the refining.

Now, remember that most railroads are NOT going to jump on the 'used french-fry oil' bandwagon... they are much, much, MUCH more concerned with assuring that engines don't conk out on the road than with updating the old UP 'heavy fuel" systems to heat the fry oil to the required temperature for it to inject properly! (This assumes that there is adequate used food oil within an appropriate transportation radius to satisfy demand in the first place...)

Note that the big thing of importance (at least in my not-so-humble opinion) is different from pure economics... or filtering quality. Diesel fuel is also a lubricant for parts of the injection system. Lots of us diesel nuts already run lubricosity additives like Stanadyne or TD-4. The reason this stuff isn't incorporated in ordinary diesel fuel is... well, it costs a fair amount, and to my knowledge isn't effectively synthesizable from 'renewable resources.' If you look at the fine print in light-truck owner's-manual diesel sections, you'll often find disclaimers that point out you shouldn't use more than some relatively low percentage of "biodiesel" -- somewhere around 15 percent being the figure I remember without going downstairs to pull out the Duramax and PowerStroke stuff.

While I can -- and do -- agitate to get properly-chemically-engineered forms of biodiesel produced and marketed, I suspect we are a fairly long way away from guaranteed standards of cost-effective composition and lubricosity, even in fuels derived directly from 'virgin' stocks. There are also problems with supply-demand analysis when the cost and risk of incremental facility construction and startup are considered -- higher demand often will NOT result in lower marginal cost, at least in the near term, so it would be imprudent (at best!) to assume that the marginal cost will come down below the opportunity threshold for fossil fuel following an increased demand by railroads.

Also, remember that the full cost of generation, transportation, storage, etc. is attributable to biodiesel production. A big piece of the economic picture for biodiesel in on-road use involves waiver of the tax involved on diesel fuel -- that's not a meaningful issue for locomotive diesel.

Remember that even with oil at $70 a barrel, there's no particular *shortage* of oil, and absent meaningful levels of terrorism or refinery disasters, no particular prospective shortage of refined/synthesized diesel fuels. (And, of course, there's a full supply and delivery infrastructure already in place and largely costed-down to deliver it!) If you run the numbers on biodiesel production cost, and then backtranslate from the equivalent cost per gallon of delivered biodiesel to get the effective alternative consumption curves for oil and refined products in other economies... well, something you do NOT get (peak-oil propaganda or not ;-}) is a shortage of fossil-derived diesel that's cheaper than reliably-sourced biodiesel in the required grade and quality for locomotive service.


BTW, it may be instructive to note what happens when acetone is run through typical high-speed-diesel injection and combustion cycles, often resulting in incomplete oxidation. That, I think, is a big reason it won't show up as a cosolvent in diesel fuels. (Technically, I don't believe acetone forms an "emulsion" with fuel oils, as one of its neat characteristics as a solvent is that it's miscible with a fairly wide range of both polar and nonpolar materials -- as Dave points out, a solution of vegetable oil in acetone IS long-term stable, whereas some form of surfactant or 'soap' would be required to stabilize an emulsion). A more important issue is: Where will the acetone come from? It's a byproduct of conventional phenol synthesis... and you can convert isopropanol (aka isopropyl alcohol)... but I don't see any way to start with cheap ingredients and make acetone-solvent fuel that is more cost-efficient, per delivered gallon, than alternatives. Please correct me if this is wrong.

[Sterling1]

All I see here is ethanol and methanol, what about biodiesel?
I just saw a NREL report where they used a GP38-2 powered by biodiesel.

Growing biofuels takes up fallow land, often paid off with government subsidies to keep prices at a certain profitable level for farmers.

Matt

[Anonymous]

mehrlich,

To add to Overmod's comments, higher chain alcohols such as isopropanol and butanol do have higher energy densities than methanol and ethanol, and come close to matching the energy density of gasoline and diesel. It is possible to distill higher chain alcohols from both starches and cellulose, but again the money you spend on all the equipment and ingredients will far outweight the money you would otherwise spend on gasoline, even with the projected price increases coming down the road. Unless you are making alternative fuels from the left-overs of some other process you are involved in, or unless you are making the stuff just for the fun of it, we should leave the production of alternative fuels to the mass producers.

