Info to ompare non-gasoline fuels, please?

Diesel fuel comes in several varieties, and it is “kerosene”, or something like that. I do recall enough chemistry to know that pretty much all petroleum products, even after refining, are mixtures of varous (related - excluding deliberate additives) carbon compounds.

Jet fuel is also a form of “kerosene”.

And I heard a feature article on NPR in the last several days that told how a band had bought a conversion kit for their diesel-powered van(? bus?) that enabled it to burn cooking oil (except on startup).

The petroleum supply crisis seems to be closer than we knew. I am asking whether we will have fuel options that permit us to continue to run cars and planes as we have and presently do (assuming that all the air carriers don’t go belly-up).

:smack: :smack:

I meant to say compare

What exactly do you want to compare? Chemical formulas? Energy content? Relative mpg? You might need to be more specific. In the mean time, check out this little comparison chart generator (“all fuels” and “all properties” would be a good place to start – that gives this chart). That should give a lot, if not all, of the information you want to know.

Sorry, I’m not usually so vague. And I didn’t think I was commiting that sin at the time. :o

I spent a number of hours overnight googling and reading up on diesel, jet fuel, and biofuels … and writing a letter to one of my senators. Not caught up on my sleep yet, but maybe this will convey my question more clearly. What I think I’m trying to ask is, to what extent is it possible to replace petroleum-derived fuels with biofuels. That’s why I mentioned the guys with the diesel-powered van or whatever who are burning used deepfryer oil - except for startup. Actually, that may be what set all this off. I’d heard of this engine mod before, but I think the thread about “how soon will the petroleum deposits renew themselves” made me focus on the problem.

However, what confuses me is that there are noticeable chemical differences between oil and the vast array of -ane hydrocarbons that constitute fuel. Just because the oil has been repeatedly maintained at several hundred degrees doesn’t change it that much. If it did, we’d be poisoned by our french fries. :eek: Don’t the -anes oxidize more completely than oils?

Second try:
Realistically, is it possible/likely that biofuels can be a) developed (cost-effective methods of transforming bio-oils into something more readily burnable in an engine?) and b) manufactured in sufficient quantities to replace the diminishing - eventually ending, as there are so many other, less flexible and presumably more crucial, uses for petroleum (e.g., plastics). Can we switch over totally to renewable sources, while we’re waiting for hydrogen (or something else that’s also better)?

I think maybe the answer has several parts. Sorry if this is too smart ass, but it’s kind of important to be clear about this.

Is it possible to make bio-derived products to replace all fossil-fuel derived products?

Is it economically feasible to do so right now?
Well, part of that answer depends on how you assign costs like environmental damage, conflict over oil reserves, etc. And that’s too big a question to answer quickly here.
If you don’t consider those costs important, then the answer is “No, because otherwise companies would use bio-derived products to save money.” (And when that’s what they do, we don’t consider it a fossil-fuel product at all, like cooking oil or rubbing alcohol).

Will it ever become economically feasible?
If you think that fossil fuel costs will grow higher without limit, then of course it will be cheaper at some point to use bio-fuels. Of course that cost may be high enough that we’ll stop using a lot of previously fossil-derived products.
And, as an aside, hydrogen is NOT a source of power. Hydrogen is just a way to store energy, like a battery. You use up electricity to make hydrogen, then carry the hydrogen somewhere and burn it to get (a little bit less) electricity back. You still need to get the electricity from fossil fuels, burning wood, windpower, a bunch of guys on exercise bikes or what have you.

Not at all! I love precision.

Can you give a precis? I’m trying to arm myself with a better understanding of this issue before starting a GD thread. If I must choose between making an idiot out of myself in GQ or GD, I’ll take GQ, thanks. :slight_smile:

I was a biology AND anthropology major. Does that help answer the question? :slight_smile:
And I do understand something about accounting, including cost accounting.

That’s what I’m pondering.

My bad. :o :o

I know better, but I’d been too many hours without sleep when I wrote that first post. <sigh>

And thanks!

This doesn’t really answer your question on biodiesel, but you might want to peruse this thread on ethanol (and Cecil’s column on same) which is currently on the first page of CCC (ignore the stupid arguments). Not biodiesel related, per se, but there is a good discussion of the economic factors that affect the production of ethanol, and you might be able to use the information there to get a handle on broader alternative fuel issues. Also, linked to in that thread, is an Australian study on alternative fuels which includes a large section on biodiesel production. Might be worth a look.

Thanks muchly! I will read carefully. I knew that ethanol from corn is a taxpayer subsidy for ADM, :frowning: and there are probably no economies of scale to be obtained, given that we (and Canada) already grow zillions of tons of corn. But biodiesel is made from soybeans - or at least that’s what it says in the stuff I’ve read. And I have yet to see anything about whether it could become economic to produce. YNCT, of course, :dubious: so that’s why I asked.