FYI - I did find a reference to experiments back in the 1980's in which folks were adding solvents to used vegetable oils and then burning the mixture in regular diesel engines. The article mentioned the use of alcohols as the solvents. I wonder if anyone had tried to mix acetone with vegetable oil to come up with an emulsion that could burn in compression-ignition engines. Since acetone immediately miscates fully with other liquids (and stays fully mixed over time), it is possible the solvent action of acetone would act to counter the carbonization and plugging characteristics of raw vegetable oil on the injectors of compression-ignition engines (and vis versa e.g. the solvent action of acetone would be mitigated by being blended with a naturally lubricating liquid). Since used vegetable oil is a byproduct of other processes, it is appropriate to try and make this otherwise low value waste product into a valuable fuel alternative, as long as the cost to do so is less than the increased cost of petroleum-based fuels.

[ericsp]

California gasoline contains ethanol. Gasoline stations smell like wineos now, except for the body odor. There are now companies building plants in California to make relatively large amounts of ethanol.

[selector]

Point taken, m. [:)]

I would caution use of the mixture for those whose warranties are still current. My Tundra is limited to 5% ethanol by volume.

It would be interesting to do some work-up math and see how long it would take you to recoup any costs for the still, and then factor in operating costs. Variations in the cost of fuel will render the answer tentative, but still worth a serious look.
Regards.

[Anonymous]

Thanks overmod, I guess you pretty much answered my question!

m

[Overmod]

merlich, I think you need to Google up "E85" and "FFV".

85% ethanol as a motor fuel, and fully-engineered vehicles that can run on it (or, with minimal difficulty, on gasoline when E85 is not available for any reason), have been around for quite a few years now. Ford built a whole bunch of Tauruses (Tauri?) with flexible-fuel equipment, and I still see one from time to time.

In general, energy density of ethanol (or methanol) is not as good as gasoline or diesel, and the higher heat of vaporization makes starting and operation in colder weather more difficult. One reason alcohol is used as a racing fuel is that it absorbs heat from the intake tract and engine -- helping to keep critical parts cool more effectively than the circulating engine coolant can -- and will not 'detonate' as readily at higher manifold pressure (i.e. has a higher "octane rating" equivalent).

I can't recall, offhand, any method *other* than stills for making ethanol effectively. Industrial facilities just use larger fermenters and more effective methods of distilling off the volatile alcohol. Isn't it fortunate that Mother Nature has provided effective strains of organism that produce alcohol from complex polysaccharides, and that are tolerant to relatively high levels (to 18% that I know of) of alcohol in solution. That's the sort of self-replicating, cheap-to-run chemical kinetics that the nanotech guys currently dream about! (But even so, you'll find that the overall cost per gallon may be just as 'unfavorable' as the cost of much of the home-brewed beer is, on a bottle-by-bottle net basis!)

[csxengineer98]

alcohal is nasty on rubber gaskets and seals... it will desolve them over time..so unless you replace eveything that is rubber that will come in contact with it... your going to have bigger problems down the road.... and that alone can be a major expece if your trying to make a fleet of anything run on alcohal....
csx engineer

[Anonymous]

Selector,

Look, all I want to do is save a few bucks by distilling a little alcohol myself to mix with the gasoline to make it go a little farther. No more, no less.


m

[selector]

Not wanting to sound like a wet rag, the meta-question is, "Why are we looking for alternatives in fuel?" The answer is that we keep building kids at a rate that yields a net increase in energy demands from year-to-year. No form of energy will solve this crash-waiting-to-happen for humanity. We need to accept that, if we beat the crash, we will eventually leave this planet to begin the history of planetary exploitation all over again.

[martin.knoepfel]

The famous steam-engine-designer Porta worked in Cuba on a similar project. They wanted to build a tank-engine that was fired with byproducts from the sugar-cane-refineries. I never heard this materialized.

[daveklepper]

Not very efficient. Also there are more efficient ways of making agricultural products into fuel. Soye beans for one. But all that takes food-producing agricultural land and directs it for transportation fuel. Since a Cadillac owner can probably outbid a third world mother with children, too much biofuel may lead to global hunger.

[Anonymous]

I was at a pre-Easter party last weekend, and one of the guys told us a hilarious story about visiting a still. Yes, there are people who use stills to make alcohol. To make the long story short, evidently it's legal if you distill your own alcohol (in this case ethanol) as long as you don't sell it, or it's as a fuel.
So...why couldn't anyone who wanted to do it manufacture their own alcohol as a motor fuel? This guy bought some kind of kit to get his started, and he uses bran, which he buys at the feed store. I forget how many gallons he can make an hour, but it was pretty significant. You can already buy a gasoline/ethanol blend up in the midwest. Maybe someone could develop an engine that could burn half/half or even 100 % ethanol. I know some dragsters, sprint cars and Indy cars do. Just food for thought and discussion.


mike