Gee, I just noticed you’re from my old hometown. Work in the auto industry, perchance? :slight_smile:

Regarding the band that converted a bus to use ‘waste cooking oil’, I think they really mean it burns biodiesel. I’ve seen a hippie bus with ‘this van burns veggie oil’ painted on the back, and I think it’s the same idea – the vehicle burns used cooking oil, so it isn’t hurting the environment. Biodiesel isn’t really pure used cooking oil. It is the methyl esters of fatty acids, made by reacting used oils with methanol (in acid or with a catalyst). Presumably methyl esters oxidize better than unmodified fatty acids.

I know of one other type of vehicle that burns biodiesel – advertising trucks that drive around the city serving no purpose other than carrying a large billboard. Apparently there was enough of an outcry over the environmental damage of vehicles with no purpose but to advertise that they converted them to biodiesel, and now, of course, they do no environmental damage whatsoever, and you’re a hippie Communist if you think otherwise.

OK quickly then:

There are a lot of costs to burning fossil fuels that neither the seller or the user pays for, instead these costs are paid for by a bunch of other people. In economics, these kinds of costs are called ‘external costs’.

Some major fuel external costs:

Smog and particle pollution: burning both fossil and biofuel produce smog and particle pollution (‘soot’). Also gasoline vapors from gas stations and refineries contribute to smog. This affects the health and well being of the surrounding area, with smog travelling hundreds of miles. An electric battery/hydrogen car charged from wind/solar/dams doesn’t have this issue; if the car is charged from a fossil/bio power plant it does contribute to smog, though to a lesser extent than an internal combustion car.

Oil spills: Transporting oil (though not natural gas) can have damaging, though not generally permanent, effects on coastal areas.

Climate change: Burning fossil fuel, in internal combustion or electric plant contributes to global warming. Burning bio fuels releases only as much carbon dioxide as was absorbed to grow it, so it has no effect on climate change. Wind etc generation has no effect. This affects the entire world (pretty big potential external cost, then).

Landscape degredation: Hydro power dams necessitate flooding often large areas (see China’s three gorges or HydroQuebec’s projects), usually without the consent of the inhabitants. Wind power installations can affect the views of neighbors, who are not compensated. Large scale bio fuels could require more farmland, resulting in a loss of wildlife habitat (I’m not familiar with any studies of this issue). Coal mining significantly affects landscapes; oil and gas less so, though road building for exploration and extraction can fragment large wilderness areas.

International Relations: Currently regions and countries with large oil reserves carry extra significance in international relations. Some go so far as to argue that much of current U.S. foreign policy and military expenditures is based on securing access to oil supplies.
Now, from a ‘what should the country do?’ point of view, we should really account for these external costs, since we’re all paying for the sick people, hospital visits, etc., even though the person using the fossil fuel doesn’t.

So the question of whether biofuels are ‘economical’ from a country-wide perspective depends on how big you think all these various external costs really are.

I can’t be sure you’re right about this, without your reviewing the source information (I am not impugning your knowledge; just not certain you’ve got all the facts of this particular case). You probably know more about the science and/or technology than they do, :slight_smile: but I was just reporting what they said. Here’s the link, and there are several links for more information on biodiesel on that page. Most importantly, here’s the link to the Greasecar site. I haven’t yet read everything on the site, but on the home page they say, quite clearly, that their kit allows a diesel engine to run “straight vegetable oil,” and have repetitive warnings about contamination, which, IIRC, is not necessarily what you’re saying.

I admit I was incredulous about the whole business, but hearing the grease van story in the context of this summer’s gas (and diesel) prices was what started me on this track. Although I guess that the match to the fuel :stuck_out_tongue: was really the thread about how soon the oil fields would replenish themselves. :rolleyes:

I’d be very interested in your thinking - or that of anyone else who can give an educated opinion on how their conversion kit works.

TMI: Sorry I was so long getting back. I’ve had a rough couple of days, and I was determined not to post another response that wasn’t clearly phrased. :o My worst embarassments are intellectual ones.

I believe, although I’m not certain, that your veggie oil system differs from biodiesel in practice because the Greasecar requires an auxiliary diesel tank for startup, and only switches over to vegetable oil once everything is warm. That’s a little different story than biodiesel, which doesn’t require the additional fueling system. Since you’re talking about economics, you must realize that this incurs an additional cost: extra fuel tank, warming lines, and some switchover system. Also, if you’re concerned about emissions, there’s a fairly substantial amount of emissions produced on start-up, so you don’t get all the advantages of vegetable oil there.

Ayup. In a small engine/ powetrain/ alternative fuels/ aftertreatment strategy research and development group actually (although my personal knowledge of the broad range of alternative fuels issues is not great, some of the people I work with do have a broad range of knowledge).

You can use biodiesel or straight vegetable oil, although the juryseems to be out on whether straight oil will eventually damage your car.

These guys have a lot of information on making biodiesel and using straight vegetable oil or veg-oil diesel blends.

Wow, talk about information overload! :cool:

Thanks, guys. I think I’ve got enough references/resources. And I certainly do know lots more than I did several days ago, although I don’t think that my feelings on the subject have changed. This is a touchy topic with many people, not least because we’ve had a long (almost) free ride with Ma Nature’s generous dollops of energy resources.

I could use more commentary, if anyone is so moved. Otherwise I’ll let it all start percolating through the back of my head.